WEBVTT Kind: captions Language: en 00:00:00.000 --> 00:00:04.350 align:start position:0% foreign 00:00:04.350 --> 00:00:04.360 align:start position:0% 00:00:04.360 --> 00:00:16.150 align:start position:0% [Music] 00:00:16.150 --> 00:00:16.160 align:start position:0% 00:00:16.160 --> 00:00:19.269 align:start position:0% secure<00:00:17.160> contract<00:00:17.520> using<00:00:18.180> fuzzing 00:00:19.269 --> 00:00:19.279 align:start position:0% secure contract using fuzzing 00:00:19.279 --> 00:00:21.830 align:start position:0% secure contract using fuzzing before<00:00:20.279> we<00:00:20.580> start<00:00:20.760> just<00:00:21.060> to<00:00:21.240> get<00:00:21.300> like<00:00:21.480> a<00:00:21.600> sense 00:00:21.830 --> 00:00:21.840 align:start position:0% before we start just to get like a sense 00:00:21.840 --> 00:00:24.349 align:start position:0% before we start just to get like a sense how<00:00:22.439> many<00:00:22.560> of<00:00:22.800> you<00:00:23.039> have<00:00:23.340> used<00:00:23.640> the<00:00:23.820> kidney<00:00:24.240> in 00:00:24.349 --> 00:00:24.359 align:start position:0% how many of you have used the kidney in 00:00:24.359 --> 00:00:26.689 align:start position:0% how many of you have used the kidney in the<00:00:24.480> past 00:00:26.689 --> 00:00:26.699 align:start position:0% 00:00:26.699 --> 00:00:29.450 align:start position:0% echidna<00:00:27.840> it's<00:00:28.320> a<00:00:28.500> what<00:00:29.099> we're<00:00:29.220> going<00:00:29.400> to 00:00:29.450 --> 00:00:29.460 align:start position:0% echidna it's a what we're going to 00:00:29.460 --> 00:00:31.009 align:start position:0% echidna it's a what we're going to present 00:00:31.009 --> 00:00:31.019 align:start position:0% present 00:00:31.019 --> 00:00:33.729 align:start position:0% present okay 00:00:33.729 --> 00:00:33.739 align:start position:0% 00:00:33.739 --> 00:00:37.310 align:start position:0% okay<00:00:34.739> so<00:00:35.040> who<00:00:35.219> are<00:00:35.399> we<00:00:35.579> so<00:00:35.760> Gustavo<00:00:36.360> Greco<00:00:36.960> and 00:00:37.310 --> 00:00:37.320 align:start position:0% okay so who are we so Gustavo Greco and 00:00:37.320 --> 00:00:39.229 align:start position:0% okay so who are we so Gustavo Greco and myself<00:00:37.440> Rosner<00:00:38.040> Feist<00:00:38.340> we<00:00:38.700> are<00:00:38.820> both<00:00:39.000> security 00:00:39.229 --> 00:00:39.239 align:start position:0% myself Rosner Feist we are both security 00:00:39.239 --> 00:00:41.569 align:start position:0% myself Rosner Feist we are both security researcher<00:00:39.960> at<00:00:40.200> trail<00:00:40.320> of<00:00:40.559> Beats<00:00:40.920> if<00:00:41.460> you 00:00:41.569 --> 00:00:41.579 align:start position:0% researcher at trail of Beats if you 00:00:41.579 --> 00:00:43.729 align:start position:0% researcher at trail of Beats if you don't<00:00:41.700> know<00:00:41.940> us<00:00:42.180> we<00:00:42.840> are<00:00:42.960> a<00:00:43.079> company<00:00:43.200> where<00:00:43.559> we 00:00:43.729 --> 00:00:43.739 align:start position:0% don't know us we are a company where we 00:00:43.739 --> 00:00:44.990 align:start position:0% don't know us we are a company where we specialize<00:00:44.100> in<00:00:44.280> high<00:00:44.520> hand<00:00:44.820> security 00:00:44.990 --> 00:00:45.000 align:start position:0% specialize in high hand security 00:00:45.000 --> 00:00:47.090 align:start position:0% specialize in high hand security technology<00:00:45.600> we<00:00:46.440> have<00:00:46.559> expertive<00:00:46.980> in 00:00:47.090 --> 00:00:47.100 align:start position:0% technology we have expertive in 00:00:47.100 --> 00:00:48.830 align:start position:0% technology we have expertive in blockchain<00:00:47.460> but<00:00:47.760> also<00:00:48.000> another<00:00:48.180> topic<00:00:48.660> for 00:00:48.830 --> 00:00:48.840 align:start position:0% blockchain but also another topic for 00:00:48.840 --> 00:00:50.569 align:start position:0% blockchain but also another topic for example<00:00:49.079> we<00:00:49.320> do<00:00:49.500> a<00:00:49.620> lot<00:00:49.739> of<00:00:49.860> cloud<00:00:50.280> native 00:00:50.569 --> 00:00:50.579 align:start position:0% example we do a lot of cloud native 00:00:50.579 --> 00:00:52.069 align:start position:0% example we do a lot of cloud native application<00:00:51.120> or<00:00:51.480> we<00:00:51.600> do<00:00:51.780> a<00:00:51.899> lot<00:00:52.020> of 00:00:52.069 --> 00:00:52.079 align:start position:0% application or we do a lot of 00:00:52.079 --> 00:00:54.170 align:start position:0% application or we do a lot of cryptography<00:00:52.800> with<00:00:53.039> like<00:00:53.219> weaker<00:00:53.760> stuff<00:00:53.940> and 00:00:54.170 --> 00:00:54.180 align:start position:0% cryptography with like weaker stuff and 00:00:54.180 --> 00:00:57.110 align:start position:0% cryptography with like weaker stuff and so<00:00:54.480> something<00:00:55.320> that<00:00:55.739> I<00:00:56.039> think<00:00:56.219> differs<00:00:56.760> from 00:00:57.110 --> 00:00:57.120 align:start position:0% so something that I think differs from 00:00:57.120 --> 00:00:59.150 align:start position:0% so something that I think differs from other<00:00:57.360> company<00:00:57.780> is<00:00:58.199> that<00:00:58.440> we<00:00:58.559> spend<00:00:58.860> a<00:00:58.980> lot<00:00:59.039> of 00:00:59.150 --> 00:00:59.160 align:start position:0% other company is that we spend a lot of 00:00:59.160 --> 00:01:01.310 align:start position:0% other company is that we spend a lot of time<00:00:59.399> trying<00:01:00.059> to<00:01:00.300> apply<00:01:00.660> research<00:01:01.199> and 00:01:01.310 --> 00:01:01.320 align:start position:0% time trying to apply research and 00:01:01.320 --> 00:01:03.290 align:start position:0% time trying to apply research and program<00:01:01.559> analysis<00:01:02.100> into<00:01:02.340> like<00:01:02.640> our<00:01:02.820> daily<00:01:03.000> job 00:01:03.290 --> 00:01:03.300 align:start position:0% program analysis into like our daily job 00:01:03.300 --> 00:01:05.750 align:start position:0% program analysis into like our daily job as<00:01:04.019> a<00:01:04.140> result<00:01:04.260> we<00:01:04.619> have<00:01:04.739> built<00:01:05.100> a<00:01:05.280> lot<00:01:05.400> of<00:01:05.580> Open 00:01:05.750 --> 00:01:05.760 align:start position:0% as a result we have built a lot of Open 00:01:05.760 --> 00:01:08.149 align:start position:0% as a result we have built a lot of Open Source<00:01:06.180> tool<00:01:06.479> you<00:01:07.140> might<00:01:07.260> know<00:01:07.439> slitter<00:01:07.860> which 00:01:08.149 --> 00:01:08.159 align:start position:0% Source tool you might know slitter which 00:01:08.159 --> 00:01:10.190 align:start position:0% Source tool you might know slitter which is<00:01:08.280> a<00:01:08.400> static<00:01:08.700> analyzer<00:01:09.119> for<00:01:09.299> solidity<00:01:09.780> a 00:01:10.190 --> 00:01:10.200 align:start position:0% is a static analyzer for solidity a 00:01:10.200 --> 00:01:12.230 align:start position:0% is a static analyzer for solidity a kidnap<00:01:10.619> we<00:01:11.400> are<00:01:11.520> going<00:01:11.640> to<00:01:11.760> talk<00:01:11.880> about<00:01:12.000> it 00:01:12.230 --> 00:01:12.240 align:start position:0% kidnap we are going to talk about it 00:01:12.240 --> 00:01:14.450 align:start position:0% kidnap we are going to talk about it today<00:01:12.479> but<00:01:13.320> we<00:01:13.500> have<00:01:13.619> a<00:01:13.740> lot<00:01:13.799> of<00:01:13.920> other<00:01:14.040> tools 00:01:14.450 --> 00:01:14.460 align:start position:0% today but we have a lot of other tools 00:01:14.460 --> 00:01:15.830 align:start position:0% today but we have a lot of other tools for<00:01:14.520> example<00:01:14.700> tiller<00:01:15.240> which<00:01:15.420> is<00:01:15.479> a<00:01:15.600> static 00:01:15.830 --> 00:01:15.840 align:start position:0% for example tiller which is a static 00:01:15.840 --> 00:01:18.289 align:start position:0% for example tiller which is a static analyzer<00:01:16.320> for<00:01:16.500> algorand<00:01:17.060> armana<00:01:18.060> which<00:01:18.180> is 00:01:18.289 --> 00:01:18.299 align:start position:0% analyzer for algorand armana which is 00:01:18.299 --> 00:01:20.990 align:start position:0% analyzer for algorand armana which is static<00:01:18.600> analyzer<00:01:19.020> for<00:01:19.200> KO<00:01:19.619> and<00:01:19.860> so<00:01:19.979> on 00:01:20.990 --> 00:01:21.000 align:start position:0% static analyzer for KO and so on 00:01:21.000 --> 00:01:24.050 align:start position:0% static analyzer for KO and so on four<00:01:21.840> techniques<00:01:22.439> the<00:01:23.220> first<00:01:23.340> one<00:01:23.580> is<00:01:23.759> using 00:01:24.050 --> 00:01:24.060 align:start position:0% four techniques the first one is using 00:01:24.060 --> 00:01:26.330 align:start position:0% four techniques the first one is using unit<00:01:24.299> test<00:01:24.659> the<00:01:25.140> second<00:01:25.320> one<00:01:25.560> is<00:01:25.740> using<00:01:26.040> manual 00:01:26.330 --> 00:01:26.340 align:start position:0% unit test the second one is using manual 00:01:26.340 --> 00:01:28.969 align:start position:0% unit test the second one is using manual review<00:01:26.720> and<00:01:27.720> the<00:01:27.960> two<00:01:28.080> last<00:01:28.380> technique<00:01:28.740> are 00:01:28.969 --> 00:01:28.979 align:start position:0% review and the two last technique are 00:01:28.979 --> 00:01:31.130 align:start position:0% review and the two last technique are using<00:01:29.340> fully<00:01:29.700> automated<00:01:30.060> or<00:01:30.360> semi-automated 00:01:31.130 --> 00:01:31.140 align:start position:0% using fully automated or semi-automated 00:01:31.140 --> 00:01:33.830 align:start position:0% using fully automated or semi-automated technique 00:01:33.830 --> 00:01:33.840 align:start position:0% 00:01:33.840 --> 00:01:36.469 align:start position:0% I'm<00:01:34.320> assuming<00:01:34.799> everyone<00:01:35.520> here<00:01:35.939> is<00:01:36.180> familiar 00:01:36.469 --> 00:01:36.479 align:start position:0% I'm assuming everyone here is familiar 00:01:36.479 --> 00:01:38.870 align:start position:0% I'm assuming everyone here is familiar with<00:01:36.720> unit<00:01:36.900> tests<00:01:37.439> you<00:01:37.979> should<00:01:38.159> use<00:01:38.340> any<00:01:38.579> test 00:01:38.870 --> 00:01:38.880 align:start position:0% with unit tests you should use any test 00:01:38.880 --> 00:01:41.870 align:start position:0% with unit tests you should use any test and<00:01:39.240> they<00:01:39.360> are<00:01:39.540> good<00:01:39.720> usually<00:01:40.079> to<00:01:40.439> cover<00:01:40.880> that 00:01:41.870 --> 00:01:41.880 align:start position:0% and they are good usually to cover that 00:01:41.880 --> 00:01:44.270 align:start position:0% and they are good usually to cover that the<00:01:42.119> system<00:01:42.420> is<00:01:42.780> working<00:01:42.960> as<00:01:43.320> expected<00:01:43.799> in<00:01:44.159> the 00:01:44.270 --> 00:01:44.280 align:start position:0% the system is working as expected in the 00:01:44.280 --> 00:01:46.550 align:start position:0% the system is working as expected in the happy<00:01:44.520> path<00:01:45.420> something<00:01:45.900> that<00:01:46.200> we<00:01:46.380> have 00:01:46.550 --> 00:01:46.560 align:start position:0% happy path something that we have 00:01:46.560 --> 00:01:49.130 align:start position:0% happy path something that we have learned<00:01:46.979> over<00:01:47.460> our<00:01:47.700> audit<00:01:48.119> and<00:01:48.299> I<00:01:48.600> know<00:01:48.840> those 00:01:49.130 --> 00:01:49.140 align:start position:0% learned over our audit and I know those 00:01:49.140 --> 00:01:51.710 align:start position:0% learned over our audit and I know those analysis<00:01:49.979> that<00:01:50.159> we<00:01:50.340> have<00:01:50.460> done<00:01:50.640> is<00:01:51.240> that<00:01:51.479> there 00:01:51.710 --> 00:01:51.720 align:start position:0% analysis that we have done is that there 00:01:51.720 --> 00:01:54.590 align:start position:0% analysis that we have done is that there is<00:01:51.899> no<00:01:52.079> correlation<00:01:52.799> between<00:01:53.460> the<00:01:54.240> quality 00:01:54.590 --> 00:01:54.600 align:start position:0% is no correlation between the quality 00:01:54.600 --> 00:01:56.149 align:start position:0% is no correlation between the quality and<00:01:54.780> the<00:01:54.899> quantity<00:01:55.140> of<00:01:55.320> the<00:01:55.439> unit<00:01:55.560> test<00:01:55.860> and 00:01:56.149 --> 00:01:56.159 align:start position:0% and the quantity of the unit test and 00:01:56.159 --> 00:01:58.490 align:start position:0% and the quantity of the unit test and the<00:01:56.280> likelihood<00:01:56.820> of<00:01:57.000> having<00:01:57.180> high<00:01:57.540> severity 00:01:58.490 --> 00:01:58.500 align:start position:0% the likelihood of having high severity 00:01:58.500 --> 00:02:00.889 align:start position:0% the likelihood of having high severity vulnerability<00:01:59.399> and<00:02:00.119> this<00:02:00.299> is<00:02:00.420> we<00:02:00.720> actually 00:02:00.889 --> 00:02:00.899 align:start position:0% vulnerability and this is we actually 00:02:00.899 --> 00:02:02.749 align:start position:0% vulnerability and this is we actually have<00:02:01.079> an<00:02:01.259> academic<00:02:01.619> paper<00:02:01.799> on<00:02:02.040> this<00:02:02.220> where<00:02:02.520> we 00:02:02.749 --> 00:02:02.759 align:start position:0% have an academic paper on this where we 00:02:02.759 --> 00:02:04.789 align:start position:0% have an academic paper on this where we have<00:02:02.939> looked<00:02:03.659> over<00:02:03.780> like<00:02:04.079> all<00:02:04.200> the<00:02:04.380> audits<00:02:04.680> we 00:02:04.789 --> 00:02:04.799 align:start position:0% have looked over like all the audits we 00:02:04.799 --> 00:02:06.709 align:start position:0% have looked over like all the audits we have<00:02:04.920> done<00:02:05.100> and<00:02:05.340> this<00:02:05.520> is<00:02:05.640> a<00:02:05.880> correlation<00:02:06.420> that 00:02:06.709 --> 00:02:06.719 align:start position:0% have done and this is a correlation that 00:02:06.719 --> 00:02:10.130 align:start position:0% have done and this is a correlation that we<00:02:06.840> have<00:02:07.020> not<00:02:07.140> found<00:02:07.459> and<00:02:08.459> the<00:02:08.759> reason<00:02:08.940> why<00:02:09.420> our 00:02:10.130 --> 00:02:10.140 align:start position:0% we have not found and the reason why our 00:02:10.140 --> 00:02:11.990 align:start position:0% we have not found and the reason why our intuition<00:02:10.619> tell<00:02:10.920> us<00:02:11.099> that<00:02:11.340> when<00:02:11.760> you<00:02:11.879> are 00:02:11.990 --> 00:02:12.000 align:start position:0% intuition tell us that when you are 00:02:12.000 --> 00:02:13.369 align:start position:0% intuition tell us that when you are going<00:02:12.120> to<00:02:12.180> write<00:02:12.480> unit<00:02:12.720> test<00:02:12.959> you<00:02:13.140> are<00:02:13.260> going 00:02:13.369 --> 00:02:13.379 align:start position:0% going to write unit test you are going 00:02:13.379 --> 00:02:16.010 align:start position:0% going to write unit test you are going to<00:02:13.500> try<00:02:13.739> to<00:02:13.980> cover<00:02:14.160> happy<00:02:14.640> path<00:02:15.000> things<00:02:15.660> that 00:02:16.010 --> 00:02:16.020 align:start position:0% to try to cover happy path things that 00:02:16.020 --> 00:02:17.630 align:start position:0% to try to cover happy path things that are<00:02:16.200> supposed<00:02:16.440> to<00:02:16.680> do<00:02:16.800> in<00:02:16.980> the<00:02:17.099> correct 00:02:17.630 --> 00:02:17.640 align:start position:0% are supposed to do in the correct 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--> 00:02:29.819 align:start position:0% an example of a unit test the second 00:02:29.819 --> 00:02:31.309 align:start position:0% an example of a unit test the second technique<00:02:30.180> that<00:02:30.360> you<00:02:30.540> can<00:02:30.599> use<00:02:30.840> is<00:02:31.080> manual 00:02:31.309 --> 00:02:31.319 align:start position:0% technique that you can use is manual 00:02:31.319 --> 00:02:33.710 align:start position:0% technique that you can use is manual webview<00:02:31.800> so<00:02:32.040> you<00:02:32.340> can<00:02:32.400> go<00:02:32.520> line<00:02:32.879> by<00:02:33.060> line<00:02:33.300> and 00:02:33.710 --> 00:02:33.720 align:start position:0% webview so you can go line by line and 00:02:33.720 --> 00:02:35.210 align:start position:0% webview so you can go line by line and try<00:02:33.900> to<00:02:34.020> understand<00:02:34.200> what<00:02:34.680> the<00:02:34.800> code<00:02:34.980> is 00:02:35.210 --> 00:02:35.220 align:start position:0% try to understand what the code is 00:02:35.220 --> 00:02:36.949 align:start position:0% try to understand what the code is supposed<00:02:35.400> to<00:02:35.640> do<00:02:35.819> what<00:02:36.239> is<00:02:36.480> actually<00:02:36.720> doing 00:02:36.949 --> 00:02:36.959 align:start position:0% supposed to do what is actually doing 00:02:36.959 --> 00:02:38.390 align:start position:0% supposed to do what is actually doing and<00:02:37.379> if<00:02:37.560> there<00:02:37.680> is<00:02:37.860> like<00:02:37.980> a<00:02:38.160> difference 00:02:38.390 --> 00:02:38.400 align:start position:0% and if there is like a difference 00:02:38.400 --> 00:02:40.930 align:start position:0% and if there is like a difference between<00:02:38.879> both<00:02:39.180> doing<00:02:40.080> manual<00:02:40.620> review 00:02:40.930 --> 00:02:40.940 align:start position:0% between both doing manual review 00:02:40.940 --> 00:02:43.430 align:start position:0% between both doing manual review requires<00:02:41.940> specific<00:02:42.239> set<00:02:42.480> of<00:02:42.660> skills<00:02:43.140> it's 00:02:43.430 --> 00:02:43.440 align:start position:0% requires specific set of skills it's 00:02:43.440 --> 00:02:45.949 align:start position:0% requires specific set of skills it's time<00:02:43.680> consuming<00:02:44.220> it's<00:02:44.640> it's<00:02:45.060> it's<00:02:45.239> kind<00:02:45.900> of 00:02:45.949 --> 00:02:45.959 align:start position:0% time consuming it's it's it's kind of 00:02:45.959 --> 00:02:48.589 align:start position:0% time consuming it's it's it's kind of difficult<00:02:46.319> to<00:02:46.500> do<00:02:46.760> usually<00:02:47.760> you<00:02:48.239> are<00:02:48.360> going<00:02:48.480> to 00:02:48.589 --> 00:02:48.599 align:start position:0% difficult to do usually you are going to 00:02:48.599 --> 00:02:50.210 align:start position:0% difficult to do usually you are going to go<00:02:48.780> through<00:02:48.959> a<00:02:49.140> security<00:02:49.200> company<00:02:49.620> to<00:02:49.920> do<00:02:50.099> a 00:02:50.210 --> 00:02:50.220 align:start position:0% go through a security company to do a 00:02:50.220 --> 00:02:51.830 align:start position:0% go through a security company to do a security<00:02:50.340> assessment<00:02:51.300> um<00:02:51.300> to<00:02:51.540> have<00:02:51.660> people 00:02:51.830 --> 00:02:51.840 align:start position:0% security assessment um to have people 00:02:51.840 --> 00:02:55.430 align:start position:0% security assessment um to have people that<00:02:52.080> have<00:02:52.200> this<00:02:52.379> specific<00:02:52.680> set<00:02:52.860> of<00:02:53.040> skills 00:02:55.430 --> 00:02:55.440 align:start position:0% that have this specific set of skills 00:02:55.440 --> 00:02:57.710 align:start position:0% that have this specific set of skills the<00:02:56.099> next<00:02:56.280> technique<00:02:56.640> that<00:02:56.819> you<00:02:57.000> can<00:02:57.120> use<00:02:57.300> is 00:02:57.710 --> 00:02:57.720 align:start position:0% the next technique that you can use is 00:02:57.720 --> 00:03:00.229 align:start position:0% the next technique that you can use is using<00:02:58.080> a<00:02:58.260> fully<00:02:58.500> automated<00:02:58.860> tool<00:02:59.400> these<00:03:00.180> are 00:03:00.229 --> 00:03:00.239 align:start position:0% using a fully automated tool these are 00:03:00.239 --> 00:03:03.170 align:start position:0% using a fully automated tool these are like<00:03:00.360> the<00:03:00.599> two<00:03:00.780> that<00:03:01.019> are<00:03:01.200> going<00:03:01.620> to<00:03:01.860> find<00:03:02.220> some 00:03:03.170 --> 00:03:03.180 align:start position:0% like the two that are going to find some 00:03:03.180 --> 00:03:04.970 align:start position:0% like the two that are going to find some of<00:03:03.300> the<00:03:03.480> common<00:03:03.599> bugs<00:03:04.080> you're<00:03:04.379> just<00:03:04.620> going<00:03:04.800> to 00:03:04.970 --> 00:03:04.980 align:start position:0% of the common bugs you're just going to 00:03:04.980 --> 00:03:06.470 align:start position:0% of the common bugs you're just going to click<00:03:05.280> on<00:03:05.340> the<00:03:05.519> button<00:03:05.760> and<00:03:06.060> the<00:03:06.180> tool<00:03:06.420> is 00:03:06.470 --> 00:03:06.480 align:start position:0% click on the button and the tool is 00:03:06.480 --> 00:03:07.790 align:start position:0% click on the button and the tool is going<00:03:06.599> to<00:03:06.720> tell<00:03:06.840> you<00:03:06.959> there<00:03:07.260> is<00:03:07.440> this<00:03:07.560> type<00:03:07.680> of 00:03:07.790 --> 00:03:07.800 align:start position:0% going to tell you there is this type of 00:03:07.800 --> 00:03:10.070 align:start position:0% going to tell you there is this type of work<00:03:07.980> or<00:03:08.280> not<00:03:08.459> for<00:03:09.420> example<00:03:09.660> you<00:03:09.840> might<00:03:09.959> know 00:03:10.070 --> 00:03:10.080 align:start position:0% work or not for example you might know 00:03:10.080 --> 00:03:11.930 align:start position:0% work or not for example you might know Theta<00:03:10.500> which<00:03:10.680> is<00:03:10.800> our<00:03:10.920> static<00:03:11.400> analyzer<00:03:11.819> for 00:03:11.930 --> 00:03:11.940 align:start position:0% Theta which is our static analyzer for 00:03:11.940 --> 00:03:14.210 align:start position:0% Theta which is our static analyzer for solidity<00:03:12.480> this<00:03:13.140> type<00:03:13.319> of<00:03:13.500> techniques<00:03:13.980> might 00:03:14.210 --> 00:03:14.220 align:start position:0% solidity this type of techniques might 00:03:14.220 --> 00:03:15.949 align:start position:0% solidity this type of techniques might give<00:03:14.459> you<00:03:14.580> forth<00:03:15.060> running 00:03:15.949 --> 00:03:15.959 align:start position:0% give you forth running 00:03:15.959 --> 00:03:17.750 align:start position:0% give you forth running um<00:03:16.019> but<00:03:16.739> they're<00:03:17.040> also<00:03:17.220> really<00:03:17.340> powerful 00:03:17.750 --> 00:03:17.760 align:start position:0% um but they're also really powerful 00:03:17.760 --> 00:03:19.610 align:start position:0% um but they're also really powerful because<00:03:18.000> I<00:03:18.360> might<00:03:18.540> cut<00:03:18.720> you<00:03:18.900> know<00:03:19.080> like<00:03:19.319> a 00:03:19.610 --> 00:03:19.620 align:start position:0% because I might cut you know like a 00:03:19.620 --> 00:03:21.470 align:start position:0% because I might cut you know like a critical<00:03:20.159> bugs 00:03:21.470 --> 00:03:21.480 align:start position:0% critical bugs 00:03:21.480 --> 00:03:22.910 align:start position:0% critical bugs you 00:03:22.910 --> 00:03:22.920 align:start position:0% you 00:03:22.920 --> 00:03:24.290 align:start position:0% you oh<00:03:23.400> yeah 00:03:24.290 --> 00:03:24.300 align:start position:0% oh yeah 00:03:24.300 --> 00:03:33.649 align:start position:0% oh yeah okay 00:03:33.649 --> 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uh there is a triage<00:03:40.019> mode<00:03:40.319> so<00:03:40.560> once<00:03:40.920> you<00:03:40.980> have<00:03:41.040> triage<00:03:41.400> like 00:03:41.630 --> 00:03:41.640 align:start position:0% triage mode so once you have triage like 00:03:41.640 --> 00:03:43.369 align:start position:0% triage mode so once you have triage like the<00:03:41.760> ways<00:03:42.000> you<00:03:42.120> as<00:03:42.360> I<00:03:42.540> won't<00:03:42.659> show<00:03:42.840> up<00:03:42.959> like<00:03:43.200> in 00:03:43.369 --> 00:03:43.379 align:start position:0% the ways you as I won't show up like in 00:03:43.379 --> 00:03:45.949 align:start position:0% the ways you as I won't show up like in the<00:03:43.500> next<00:03:43.620> execution<00:03:44.180> and<00:03:45.180> if<00:03:45.540> it<00:03:45.659> takes<00:03:45.840> you 00:03:45.949 --> 00:03:45.959 align:start position:0% the next execution and if it takes you 00:03:45.959 --> 00:03:47.509 align:start position:0% the next execution and if it takes you like<00:03:46.200> one<00:03:46.319> hour<00:03:46.500> and<00:03:46.799> at<00:03:46.980> the<00:03:47.099> end<00:03:47.159> of<00:03:47.280> the<00:03:47.400> day 00:03:47.509 --> 00:03:47.519 align:start position:0% like one hour and at the end of the day 00:03:47.519 --> 00:03:49.430 align:start position:0% like one hour and at the end of the day you<00:03:47.940> might<00:03:48.360> be<00:03:48.540> able<00:03:48.659> to<00:03:48.780> catch<00:03:49.140> critical 00:03:49.430 --> 00:03:49.440 align:start position:0% you might be able to catch critical 00:03:49.440 --> 00:03:51.470 align:start position:0% you might be able to catch critical vulnerability<00:03:50.099> I<00:03:50.940> would<00:03:51.060> say<00:03:51.180> it's<00:03:51.299> worth 00:03:51.470 --> 00:03:51.480 align:start position:0% vulnerability I would say it's worth 00:03:51.480 --> 00:03:53.690 align:start position:0% vulnerability I would say it's worth going<00:03:51.780> for<00:03:51.959> the<00:03:52.080> first<00:03:52.140> result 00:03:53.690 --> 00:03:53.700 align:start position:0% going for the first result 00:03:53.700 --> 00:03:56.089 align:start position:0% going for the first result and<00:03:54.299> look<00:03:54.480> we<00:03:54.900> are<00:03:55.200> we<00:03:55.379> have<00:03:55.560> like<00:03:55.680> a<00:03:55.799> list<00:03:55.920> of 00:03:56.089 --> 00:03:56.099 align:start position:0% and look we are we have like a list of 00:03:56.099 --> 00:03:58.250 align:start position:0% and look we are we have like a list of trophy<00:03:56.519> for<00:03:56.760> uh<00:03:57.000> Twitter<00:03:57.360> that<00:03:57.840> demonstrates 00:03:58.250 --> 00:03:58.260 align:start position:0% trophy for uh Twitter that demonstrates 00:03:58.260 --> 00:04:00.530 align:start position:0% trophy for uh Twitter that demonstrates that<00:03:58.500> we<00:03:58.680> have<00:03:58.799> found<00:03:59.040> a<00:03:59.640> lot<00:03:59.819> of<00:04:00.000> like<00:04:00.239> actual 00:04:00.530 --> 00:04:00.540 align:start position:0% that we have found a lot of like actual 00:04:00.540 --> 00:04:02.750 align:start position:0% that we have found a lot of like actual bug<00:04:00.780> using<00:04:01.260> it<00:04:01.379> so<00:04:01.739> yeah<00:04:01.920> there<00:04:02.280> is<00:04:02.400> like<00:04:02.580> a 00:04:02.750 --> 00:04:02.760 align:start position:0% bug using it so yeah there is like a 00:04:02.760 --> 00:04:05.030 align:start position:0% bug using it so yeah there is like a false<00:04:03.180> positive<00:04:03.480> pass<00:04:03.720> for<00:04:04.080> for<00:04:04.500> false<00:04:04.860> alarm 00:04:05.030 --> 00:04:05.040 align:start position:0% false positive pass for for false alarm 00:04:05.040 --> 00:04:07.490 align:start position:0% false positive pass for for false alarm but<00:04:05.760> it's<00:04:06.420> not<00:04:06.599> going<00:04:06.780> to<00:04:06.840> take<00:04:07.019> you<00:04:07.200> so<00:04:07.379> much 00:04:07.490 --> 00:04:07.500 align:start position:0% but it's not going to take you so much 00:04:07.500 --> 00:04:09.410 align:start position:0% but it's not going to take you so much time<00:04:07.680> and<00:04:07.860> it's<00:04:07.980> going<00:04:08.159> to<00:04:08.280> provide<00:04:08.519> you<00:04:08.640> value 00:04:09.410 --> 00:04:09.420 align:start position:0% time and it's going to provide you value 00:04:09.420 --> 00:04:11.270 align:start position:0% time and it's going to provide you value for<00:04:09.900> example<00:04:10.140> we<00:04:10.379> have<00:04:10.439> a<00:04:10.560> git<00:04:10.739> abduction<00:04:11.040> with 00:04:11.270 --> 00:04:11.280 align:start position:0% for example we have a git abduction with 00:04:11.280 --> 00:04:13.729 align:start position:0% for example we have a git abduction with Filter<00:04:11.519> when<00:04:12.420> you<00:04:12.659> can<00:04:12.780> connect<00:04:12.959> it<00:04:13.200> to<00:04:13.379> GitHub 00:04:13.729 --> 00:04:13.739 align:start position:0% Filter when you can connect it to GitHub 00:04:13.739 --> 00:04:15.890 align:start position:0% Filter when you can connect it to GitHub on<00:04:14.459> every<00:04:14.580> pull<00:04:14.819> request<00:04:15.239> commitment 00:04:15.890 --> 00:04:15.900 align:start position:0% on every pull request commitment 00:04:15.900 --> 00:04:17.030 align:start position:0% on every pull request commitment depending<00:04:16.320> on<00:04:16.380> how<00:04:16.620> you<00:04:16.739> are<00:04:16.799> going<00:04:16.919> to 00:04:17.030 --> 00:04:17.040 align:start position:0% depending on how you are going to 00:04:17.040 --> 00:04:19.069 align:start position:0% depending on how you are going to configure<00:04:17.400> it<00:04:17.519> it's<00:04:17.880> going<00:04:18.060> to<00:04:18.180> run<00:04:18.419> if<00:04:18.660> to<00:04:18.900> see 00:04:19.069 --> 00:04:19.079 align:start position:0% configure it it's going to run if to see 00:04:19.079 --> 00:04:20.270 align:start position:0% configure it it's going to run if to see if<00:04:19.139> you<00:04:19.320> are<00:04:19.440> introducing<00:04:19.919> new<00:04:20.100> new 00:04:20.270 --> 00:04:20.280 align:start position:0% if you are introducing new new 00:04:20.280 --> 00:04:22.909 align:start position:0% if you are introducing new new vulnerability<00:04:20.880> yeah<00:04:21.720> perhaps<00:04:22.139> sorry<00:04:22.560> perfect 00:04:22.909 --> 00:04:22.919 align:start position:0% vulnerability yeah perhaps sorry perfect 00:04:22.919 --> 00:04:25.790 align:start position:0% vulnerability yeah perhaps sorry perfect perhaps<00:04:23.520> next<00:04:23.820> uh<00:04:24.300> Year<00:04:24.660> we<00:04:24.900> will<00:04:25.020> do<00:04:25.259> a 00:04:25.790 --> 00:04:25.800 align:start position:0% perhaps next uh Year we will do a 00:04:25.800 --> 00:04:28.249 align:start position:0% perhaps next uh Year we will do a slitter<00:04:26.460> workshop<00:04:27.000> on<00:04:27.240> you 00:04:28.249 --> 00:04:28.259 align:start position:0% slitter workshop on you 00:04:28.259 --> 00:04:32.629 align:start position:0% slitter workshop on you and<00:04:28.680> this<00:04:28.979> is<00:04:29.040> open<00:04:29.280> source<00:04:29.759> and<00:04:29.820> it's<00:04:30.000> free 00:04:32.629 --> 00:04:32.639 align:start position:0% 00:04:32.639 --> 00:04:35.390 align:start position:0% okay<00:04:33.000> the<00:04:33.419> last<00:04:33.720> technique<00:04:34.320> that<00:04:34.919> you<00:04:35.100> can<00:04:35.220> use 00:04:35.390 --> 00:04:35.400 align:start position:0% okay the last technique that you can use 00:04:35.400 --> 00:04:38.330 align:start position:0% okay the last technique that you can use is<00:04:35.880> using<00:04:36.300> semi-automated<00:04:37.139> analysis<00:04:37.800> so 00:04:38.330 --> 00:04:38.340 align:start position:0% is using semi-automated analysis so 00:04:38.340 --> 00:04:40.310 align:start position:0% is using semi-automated analysis so these<00:04:38.639> are<00:04:38.699> going<00:04:38.880> to<00:04:39.000> be<00:04:39.180> tools<00:04:39.720> for<00:04:40.139> which 00:04:40.310 --> 00:04:40.320 align:start position:0% these are going to be tools for which 00:04:40.320 --> 00:04:41.990 align:start position:0% these are going to be tools for which you<00:04:40.560> are<00:04:40.680> going<00:04:40.800> to<00:04:40.979> provide<00:04:41.759> some 00:04:41.990 --> 00:04:42.000 align:start position:0% you are going to provide some 00:04:42.000 --> 00:04:43.430 align:start position:0% you are going to provide some information<00:04:42.180> for<00:04:42.720> which<00:04:42.900> you<00:04:43.080> are<00:04:43.199> going<00:04:43.320> to 00:04:43.430 --> 00:04:43.440 align:start position:0% information for which you are going to 00:04:43.440 --> 00:04:46.550 align:start position:0% information for which you are going to have<00:04:43.919> a<00:04:44.160> human<00:04:44.419> intervention<00:04:45.419> to<00:04:45.780> explain<00:04:46.199> to 00:04:46.550 --> 00:04:46.560 align:start position:0% have a human intervention to explain to 00:04:46.560 --> 00:04:48.590 align:start position:0% have a human intervention to explain to the<00:04:46.740> tool<00:04:47.100> what<00:04:47.460> you<00:04:47.520> are<00:04:47.699> looking<00:04:47.820> for 00:04:48.590 --> 00:04:48.600 align:start position:0% the tool what you are looking for 00:04:48.600 --> 00:04:50.930 align:start position:0% the tool what you are looking for and<00:04:49.560> this<00:04:49.800> is<00:04:49.919> a<00:04:50.040> bit<00:04:50.100> more<00:04:50.280> difficult<00:04:50.580> to<00:04:50.820> use 00:04:50.930 --> 00:04:50.940 align:start position:0% and this is a bit more difficult to use 00:04:50.940 --> 00:04:52.370 align:start position:0% and this is a bit more difficult to use because<00:04:51.180> it<00:04:51.479> requires<00:04:51.960> like<00:04:52.199> this 00:04:52.370 --> 00:04:52.380 align:start position:0% because it requires like this 00:04:52.380 --> 00:04:54.770 align:start position:0% because it requires like this interaction<00:04:52.740> from<00:04:53.040> you<00:04:53.340> know<00:04:53.460> from<00:04:53.580> the<00:04:53.759> user 00:04:54.770 --> 00:04:54.780 align:start position:0% interaction from you know from the user 00:04:54.780 --> 00:04:56.210 align:start position:0% interaction from you know from the user it's<00:04:55.199> a<00:04:55.380> Technique<00:04:55.500> we<00:04:55.740> are<00:04:55.860> going<00:04:55.979> to<00:04:56.100> see 00:04:56.210 --> 00:04:56.220 align:start position:0% it's a Technique we are going to see 00:04:56.220 --> 00:04:57.890 align:start position:0% it's a Technique we are going to see today<00:04:56.460> with<00:04:56.759> property<00:04:57.120> by<00:04:57.360> testing<00:04:57.720> with 00:04:57.890 --> 00:04:57.900 align:start position:0% today with property by testing with 00:04:57.900 --> 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fuzzing so first thing is a 00:05:09.720 --> 00:05:11.450 align:start position:0% introduce fuzzing so first thing is a standard<00:05:10.080> program<00:05:10.259> analysis<00:05:10.860> technique<00:05:11.220> that 00:05:11.450 --> 00:05:11.460 align:start position:0% standard program analysis technique that 00:05:11.460 --> 00:05:13.810 align:start position:0% standard program analysis technique that is<00:05:11.580> used<00:05:11.820> a<00:05:12.419> lot<00:05:12.720> in<00:05:12.960> traditional<00:05:13.440> security 00:05:13.810 --> 00:05:13.820 align:start position:0% is used a lot in traditional security 00:05:13.820 --> 00:05:17.090 align:start position:0% is used a lot in traditional security the<00:05:14.820> idea<00:05:15.240> is<00:05:15.419> basically<00:05:15.780> you<00:05:16.500> provide<00:05:16.919> a 00:05:17.090 --> 00:05:17.100 align:start position:0% the idea is basically you provide a 00:05:17.100 --> 00:05:19.189 align:start position:0% the idea is basically you provide a one-time<00:05:17.460> input<00:05:17.820> to<00:05:18.240> the<00:05:18.419> program<00:05:18.660> and<00:05:19.080> you 00:05:19.189 --> 00:05:19.199 align:start position:0% one-time input to the program and you 00:05:19.199 --> 00:05:20.810 align:start position:0% one-time input to the program and you try<00:05:19.380> to<00:05:19.560> see<00:05:19.800> what's<00:05:20.100> what's<00:05:20.340> going<00:05:20.580> to<00:05:20.699> happen 00:05:20.810 --> 00:05:20.820 align:start position:0% try to see what's what's going to happen 00:05:20.820 --> 00:05:23.210 align:start position:0% try to see what's what's going to happen you<00:05:21.120> try<00:05:21.300> to<00:05:21.419> stress<00:05:21.960> this<00:05:22.139> with<00:05:22.500> random<00:05:22.800> input 00:05:23.210 --> 00:05:23.220 align:start position:0% you try to stress this with random input 00:05:23.220 --> 00:05:26.390 align:start position:0% you try to stress this with random input the<00:05:24.000> most<00:05:24.240> trivial<00:05:25.139> uh<00:05:25.740> further<00:05:26.100> that<00:05:26.280> you 00:05:26.390 --> 00:05:26.400 align:start position:0% the most trivial uh further that you 00:05:26.400 --> 00:05:28.850 align:start position:0% the most trivial uh further that you convert<00:05:26.759> you<00:05:27.060> just<00:05:27.240> go<00:05:27.780> on<00:05:27.960> your<00:05:28.139> keyboard<00:05:28.380> and 00:05:28.850 --> 00:05:28.860 align:start position:0% convert you just go on your keyboard and 00:05:28.860 --> 00:05:30.890 align:start position:0% convert you just go on your keyboard and you<00:05:29.100> know<00:05:29.220> you<00:05:29.520> patch<00:05:29.940> random<00:05:30.240> bottom<00:05:30.600> and<00:05:30.720> you 00:05:30.890 --> 00:05:30.900 align:start position:0% you know you patch random bottom and you 00:05:30.900 --> 00:05:32.270 align:start position:0% you know you patch random bottom and you see<00:05:31.020> what's<00:05:31.440> going<00:05:31.620> to<00:05:31.740> happen<00:05:31.919> on<00:05:32.160> your 00:05:32.270 --> 00:05:32.280 align:start position:0% see what's going to happen on your 00:05:32.280 --> 00:05:33.650 align:start position:0% see what's going to happen on your program 00:05:33.650 --> 00:05:33.660 align:start position:0% program 00:05:33.660 --> 00:05:35.029 align:start position:0% program um again<00:05:33.960> it's<00:05:34.199> well<00:05:34.380> established<00:05:34.919> in 00:05:35.029 --> 00:05:35.039 align:start position:0% um again it's well established in 00:05:35.039 --> 00:05:36.469 align:start position:0% um again it's well established in traditional<00:05:35.460> security<00:05:35.639> we<00:05:36.120> have<00:05:36.180> a<00:05:36.300> lot<00:05:36.360> of 00:05:36.469 --> 00:05:36.479 align:start position:0% traditional security we have a lot of 00:05:36.479 --> 00:05:40.790 align:start position:0% traditional security we have a lot of tool<00:05:36.840> if<00:05:37.259> further<00:05:37.979> go<00:05:38.220> further<00:05:38.580> and<00:05:38.759> so<00:05:38.880> on 00:05:40.790 --> 00:05:40.800 align:start position:0% tool if further go further and so on 00:05:40.800 --> 00:05:43.490 align:start position:0% tool if further go further and so on however<00:05:41.460> most<00:05:41.940> of<00:05:42.240> the<00:05:42.360> traditional<00:05:43.080> feather 00:05:43.490 --> 00:05:43.500 align:start position:0% however most of the traditional feather 00:05:43.500 --> 00:05:45.890 align:start position:0% however most of the traditional feather are<00:05:43.860> going<00:05:44.100> to<00:05:44.340> look<00:05:44.520> for<00:05:44.880> memory<00:05:45.360> corruption 00:05:45.890 --> 00:05:45.900 align:start position:0% are going to look for memory corruption 00:05:45.900 --> 00:05:48.290 align:start position:0% are going to look for memory corruption for<00:05:46.259> crash<00:05:46.740> in<00:05:46.919> the<00:05:47.100> program 00:05:48.290 --> 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position:0% not that common what we are going to try 00:05:54.060 --> 00:05:57.170 align:start position:0% not that common what we are going to try to<00:05:54.300> look<00:05:54.539> for<00:05:54.780> is<00:05:55.500> a<00:05:56.280> property<00:05:56.699> of<00:05:56.820> the<00:05:57.000> system 00:05:57.170 --> 00:05:57.180 align:start position:0% to look for is a property of the system 00:05:57.180 --> 00:05:59.749 align:start position:0% to look for is a property of the system that<00:05:57.479> can<00:05:57.600> be<00:05:57.720> broken<00:05:58.100> and<00:05:59.100> this<00:05:59.280> is<00:05:59.340> why<00:05:59.580> we 00:05:59.749 --> 00:05:59.759 align:start position:0% that can be broken and this is why we 00:05:59.759 --> 00:06:02.210 align:start position:0% that can be broken and this is why we call<00:05:59.880> it<00:06:00.060> property<00:06:00.479> based<00:06:01.020> testing<00:06:01.320> basically 00:06:02.210 --> 00:06:02.220 align:start position:0% call it property based testing basically 00:06:02.220 --> 00:06:03.770 align:start position:0% call it property based testing basically the<00:06:02.460> way<00:06:02.639> it<00:06:02.759> works<00:06:03.000> is<00:06:03.060> that<00:06:03.240> the<00:06:03.419> user<00:06:03.660> is 00:06:03.770 --> 00:06:03.780 align:start position:0% the way it works is that the user is 00:06:03.780 --> 00:06:06.650 align:start position:0% the way it works is that the user is going<00:06:03.960> to<00:06:04.080> define<00:06:04.259> invariants<00:06:05.360> the<00:06:06.360> further 00:06:06.650 --> 00:06:06.660 align:start position:0% going to define invariants the further 00:06:06.660 --> 00:06:09.110 align:start position:0% going to define invariants the further is<00:06:06.900> going<00:06:07.080> to<00:06:07.259> explore<00:06:08.220> one<00:06:08.460> Dome<00:06:08.699> is<00:06:08.940> a 00:06:09.110 --> 00:06:09.120 align:start position:0% is going to explore one Dome is a 00:06:09.120 --> 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unit<00:06:16.740> tests<00:06:17.280> on<00:06:17.400> steroid<00:06:17.820> well<00:06:18.479> with 00:06:18.770 --> 00:06:18.780 align:start position:0% as like unit tests on steroid well with 00:06:18.780 --> 00:06:21.110 align:start position:0% as like unit tests on steroid well with unit<00:06:18.960> test<00:06:19.199> you<00:06:19.620> try<00:06:19.860> one<00:06:20.580> specific<00:06:20.880> value 00:06:21.110 --> 00:06:21.120 align:start position:0% unit test you try one specific value 00:06:21.120 --> 00:06:23.270 align:start position:0% unit test you try one specific value with<00:06:21.479> the<00:06:21.660> program<00:06:21.780> while<00:06:22.620> first<00:06:22.919> thing<00:06:23.160> is 00:06:23.270 --> 00:06:23.280 align:start position:0% with the program while first thing is 00:06:23.280 --> 00:06:24.830 align:start position:0% with the program while first thing is just<00:06:23.460> going<00:06:23.580> to<00:06:23.759> try<00:06:23.940> randomly<00:06:24.419> a<00:06:24.660> lot<00:06:24.720> of 00:06:24.830 --> 00:06:24.840 align:start position:0% just going to try randomly a lot of 00:06:24.840 --> 00:06:29.270 align:start position:0% just going to try randomly a lot of different<00:06:24.960> value 00:06:29.270 --> 00:06:29.280 align:start position:0% 00:06:29.280 --> 00:06:31.189 align:start position:0% I've<00:06:29.639> been<00:06:29.819> talking<00:06:29.940> a<00:06:30.180> lot<00:06:30.240> about<00:06:30.419> invariance 00:06:31.189 --> 00:06:31.199 align:start position:0% I've been talking a lot about invariance 00:06:31.199 --> 00:06:33.290 align:start position:0% I've been talking a lot about invariance or<00:06:31.440> what<00:06:31.860> an<00:06:31.979> invariant<00:06:32.400> an<00:06:32.639> invariant<00:06:33.120> is 00:06:33.290 --> 00:06:33.300 align:start position:0% or what an invariant an invariant is 00:06:33.300 --> 00:06:35.090 align:start position:0% or what an invariant an invariant is something<00:06:33.539> within<00:06:34.080> your<00:06:34.259> system<00:06:34.500> that<00:06:34.860> should 00:06:35.090 --> 00:06:35.100 align:start position:0% something within your system that should 00:06:35.100 --> 00:06:37.010 align:start position:0% something within your system that should always<00:06:35.340> be<00:06:35.699> true<00:06:35.880> it's<00:06:36.479> something<00:06:36.660> that 00:06:37.010 --> 00:06:37.020 align:start position:0% always be true it's something that 00:06:37.020 --> 00:06:39.469 align:start position:0% always be true it's something that should<00:06:37.319> never<00:06:37.520> be<00:06:38.520> false<00:06:38.819> or<00:06:39.000> that<00:06:39.300> should 00:06:39.469 --> 00:06:39.479 align:start position:0% should never be false or that should 00:06:39.479 --> 00:06:41.870 align:start position:0% should never be false or that should never<00:06:39.660> be<00:06:40.139> not<00:06:40.620> possible<00:06:40.979> to<00:06:41.220> check<00:06:41.400> if<00:06:41.699> it's 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been<00:06:53.039> using<00:06:53.340> it<00:06:53.520> for 00:06:53.930 --> 00:06:53.940 align:start position:0% interpensers we have been using it for 00:06:53.940 --> 00:06:56.570 align:start position:0% interpensers we have been using it for like<00:06:54.300> four<00:06:54.720> or<00:06:54.960> five<00:06:55.199> years<00:06:55.319> even<00:06:55.680> now<00:06:55.919> uh<00:06:56.400> in 00:06:56.570 --> 00:06:56.580 align:start position:0% like four or five years even now uh in 00:06:56.580 --> 00:06:59.270 align:start position:0% like four or five years even now uh in all<00:06:56.699> our<00:06:56.880> audits<00:06:57.300> you<00:06:57.840> can<00:06:57.960> see<00:06:58.139> a<00:06:58.319> list<00:06:58.500> of<00:06:58.740> uh 00:06:59.270 --> 00:06:59.280 align:start position:0% all our audits you can see a list of uh 00:06:59.280 --> 00:07:01.249 align:start position:0% all our audits you can see a list of uh match<00:06:59.460> your<00:06:59.699> code<00:06:59.940> base<00:07:00.120> actually<00:07:00.479> using<00:07:01.020> and 00:07:01.249 --> 00:07:01.259 align:start position:0% match your code base actually using and 00:07:01.259 --> 00:07:04.189 align:start position:0% match your code base actually using and I've<00:07:01.440> integrated<00:07:01.919> Echidna<00:07:02.520> in<00:07:02.759> their<00:07:02.880> process 00:07:04.189 --> 00:07:04.199 align:start position:0% I've integrated Echidna in their process 00:07:04.199 --> 00:07:06.890 align:start position:0% I've integrated Echidna in their process for<00:07:04.560> Aquino<00:07:04.919> we<00:07:05.160> are<00:07:05.340> focusing<00:07:05.759> on<00:07:06.240> the<00:07:06.539> you 00:07:06.890 --> 00:07:06.900 align:start position:0% for Aquino we are focusing on the you 00:07:06.900 --> 00:07:09.409 align:start position:0% for Aquino we are focusing on the you know<00:07:07.020> ease<00:07:07.259> of<00:07:07.440> fuse<00:07:07.800> so<00:07:08.220> the<00:07:08.759> invariant<00:07:09.240> are 00:07:09.409 --> 00:07:09.419 align:start position:0% know ease of fuse so the invariant are 00:07:09.419 --> 00:07:10.689 align:start position:0% know ease of fuse so the invariant are going<00:07:09.600> to<00:07:09.720> be 00:07:10.689 --> 00:07:10.699 align:start position:0% going to be 00:07:10.699 --> 00:07:13.430 align:start position:0% going to be describing<00:07:11.699> solidity<00:07:12.240> we<00:07:12.960> have<00:07:13.080> a<00:07:13.199> GitHub 00:07:13.430 --> 00:07:13.440 align:start position:0% describing solidity we have a GitHub 00:07:13.440 --> 00:07:15.170 align:start position:0% describing solidity we have a GitHub action<00:07:13.680> similar<00:07:14.100> to<00:07:14.280> slitter 00:07:15.170 --> 00:07:15.180 align:start position:0% action similar to slitter 00:07:15.180 --> 00:07:17.330 align:start position:0% action similar to slitter and<00:07:15.720> we<00:07:16.020> support<00:07:16.199> all<00:07:16.620> the<00:07:16.740> compilation<00:07:17.220> of 00:07:17.330 --> 00:07:17.340 align:start position:0% and we support all the compilation of 00:07:17.340 --> 00:07:19.490 align:start position:0% and we support all the compilation of framework<00:07:17.639> if<00:07:18.180> you<00:07:18.300> use<00:07:18.419> Foundry<00:07:18.900> are<00:07:19.199> that 00:07:19.490 --> 00:07:19.500 align:start position:0% framework if you use Foundry are that 00:07:19.500 --> 00:07:21.890 align:start position:0% framework if you use Foundry are that Bernie<00:07:20.039> travel<00:07:20.639> whatever<00:07:21.060> we're<00:07:21.539> going<00:07:21.780> to 00:07:21.890 --> 00:07:21.900 align:start position:0% Bernie travel whatever we're going to 00:07:21.900 --> 00:07:23.990 align:start position:0% Bernie travel whatever we're going to support<00:07:22.080> it<00:07:22.319> because<00:07:22.620> we<00:07:23.220> are<00:07:23.340> using<00:07:23.580> it<00:07:23.699> in 00:07:23.990 --> 00:07:24.000 align:start position:0% support it because we are using it in 00:07:24.000 --> 00:07:26.570 align:start position:0% support it because we are using it in every<00:07:24.300> of<00:07:24.539> our<00:07:24.660> audit<00:07:24.960> and<00:07:25.259> every<00:07:26.160> now<00:07:26.400> and 00:07:26.570 --> 00:07:26.580 align:start position:0% every of our audit and every now and 00:07:26.580 --> 00:07:27.650 align:start position:0% every of our audit and every now and then<00:07:26.699> someone<00:07:26.940> comes<00:07:27.300> with<00:07:27.360> a<00:07:27.539> new 00:07:27.650 --> 00:07:27.660 align:start position:0% then someone comes with a new 00:07:27.660 --> 00:07:31.550 align:start position:0% then someone comes with a new compilation<00:07:28.020> framework 00:07:31.550 --> 00:07:31.560 align:start position:0% 00:07:31.560 --> 00:07:33.290 align:start position:0% okay<00:07:31.860> I<00:07:32.099> was<00:07:32.160> talking<00:07:32.340> about<00:07:32.520> invariant<00:07:33.120> so 00:07:33.290 --> 00:07:33.300 align:start position:0% okay I was talking about invariant so 00:07:33.300 --> 00:07:35.029 align:start position:0% okay I was talking about invariant so let's<00:07:33.599> say<00:07:33.840> you<00:07:34.139> have<00:07:34.259> a<00:07:34.380> token<00:07:34.620> you<00:07:34.860> have<00:07:34.979> a 00:07:35.029 --> 00:07:35.039 align:start position:0% let's say you have a token you have a 00:07:35.039 --> 00:07:37.550 align:start position:0% let's say you have a token you have a Neo<00:07:35.280> C20<00:07:35.520> token<00:07:36.060> it<00:07:36.780> has<00:07:36.900> you<00:07:37.080> know<00:07:37.199> a<00:07:37.319> balance 00:07:37.550 --> 00:07:37.560 align:start position:0% Neo C20 token it has you know a balance 00:07:37.560 --> 00:07:40.010 align:start position:0% Neo C20 token it has you know a balance you<00:07:37.740> can<00:07:37.860> transfer<00:07:38.280> token<00:07:38.699> what<00:07:39.479> would<00:07:39.720> be<00:07:39.840> an 00:07:40.010 --> 00:07:40.020 align:start position:0% you can transfer token what would be an 00:07:40.020 --> 00:07:41.089 align:start position:0% you can transfer token what would be an invariance 00:07:41.089 --> 00:07:41.099 align:start position:0% invariance 00:07:41.099 --> 00:07:43.010 align:start position:0% invariance an<00:07:41.520> environment<00:07:41.940> could<00:07:42.180> be<00:07:42.360> that<00:07:42.599> if<00:07:42.840> you<00:07:42.900> have 00:07:43.010 --> 00:07:43.020 align:start position:0% an environment could be that if you have 00:07:43.020 --> 00:07:44.689 align:start position:0% an environment could be that if you have a<00:07:43.139> total<00:07:43.440> Supply 00:07:44.689 --> 00:07:44.699 align:start position:0% a total Supply 00:07:44.699 --> 00:07:47.390 align:start position:0% a total Supply no<00:07:45.599> user<00:07:46.080> in<00:07:46.259> the<00:07:46.440> system<00:07:46.560> should<00:07:47.039> have<00:07:47.220> not 00:07:47.390 --> 00:07:47.400 align:start position:0% no user in the system should have not 00:07:47.400 --> 00:07:49.430 align:start position:0% no user in the system should have not talking<00:07:47.580> to<00:07:47.940> the<00:07:48.060> total<00:07:48.360> Supply<00:07:48.539> right<00:07:48.960> if<00:07:49.319> you 00:07:49.430 --> 00:07:49.440 align:start position:0% talking to the total Supply right if you 00:07:49.440 --> 00:07:52.430 align:start position:0% talking to the total Supply right if you have<00:07:49.560> 10<00:07:49.800> million<00:07:50.220> of<00:07:50.460> token<00:07:50.940> if<00:07:51.539> a<00:07:51.780> user<00:07:52.080> of<00:07:52.199> 20 00:07:52.430 --> 00:07:52.440 align:start position:0% have 10 million of token if a user of 20 00:07:52.440 --> 00:07:57.830 align:start position:0% have 10 million of token if a user of 20 million<00:07:53.280> yeah<00:07:53.819> something<00:07:54.180> is<00:07:54.419> wrong 00:07:57.830 --> 00:07:57.840 align:start position:0% 00:07:57.840 --> 00:07:59.689 align:start position:0% the<00:07:58.380> way<00:07:58.440> it<00:07:58.620> works<00:07:58.919> is<00:07:59.099> that<00:07:59.220> you're<00:07:59.340> going<00:07:59.580> to 00:07:59.689 --> 00:07:59.699 align:start position:0% the way it works is that you're going to 00:07:59.699 --> 00:08:01.850 align:start position:0% the way it works is that you're going to take<00:07:59.940> the<00:08:00.120> contract<00:08:00.539> in<00:08:01.080> solidity<00:08:01.500> you're 00:08:01.850 --> 00:08:01.860 align:start position:0% take the contract in solidity you're 00:08:01.860 --> 00:08:03.830 align:start position:0% take the contract in solidity you're going<00:08:02.099> to<00:08:02.220> Define<00:08:02.400> invariants<00:08:03.120> which<00:08:03.720> are 00:08:03.830 --> 00:08:03.840 align:start position:0% going to Define invariants which are 00:08:03.840 --> 00:08:05.330 align:start position:0% going to Define invariants which are going<00:08:04.020> to<00:08:04.139> describe<00:08:04.620> what<00:08:04.800> you<00:08:04.919> are<00:08:05.039> trying<00:08:05.160> to 00:08:05.330 --> 00:08:05.340 align:start position:0% going to describe what you are trying to 00:08:05.340 --> 00:08:06.350 align:start position:0% going to describe what you are trying to check 00:08:06.350 --> 00:08:06.360 align:start position:0% check 00:08:06.360 --> 00:08:08.089 align:start position:0% check one<00:08:06.900> way<00:08:07.080> to<00:08:07.259> do<00:08:07.380> that<00:08:07.560> is<00:08:07.740> to<00:08:07.979> create 00:08:08.089 --> 00:08:08.099 align:start position:0% one way to do that is to create 00:08:08.099 --> 00:08:09.770 align:start position:0% one way to do that is to create functions<00:08:08.699> that<00:08:08.880> are<00:08:09.060> called<00:08:09.240> echina 00:08:09.770 --> 00:08:09.780 align:start position:0% functions that are called echina 00:08:09.780 --> 00:08:12.230 align:start position:0% functions that are called echina underscore<00:08:10.500> some<00:08:11.099> name<00:08:11.340> this<00:08:12.000> function 00:08:12.230 --> 00:08:12.240 align:start position:0% underscore some name this function 00:08:12.240 --> 00:08:14.510 align:start position:0% underscore some name this function should<00:08:12.479> work<00:08:12.660> on<00:08:12.900> a<00:08:13.020> Boolean<00:08:13.319> is<00:08:13.860> a<00:08:14.039> Boolean<00:08:14.340> is 00:08:14.510 --> 00:08:14.520 align:start position:0% should work on a Boolean is a Boolean is 00:08:14.520 --> 00:08:16.610 align:start position:0% should work on a Boolean is a Boolean is true<00:08:14.699> the<00:08:15.000> property<00:08:15.419> or<00:08:15.599> if<00:08:15.960> the<00:08:16.080> Boolean<00:08:16.440> is 00:08:16.610 --> 00:08:16.620 align:start position:0% true the property or if the Boolean is 00:08:16.620 --> 00:08:18.950 align:start position:0% true the property or if the Boolean is false<00:08:16.860> or<00:08:17.099> the<00:08:17.340> property<00:08:17.699> is<00:08:17.819> broken<00:08:18.000> you<00:08:18.780> give 00:08:18.950 --> 00:08:18.960 align:start position:0% false or the property is broken you give 00:08:18.960 --> 00:08:21.050 align:start position:0% false or the property is broken you give both<00:08:19.319> to<00:08:19.620> Akin<00:08:19.919> now<00:08:20.160> Akinator<00:08:20.699> is<00:08:20.879> going<00:08:20.940> to 00:08:21.050 --> 00:08:21.060 align:start position:0% both to Akin now Akinator is going to 00:08:21.060 --> 00:08:22.850 align:start position:0% both to Akin now Akinator is going to explore<00:08:21.360> one<00:08:21.539> Dominator<00:08:21.960> program<00:08:22.259> and<00:08:22.680> it's 00:08:22.850 --> 00:08:22.860 align:start position:0% explore one Dominator program and it's 00:08:22.860 --> 00:08:25.610 align:start position:0% explore one Dominator program and it's going<00:08:22.979> to<00:08:23.099> try<00:08:23.280> to<00:08:23.400> see<00:08:23.639> if<00:08:23.879> it<00:08:24.060> hurts 00:08:25.610 --> 00:08:25.620 align:start position:0% going to try to see if it hurts 00:08:25.620 --> 00:08:28.330 align:start position:0% going to try to see if it hurts foreign 00:08:28.330 --> 00:08:28.340 align:start position:0% 00:08:28.340 --> 00:08:29.990 align:start position:0% for<00:08:29.340> you 00:08:29.990 --> 00:08:30.000 align:start position:0% for you 00:08:30.000 --> 00:08:31.850 align:start position:0% for you so<00:08:30.660> we<00:08:30.960> have<00:08:31.139> we're<00:08:31.259> going<00:08:31.440> to<00:08:31.500> have<00:08:31.620> a<00:08:31.800> couple 00:08:31.850 --> 00:08:31.860 align:start position:0% so we have we're going to have a couple 00:08:31.860 --> 00:08:33.649 align:start position:0% so we have we're going to have a couple of<00:08:32.039> theory<00:08:32.339> of<00:08:32.459> exercise<00:08:32.700> where<00:08:33.300> you're<00:08:33.479> going 00:08:33.649 --> 00:08:33.659 align:start position:0% of theory of exercise where you're going 00:08:33.659 --> 00:08:35.630 align:start position:0% of theory of exercise where you're going to<00:08:33.719> try<00:08:33.899> to<00:08:34.080> apply<00:08:34.320> again<00:08:34.500> now<00:08:34.800> and<00:08:35.159> to<00:08:35.339> Define 00:08:35.630 --> 00:08:35.640 align:start position:0% to try to apply again now and to Define 00:08:35.640 --> 00:08:37.969 align:start position:0% to try to apply again now and to Define some<00:08:36.000> invariant<00:08:36.419> on<00:08:36.599> the<00:08:36.719> system<00:08:36.899> you<00:08:37.680> can<00:08:37.740> go 00:08:37.969 --> 00:08:37.979 align:start position:0% some invariant on the system you can go 00:08:37.979 --> 00:08:40.130 align:start position:0% some invariant on the system you can go on<00:08:38.279> this<00:08:38.399> repo<00:08:38.880> or<00:08:39.180> you<00:08:39.300> can<00:08:39.419> scan<00:08:39.599> the<00:08:39.779> QR<00:08:40.020> code 00:08:40.130 --> 00:08:40.140 align:start position:0% on this repo or you can scan the QR code 00:08:40.140 --> 00:08:41.690 align:start position:0% on this repo or you can scan the QR code to<00:08:40.320> object<00:08:40.500> repo 00:08:41.690 --> 00:08:41.700 align:start position:0% to object repo 00:08:41.700 --> 00:08:44.029 align:start position:0% to object repo check<00:08:42.120> out<00:08:42.300> the<00:08:42.839> Defcon<00:08:43.200> branch<00:08:43.500> and<00:08:43.680> open<00:08:43.800> the 00:08:44.029 --> 00:08:44.039 align:start position:0% check out the Defcon branch and open the 00:08:44.039 --> 00:08:46.070 align:start position:0% check out the Defcon branch and open the first<00:08:44.159> exercise 00:08:46.070 --> 00:08:46.080 align:start position:0% first exercise 00:08:46.080 --> 00:08:48.410 align:start position:0% first exercise if<00:08:46.560> you<00:08:46.680> have<00:08:46.860> any<00:08:47.160> problem<00:08:47.519> to<00:08:47.820> install<00:08:48.000> Akin 00:08:48.410 --> 00:08:48.420 align:start position:0% if you have any problem to install Akin 00:08:48.420 --> 00:08:56.930 align:start position:0% if you have any problem to install Akin now<00:08:48.600> if<00:08:48.839> you<00:08:48.899> have<00:08:48.959> any<00:08:49.140> question<00:08:49.380> let<00:08:50.220> us<00:08:50.339> know 00:08:56.930 --> 00:08:56.940 align:start position:0% 00:08:56.940 --> 00:09:00.530 align:start position:0% we<00:08:57.420> also<00:08:57.720> welcome<00:08:57.839> everyone<00:08:58.260> who<00:08:58.860> is<00:08:59.100> not<00:08:59.540> into 00:09:00.530 --> 00:09:00.540 align:start position:0% we also welcome everyone who is not into 00:09:00.540 --> 00:09:03.829 align:start position:0% we also welcome everyone who is not into the<00:09:00.839> exercises<00:09:01.320> just<00:09:01.740> to<00:09:01.980> see<00:09:02.240> even<00:09:03.240> even<00:09:03.540> if 00:09:03.829 --> 00:09:03.839 align:start position:0% the exercises just to see even even if 00:09:03.839 --> 00:09:07.009 align:start position:0% the exercises just to see even even if you're<00:09:04.019> already<00:09:04.580> uh<00:09:05.580> know<00:09:05.820> how<00:09:06.120> to<00:09:06.240> do<00:09:06.480> how<00:09:06.779> to 00:09:07.009 --> 00:09:07.019 align:start position:0% you're already uh know how to do how to 00:09:07.019 --> 00:09:09.590 align:start position:0% you're already uh know how to do how to do<00:09:07.140> testing<00:09:07.620> or<00:09:07.980> even<00:09:08.220> if<00:09:08.519> you<00:09:08.760> if<00:09:09.180> you<00:09:09.360> use 00:09:09.590 --> 00:09:09.600 align:start position:0% do testing or even if you if you use 00:09:09.600 --> 00:09:12.889 align:start position:0% do testing or even if you if you use fasting<00:09:10.140> every<00:09:10.380> day<00:09:10.640> uh<00:09:11.640> it's<00:09:11.940> it's<00:09:12.420> totally 00:09:12.889 --> 00:09:12.899 align:start position:0% fasting every day uh it's it's totally 00:09:12.899 --> 00:09:15.230 align:start position:0% fasting every day uh it's it's totally fine<00:09:13.140> we<00:09:13.440> will<00:09:13.560> happy<00:09:13.860> to<00:09:14.100> take<00:09:14.399> uh<00:09:15.000> any 00:09:15.230 --> 00:09:15.240 align:start position:0% fine we will happy to take uh any 00:09:15.240 --> 00:09:17.150 align:start position:0% fine we will happy to take uh any questions<00:09:15.480> simple<00:09:16.019> or<00:09:16.320> more<00:09:16.500> advanced<00:09:16.980> about 00:09:17.150 --> 00:09:17.160 align:start position:0% questions simple or more advanced about 00:09:17.160 --> 00:09:20.930 align:start position:0% questions simple or more advanced about how<00:09:18.000> Echidna<00:09:18.779> work<00:09:18.899> so<00:09:19.200> please<00:09:19.560> feel<00:09:19.800> free<00:09:19.980> to 00:09:20.930 --> 00:09:20.940 align:start position:0% how Echidna work so please feel free to 00:09:20.940 --> 00:09:22.850 align:start position:0% how Echidna work so please feel free to to<00:09:21.420> do<00:09:21.660> it 00:09:22.850 --> 00:09:22.860 align:start position:0% to do it 00:09:22.860 --> 00:09:26.750 align:start position:0% to do it and<00:09:23.820> we<00:09:24.060> will<00:09:24.240> take<00:09:24.600> 15<00:09:25.440> minutes<00:09:25.800> for<00:09:26.160> this<00:09:26.399> uh 00:09:26.750 --> 00:09:26.760 align:start position:0% and we will take 15 minutes for this uh 00:09:26.760 --> 00:09:45.110 align:start position:0% and we will take 15 minutes for this uh for<00:09:27.000> the<00:09:27.240> first<00:09:27.360> one 00:09:45.110 --> 00:09:45.120 align:start position:0% 00:09:45.120 --> 00:09:47.870 align:start position:0% okay<00:09:45.540> so<00:09:45.839> the<00:09:46.080> question<00:09:46.320> was<00:09:46.800> what<00:09:47.580> are<00:09:47.760> the 00:09:47.870 --> 00:09:47.880 align:start position:0% okay so the question was what are the 00:09:47.880 --> 00:09:51.410 align:start position:0% okay so the question was what are the benefits<00:09:48.240> of<00:09:48.360> using<00:09:48.720> Echidna<00:09:49.260> other<00:09:49.440> Foundry 00:09:51.410 --> 00:09:51.420 align:start position:0% benefits of using Echidna other Foundry 00:09:51.420 --> 00:09:53.990 align:start position:0% benefits of using Echidna other Foundry um<00:09:51.480> so<00:09:52.019> first<00:09:52.380> I<00:09:52.800> think<00:09:52.860> echina<00:09:53.399> has<00:09:53.700> more 00:09:53.990 --> 00:09:54.000 align:start position:0% um so first I think echina has more 00:09:54.000 --> 00:09:55.509 align:start position:0% um so first I think echina has more features<00:09:54.420> than<00:09:54.540> friendly<00:09:54.839> at<00:09:55.019> the<00:09:55.080> moment 00:09:55.509 --> 00:09:55.519 align:start position:0% features than friendly at the moment 00:09:55.519 --> 00:09:58.009 align:start position:0% features than friendly at the moment they<00:09:56.519> were<00:09:56.940> developing<00:09:57.360> Foundry<00:09:57.720> for<00:09:57.899> like 00:09:58.009 --> 00:09:58.019 align:start position:0% they were developing Foundry for like 00:09:58.019 --> 00:09:59.509 align:start position:0% they were developing Foundry for like six<00:09:58.200> months<00:09:58.380> we<00:09:58.560> have<00:09:58.680> been<00:09:58.800> using<00:09:59.040> a<00:09:59.160> canine 00:09:59.509 --> 00:09:59.519 align:start position:0% six months we have been using a canine 00:09:59.519 --> 00:10:01.210 align:start position:0% six months we have been using a canine like<00:09:59.880> four<00:10:00.300> years 00:10:01.210 --> 00:10:01.220 align:start position:0% like four years 00:10:01.220 --> 00:10:03.829 align:start position:0% like four years we<00:10:02.220> support<00:10:02.399> any<00:10:02.700> compilation<00:10:03.120> framework<00:10:03.600> so 00:10:03.829 --> 00:10:03.839 align:start position:0% we support any compilation framework so 00:10:03.839 --> 00:10:05.269 align:start position:0% we support any compilation framework so let's<00:10:04.019> say<00:10:04.200> you<00:10:04.320> are<00:10:04.440> using<00:10:04.620> r<00:10:04.800> dot<00:10:05.160> because 00:10:05.269 --> 00:10:05.279 align:start position:0% let's say you are using r dot because 00:10:05.279 --> 00:10:07.910 align:start position:0% let's say you are using r dot because you<00:10:05.519> want<00:10:05.640> to<00:10:05.760> do<00:10:06.000> integration<00:10:06.839> test<00:10:07.260> and<00:10:07.680> you 00:10:07.910 --> 00:10:07.920 align:start position:0% you want to do integration test and you 00:10:07.920 --> 00:10:10.490 align:start position:0% you want to do integration test and you need<00:10:08.100> some<00:10:08.399> complex<00:10:08.899> setup<00:10:09.899> using<00:10:10.320> like 00:10:10.490 --> 00:10:10.500 align:start position:0% need some complex setup using like 00:10:10.500 --> 00:10:12.050 align:start position:0% need some complex setup using like typescript<00:10:10.920> or<00:10:11.160> whatever 00:10:12.050 --> 00:10:12.060 align:start position:0% typescript or whatever 00:10:12.060 --> 00:10:14.150 align:start position:0% typescript or whatever if<00:10:12.839> you<00:10:12.959> move<00:10:13.140> to<00:10:13.320> Foundry<00:10:13.680> you're<00:10:13.860> going<00:10:14.040> to 00:10:14.150 --> 00:10:14.160 align:start position:0% if you move to Foundry you're going to 00:10:14.160 --> 00:10:16.190 align:start position:0% if you move to Foundry you're going to have<00:10:14.279> issue<00:10:14.700> because<00:10:14.940> it's<00:10:15.600> more<00:10:15.839> difficult 00:10:16.190 --> 00:10:16.200 align:start position:0% have issue because it's more difficult 00:10:16.200 --> 00:10:18.050 align:start position:0% have issue because it's more difficult to<00:10:16.560> you<00:10:16.680> know<00:10:16.800> create<00:10:16.980> this<00:10:17.220> type<00:10:17.339> of<00:10:17.459> test<00:10:17.640> so 00:10:18.050 --> 00:10:18.060 align:start position:0% to you know create this type of test so 00:10:18.060 --> 00:10:19.490 align:start position:0% to you know create this type of test so you<00:10:18.180> end<00:10:18.300> up<00:10:18.420> in<00:10:18.540> a<00:10:18.660> situation<00:10:18.899> where<00:10:19.140> you<00:10:19.380> need 00:10:19.490 --> 00:10:19.500 align:start position:0% you end up in a situation where you need 00:10:19.500 --> 00:10:20.630 align:start position:0% you end up in a situation where you need to<00:10:19.560> have<00:10:19.680> a<00:10:19.800> setup<00:10:20.040> with<00:10:20.279> two<00:10:20.459> different 00:10:20.630 --> 00:10:20.640 align:start position:0% to have a setup with two different 00:10:20.640 --> 00:10:22.790 align:start position:0% to have a setup with two different compilation<00:10:21.180> framework<00:10:21.660> if<00:10:22.320> you<00:10:22.440> use<00:10:22.560> some 00:10:22.790 --> 00:10:22.800 align:start position:0% compilation framework if you use some 00:10:22.800 --> 00:10:24.590 align:start position:0% compilation framework if you use some Advanced<00:10:23.160> options<00:10:23.399> then<00:10:23.580> you<00:10:23.820> have<00:10:23.880> to<00:10:24.000> need 00:10:24.590 --> 00:10:24.600 align:start position:0% Advanced options then you have to need 00:10:24.600 --> 00:10:26.269 align:start position:0% Advanced options then you have to need to<00:10:24.660> have<00:10:24.779> like<00:10:24.959> both<00:10:25.140> Advanced<00:10:25.680> option<00:10:25.920> in 00:10:26.269 --> 00:10:26.279 align:start position:0% to have like both Advanced option in 00:10:26.279 --> 00:10:28.009 align:start position:0% to have like both Advanced option in both<00:10:26.459> compilation<00:10:26.940> framework<00:10:27.360> if<00:10:27.839> they 00:10:28.009 --> 00:10:28.019 align:start position:0% both compilation framework if they 00:10:28.019 --> 00:10:29.810 align:start position:0% both compilation framework if they support<00:10:28.200> it<00:10:28.500> and<00:10:28.920> it's<00:10:29.100> a<00:10:29.339> lot<00:10:29.399> of<00:10:29.519> you<00:10:29.640> know 00:10:29.810 --> 00:10:29.820 align:start position:0% support it and it's a lot of you know 00:10:29.820 --> 00:10:31.310 align:start position:0% support it and it's a lot of you know like<00:10:29.880> maintenance 00:10:31.310 --> 00:10:31.320 align:start position:0% like maintenance 00:10:31.320 --> 00:10:32.810 align:start position:0% like maintenance um here<00:10:31.560> we<00:10:31.800> are<00:10:31.920> like<00:10:31.980> you<00:10:32.160> know<00:10:32.279> agnostic<00:10:32.700> to 00:10:32.810 --> 00:10:32.820 align:start position:0% um here we are like you know agnostic to 00:10:32.820 --> 00:10:34.310 align:start position:0% um here we are like you know agnostic to the<00:10:32.940> compilation<00:10:33.300> framework<00:10:33.720> in<00:10:33.899> that<00:10:34.080> sense 00:10:34.310 --> 00:10:34.320 align:start position:0% the compilation framework in that sense 00:10:34.320 --> 00:10:36.650 align:start position:0% the compilation framework in that sense we<00:10:35.279> have<00:10:35.459> we're<00:10:35.940> going<00:10:36.060> to<00:10:36.180> talk<00:10:36.300> about<00:10:36.420> that 00:10:36.650 --> 00:10:36.660 align:start position:0% we have we're going to talk about that 00:10:36.660 --> 00:10:38.030 align:start position:0% we have we're going to talk about that later<00:10:36.839> we<00:10:37.200> also<00:10:37.380> have<00:10:37.440> like<00:10:37.560> a<00:10:37.740> couple<00:10:37.860> of 00:10:38.030 --> 00:10:38.040 align:start position:0% later we also have like a couple of 00:10:38.040 --> 00:10:40.130 align:start position:0% later we also have like a couple of advanced<00:10:38.459> features<00:10:38.820> that<00:10:39.060> the<00:10:39.480> others<00:10:39.959> I 00:10:40.130 --> 00:10:40.140 align:start position:0% advanced features that the others I 00:10:40.140 --> 00:10:41.990 align:start position:0% advanced features that the others I don't<00:10:40.260> have<00:10:40.380> for<00:10:41.100> example<00:10:41.399> something<00:10:41.820> that 00:10:41.990 --> 00:10:42.000 align:start position:0% don't have for example something that 00:10:42.000 --> 00:10:44.150 align:start position:0% don't have for example something that you<00:10:42.120> can<00:10:42.240> do<00:10:42.360> with<00:10:42.480> echina<00:10:42.899> is<00:10:43.260> that<00:10:43.440> instead 00:10:44.150 --> 00:10:44.160 align:start position:0% you can do with echina is that instead 00:10:44.160 --> 00:10:45.350 align:start position:0% you can do with echina is that instead of<00:10:44.220> trying<00:10:44.399> to<00:10:44.579> find 00:10:45.350 --> 00:10:45.360 align:start position:0% of trying to find 00:10:45.360 --> 00:10:47.750 align:start position:0% of trying to find in<00:10:46.079> there<00:10:46.260> that<00:10:46.500> are<00:10:46.620> broken<00:10:46.800> you<00:10:47.399> can<00:10:47.519> look 00:10:47.750 --> 00:10:47.760 align:start position:0% in there that are broken you can look 00:10:47.760 --> 00:10:50.509 align:start position:0% in there that are broken you can look for<00:10:48.120> functions<00:10:49.079> that<00:10:49.260> consume<00:10:50.100> most<00:10:50.220> of<00:10:50.399> the 00:10:50.509 --> 00:10:50.519 align:start position:0% for functions that consume most of the 00:10:50.519 --> 00:10:53.269 align:start position:0% for functions that consume most of the gas<00:10:50.700> so<00:10:51.180> you<00:10:51.300> can<00:10:51.420> list<00:10:51.600> the<00:10:51.959> further<00:10:52.440> one<00:10:52.740> and 00:10:53.269 --> 00:10:53.279 align:start position:0% gas so you can list the further one and 00:10:53.279 --> 00:10:55.670 align:start position:0% gas so you can list the further one and give<00:10:53.459> you<00:10:53.640> a<00:10:53.760> summary<00:10:54.060> of<00:10:54.240> okay<00:10:54.420> I<00:10:55.140> can<00:10:55.320> learn 00:10:55.670 --> 00:10:55.680 align:start position:0% give you a summary of okay I can learn 00:10:55.680 --> 00:10:58.009 align:start position:0% give you a summary of okay I can learn this<00:10:55.980> function<00:10:56.279> with<00:10:57.060> this<00:10:57.240> parameter<00:10:57.839> and 00:10:58.009 --> 00:10:58.019 align:start position:0% this function with this parameter and 00:10:58.019 --> 00:10:59.630 align:start position:0% this function with this parameter and it's<00:10:58.140> going<00:10:58.320> to<00:10:58.440> Output<00:10:58.860> this<00:10:59.040> amount<00:10:59.279> of<00:10:59.459> gas 00:10:59.630 --> 00:10:59.640 align:start position:0% it's going to Output this amount of gas 00:10:59.640 --> 00:11:01.490 align:start position:0% it's going to Output this amount of gas and<00:11:00.120> if<00:11:00.300> you<00:11:00.420> are<00:11:00.540> looking<00:11:00.660> you<00:11:00.959> know<00:11:01.079> for<00:11:01.260> on 00:11:01.490 --> 00:11:01.500 align:start position:0% and if you are looking you know for on 00:11:01.500 --> 00:11:10.790 align:start position:0% and if you are looking you know for on this<00:11:01.740> type<00:11:01.860> of<00:11:01.980> things<00:11:02.160> uh<00:11:02.579> it's<00:11:02.820> very<00:11:03.180> nice 00:11:10.790 --> 00:11:10.800 align:start position:0% 00:11:10.800 --> 00:11:13.790 align:start position:0% hey<00:11:11.220> there<00:11:11.399> uh<00:11:12.060> Brock<00:11:12.420> from<00:11:12.600> Foundry<00:11:12.959> here 00:11:13.790 --> 00:11:13.800 align:start position:0% hey there uh Brock from Foundry here 00:11:13.800 --> 00:11:16.009 align:start position:0% hey there uh Brock from Foundry here um<00:11:13.860> I'm<00:11:14.040> curious<00:11:14.459> uh<00:11:14.940> how 00:11:16.009 --> 00:11:16.019 align:start position:0% um I'm curious uh how 00:11:16.019 --> 00:11:20.449 align:start position:0% um I'm curious uh how do<00:11:16.560> you<00:11:16.740> go<00:11:16.860> about<00:11:17.040> benchmarking<00:11:18.140> uh<00:11:19.140> a<00:11:19.800> fuzzer 00:11:20.449 --> 00:11:20.459 align:start position:0% do you go about benchmarking uh a fuzzer 00:11:20.459 --> 00:11:22.490 align:start position:0% do you go about benchmarking uh a fuzzer right<00:11:20.760> so<00:11:21.000> how<00:11:21.240> do<00:11:21.420> you 00:11:22.490 --> 00:11:22.500 align:start position:0% right so how do you 00:11:22.500 --> 00:11:24.050 align:start position:0% right so how do you um<00:11:22.560> because<00:11:22.860> it's<00:11:23.040> something<00:11:23.220> like<00:11:23.519> for<00:11:23.880> us 00:11:24.050 --> 00:11:24.060 align:start position:0% um because it's something like for us 00:11:24.060 --> 00:11:26.810 align:start position:0% um because it's something like for us it's<00:11:24.180> just<00:11:24.360> a<00:11:24.480> black<00:11:24.660> box<00:11:24.839> yeah<00:11:25.320> and<00:11:25.800> yeah<00:11:26.519> okay 00:11:26.810 --> 00:11:26.820 align:start position:0% it's just a black box yeah and yeah okay 00:11:26.820 --> 00:11:29.150 align:start position:0% it's just a black box yeah and yeah okay that's<00:11:27.120> a<00:11:27.360> really<00:11:27.600> good<00:11:27.779> question<00:11:28.019> and<00:11:28.800> even 00:11:29.150 --> 00:11:29.160 align:start position:0% that's a really good question and even 00:11:29.160 --> 00:11:31.069 align:start position:0% that's a really good question and even in<00:11:29.399> like<00:11:29.579> traditional<00:11:30.120> Feathering<00:11:30.660> you<00:11:30.959> know 00:11:31.069 --> 00:11:31.079 align:start position:0% in like traditional Feathering you know 00:11:31.079 --> 00:11:32.990 align:start position:0% in like traditional Feathering you know like<00:11:31.200> if<00:11:31.380> you<00:11:31.500> go<00:11:31.680> like<00:11:31.860> in<00:11:32.100> the<00:11:32.220> literature<00:11:32.700> of 00:11:32.990 --> 00:11:33.000 align:start position:0% like if you go like in the literature of 00:11:33.000 --> 00:11:35.090 align:start position:0% like if you go like in the literature of whole<00:11:33.300> feather<00:11:33.540> or<00:11:33.839> benchmark 00:11:35.090 --> 00:11:35.100 align:start position:0% whole feather or benchmark 00:11:35.100 --> 00:11:37.190 align:start position:0% whole feather or benchmark I<00:11:35.459> would<00:11:35.760> say<00:11:35.940> that<00:11:36.120> most<00:11:36.300> of<00:11:36.480> the<00:11:36.600> benchmarks 00:11:37.190 --> 00:11:37.200 align:start position:0% I would say that most of the benchmarks 00:11:37.200 --> 00:11:39.769 align:start position:0% I would say that most of the benchmarks are<00:11:37.380> poor<00:11:37.860> or<00:11:38.040> one<00:11:39.000> of<00:11:39.060> the<00:11:39.120> issues<00:11:39.360> that<00:11:39.540> when 00:11:39.769 --> 00:11:39.779 align:start position:0% are poor or one of the issues that when 00:11:39.779 --> 00:11:41.269 align:start position:0% are poor or one of the issues that when someone<00:11:40.019> does<00:11:40.320> a<00:11:40.440> benchmark<00:11:40.800> to<00:11:41.040> you<00:11:41.160> know 00:11:41.269 --> 00:11:41.279 align:start position:0% someone does a benchmark to you know 00:11:41.279 --> 00:11:42.949 align:start position:0% someone does a benchmark to you know benchmark<00:11:41.640> their<00:11:41.880> own<00:11:42.060> tool 00:11:42.949 --> 00:11:42.959 align:start position:0% benchmark their own tool 00:11:42.959 --> 00:11:46.009 align:start position:0% benchmark their own tool there's<00:11:43.380> a<00:11:43.620> bias<00:11:43.980> all<00:11:44.700> right<00:11:44.760> so<00:11:45.300> we<00:11:45.480> we<00:11:45.720> have 00:11:46.009 --> 00:11:46.019 align:start position:0% there's a bias all right so we we have 00:11:46.019 --> 00:11:47.690 align:start position:0% there's a bias all right so we we have Benchmark<00:11:46.440> we<00:11:46.680> have<00:11:46.860> our<00:11:46.980> own<00:11:47.100> Benchmark<00:11:47.459> to 00:11:47.690 --> 00:11:47.700 align:start position:0% Benchmark we have our own Benchmark to 00:11:47.700 --> 00:11:48.889 align:start position:0% Benchmark we have our own Benchmark to try<00:11:47.880> to<00:11:48.000> see<00:11:48.120> you<00:11:48.240> know<00:11:48.360> like<00:11:48.480> in<00:11:48.600> our<00:11:48.720> past 00:11:48.889 --> 00:11:48.899 align:start position:0% try to see you know like in our past 00:11:48.899 --> 00:11:50.329 align:start position:0% try to see you know like in our past audit<00:11:49.260> and<00:11:49.440> everything<00:11:49.500> how<00:11:49.860> it<00:11:50.040> works<00:11:50.279> and 00:11:50.329 --> 00:11:50.339 align:start position:0% audit and everything how it works and 00:11:50.339 --> 00:11:52.190 align:start position:0% audit and everything how it works and everything<00:11:50.519> but<00:11:51.120> obviously<00:11:51.480> we<00:11:51.660> have<00:11:51.779> a<00:11:51.899> bias 00:11:52.190 --> 00:11:52.200 align:start position:0% everything but obviously we have a bias 00:11:52.200 --> 00:11:54.530 align:start position:0% everything but obviously we have a bias like<00:11:52.860> it<00:11:53.040> works<00:11:53.339> well<00:11:53.399> for<00:11:53.700> us<00:11:53.820> because<00:11:54.180> we<00:11:54.420> are 00:11:54.530 --> 00:11:54.540 align:start position:0% like it works well for us because we are 00:11:54.540 --> 00:11:55.790 align:start position:0% like it works well for us because we are you<00:11:54.660> know<00:11:54.779> building<00:11:54.959> the<00:11:55.140> tool<00:11:55.440> on<00:11:55.620> our 00:11:55.790 --> 00:11:55.800 align:start position:0% you know building the tool on our 00:11:55.800 --> 00:11:57.350 align:start position:0% you know building the tool on our example 00:11:57.350 --> 00:11:57.360 align:start position:0% example 00:11:57.360 --> 00:11:59.569 align:start position:0% example um<00:11:57.480> so<00:11:57.720> I<00:11:57.899> would<00:11:58.079> say<00:11:58.320> like<00:11:58.500> the<00:11:58.800> best<00:11:58.980> place<00:11:59.339> to 00:11:59.569 --> 00:11:59.579 align:start position:0% um so I would say like the best place to 00:11:59.579 --> 00:12:01.670 align:start position:0% um so I would say like the best place to have<00:11:59.820> like<00:12:00.060> a<00:12:00.300> good<00:12:00.600> Benchmark<00:12:01.019> for<00:12:01.200> fuzzing 00:12:01.670 --> 00:12:01.680 align:start position:0% have like a good Benchmark for fuzzing 00:12:01.680 --> 00:12:05.290 align:start position:0% have like a good Benchmark for fuzzing should<00:12:02.220> not<00:12:02.459> come<00:12:03.120> from<00:12:03.420> to<00:12:03.899> level 00:12:05.290 --> 00:12:05.300 align:start position:0% should not come from to level 00:12:05.300 --> 00:12:07.610 align:start position:0% should not come from to level yeah<00:12:06.300> yeah<00:12:06.300> it's<00:12:06.660> it's<00:12:06.959> also<00:12:07.320> an<00:12:07.440> open 00:12:07.610 --> 00:12:07.620 align:start position:0% yeah yeah it's it's also an open 00:12:07.620 --> 00:12:10.130 align:start position:0% yeah yeah it's it's also an open question<00:12:07.980> what<00:12:08.760> is<00:12:09.000> your<00:12:09.120> benchmarking<00:12:09.899> like 00:12:10.130 --> 00:12:10.140 align:start position:0% question what is your benchmarking like 00:12:10.140 --> 00:12:12.230 align:start position:0% question what is your benchmarking like if<00:12:10.740> you<00:12:10.860> if<00:12:11.160> you<00:12:11.279> are<00:12:11.399> if<00:12:11.640> you're<00:12:11.760> saying<00:12:12.120> well 00:12:12.230 --> 00:12:12.240 align:start position:0% if you if you are if you're saying well 00:12:12.240 --> 00:12:14.090 align:start position:0% if you if you are if you're saying well this<00:12:12.600> is<00:12:12.720> faster<00:12:13.079> than<00:12:13.440> this<00:12:13.680> sort<00:12:13.860> of<00:12:13.980> thing 00:12:14.090 --> 00:12:14.100 align:start position:0% this is faster than this sort of thing 00:12:14.100 --> 00:12:16.790 align:start position:0% this is faster than this sort of thing but<00:12:14.880> it<00:12:15.240> could<00:12:15.420> be<00:12:15.540> executing<00:12:16.200> just<00:12:16.500> always 00:12:16.790 --> 00:12:16.800 align:start position:0% but it could be executing just always 00:12:16.800 --> 00:12:18.590 align:start position:0% but it could be executing just always the<00:12:17.100> same<00:12:17.279> thing<00:12:17.399> like<00:12:17.640> you<00:12:17.880> know<00:12:17.940> calling<00:12:18.480> a 00:12:18.590 --> 00:12:18.600 align:start position:0% the same thing like you know calling a 00:12:18.600 --> 00:12:20.030 align:start position:0% the same thing like you know calling a constant<00:12:18.899> function<00:12:19.140> over<00:12:19.320> and<00:12:19.500> over<00:12:19.620> again<00:12:19.800> is 00:12:20.030 --> 00:12:20.040 align:start position:0% constant function over and over again is 00:12:20.040 --> 00:12:22.130 align:start position:0% constant function over and over again is going<00:12:20.220> to<00:12:20.279> be<00:12:20.399> faster<00:12:20.700> than<00:12:21.000> calling<00:12:21.839> some 00:12:22.130 --> 00:12:22.140 align:start position:0% going to be faster than calling some 00:12:22.140 --> 00:12:25.069 align:start position:0% going to be faster than calling some deep<00:12:22.440> deep<00:12:22.680> part<00:12:22.980> in<00:12:23.220> the<00:12:23.339> in<00:12:23.579> the<00:12:23.700> call<00:12:23.880> uh<00:12:24.839> on 00:12:25.069 --> 00:12:25.079 align:start position:0% deep deep part in the in the call uh on 00:12:25.079 --> 00:12:27.350 align:start position:0% deep deep part in the in the call uh on top<00:12:25.200> of<00:12:25.320> that<00:12:25.440> you<00:12:25.680> have<00:12:25.860> like<00:12:26.100> bugs<00:12:26.700> what 00:12:27.350 --> 00:12:27.360 align:start position:0% top of that you have like bugs what 00:12:27.360 --> 00:12:29.690 align:start position:0% top of that you have like bugs what about<00:12:27.480> like<00:12:27.720> finding<00:12:28.200> bars<00:12:28.620> how<00:12:29.100> much<00:12:29.220> bugs 00:12:29.690 --> 00:12:29.700 align:start position:0% about like finding bars how much bugs 00:12:29.700 --> 00:12:32.329 align:start position:0% about like finding bars how much bugs you<00:12:29.940> found<00:12:30.180> and<00:12:31.019> there<00:12:31.680> is<00:12:31.860> there<00:12:32.160> are<00:12:32.279> a 00:12:32.329 --> 00:12:32.339 align:start position:0% you found and there is there are a 00:12:32.339 --> 00:12:34.190 align:start position:0% you found and there is there are a couple<00:12:32.399> of<00:12:32.519> academic<00:12:33.060> papers<00:12:33.420> saying<00:12:33.899> that 00:12:34.190 --> 00:12:34.200 align:start position:0% couple of academic papers saying that 00:12:34.200 --> 00:12:38.210 align:start position:0% couple of academic papers saying that some<00:12:35.100> people<00:12:35.399> uh<00:12:36.240> like<00:12:36.540> to<00:12:36.720> compare<00:12:37.260> this<00:12:37.560> but 00:12:38.210 --> 00:12:38.220 align:start position:0% some people uh like to compare this but 00:12:38.220 --> 00:12:40.790 align:start position:0% some people uh like to compare this but you<00:12:38.519> have<00:12:38.700> a<00:12:38.880> like<00:12:39.600> um<00:12:39.600> like<00:12:40.019> a<00:12:40.200> plot<00:12:40.440> saying 00:12:40.790 --> 00:12:40.800 align:start position:0% you have a like um like a plot saying 00:12:40.800 --> 00:12:42.829 align:start position:0% you have a like um like a plot saying how<00:12:40.980> many<00:12:41.100> Bucks<00:12:41.339> you<00:12:41.700> found<00:12:42.000> and<00:12:42.480> let's<00:12:42.660> say 00:12:42.829 --> 00:12:42.839 align:start position:0% how many Bucks you found and let's say 00:12:42.839 --> 00:12:44.569 align:start position:0% how many Bucks you found and let's say that<00:12:43.079> one<00:12:43.500> faster<00:12:43.740> is<00:12:43.980> better<00:12:44.160> than<00:12:44.339> the<00:12:44.459> other 00:12:44.569 --> 00:12:44.579 align:start position:0% that one faster is better than the other 00:12:44.579 --> 00:12:47.569 align:start position:0% that one faster is better than the other but<00:12:45.240> you<00:12:45.360> don't<00:12:45.480> know<00:12:45.660> if<00:12:45.959> the<00:12:46.139> next<00:12:46.680> hour<00:12:46.980> you 00:12:47.569 --> 00:12:47.579 align:start position:0% but you don't know if the next hour you 00:12:47.579 --> 00:12:50.690 align:start position:0% but you don't know if the next hour you will<00:12:47.760> have<00:12:48.060> a<00:12:48.300> a<00:12:48.920> peak<00:12:49.920> saying<00:12:50.220> well<00:12:50.339> these 00:12:50.690 --> 00:12:50.700 align:start position:0% will have a a peak saying well these 00:12:50.700 --> 00:12:53.150 align:start position:0% will have a a peak saying well these found<00:12:50.880> a<00:12:51.120> lot<00:12:51.240> of<00:12:51.360> things<00:12:51.600> so<00:12:52.560> there<00:12:52.920> are<00:12:53.040> all 00:12:53.150 --> 00:12:53.160 align:start position:0% found a lot of things so there are all 00:12:53.160 --> 00:12:54.470 align:start position:0% found a lot of things so there are all the<00:12:53.339> things<00:12:53.459> that<00:12:53.700> you<00:12:53.820> can<00:12:53.940> do<00:12:54.060> so<00:12:54.240> you<00:12:54.360> can 00:12:54.470 --> 00:12:54.480 align:start position:0% the things that you can do so you can 00:12:54.480 --> 00:12:56.629 align:start position:0% the things that you can do so you can use<00:12:54.660> coverage<00:12:55.200> but<00:12:55.620> also<00:12:55.860> coverage<00:12:56.160> is<00:12:56.399> not 00:12:56.629 --> 00:12:56.639 align:start position:0% use coverage but also coverage is not 00:12:56.639 --> 00:13:00.410 align:start position:0% use coverage but also coverage is not going<00:12:56.880> to<00:12:57.000> give<00:12:57.300> you<00:12:57.480> like<00:12:58.380> uh<00:12:58.920> uh<00:12:59.339> it's<00:13:00.300> not 00:13:00.410 --> 00:13:00.420 align:start position:0% going to give you like uh uh it's not 00:13:00.420 --> 00:13:02.509 align:start position:0% going to give you like uh uh it's not going<00:13:00.600> to<00:13:00.720> be<00:13:00.899> the<00:13:01.200> the<00:13:01.380> ultimate<00:13:01.860> answer<00:13:02.100> so 00:13:02.509 --> 00:13:02.519 align:start position:0% going to be the the ultimate answer so 00:13:02.519 --> 00:13:05.810 align:start position:0% going to be the the ultimate answer so it's<00:13:03.240> it's<00:13:03.420> still<00:13:03.779> a<00:13:04.139> debate<00:13:04.620> how<00:13:04.980> long<00:13:05.160> you 00:13:05.810 --> 00:13:05.820 align:start position:0% it's it's still a debate how long you 00:13:05.820 --> 00:13:08.449 align:start position:0% it's it's still a debate how long you should<00:13:06.120> run<00:13:06.420> faster<00:13:07.139> for<00:13:07.380> a<00:13:07.500> benchmark<00:13:07.860> or 00:13:08.449 --> 00:13:08.459 align:start position:0% should run faster for a benchmark or 00:13:08.459 --> 00:13:11.410 align:start position:0% should run faster for a benchmark or even<00:13:08.579> for<00:13:09.540> you<00:13:09.899> know<00:13:10.019> testing<00:13:10.620> something 00:13:11.410 --> 00:13:11.420 align:start position:0% even for you know testing something 00:13:11.420 --> 00:13:14.150 align:start position:0% even for you know testing something it's<00:13:12.420> also<00:13:12.660> a<00:13:12.779> debate<00:13:13.079> what<00:13:13.560> you<00:13:13.680> what<00:13:13.980> we 00:13:14.150 --> 00:13:14.160 align:start position:0% it's also a debate what you what we 00:13:14.160 --> 00:13:17.750 align:start position:0% it's also a debate what you what we should<00:13:14.339> use<00:13:14.579> for<00:13:15.260> benchmarking<00:13:16.279> uh<00:13:17.279> should<00:13:17.579> we 00:13:17.750 --> 00:13:17.760 align:start position:0% should use for benchmarking uh should we 00:13:17.760 --> 00:13:21.470 align:start position:0% should use for benchmarking uh should we use<00:13:17.940> like<00:13:18.360> complex<00:13:19.200> defy<00:13:20.160> applications<00:13:20.820> like 00:13:21.470 --> 00:13:21.480 align:start position:0% use like complex defy applications like 00:13:21.480 --> 00:13:23.990 align:start position:0% use like complex defy applications like but<00:13:21.839> how<00:13:22.139> many<00:13:22.320> of<00:13:22.500> them<00:13:22.620> we<00:13:22.860> have<00:13:23.100> like<00:13:23.399> 10<00:13:23.700> or 00:13:23.990 --> 00:13:24.000 align:start position:0% but how many of them we have like 10 or 00:13:24.000 --> 00:13:26.990 align:start position:0% but how many of them we have like 10 or 20<00:13:24.300> we<00:13:25.019> don't<00:13:25.200> have<00:13:25.579> thousands<00:13:26.579> of<00:13:26.760> different 00:13:26.990 --> 00:13:27.000 align:start position:0% 20 we don't have thousands of different 00:13:27.000 --> 00:13:30.230 align:start position:0% 20 we don't have thousands of different device<00:13:27.360> so<00:13:27.720> it's<00:13:27.899> it's<00:13:28.139> uh<00:13:29.040> we<00:13:29.220> we<00:13:29.459> definitely 00:13:30.230 --> 00:13:30.240 align:start position:0% device so it's it's uh we we definitely 00:13:30.240 --> 00:13:33.170 align:start position:0% device so it's it's uh we we definitely are<00:13:30.480> interested<00:13:30.839> in<00:13:30.899> a<00:13:31.260> deeper<00:13:31.920> discussion<00:13:32.339> on 00:13:33.170 --> 00:13:33.180 align:start position:0% are interested in a deeper discussion on 00:13:33.180 --> 00:13:35.690 align:start position:0% are interested in a deeper discussion on how<00:13:33.720> to<00:13:33.899> have<00:13:34.079> a<00:13:34.260> good<00:13:34.380> band<00:13:34.560> merch<00:13:35.040> set<00:13:35.279> for 00:13:35.690 --> 00:13:35.700 align:start position:0% how to have a good band merch set for 00:13:35.700 --> 00:13:37.370 align:start position:0% how to have a good band merch set for for<00:13:35.940> touring<00:13:36.420> and<00:13:36.660> we<00:13:36.779> have<00:13:37.079> the<00:13:37.139> same<00:13:37.260> problem 00:13:37.370 --> 00:13:37.380 align:start position:0% for touring and we have the same problem 00:13:37.380 --> 00:13:39.590 align:start position:0% for touring and we have the same problem for<00:13:37.620> example<00:13:37.800> with<00:13:37.980> Rita<00:13:38.339> well<00:13:38.940> how<00:13:39.420> do<00:13:39.540> we 00:13:39.590 --> 00:13:39.600 align:start position:0% for example with Rita well how do we 00:13:39.600 --> 00:13:41.690 align:start position:0% for example with Rita well how do we Benchmark<00:13:39.959> it<00:13:40.200> our<00:13:40.560> static<00:13:40.920> analyzer<00:13:41.279> provide 00:13:41.690 --> 00:13:41.700 align:start position:0% Benchmark it our static analyzer provide 00:13:41.700 --> 00:13:44.269 align:start position:0% Benchmark it our static analyzer provide good<00:13:41.880> weather<00:13:42.260> and<00:13:43.260> it's<00:13:43.440> tough 00:13:44.269 --> 00:13:44.279 align:start position:0% good weather and it's tough 00:13:44.279 --> 00:13:46.730 align:start position:0% good weather and it's tough um<00:13:44.339> we<00:13:45.060> usually<00:13:45.360> tend<00:13:45.839> to<00:13:45.959> have<00:13:46.200> a<00:13:46.380> practical 00:13:46.730 --> 00:13:46.740 align:start position:0% um we usually tend to have a practical 00:13:46.740 --> 00:13:49.250 align:start position:0% um we usually tend to have a practical approach<00:13:47.160> in<00:13:47.760> the<00:13:47.880> sense<00:13:48.060> that<00:13:48.240> if<00:13:48.779> the<00:13:48.959> truth 00:13:49.250 --> 00:13:49.260 align:start position:0% approach in the sense that if the truth 00:13:49.260 --> 00:13:51.410 align:start position:0% approach in the sense that if the truth provide<00:13:49.620> value<00:13:49.800> during<00:13:50.100> our<00:13:50.339> audit<00:13:50.760> if<00:13:51.120> it 00:13:51.410 --> 00:13:51.420 align:start position:0% provide value during our audit if it 00:13:51.420 --> 00:13:53.690 align:start position:0% provide value during our audit if it helps<00:13:51.779> us<00:13:51.899> you<00:13:52.200> know<00:13:52.320> to<00:13:52.680> find<00:13:52.860> bugs<00:13:53.279> and<00:13:53.519> we 00:13:53.690 --> 00:13:53.700 align:start position:0% helps us you know to find bugs and we 00:13:53.700 --> 00:13:55.730 align:start position:0% helps us you know to find bugs and we make<00:13:53.880> us<00:13:54.120> faster 00:13:55.730 --> 00:13:55.740 align:start position:0% make us faster 00:13:55.740 --> 00:13:58.069 align:start position:0% make us faster that's<00:13:56.339> good<00:13:56.639> enough<00:13:56.760> for<00:13:57.000> us 00:13:58.069 --> 00:13:58.079 align:start position:0% that's good enough for us 00:13:58.079 --> 00:14:00.170 align:start position:0% that's good enough for us yeah<00:13:58.620> and<00:13:58.800> at<00:13:59.279> the<00:13:59.399> end<00:13:59.519> of<00:13:59.639> the<00:13:59.700> day<00:13:59.820> also 00:14:00.170 --> 00:14:00.180 align:start position:0% yeah and at the end of the day also 00:14:00.180 --> 00:14:02.389 align:start position:0% yeah and at the end of the day also depends<00:14:00.540> on<00:14:00.660> the<00:14:00.779> invariance<00:14:01.260> if<00:14:01.740> the<00:14:01.920> if<00:14:02.160> the 00:14:02.389 --> 00:14:02.399 align:start position:0% depends on the invariance if the if the 00:14:02.399 --> 00:14:04.310 align:start position:0% depends on the invariance if the if the if<00:14:02.700> the<00:14:02.820> developers<00:14:03.240> don't<00:14:03.540> know<00:14:03.779> how<00:14:04.260> to 00:14:04.310 --> 00:14:04.320 align:start position:0% if the developers don't know how to 00:14:04.320 --> 00:14:06.410 align:start position:0% if the developers don't know how to write<00:14:04.440> good<00:14:04.680> invariants<00:14:05.160> then<00:14:05.700> no<00:14:05.940> tool<00:14:06.360> is 00:14:06.410 --> 00:14:06.420 align:start position:0% write good invariants then no tool is 00:14:06.420 --> 00:14:09.050 align:start position:0% write good invariants then no tool is going<00:14:06.660> to<00:14:06.839> provide<00:14:07.440> some<00:14:07.800> magic 00:14:09.050 --> 00:14:09.060 align:start position:0% going to provide some magic 00:14:09.060 --> 00:14:13.910 align:start position:0% going to provide some magic um<00:14:09.120> value<00:14:09.420> so<00:14:09.720> it's<00:14:09.899> it's<00:14:10.200> it's<00:14:10.320> tough 00:14:13.910 --> 00:14:13.920 align:start position:0% 00:14:13.920 --> 00:14:16.370 align:start position:0% okay<00:14:14.339> okay<00:14:14.399> and<00:14:14.940> I'm<00:14:15.120> happy<00:14:15.420> to<00:14:15.660> discuss<00:14:16.079> with 00:14:16.370 --> 00:14:16.380 align:start position:0% okay okay and I'm happy to discuss with 00:14:16.380 --> 00:14:18.350 align:start position:0% okay okay and I'm happy to discuss with with<00:14:16.500> The<00:14:17.040> Foundry<00:14:17.399> team<00:14:17.579> or<00:14:17.700> any<00:14:17.880> other<00:14:18.060> team 00:14:18.350 --> 00:14:18.360 align:start position:0% with The Foundry team or any other team 00:14:18.360 --> 00:14:20.690 align:start position:0% with The Foundry team or any other team doing<00:14:18.660> doing<00:14:18.720> fasting<00:14:19.500> we<00:14:19.680> will<00:14:19.860> will<00:14:20.220> be<00:14:20.459> here 00:14:20.690 --> 00:14:20.700 align:start position:0% doing doing fasting we will will be here 00:14:20.700 --> 00:14:24.530 align:start position:0% doing doing fasting we will will be here uh<00:14:21.180> today<00:14:21.360> so<00:14:21.839> please<00:14:22.320> let<00:14:22.620> us<00:14:22.740> know<00:14:23.060> okay<00:14:24.060> my 00:14:24.530 --> 00:14:24.540 align:start position:0% uh today so please let us know okay my 00:14:24.540 --> 00:14:27.470 align:start position:0% uh today so please let us know okay my other<00:14:25.139> question<00:14:25.500> is<00:14:25.800> regarding<00:14:26.339> like<00:14:26.880> the 00:14:27.470 --> 00:14:27.480 align:start position:0% other question is regarding like the 00:14:27.480 --> 00:14:29.509 align:start position:0% other question is regarding like the tool<00:14:27.839> is<00:14:27.959> only<00:14:28.079> for<00:14:28.320> passing<00:14:28.800> for<00:14:29.100> its<00:14:29.399> support 00:14:29.509 --> 00:14:29.519 align:start position:0% tool is only for passing for its support 00:14:29.519 --> 00:14:31.550 align:start position:0% tool is only for passing for its support like<00:14:29.880> symbolic<00:14:30.480> execution<00:14:31.019> or<00:14:31.380> something 00:14:31.550 --> 00:14:31.560 align:start position:0% like symbolic execution or something 00:14:31.560 --> 00:14:35.329 align:start position:0% like symbolic execution or something like<00:14:31.800> that<00:14:32.519> so<00:14:33.240> yeah<00:14:33.540> you<00:14:34.019> want<00:14:34.200> to<00:14:34.380> yeah<00:14:35.160> it's 00:14:35.329 --> 00:14:35.339 align:start position:0% like that so yeah you want to yeah it's 00:14:35.339 --> 00:14:36.650 align:start position:0% like that so yeah you want to yeah it's it's<00:14:35.399> only<00:14:35.700> for<00:14:35.880> first<00:14:36.120> thing<00:14:36.300> we<00:14:36.480> have 00:14:36.650 --> 00:14:36.660 align:start position:0% it's only for first thing we have 00:14:36.660 --> 00:14:38.389 align:start position:0% it's only for first thing we have another<00:14:36.839> tool<00:14:37.320> for<00:14:37.440> symbolic<00:14:38.040> execution 00:14:38.389 --> 00:14:38.399 align:start position:0% another tool for symbolic execution 00:14:38.399 --> 00:14:40.370 align:start position:0% another tool for symbolic execution which<00:14:38.700> is<00:14:38.760> called<00:14:38.940> Mantika 00:14:40.370 --> 00:14:40.380 align:start position:0% which is called Mantika 00:14:40.380 --> 00:14:42.410 align:start position:0% which is called Mantika however<00:14:41.040> and<00:14:41.519> something<00:14:41.820> actually<00:14:42.060> we're 00:14:42.410 --> 00:14:42.420 align:start position:0% however and something actually we're 00:14:42.420 --> 00:14:44.150 align:start position:0% however and something actually we're going<00:14:42.660> to<00:14:42.779> discuss<00:14:42.959> later 00:14:44.150 --> 00:14:44.160 align:start position:0% going to discuss later 00:14:44.160 --> 00:14:48.110 align:start position:0% going to discuss later I<00:14:44.699> think<00:14:45.079> in<00:14:46.079> practice<00:14:46.339> any<00:14:47.339> formal<00:14:47.880> base 00:14:48.110 --> 00:14:48.120 align:start position:0% I think in practice any formal base 00:14:48.120 --> 00:14:51.170 align:start position:0% I think in practice any formal base method<00:14:48.720> approach<00:14:49.320> is<00:14:49.980> going<00:14:50.160> to<00:14:50.339> have<00:14:50.639> a<00:14:51.060> lower 00:14:51.170 --> 00:14:51.180 align:start position:0% method approach is going to have a lower 00:14:51.180 --> 00:14:54.410 align:start position:0% method approach is going to have a lower return<00:14:51.540> on<00:14:51.899> investment<00:14:52.440> at<00:14:52.740> further<00:14:53.240> if<00:14:54.240> you 00:14:54.410 --> 00:14:54.420 align:start position:0% return on investment at further if you 00:14:54.420 --> 00:14:55.970 align:start position:0% return on investment at further if you have<00:14:54.540> two<00:14:54.779> weeks<00:14:55.079> three<00:14:55.199> weeks<00:14:55.500> to<00:14:55.620> work<00:14:55.740> on<00:14:55.860> a 00:14:55.970 --> 00:14:55.980 align:start position:0% have two weeks three weeks to work on a 00:14:55.980 --> 00:14:57.769 align:start position:0% have two weeks three weeks to work on a project<00:14:56.160> you<00:14:56.639> know<00:14:56.760> and<00:14:57.060> you<00:14:57.240> want<00:14:57.360> to<00:14:57.480> invest 00:14:57.769 --> 00:14:57.779 align:start position:0% project you know and you want to invest 00:14:57.779 --> 00:14:59.689 align:start position:0% project you know and you want to invest some<00:14:58.019> resource<00:14:58.680> to<00:14:58.920> increase<00:14:59.339> your 00:14:59.689 --> 00:14:59.699 align:start position:0% some resource to increase your 00:14:59.699 --> 00:15:01.730 align:start position:0% some resource to increase your confidence<00:15:00.000> in<00:15:00.360> the<00:15:00.540> project<00:15:00.720> first<00:15:01.320> thing<00:15:01.620> is 00:15:01.730 --> 00:15:01.740 align:start position:0% confidence in the project first thing is 00:15:01.740 --> 00:15:04.430 align:start position:0% confidence in the project first thing is the<00:15:01.860> best<00:15:01.980> solution<00:15:02.279> yes<00:15:03.000> and<00:15:03.300> uh<00:15:03.660> and<00:15:03.899> also<00:15:04.139> we 00:15:04.430 --> 00:15:04.440 align:start position:0% the best solution yes and uh and also we 00:15:04.440 --> 00:15:07.550 align:start position:0% the best solution yes and uh and also we found<00:15:04.680> that<00:15:05.100> so<00:15:05.839> Echidna<00:15:06.839> is<00:15:06.899> a<00:15:07.079> tool<00:15:07.440> that 00:15:07.550 --> 00:15:07.560 align:start position:0% found that so Echidna is a tool that 00:15:07.560 --> 00:15:09.949 align:start position:0% found that so Echidna is a tool that works<00:15:07.920> with<00:15:08.160> our<00:15:08.399> static<00:15:09.060> analysis<00:15:09.480> leader 00:15:09.949 --> 00:15:09.959 align:start position:0% works with our static analysis leader 00:15:09.959 --> 00:15:12.590 align:start position:0% works with our static analysis leader that<00:15:10.560> gets<00:15:10.920> value<00:15:11.220> so<00:15:11.699> you<00:15:12.120> have<00:15:12.300> in<00:15:12.480> some 00:15:12.590 --> 00:15:12.600 align:start position:0% that gets value so you have in some 00:15:12.600 --> 00:15:14.449 align:start position:0% that gets value so you have in some cases<00:15:12.959> like<00:15:13.320> let's<00:15:13.740> say<00:15:13.920> that<00:15:14.100> you<00:15:14.220> have<00:15:14.339> a 00:15:14.449 --> 00:15:14.459 align:start position:0% cases like let's say that you have a 00:15:14.459 --> 00:15:17.269 align:start position:0% cases like let's say that you have a test<00:15:14.579> that<00:15:14.820> says<00:15:15.060> if<00:15:15.660> x<00:15:16.019> equal<00:15:16.320> to<00:15:16.560> some<00:15:16.980> some 00:15:17.269 --> 00:15:17.279 align:start position:0% test that says if x equal to some some 00:15:17.279 --> 00:15:21.110 align:start position:0% test that says if x equal to some some value<00:15:17.839> some<00:15:18.839> uh<00:15:19.579> traditional<00:15:20.579> fossil 00:15:21.110 --> 00:15:21.120 align:start position:0% value some uh traditional fossil 00:15:21.120 --> 00:15:23.569 align:start position:0% value some uh traditional fossil techniques<00:15:21.600> have<00:15:22.139> hard<00:15:22.620> time<00:15:22.860> to<00:15:23.100> deal<00:15:23.220> with 00:15:23.569 --> 00:15:23.579 align:start position:0% techniques have hard time to deal with 00:15:23.579 --> 00:15:26.210 align:start position:0% techniques have hard time to deal with this<00:15:23.760> but<00:15:24.300> what<00:15:24.540> we<00:15:24.720> what<00:15:25.019> we<00:15:25.260> do<00:15:25.380> is<00:15:25.620> constant 00:15:26.210 --> 00:15:26.220 align:start position:0% this but what we what we do is constant 00:15:26.220 --> 00:15:29.150 align:start position:0% this but what we what we do is constant mining<00:15:26.639> so<00:15:26.820> we<00:15:27.000> scan<00:15:27.720> all<00:15:27.899> your<00:15:28.079> code<00:15:28.320> look<00:15:28.920> for 00:15:29.150 --> 00:15:29.160 align:start position:0% mining so we scan all your code look for 00:15:29.160 --> 00:15:31.129 align:start position:0% mining so we scan all your code look for these<00:15:29.579> magic<00:15:29.820> values<00:15:30.360> and<00:15:30.660> we<00:15:30.779> will<00:15:30.959> play 00:15:31.129 --> 00:15:31.139 align:start position:0% these magic values and we will play 00:15:31.139 --> 00:15:33.290 align:start position:0% these magic values and we will play these<00:15:31.380> magic<00:15:31.560> values<00:15:32.040> and<00:15:32.399> some<00:15:32.639> mutation<00:15:33.060> of 00:15:33.290 --> 00:15:33.300 align:start position:0% these magic values and some mutation of 00:15:33.300 --> 00:15:35.930 align:start position:0% these magic values and some mutation of that<00:15:33.480> from<00:15:34.079> time<00:15:34.260> to<00:15:34.380> time<00:15:34.620> so<00:15:35.279> or<00:15:35.459> fossil 00:15:35.930 --> 00:15:35.940 align:start position:0% that from time to time so or fossil 00:15:35.940 --> 00:15:38.210 align:start position:0% that from time to time so or fossil should<00:15:36.240> be<00:15:36.420> able<00:15:36.540> to<00:15:36.660> get<00:15:36.959> inside<00:15:37.260> the<00:15:37.740> inside 00:15:38.210 --> 00:15:38.220 align:start position:0% should be able to get inside the inside 00:15:38.220 --> 00:15:40.910 align:start position:0% should be able to get inside the inside this<00:15:38.579> if<00:15:39.180> you<00:15:39.300> if<00:15:39.660> you<00:15:39.779> if<00:15:40.139> you<00:15:40.260> have<00:15:40.440> a<00:15:40.620> test 00:15:40.910 --> 00:15:40.920 align:start position:0% this if you if you if you have a test 00:15:40.920 --> 00:15:44.090 align:start position:0% this if you if you if you have a test case<00:15:41.160> that<00:15:41.399> is<00:15:41.579> not<00:15:41.820> that<00:15:42.540> is<00:15:42.720> not<00:15:43.079> working 00:15:44.090 --> 00:15:44.100 align:start position:0% case that is not that is not working 00:15:44.100 --> 00:15:46.790 align:start position:0% case that is not that is not working please<00:15:44.760> let<00:15:45.000> us<00:15:45.180> know<00:15:45.300> and<00:15:45.540> we<00:15:45.779> can<00:15:45.899> try<00:15:46.139> to<00:15:46.320> to 00:15:46.790 --> 00:15:46.800 align:start position:0% please let us know and we can try to to 00:15:46.800 --> 00:15:48.829 align:start position:0% please let us know and we can try to to see<00:15:47.040> it<00:15:47.220> but<00:15:47.399> in<00:15:47.579> practice<00:15:47.820> it<00:15:48.300> seems<00:15:48.600> like 00:15:48.829 --> 00:15:48.839 align:start position:0% see it but in practice it seems like 00:15:48.839 --> 00:15:52.730 align:start position:0% see it but in practice it seems like some<00:15:49.680> of<00:15:49.860> the<00:15:50.220> typical<00:15:50.940> use<00:15:51.779> cases<00:15:52.139> for 00:15:52.730 --> 00:15:52.740 align:start position:0% some of the typical use cases for 00:15:52.740 --> 00:15:54.650 align:start position:0% some of the typical use cases for symbolic<00:15:53.459> execution<00:15:53.880> in<00:15:54.120> which<00:15:54.300> you<00:15:54.480> have 00:15:54.650 --> 00:15:54.660 align:start position:0% symbolic execution in which you have 00:15:54.660 --> 00:15:58.610 align:start position:0% symbolic execution in which you have constant<00:15:55.260> uh<00:15:56.040> Magic<00:15:56.459> values<00:15:57.120> to<00:15:57.600> to<00:15:58.139> look<00:15:58.440> for 00:15:58.610 --> 00:15:58.620 align:start position:0% constant uh Magic values to to look for 00:15:58.620 --> 00:16:01.910 align:start position:0% constant uh Magic values to to look for they<00:15:59.100> can<00:15:59.339> be<00:15:59.519> replaced<00:16:00.240> by<00:16:00.660> uh<00:16:01.560> constant 00:16:01.910 --> 00:16:01.920 align:start position:0% they can be replaced by uh constant 00:16:01.920 --> 00:16:13.129 align:start position:0% they can be replaced by uh constant mining<00:16:02.220> extraction 00:16:13.129 --> 00:16:13.139 align:start position:0% 00:16:13.139 --> 00:16:15.410 align:start position:0% how<00:16:13.860> many<00:16:14.040> of<00:16:14.220> you<00:16:14.339> have<00:16:14.639> issued<00:16:15.180> to<00:16:15.240> install 00:16:15.410 --> 00:16:15.420 align:start position:0% how many of you have issued to install 00:16:15.420 --> 00:16:23.889 align:start position:0% how many of you have issued to install Akin<00:16:15.899> now<00:16:16.079> to<00:16:16.260> one<00:16:16.500> like<00:16:16.620> the<00:16:16.800> exercise 00:16:23.889 --> 00:16:23.899 align:start position:0% 00:16:23.899 --> 00:16:26.269 align:start position:0% how<00:16:24.899> many<00:16:25.079> of<00:16:25.260> you<00:16:25.380> have<00:16:25.740> issue<00:16:26.160> like 00:16:26.269 --> 00:16:26.279 align:start position:0% how many of you have issue like 00:16:26.279 --> 00:16:28.490 align:start position:0% how many of you have issue like installing<00:16:26.760> akina<00:16:27.240> or<00:16:27.839> opening<00:16:28.260> like<00:16:28.380> the 00:16:28.490 --> 00:16:28.500 align:start position:0% installing akina or opening like the 00:16:28.500 --> 00:16:31.490 align:start position:0% installing akina or opening like the different<00:16:28.680> exercise 00:16:31.490 --> 00:16:31.500 align:start position:0% 00:16:31.500 --> 00:16:37.189 align:start position:0% okay 00:16:37.189 --> 00:16:37.199 align:start position:0% 00:16:37.199 --> 00:16:39.889 align:start position:0% uh<00:16:37.980> no<00:16:38.160> you<00:16:38.459> you<00:16:38.519> you<00:16:38.699> you<00:16:38.940> you<00:16:39.300> have<00:16:39.660> to<00:16:39.779> open 00:16:39.889 --> 00:16:39.899 align:start position:0% uh no you you you you you have to open 00:16:39.899 --> 00:16:42.970 align:start position:0% uh no you you you you you have to open your<00:16:40.139> terminal<00:16:40.500> and<00:16:41.160> a<00:16:41.399> kidnap<00:16:41.880> will 00:16:42.970 --> 00:16:42.980 align:start position:0% your terminal and a kidnap will 00:16:42.980 --> 00:16:46.249 align:start position:0% your terminal and a kidnap will deploy<00:16:43.980> the<00:16:44.579> sort<00:16:45.180> of<00:16:45.300> unit<00:16:45.779> is<00:16:46.139> still 00:16:46.249 --> 00:16:46.259 align:start position:0% deploy the sort of unit is still 00:16:46.259 --> 00:16:48.410 align:start position:0% deploy the sort of unit is still installed<00:16:47.040> the<00:16:47.220> tool<00:16:47.459> and<00:16:47.639> when<00:16:47.820> you<00:16:48.000> put<00:16:48.180> like 00:16:48.410 --> 00:16:48.420 align:start position:0% installed the tool and when you put like 00:16:48.420 --> 00:16:51.590 align:start position:0% installed the tool and when you put like equipment<00:16:49.139> you<00:16:50.040> cannot<00:16:50.399> test<00:16:50.639> some<00:16:51.120> contract 00:16:51.590 --> 00:16:51.600 align:start position:0% equipment you cannot test some contract 00:16:51.600 --> 00:16:54.410 align:start position:0% equipment you cannot test some contract it<00:16:52.259> will<00:16:52.440> compile<00:16:52.860> it<00:16:53.100> running<00:16:53.820> inside<00:16:54.180> the 00:16:54.410 --> 00:16:54.420 align:start position:0% it will compile it running inside the 00:16:54.420 --> 00:16:56.930 align:start position:0% it will compile it running inside the simulated<00:16:55.040> blockchain<00:16:56.040> and<00:16:56.519> give<00:16:56.699> you<00:16:56.820> the 00:16:56.930 --> 00:16:56.940 align:start position:0% simulated blockchain and give you the 00:16:56.940 --> 00:16:58.730 align:start position:0% simulated blockchain and give you the answer<00:16:57.060> so<00:16:57.360> you<00:16:57.660> don't<00:16:57.779> need<00:16:58.079> to<00:16:58.259> connect<00:16:58.440> into 00:16:58.730 --> 00:16:58.740 align:start position:0% answer so you don't need to connect into 00:16:58.740 --> 00:17:03.290 align:start position:0% answer so you don't need to connect into something 00:17:03.290 --> 00:17:03.300 align:start position:0% 00:17:03.300 --> 00:17:06.710 align:start position:0% uh<00:17:04.020> so<00:17:04.199> yeah<00:17:04.439> going<00:17:04.799> to<00:17:05.100> them<00:17:05.339> into<00:17:06.299> the 00:17:06.710 --> 00:17:06.720 align:start position:0% uh so yeah going to them into the 00:17:06.720 --> 00:17:10.069 align:start position:0% uh so yeah going to them into the repository<00:17:07.380> and<00:17:07.919> it<00:17:08.100> says<00:17:08.339> like<00:17:08.579> yeah 00:17:10.069 --> 00:17:10.079 align:start position:0% repository and it says like yeah 00:17:10.079 --> 00:17:11.870 align:start position:0% repository and it says like yeah yeah<00:17:10.140> so<00:17:10.620> yeah<00:17:10.980> this<00:17:11.220> is<00:17:11.339> like<00:17:11.579> your 00:17:11.870 --> 00:17:11.880 align:start position:0% yeah so yeah this is like your 00:17:11.880 --> 00:17:15.049 align:start position:0% yeah so yeah this is like your traditional<00:17:12.600> one<00:17:12.839> but<00:17:13.339> if<00:17:14.339> you<00:17:14.520> go<00:17:14.640> into<00:17:14.760> the 00:17:15.049 --> 00:17:15.059 align:start position:0% traditional one but if you go into the 00:17:15.059 --> 00:17:19.850 align:start position:0% traditional one but if you go into the Devcon<00:17:15.780> branch<00:17:16.459> that<00:17:17.459> is<00:17:17.579> sorry 00:17:19.850 --> 00:17:19.860 align:start position:0% Devcon branch that is sorry 00:17:19.860 --> 00:17:22.429 align:start position:0% Devcon branch that is sorry yeah<00:17:20.100> so<00:17:20.699> it's<00:17:20.880> it's<00:17:21.059> it<00:17:21.179> has<00:17:21.660> more<00:17:22.079> specific 00:17:22.429 --> 00:17:22.439 align:start position:0% yeah so it's it's it has more specific 00:17:22.439 --> 00:17:24.409 align:start position:0% yeah so it's it's it has more specific yeah<00:17:22.740> so<00:17:22.980> so<00:17:23.220> over<00:17:23.520> there<00:17:23.760> you<00:17:23.939> said<00:17:24.059> like<00:17:24.240> if 00:17:24.409 --> 00:17:24.419 align:start position:0% yeah so so over there you said like if 00:17:24.419 --> 00:17:26.329 align:start position:0% yeah so so over there you said like if you're<00:17:24.600> using<00:17:24.900> Mac<00:17:25.020> you<00:17:25.260> can<00:17:25.380> do<00:17:25.500> that<00:17:25.740> that<00:17:25.980> or 00:17:26.329 --> 00:17:26.339 align:start position:0% you're using Mac you can do that that or 00:17:26.339 --> 00:17:28.130 align:start position:0% you're using Mac you can do that that or you<00:17:26.579> can<00:17:26.699> download 00:17:28.130 --> 00:17:28.140 align:start position:0% you can download 00:17:28.140 --> 00:17:29.510 align:start position:0% you can download okay<00:17:28.620> yeah 00:17:29.510 --> 00:17:29.520 align:start position:0% okay yeah 00:17:29.520 --> 00:17:32.210 align:start position:0% okay yeah okay<00:17:30.120> yeah<00:17:30.600> so<00:17:30.900> I<00:17:31.080> wanted<00:17:31.320> to<00:17:31.559> highlight<00:17:31.860> one 00:17:32.210 --> 00:17:32.220 align:start position:0% okay yeah so I wanted to highlight one 00:17:32.220 --> 00:17:34.310 align:start position:0% okay yeah so I wanted to highlight one one<00:17:32.520> little<00:17:32.820> feature<00:17:33.540> that<00:17:33.780> we<00:17:33.900> are<00:17:34.020> testing 00:17:34.310 --> 00:17:34.320 align:start position:0% one little feature that we are testing 00:17:34.320 --> 00:17:35.990 align:start position:0% one little feature that we are testing on<00:17:34.500> Echidna<00:17:35.160> that<00:17:35.340> is 00:17:35.990 --> 00:17:36.000 align:start position:0% on Echidna that is 00:17:36.000 --> 00:17:38.810 align:start position:0% on Echidna that is that<00:17:36.660> is<00:17:36.900> also<00:17:37.140> used<00:17:37.260> in<00:17:37.500> fasting<00:17:37.919> but<00:17:38.100> instead 00:17:38.810 --> 00:17:38.820 align:start position:0% that is also used in fasting but instead 00:17:38.820 --> 00:17:41.810 align:start position:0% that is also used in fasting but instead of<00:17:38.940> testing<00:17:39.660> a<00:17:40.140> property<00:17:40.559> where<00:17:41.160> we<00:17:41.400> are<00:17:41.640> doing 00:17:41.810 --> 00:17:41.820 align:start position:0% of testing a property where we are doing 00:17:41.820 --> 00:17:44.210 align:start position:0% of testing a property where we are doing minimization<00:17:42.480> or<00:17:42.840> maximization<00:17:43.320> of<00:17:43.799> some 00:17:44.210 --> 00:17:44.220 align:start position:0% minimization or maximization of some 00:17:44.220 --> 00:17:47.570 align:start position:0% minimization or maximization of some value<00:17:44.460> so<00:17:45.360> this<00:17:45.660> is<00:17:45.840> an<00:17:46.080> a<00:17:46.320> new<00:17:46.620> thing<00:17:46.799> that<00:17:47.220> we 00:17:47.570 --> 00:17:47.580 align:start position:0% value so this is an a new thing that we 00:17:47.580 --> 00:17:50.029 align:start position:0% value so this is an a new thing that we are<00:17:47.760> that<00:17:48.179> we<00:17:48.480> are<00:17:48.600> testing<00:17:49.080> it<00:17:49.500> is<00:17:49.740> not 00:17:50.029 --> 00:17:50.039 align:start position:0% are that we are testing it is not 00:17:50.039 --> 00:17:52.430 align:start position:0% are that we are testing it is not property<00:17:50.520> based<00:17:50.940> testing<00:17:51.299> but<00:17:52.080> it's<00:17:52.200> it's 00:17:52.430 --> 00:17:52.440 align:start position:0% property based testing but it's it's 00:17:52.440 --> 00:17:53.990 align:start position:0% property based testing but it's it's something<00:17:52.799> it's<00:17:53.160> something<00:17:53.400> that<00:17:53.700> we<00:17:53.880> are 00:17:53.990 --> 00:17:54.000 align:start position:0% something it's something that we are 00:17:54.000 --> 00:17:55.850 align:start position:0% something it's something that we are trying<00:17:54.240> that<00:17:54.720> we<00:17:54.840> are<00:17:54.960> trying<00:17:55.080> to<00:17:55.260> push<00:17:55.440> so<00:17:55.620> if 00:17:55.850 --> 00:17:55.860 align:start position:0% trying that we are trying to push so if 00:17:55.860 --> 00:17:59.210 align:start position:0% trying that we are trying to push so if you<00:17:55.980> want<00:17:56.220> to<00:17:56.400> know<00:17:56.640> if<00:17:57.539> a<00:17:57.720> user<00:17:58.080> is<00:17:58.320> it's 00:17:59.210 --> 00:17:59.220 align:start position:0% you want to know if a user is it's 00:17:59.220 --> 00:18:03.169 align:start position:0% you want to know if a user is it's capable<00:17:59.700> of<00:18:00.080> uh<00:18:01.080> extracting<00:18:01.799> tokens<00:18:02.760> from 00:18:03.169 --> 00:18:03.179 align:start position:0% capable of uh extracting tokens from 00:18:03.179 --> 00:18:05.390 align:start position:0% capable of uh extracting tokens from your<00:18:03.419> system<00:18:03.600> without<00:18:04.140> you<00:18:04.500> to<00:18:04.679> realize<00:18:04.980> you 00:18:05.390 --> 00:18:05.400 align:start position:0% your system without you to realize you 00:18:05.400 --> 00:18:08.210 align:start position:0% your system without you to realize you can<00:18:05.460> use<00:18:05.700> that<00:18:05.940> feature<00:18:06.299> just<00:18:06.960> saying<00:18:07.440> uh<00:18:08.100> Hey 00:18:08.210 --> 00:18:08.220 align:start position:0% can use that feature just saying uh Hey 00:18:08.220 --> 00:18:10.250 align:start position:0% can use that feature just saying uh Hey Echidna<00:18:08.640> can<00:18:08.880> you<00:18:08.940> maximize<00:18:09.419> this<00:18:09.720> balance<00:18:10.080> of 00:18:10.250 --> 00:18:10.260 align:start position:0% Echidna can you maximize this balance of 00:18:10.260 --> 00:18:12.470 align:start position:0% Echidna can you maximize this balance of this<00:18:10.440> account<00:18:10.620> so<00:18:11.160> it<00:18:11.340> will<00:18:11.520> try<00:18:11.700> to<00:18:11.880> generate 00:18:12.470 --> 00:18:12.480 align:start position:0% this account so it will try to generate 00:18:12.480 --> 00:18:15.770 align:start position:0% this account so it will try to generate you<00:18:12.660> the<00:18:13.020> maximum<00:18:13.880> sequence<00:18:14.880> so<00:18:15.419> it's<00:18:15.539> it's 00:18:15.770 --> 00:18:15.780 align:start position:0% you the maximum sequence so it's it's 00:18:15.780 --> 00:18:18.230 align:start position:0% you the maximum sequence so it's it's it's<00:18:15.900> a<00:18:16.559> little<00:18:16.559> bit<00:18:16.679> outside<00:18:16.919> this<00:18:17.280> but<00:18:17.760> uh 00:18:18.230 --> 00:18:18.240 align:start position:0% it's a little bit outside this but uh 00:18:18.240 --> 00:18:22.510 align:start position:0% it's a little bit outside this but uh it's<00:18:18.780> something<00:18:18.960> that<00:18:19.260> we<00:18:19.440> wanted<00:18:19.860> to<00:18:20.100> mention 00:18:22.510 --> 00:18:22.520 align:start position:0% 00:18:22.520 --> 00:18:24.850 align:start position:0% okay<00:18:23.520> so 00:18:24.850 --> 00:18:24.860 align:start position:0% okay so 00:18:24.860 --> 00:18:29.570 align:start position:0% okay so our<00:18:25.860> Target<00:18:26.240> here<00:18:27.240> is<00:18:27.600> a<00:18:27.840> token 00:18:29.570 --> 00:18:29.580 align:start position:0% our Target here is a token 00:18:29.580 --> 00:18:32.570 align:start position:0% our Target here is a token um<00:18:29.700> it<00:18:30.000> has<00:18:30.179> a<00:18:30.299> transfer<00:18:30.660> function<00:18:31.400> like<00:18:32.400> a 00:18:32.570 --> 00:18:32.580 align:start position:0% um it has a transfer function like a 00:18:32.580 --> 00:18:34.430 align:start position:0% um it has a transfer function like a classic<00:18:32.700> Crosshair<00:18:33.179> function<00:18:33.539> you<00:18:33.900> enable<00:18:34.320> it 00:18:34.430 --> 00:18:34.440 align:start position:0% classic Crosshair function you enable it 00:18:34.440 --> 00:18:37.310 align:start position:0% classic Crosshair function you enable it from<00:18:34.679> a<00:18:34.860> possible<00:18:35.400> contract<00:18:36.240> which<00:18:36.539> is<00:18:36.840> like<00:18:37.080> a 00:18:37.310 --> 00:18:37.320 align:start position:0% from a possible contract which is like a 00:18:37.320 --> 00:18:40.250 align:start position:0% from a possible contract which is like a basic<00:18:37.679> possible<00:18:38.340> system 00:18:40.250 --> 00:18:40.260 align:start position:0% basic possible system 00:18:40.260 --> 00:18:43.730 align:start position:0% basic possible system and<00:18:41.100> what<00:18:41.700> we<00:18:41.940> want<00:18:42.120> to<00:18:42.240> try<00:18:42.539> to<00:18:42.720> do<00:18:42.960> here<00:18:43.260> is<00:18:43.559> to 00:18:43.730 --> 00:18:43.740 align:start position:0% and what we want to try to do here is to 00:18:43.740 --> 00:18:46.850 align:start position:0% and what we want to try to do here is to create<00:18:43.919> the<00:18:44.160> invariants<00:18:44.700> such<00:18:45.419> as<00:18:45.600> no<00:18:46.440> user 00:18:46.850 --> 00:18:46.860 align:start position:0% create the invariants such as no user 00:18:46.860 --> 00:18:48.950 align:start position:0% create the invariants such as no user should<00:18:47.160> have<00:18:47.340> a<00:18:47.520> balance<00:18:47.820> above<00:18:48.480> the<00:18:48.660> total 00:18:48.950 --> 00:18:48.960 align:start position:0% should have a balance above the total 00:18:48.960 --> 00:18:50.330 align:start position:0% should have a balance above the total Supply 00:18:50.330 --> 00:18:50.340 align:start position:0% Supply 00:18:50.340 --> 00:18:52.490 align:start position:0% Supply test<00:18:50.820> the<00:18:51.179> tokens<00:18:51.480> where<00:18:51.840> we<00:18:52.020> are<00:18:52.140> going<00:18:52.260> to<00:18:52.380> do 00:18:52.490 --> 00:18:52.500 align:start position:0% test the tokens where we are going to do 00:18:52.500 --> 00:18:54.950 align:start position:0% test the tokens where we are going to do it<00:18:52.620> is<00:18:52.799> that<00:18:52.980> we<00:18:53.160> are<00:18:53.340> going<00:18:53.400> to<00:18:53.520> inherit<00:18:54.120> the 00:18:54.950 --> 00:18:54.960 align:start position:0% it is that we are going to inherit the 00:18:54.960 --> 00:18:56.930 align:start position:0% it is that we are going to inherit the token<00:18:55.380> or<00:18:55.620> Target<00:18:55.860> we<00:18:56.400> are<00:18:56.520> going<00:18:56.580> to<00:18:56.700> create 00:18:56.930 --> 00:18:56.940 align:start position:0% token or Target we are going to create 00:18:56.940 --> 00:18:59.570 align:start position:0% token or Target we are going to create the<00:18:57.179> contract<00:18:57.539> test<00:18:57.720> token<00:18:58.620> we<00:18:59.160> are<00:18:59.340> going<00:18:59.460> to 00:18:59.570 --> 00:18:59.580 align:start position:0% the contract test token we are going to 00:18:59.580 --> 00:19:02.270 align:start position:0% the contract test token we are going to initialize<00:19:00.240> the<00:19:00.840> balance<00:19:01.200> of<00:19:01.559> the<00:19:01.740> colors<00:19:02.100> of 00:19:02.270 --> 00:19:02.280 align:start position:0% initialize the balance of the colors of 00:19:02.280 --> 00:19:06.350 align:start position:0% initialize the balance of the colors of the<00:19:02.460> first<00:19:02.640> user<00:19:03.140> to<00:19:04.140> 10<00:19:05.340> 000 00:19:06.350 --> 00:19:06.360 align:start position:0% the first user to 10 000 00:19:06.360 --> 00:19:08.210 align:start position:0% the first user to 10 000 and<00:19:06.720> this<00:19:06.840> is<00:19:06.960> an<00:19:07.080> initialization<00:19:07.559> so<00:19:07.860> you<00:19:08.100> are 00:19:08.210 --> 00:19:08.220 align:start position:0% and this is an initialization so you are 00:19:08.220 --> 00:19:10.669 align:start position:0% and this is an initialization so you are creating<00:19:08.460> a<00:19:08.640> token<00:19:09.000> there<00:19:09.419> is<00:19:09.600> 10<00:19:10.080> 000<00:19:10.140> in<00:19:10.440> one 00:19:10.669 --> 00:19:10.679 align:start position:0% creating a token there is 10 000 in one 00:19:10.679 --> 00:19:11.870 align:start position:0% creating a token there is 10 000 in one address 00:19:11.870 --> 00:19:11.880 align:start position:0% address 00:19:11.880 --> 00:19:16.850 align:start position:0% address and<00:19:12.419> no<00:19:12.660> the<00:19:13.500> invariant<00:19:14.039> is<00:19:14.460> simply<00:19:14.880> that 00:19:16.850 --> 00:19:16.860 align:start position:0% and no the invariant is simply that 00:19:16.860 --> 00:19:20.330 align:start position:0% and no the invariant is simply that um<00:19:16.919> no<00:19:17.820> user<00:19:18.179> so<00:19:18.600> the<00:19:18.780> user<00:19:19.080> should<00:19:20.039> not<00:19:20.160> have 00:19:20.330 --> 00:19:20.340 align:start position:0% um no user so the user should not have 00:19:20.340 --> 00:19:23.450 align:start position:0% um no user so the user should not have more<00:19:20.520> than<00:19:20.700> 10<00:19:21.059> 000<00:19:21.120> okay<00:19:21.480> again<00:19:22.200> you<00:19:22.860> deploy<00:19:23.280> a 00:19:23.450 --> 00:19:23.460 align:start position:0% more than 10 000 okay again you deploy a 00:19:23.460 --> 00:19:26.870 align:start position:0% more than 10 000 okay again you deploy a token<00:19:24.120> 10<00:19:24.840> 000<00:19:24.840> token<00:19:25.260> to<00:19:25.440> one<00:19:25.740> user<00:19:26.100> this<00:19:26.520> user 00:19:26.870 --> 00:19:26.880 align:start position:0% token 10 000 token to one user this user 00:19:26.880 --> 00:19:29.090 align:start position:0% token 10 000 token to one user this user should<00:19:27.120> never<00:19:27.299> have<00:19:27.539> like<00:19:27.840> 20 00:19:29.090 --> 00:19:29.100 align:start position:0% should never have like 20 00:19:29.100 --> 00:19:32.150 align:start position:0% should never have like 20 000<00:19:29.220> token<00:19:29.640> all<00:19:29.880> right 00:19:32.150 --> 00:19:32.160 align:start position:0% 00:19:32.160 --> 00:19:34.610 align:start position:0% and<00:19:32.880> if<00:19:33.120> you<00:19:33.240> want<00:19:33.360> this<00:19:33.600> with<00:19:33.780> a<00:19:33.900> kidnap<00:19:34.260> a 00:19:34.610 --> 00:19:34.620 align:start position:0% and if you want this with a kidnap a 00:19:34.620 --> 00:19:37.070 align:start position:0% and if you want this with a kidnap a Kina<00:19:34.860> is<00:19:35.100> going<00:19:35.220> to<00:19:35.340> tell<00:19:35.700> you<00:19:35.880> that<00:19:36.720> this 00:19:37.070 --> 00:19:37.080 align:start position:0% Kina is going to tell you that this 00:19:37.080 --> 00:19:39.409 align:start position:0% Kina is going to tell you that this invariant<00:19:37.620> is<00:19:37.860> property<00:19:38.400> on<00:19:38.820> total<00:19:39.240> Supply 00:19:39.409 --> 00:19:39.419 align:start position:0% invariant is property on total Supply 00:19:39.419 --> 00:19:42.529 align:start position:0% invariant is property on total Supply was<00:19:40.260> broken<00:19:40.500> it<00:19:41.100> failed<00:19:41.460> and<00:19:42.059> it's<00:19:42.179> going<00:19:42.419> to 00:19:42.529 --> 00:19:42.539 align:start position:0% was broken it failed and it's going to 00:19:42.539 --> 00:19:44.029 align:start position:0% was broken it failed and it's going to tell<00:19:42.720> you<00:19:42.900> how 00:19:44.029 --> 00:19:44.039 align:start position:0% tell you how 00:19:44.039 --> 00:19:47.330 align:start position:0% tell you how and<00:19:44.760> the<00:19:44.940> answer<00:19:45.059> is<00:19:45.419> that<00:19:45.600> you<00:19:46.260> just<00:19:46.500> call<00:19:46.860> the 00:19:47.330 --> 00:19:47.340 align:start position:0% and the answer is that you just call the 00:19:47.340 --> 00:19:49.610 align:start position:0% and the answer is that you just call the function<00:19:47.640> transfer<00:19:48.299> with<00:19:49.080> the<00:19:49.200> destination 00:19:49.610 --> 00:19:49.620 align:start position:0% function transfer with the destination 00:19:49.620 --> 00:19:52.390 align:start position:0% function transfer with the destination address<00:19:49.860> 0<00:19:50.600> and 00:19:52.390 --> 00:19:52.400 align:start position:0% address 0 and 00:19:52.400 --> 00:19:56.750 align:start position:0% address 0 and 1093<00:19:53.400> token<00:19:54.360> so<00:19:54.780> what<00:19:54.960> happened<00:19:55.140> here 00:19:56.750 --> 00:19:56.760 align:start position:0% 1093 token so what happened here 00:19:56.760 --> 00:19:59.990 align:start position:0% 1093 token so what happened here this<00:19:57.720> was<00:19:57.900> compiled<00:19:58.380> with<00:19:58.559> solidity<00:19:59.039> 0.7<00:19:59.700> so 00:19:59.990 --> 00:20:00.000 align:start position:0% this was compiled with solidity 0.7 so 00:20:00.000 --> 00:20:01.669 align:start position:0% this was compiled with solidity 0.7 so there<00:20:00.240> is<00:20:00.360> no<00:20:00.539> overflow<00:20:01.020> and<00:20:01.260> underflow 00:20:01.669 --> 00:20:01.679 align:start position:0% there is no overflow and underflow 00:20:01.679 --> 00:20:02.750 align:start position:0% there is no overflow and underflow protection 00:20:02.750 --> 00:20:02.760 align:start position:0% protection 00:20:02.760 --> 00:20:04.730 align:start position:0% protection so<00:20:03.179> there<00:20:03.360> was<00:20:03.539> an<00:20:03.600> underflow<00:20:04.080> problem<00:20:04.320> here 00:20:04.730 --> 00:20:04.740 align:start position:0% so there was an underflow problem here 00:20:04.740 --> 00:20:07.490 align:start position:0% so there was an underflow problem here where<00:20:05.100> if<00:20:05.520> you<00:20:05.640> try<00:20:05.940> to<00:20:06.120> send<00:20:06.840> more<00:20:07.140> more 00:20:07.490 --> 00:20:07.500 align:start position:0% where if you try to send more more 00:20:07.500 --> 00:20:09.529 align:start position:0% where if you try to send more more tokens<00:20:07.860> that<00:20:07.980> you<00:20:08.100> have<00:20:08.220> a<00:20:08.280> new<00:20:08.400> balance<00:20:08.700> the 00:20:09.529 --> 00:20:09.539 align:start position:0% tokens that you have a new balance the 00:20:09.539 --> 00:20:11.270 align:start position:0% tokens that you have a new balance the balance<00:20:09.780> is<00:20:09.960> going<00:20:10.080> to<00:20:10.200> render<00:20:10.440> flow<00:20:10.860> and<00:20:11.039> you 00:20:11.270 --> 00:20:11.280 align:start position:0% balance is going to render flow and you 00:20:11.280 --> 00:20:13.370 align:start position:0% balance is going to render flow and you know<00:20:11.400> you<00:20:11.580> have<00:20:11.700> a<00:20:11.820> really<00:20:11.940> large 00:20:13.370 --> 00:20:13.380 align:start position:0% know you have a really large 00:20:13.380 --> 00:20:15.950 align:start position:0% know you have a really large balance<00:20:14.100> something<00:20:14.820> which<00:20:15.120> is<00:20:15.299> interesting 00:20:15.950 --> 00:20:15.960 align:start position:0% balance something which is interesting 00:20:15.960 --> 00:20:18.770 align:start position:0% balance something which is interesting here<00:20:16.200> is<00:20:16.919> that<00:20:17.100> we<00:20:17.460> Define<00:20:17.760> the<00:20:18.179> invariance 00:20:18.770 --> 00:20:18.780 align:start position:0% here is that we Define the invariance 00:20:18.780 --> 00:20:20.450 align:start position:0% here is that we Define the invariance you<00:20:19.559> know 00:20:20.450 --> 00:20:20.460 align:start position:0% you know 00:20:20.460 --> 00:20:22.669 align:start position:0% you know without<00:20:21.000> looking<00:20:21.840> at<00:20:22.080> the<00:20:22.260> code<00:20:22.440> without 00:20:22.669 --> 00:20:22.679 align:start position:0% without looking at the code without 00:20:22.679 --> 00:20:24.169 align:start position:0% without looking at the code without looking<00:20:22.980> at<00:20:23.220> the<00:20:23.340> function<00:20:23.640> we<00:20:23.880> were<00:20:24.059> not 00:20:24.169 --> 00:20:24.179 align:start position:0% looking at the function we were not 00:20:24.179 --> 00:20:25.850 align:start position:0% looking at the function we were not looking<00:20:24.419> is<00:20:24.840> there<00:20:25.020> any<00:20:25.140> issue<00:20:25.559> in<00:20:25.740> the 00:20:25.850 --> 00:20:25.860 align:start position:0% looking is there any issue in the 00:20:25.860 --> 00:20:27.529 align:start position:0% looking is there any issue in the transfer<00:20:26.280> function<00:20:26.580> we<00:20:26.820> just<00:20:27.000> Define<00:20:27.240> an 00:20:27.529 --> 00:20:27.539 align:start position:0% transfer function we just Define an 00:20:27.539 --> 00:20:29.630 align:start position:0% transfer function we just Define an invariance<00:20:28.140> and<00:20:28.620> by<00:20:28.799> doing<00:20:29.039> so<00:20:29.280> we<00:20:29.520> can 00:20:29.630 --> 00:20:29.640 align:start position:0% invariance and by doing so we can 00:20:29.640 --> 00:20:31.070 align:start position:0% invariance and by doing so we can realize<00:20:30.059> that<00:20:30.179> there<00:20:30.360> is<00:20:30.480> a<00:20:30.600> bug<00:20:30.720> in<00:20:30.960> the 00:20:31.070 --> 00:20:31.080 align:start position:0% realize that there is a bug in the 00:20:31.080 --> 00:20:33.529 align:start position:0% realize that there is a bug in the transfer<00:20:31.440> function 00:20:33.529 --> 00:20:33.539 align:start position:0% transfer function 00:20:33.539 --> 00:20:35.930 align:start position:0% transfer function um<00:20:33.660> so<00:20:33.900> this<00:20:34.140> is<00:20:34.320> a<00:20:34.620> kind<00:20:34.799> of<00:20:34.919> a<00:20:35.160> nice 00:20:35.930 --> 00:20:35.940 align:start position:0% um so this is a kind of a nice 00:20:35.940 --> 00:20:38.390 align:start position:0% um so this is a kind of a nice a<00:20:36.539> way<00:20:36.840> of<00:20:37.020> trying<00:20:37.140> to<00:20:37.320> find<00:20:37.500> bugs<00:20:37.919> because<00:20:38.039> you 00:20:38.390 --> 00:20:38.400 align:start position:0% a way of trying to find bugs because you 00:20:38.400 --> 00:20:40.070 align:start position:0% a way of trying to find bugs because you don't<00:20:38.580> look<00:20:38.820> at<00:20:39.059> the<00:20:39.240> individual<00:20:39.720> function 00:20:40.070 --> 00:20:40.080 align:start position:0% don't look at the individual function 00:20:40.080 --> 00:20:41.210 align:start position:0% don't look at the individual function necessarily<00:20:40.620> you<00:20:40.860> can<00:20:40.980> just<00:20:41.100> Define 00:20:41.210 --> 00:20:41.220 align:start position:0% necessarily you can just Define 00:20:41.220 --> 00:20:43.669 align:start position:0% necessarily you can just Define invariant<00:20:41.880> and<00:20:42.299> the<00:20:42.539> further<00:20:43.200> is<00:20:43.380> going<00:20:43.559> to 00:20:43.669 --> 00:20:43.679 align:start position:0% invariant and the further is going to 00:20:43.679 --> 00:20:47.690 align:start position:0% invariant and the further is going to try<00:20:43.860> to<00:20:43.980> break<00:20:44.160> the<00:20:44.340> environment<00:20:44.700> for<00:20:44.880> you 00:20:47.690 --> 00:20:47.700 align:start position:0% 00:20:47.700 --> 00:20:53.090 align:start position:0% does<00:20:48.059> that<00:20:48.179> make<00:20:48.419> sense<00:20:48.539> any<00:20:49.200> question<00:20:49.500> yeah 00:20:53.090 --> 00:20:53.100 align:start position:0% 00:20:53.100 --> 00:20:54.169 align:start position:0% okay 00:20:54.169 --> 00:20:54.179 align:start position:0% okay 00:20:54.179 --> 00:20:56.150 align:start position:0% okay so 00:20:56.150 --> 00:20:56.160 align:start position:0% so 00:20:56.160 --> 00:20:59.630 align:start position:0% so okay<00:20:56.520> so<00:20:56.760> the<00:20:57.000> question<00:20:57.299> is<00:20:58.080> does<00:20:58.860> it<00:20:59.100> execute 00:20:59.630 --> 00:20:59.640 align:start position:0% okay so the question is does it execute 00:20:59.640 --> 00:21:01.730 align:start position:0% okay so the question is does it execute a<00:20:59.820> specific<00:21:00.179> function<00:21:00.600> or<00:21:00.960> how<00:21:01.320> does<00:21:01.500> it<00:21:01.620> know 00:21:01.730 --> 00:21:01.740 align:start position:0% a specific function or how does it know 00:21:01.740 --> 00:21:04.130 align:start position:0% a specific function or how does it know which<00:21:01.919> function<00:21:02.220> to<00:21:02.460> curve<00:21:02.880> the<00:21:03.600> answer<00:21:03.720> that 00:21:04.130 --> 00:21:04.140 align:start position:0% which function to curve the answer that 00:21:04.140 --> 00:21:05.510 align:start position:0% which function to curve the answer that is<00:21:04.260> going<00:21:04.380> to<00:21:04.440> call<00:21:04.620> everything 00:21:05.510 --> 00:21:05.520 align:start position:0% is going to call everything 00:21:05.520 --> 00:21:07.730 align:start position:0% is going to call everything so<00:21:05.940> in<00:21:06.059> this<00:21:06.240> token<00:21:06.600> if<00:21:06.960> you<00:21:07.080> look<00:21:07.200> at<00:21:07.380> like<00:21:07.559> the 00:21:07.730 --> 00:21:07.740 align:start position:0% so in this token if you look at like the 00:21:07.740 --> 00:21:09.470 align:start position:0% so in this token if you look at like the word<00:21:08.100> source<00:21:08.520> code<00:21:08.580> you<00:21:08.880> have<00:21:09.000> a<00:21:09.120> transfer 00:21:09.470 --> 00:21:09.480 align:start position:0% word source code you have a transfer 00:21:09.480 --> 00:21:12.289 align:start position:0% word source code you have a transfer function<00:21:09.780> possible<00:21:10.320> function<00:21:10.799> and<00:21:11.100> like<00:21:11.580> some 00:21:12.289 --> 00:21:12.299 align:start position:0% function possible function and like some 00:21:12.299 --> 00:21:13.970 align:start position:0% function possible function and like some additional<00:21:12.600> function<00:21:12.900> so<00:21:13.140> the<00:21:13.500> federal<00:21:13.679> is 00:21:13.970 --> 00:21:13.980 align:start position:0% additional function so the federal is 00:21:13.980 --> 00:21:15.950 align:start position:0% additional function so the federal is just<00:21:14.100> going<00:21:14.280> to<00:21:14.400> call<00:21:14.640> everything 00:21:15.950 --> 00:21:15.960 align:start position:0% just going to call everything 00:21:15.960 --> 00:21:17.270 align:start position:0% just going to call everything and 00:21:17.270 --> 00:21:17.280 align:start position:0% and 00:21:17.280 --> 00:21:19.430 align:start position:0% and everything<00:21:17.760> external<00:21:18.299> or<00:21:18.539> public<00:21:18.720> like 00:21:19.430 --> 00:21:19.440 align:start position:0% everything external or public like 00:21:19.440 --> 00:21:28.250 align:start position:0% everything external or public like everything<00:21:19.679> that<00:21:20.039> a<00:21:20.280> user<00:21:20.580> can<00:21:20.760> call 00:21:28.250 --> 00:21:28.260 align:start position:0% 00:21:28.260 --> 00:21:31.190 align:start position:0% okay<00:21:28.740> the<00:21:29.340> question<00:21:29.580> is<00:21:30.120> if<00:21:30.419> you<00:21:30.600> have<00:21:30.780> a<00:21:31.020> very 00:21:31.190 --> 00:21:31.200 align:start position:0% okay the question is if you have a very 00:21:31.200 --> 00:21:33.169 align:start position:0% okay the question is if you have a very large<00:21:31.500> token<00:21:32.039> or<00:21:32.159> very<00:21:32.400> large<00:21:32.580> contract<00:21:33.000> you 00:21:33.169 --> 00:21:33.179 align:start position:0% large token or very large contract you 00:21:33.179 --> 00:21:35.029 align:start position:0% large token or very large contract you have<00:21:33.360> a<00:21:33.480> lot<00:21:33.600> of<00:21:33.780> function 00:21:35.029 --> 00:21:35.039 align:start position:0% have a lot of function 00:21:35.039 --> 00:21:36.649 align:start position:0% have a lot of function so<00:21:35.340> here<00:21:35.520> you<00:21:35.640> can<00:21:35.760> take<00:21:35.880> different<00:21:36.059> approach 00:21:36.649 --> 00:21:36.659 align:start position:0% so here you can take different approach 00:21:36.659 --> 00:21:38.090 align:start position:0% so here you can take different approach either 00:21:38.090 --> 00:21:38.100 align:start position:0% either 00:21:38.100 --> 00:21:39.590 align:start position:0% either um<00:21:38.159> you<00:21:38.400> want<00:21:38.580> a<00:21:38.760> keynote<00:21:39.000> to<00:21:39.179> call<00:21:39.299> everything 00:21:39.590 --> 00:21:39.600 align:start position:0% um you want a keynote to call everything 00:21:39.600 --> 00:21:41.510 align:start position:0% um you want a keynote to call everything and<00:21:40.140> you<00:21:40.380> just<00:21:40.500> do<00:21:40.679> nothing<00:21:40.860> and<00:21:41.100> you<00:21:41.280> let<00:21:41.400> it 00:21:41.510 --> 00:21:41.520 align:start position:0% and you just do nothing and you let it 00:21:41.520 --> 00:21:43.430 align:start position:0% and you just do nothing and you let it now<00:21:41.820> when<00:21:42.120> uh<00:21:42.600> which<00:21:42.780> might<00:21:42.960> work<00:21:43.140> no<00:21:43.380> it 00:21:43.430 --> 00:21:43.440 align:start position:0% now when uh which might work no it 00:21:43.440 --> 00:21:46.909 align:start position:0% now when uh which might work no it depends<00:21:43.740> on<00:21:43.799> what<00:21:43.919> it<00:21:44.100> is<00:21:44.360> if<00:21:45.360> you<00:21:46.200> know<00:21:46.559> that 00:21:46.909 --> 00:21:46.919 align:start position:0% depends on what it is if you know that 00:21:46.919 --> 00:21:48.350 align:start position:0% depends on what it is if you know that some<00:21:47.100> functions<00:21:47.520> are<00:21:47.640> more<00:21:47.820> important<00:21:48.179> and 00:21:48.350 --> 00:21:48.360 align:start position:0% some functions are more important and 00:21:48.360 --> 00:21:51.049 align:start position:0% some functions are more important and you<00:21:48.539> want<00:21:48.659> to<00:21:48.780> Target<00:21:48.960> you<00:21:49.799> can<00:21:49.980> change<00:21:50.700> in<00:21:50.880> the 00:21:51.049 --> 00:21:51.059 align:start position:0% you want to Target you can change in the 00:21:51.059 --> 00:21:53.210 align:start position:0% you want to Target you can change in the configuration<00:21:51.799> configuration<00:21:52.799> file<00:21:53.039> of 00:21:53.210 --> 00:21:53.220 align:start position:0% configuration configuration file of 00:21:53.220 --> 00:21:55.430 align:start position:0% configuration configuration file of echina<00:21:53.580> and<00:21:53.880> tell<00:21:54.059> him<00:21:54.240> call<00:21:54.780> only<00:21:55.140> this 00:21:55.430 --> 00:21:55.440 align:start position:0% echina and tell him call only this 00:21:55.440 --> 00:21:57.950 align:start position:0% echina and tell him call only this function<00:21:55.740> or<00:21:56.039> don't<00:21:56.220> call<00:21:56.460> this<00:21:56.700> function<00:21:57.059> so 00:21:57.950 --> 00:21:57.960 align:start position:0% function or don't call this function so 00:21:57.960 --> 00:21:59.090 align:start position:0% function or don't call this function so it<00:21:58.080> depends<00:21:58.440> what<00:21:58.500> you<00:21:58.620> are<00:21:58.740> trying<00:21:58.860> to<00:21:58.980> look 00:21:59.090 --> 00:21:59.100 align:start position:0% it depends what you are trying to look 00:21:59.100 --> 00:22:01.190 align:start position:0% it depends what you are trying to look if<00:21:59.820> you<00:22:00.000> want<00:22:00.120> to<00:22:00.299> increase<00:22:00.480> your<00:22:00.840> confidence 00:22:01.190 --> 00:22:01.200 align:start position:0% if you want to increase your confidence 00:22:01.200 --> 00:22:04.070 align:start position:0% if you want to increase your confidence you<00:22:01.559> should<00:22:01.679> call<00:22:01.860> everything<00:22:02.600> if<00:22:03.600> you<00:22:03.900> think 00:22:04.070 --> 00:22:04.080 align:start position:0% you should call everything if you think 00:22:04.080 --> 00:22:05.450 align:start position:0% you should call everything if you think there<00:22:04.260> might<00:22:04.440> have<00:22:04.620> an<00:22:04.799> issue<00:22:05.039> in<00:22:05.159> a<00:22:05.280> specific 00:22:05.450 --> 00:22:05.460 align:start position:0% there might have an issue in a specific 00:22:05.460 --> 00:22:07.029 align:start position:0% there might have an issue in a specific function<00:22:05.760> and<00:22:06.000> you<00:22:06.120> want<00:22:06.299> to<00:22:06.419> focus<00:22:06.600> on<00:22:06.840> that 00:22:07.029 --> 00:22:07.039 align:start position:0% function and you want to focus on that 00:22:07.039 --> 00:22:11.270 align:start position:0% function and you want to focus on that you<00:22:08.039> can<00:22:08.159> you<00:22:08.280> can<00:22:08.400> Blacklist<00:22:08.760> on<00:22:09.000> white<00:22:09.179> list 00:22:11.270 --> 00:22:11.280 align:start position:0% you can you can Blacklist on white list 00:22:11.280 --> 00:22:16.490 align:start position:0% you can you can Blacklist on white list depending<00:22:12.059> order 00:22:16.490 --> 00:22:16.500 align:start position:0% 00:22:16.500 --> 00:22:19.190 align:start position:0% okay<00:22:17.100> so<00:22:17.340> the<00:22:17.520> question<00:22:17.820> is<00:22:18.360> can<00:22:18.780> you<00:22:18.960> define 00:22:19.190 --> 00:22:19.200 align:start position:0% okay so the question is can you define 00:22:19.200 --> 00:22:21.230 align:start position:0% okay so the question is can you define the<00:22:19.559> order<00:22:19.799> of<00:22:20.159> call 00:22:21.230 --> 00:22:21.240 align:start position:0% the order of call 00:22:21.240 --> 00:22:23.149 align:start position:0% the order of call you<00:22:21.720> can<00:22:21.840> Define<00:22:22.080> the<00:22:22.500> order<00:22:22.740> of<00:22:23.039> the 00:22:23.149 --> 00:22:23.159 align:start position:0% you can Define the order of the 00:22:23.159 --> 00:22:28.190 align:start position:0% you can Define the order of the initialization<00:22:23.780> but<00:22:24.780> not<00:22:24.960> after<00:22:25.140> that 00:22:28.190 --> 00:22:28.200 align:start position:0% 00:22:28.200 --> 00:22:30.529 align:start position:0% I<00:22:28.320> think<00:22:28.440> it<00:22:28.620> was<00:22:28.740> another<00:22:28.919> question 00:22:30.529 --> 00:22:30.539 align:start position:0% I think it was another question 00:22:30.539 --> 00:22:36.590 align:start position:0% I think it was another question no<00:22:30.900> okay 00:22:36.590 --> 00:22:36.600 align:start position:0% 00:22:36.600 --> 00:22:41.270 align:start position:0% okay 00:22:41.270 --> 00:22:41.280 align:start position:0% 00:22:41.280 --> 00:22:42.409 align:start position:0% okay 00:22:42.409 --> 00:22:42.419 align:start position:0% okay 00:22:42.419 --> 00:22:44.750 align:start position:0% okay so<00:22:43.020> the<00:22:43.200> question<00:22:43.500> is 00:22:44.750 --> 00:22:44.760 align:start position:0% so the question is 00:22:44.760 --> 00:22:46.250 align:start position:0% so the question is um can<00:22:45.120> you<00:22:45.299> have<00:22:45.480> like<00:22:45.659> a<00:22:45.840> better<00:22:46.020> log 00:22:46.250 --> 00:22:46.260 align:start position:0% um can you have like a better log 00:22:46.260 --> 00:22:48.470 align:start position:0% um can you have like a better log because<00:22:46.679> obviously<00:22:47.640> this<00:22:47.880> is<00:22:48.000> like<00:22:48.120> a<00:22:48.299> simple 00:22:48.470 --> 00:22:48.480 align:start position:0% because obviously this is like a simple 00:22:48.480 --> 00:22:51.049 align:start position:0% because obviously this is like a simple example<00:22:49.020> uh<00:22:49.919> and<00:22:50.100> when<00:22:50.220> you<00:22:50.340> do<00:22:50.460> want<00:22:50.640> them<00:22:50.880> you 00:22:51.049 --> 00:22:51.059 align:start position:0% example uh and when you do want them you 00:22:51.059 --> 00:22:52.730 align:start position:0% example uh and when you do want them you know<00:22:51.120> exploration<00:22:51.600> you<00:22:52.020> might<00:22:52.140> call<00:22:52.380> a<00:22:52.620> lot<00:22:52.679> of 00:22:52.730 --> 00:22:52.740 align:start position:0% know exploration you might call a lot of 00:22:52.740 --> 00:22:54.169 align:start position:0% know exploration you might call a lot of functions<00:22:53.100> that<00:22:53.280> are<00:22:53.400> not<00:22:53.580> necessary<00:22:53.940> for 00:22:54.169 --> 00:22:54.179 align:start position:0% functions that are not necessary for 00:22:54.179 --> 00:22:56.750 align:start position:0% functions that are not necessary for what<00:22:54.419> you<00:22:54.600> are<00:22:54.720> trying<00:22:54.840> to<00:22:55.020> to<00:22:55.320> call<00:22:55.919> right<00:22:56.159> and 00:22:56.750 --> 00:22:56.760 align:start position:0% what you are trying to to call right and 00:22:56.760 --> 00:22:58.370 align:start position:0% what you are trying to to call right and the<00:22:56.880> answer<00:22:57.000> is<00:22:57.299> yes 00:22:58.370 --> 00:22:58.380 align:start position:0% the answer is yes 00:22:58.380 --> 00:23:00.169 align:start position:0% the answer is yes um so<00:22:58.620> Echidna<00:22:59.280> does<00:22:59.520> what<00:22:59.820> we<00:23:00.000> call 00:23:00.169 --> 00:23:00.179 align:start position:0% um so Echidna does what we call 00:23:00.179 --> 00:23:03.770 align:start position:0% um so Echidna does what we call shrinking<00:23:00.900> where<00:23:01.740> once<00:23:02.220> it<00:23:02.460> found<00:23:02.700> a<00:23:03.240> way<00:23:03.539> to 00:23:03.770 --> 00:23:03.780 align:start position:0% shrinking where once it found a way to 00:23:03.780 --> 00:23:05.870 align:start position:0% shrinking where once it found a way to break<00:23:03.960> the<00:23:04.260> invariant<00:23:04.679> it's<00:23:05.159> going<00:23:05.340> to<00:23:05.460> try<00:23:05.760> to 00:23:05.870 --> 00:23:05.880 align:start position:0% break the invariant it's going to try to 00:23:05.880 --> 00:23:07.970 align:start position:0% break the invariant it's going to try to reduce<00:23:06.240> the<00:23:06.659> choice<00:23:07.020> so<00:23:07.620> it's<00:23:07.740> going<00:23:07.919> to 00:23:07.970 --> 00:23:07.980 align:start position:0% reduce the choice so it's going to 00:23:07.980 --> 00:23:09.890 align:start position:0% reduce the choice so it's going to continue<00:23:08.220> to<00:23:08.640> First<00:23:09.000> more<00:23:09.360> or<00:23:09.539> less<00:23:09.600> on<00:23:09.780> the 00:23:09.890 --> 00:23:09.900 align:start position:0% continue to First more or less on the 00:23:09.900 --> 00:23:12.830 align:start position:0% continue to First more or less on the seminal<00:23:10.260> iteration<00:23:11.179> uh<00:23:12.179> and<00:23:12.419> trying<00:23:12.659> to 00:23:12.830 --> 00:23:12.840 align:start position:0% seminal iteration uh and trying to 00:23:12.840 --> 00:23:15.470 align:start position:0% seminal iteration uh and trying to reduce<00:23:13.020> like<00:23:13.320> the<00:23:13.500> size<00:23:13.679> of<00:23:13.919> the<00:23:14.039> of<00:23:14.220> the<00:23:14.400> trace 00:23:15.470 --> 00:23:15.480 align:start position:0% reduce like the size of the of the trace 00:23:15.480 --> 00:23:26.420 align:start position:0% reduce like the size of the of the trace foreign 00:23:26.420 --> 00:23:26.430 align:start position:0% 00:23:26.430 --> 00:23:28.510 align:start position:0% [Music] 00:23:28.510 --> 00:23:28.520 align:start position:0% [Music] 00:23:28.520 --> 00:23:31.130 align:start position:0% [Music] Target<00:23:29.520> so<00:23:29.820> you're<00:23:30.000> going<00:23:30.179> to<00:23:30.299> try<00:23:30.659> to<00:23:30.840> have<00:23:31.020> an 00:23:31.130 --> 00:23:31.140 align:start position:0% Target so you're going to try to have an 00:23:31.140 --> 00:23:32.750 align:start position:0% Target so you're going to try to have an invariant 00:23:32.750 --> 00:23:32.760 align:start position:0% invariant 00:23:32.760 --> 00:23:34.730 align:start position:0% invariant um<00:23:32.820> on<00:23:33.240> the<00:23:33.419> same<00:23:33.600> token 00:23:34.730 --> 00:23:34.740 align:start position:0% um on the same token 00:23:34.740 --> 00:23:37.490 align:start position:0% um on the same token the<00:23:35.159> first<00:23:35.220> invariant<00:23:35.820> was<00:23:36.059> that 00:23:37.490 --> 00:23:37.500 align:start position:0% the first invariant was that 00:23:37.500 --> 00:23:39.169 align:start position:0% the first invariant was that no<00:23:37.860> user<00:23:38.220> should<00:23:38.460> have<00:23:38.580> a<00:23:38.640> balance<00:23:38.880> above 00:23:39.169 --> 00:23:39.179 align:start position:0% no user should have a balance above 00:23:39.179 --> 00:23:41.870 align:start position:0% no user should have a balance above total<00:23:39.480> Supply<00:23:39.720> here<00:23:40.679> as<00:23:40.980> we<00:23:41.220> kind<00:23:41.400> of<00:23:41.520> hinted 00:23:41.870 --> 00:23:41.880 align:start position:0% total Supply here as we kind of hinted 00:23:41.880 --> 00:23:43.970 align:start position:0% total Supply here as we kind of hinted before<00:23:42.120> now<00:23:42.600> this<00:23:42.840> is<00:23:42.900> a<00:23:43.020> possible<00:23:43.380> system<00:23:43.679> so 00:23:43.970 --> 00:23:43.980 align:start position:0% before now this is a possible system so 00:23:43.980 --> 00:23:45.950 align:start position:0% before now this is a possible system so it's<00:23:44.100> a<00:23:44.280> system<00:23:44.460> where<00:23:45.059> the<00:23:45.240> owner<00:23:45.539> can<00:23:45.780> pause 00:23:45.950 --> 00:23:45.960 align:start position:0% it's a system where the owner can pause 00:23:45.960 --> 00:23:48.529 align:start position:0% it's a system where the owner can pause or<00:23:46.260> unpause<00:23:46.500> the<00:23:46.860> system<00:23:47.039> and<00:23:47.880> what<00:23:48.120> we<00:23:48.360> want 00:23:48.529 --> 00:23:48.539 align:start position:0% or unpause the system and what we want 00:23:48.539 --> 00:23:50.390 align:start position:0% or unpause the system and what we want to<00:23:48.720> verify<00:23:49.260> the<00:23:49.559> environment<00:23:49.919> we<00:23:50.100> want<00:23:50.220> to 00:23:50.390 --> 00:23:50.400 align:start position:0% to verify the environment we want to 00:23:50.400 --> 00:23:51.770 align:start position:0% to verify the environment we want to have<00:23:50.580> is<00:23:50.880> that 00:23:51.770 --> 00:23:51.780 align:start position:0% have is that 00:23:51.780 --> 00:23:54.350 align:start position:0% have is that if<00:23:52.320> there<00:23:52.500> is<00:23:52.620> nowhere<00:23:52.919> now<00:23:53.580> and<00:23:54.059> the<00:23:54.240> system 00:23:54.350 --> 00:23:54.360 align:start position:0% if there is nowhere now and the system 00:23:54.360 --> 00:23:58.310 align:start position:0% if there is nowhere now and the system is<00:23:54.659> pause<00:23:55.039> can<00:23:56.039> someone<00:23:56.280> unpose<00:23:57.000> a<00:23:57.179> system<00:23:57.360> and 00:23:58.310 --> 00:23:58.320 align:start position:0% is pause can someone unpose a system and 00:23:58.320 --> 00:24:08.649 align:start position:0% is pause can someone unpose a system and this<00:23:58.559> is<00:23:58.620> what<00:23:58.799> we're<00:23:58.919> going<00:23:59.100> to<00:23:59.220> try 00:24:08.649 --> 00:24:08.659 align:start position:0% 00:24:08.659 --> 00:24:11.750 align:start position:0% and<00:24:09.659> yeah<00:24:09.840> let's<00:24:10.140> take<00:24:10.500> 10<00:24:11.039> minutes<00:24:11.280> for<00:24:11.580> this 00:24:11.750 --> 00:24:11.760 align:start position:0% and yeah let's take 10 minutes for this 00:24:11.760 --> 00:24:13.669 align:start position:0% and yeah let's take 10 minutes for this one 00:24:13.669 --> 00:24:13.679 align:start position:0% one 00:24:13.679 --> 00:24:16.070 align:start position:0% one I'm<00:24:13.980> going<00:24:14.220> to<00:24:14.340> show<00:24:14.820> the<00:24:15.360> solution<00:24:15.659> for<00:24:15.900> the 00:24:16.070 --> 00:24:16.080 align:start position:0% I'm going to show the solution for the 00:24:16.080 --> 00:24:18.890 align:start position:0% I'm going to show the solution for the second<00:24:16.200> one 00:24:18.890 --> 00:24:18.900 align:start position:0% 00:24:18.900 --> 00:24:22.010 align:start position:0% so<00:24:19.740> it's<00:24:20.580> the<00:24:20.820> same<00:24:21.000> Target<00:24:21.240> that<00:24:21.600> for<00:24:21.840> the 00:24:22.010 --> 00:24:22.020 align:start position:0% so it's the same Target that for the 00:24:22.020 --> 00:24:23.810 align:start position:0% so it's the same Target that for the first<00:24:22.200> exercise<00:24:22.440> but<00:24:22.980> here<00:24:23.220> we<00:24:23.400> are<00:24:23.520> going<00:24:23.700> to 00:24:23.810 --> 00:24:23.820 align:start position:0% first exercise but here we are going to 00:24:23.820 --> 00:24:26.090 align:start position:0% first exercise but here we are going to focus<00:24:24.179> on<00:24:24.840> the<00:24:25.260> contracts<00:24:25.740> that<00:24:25.919> were 00:24:26.090 --> 00:24:26.100 align:start position:0% focus on the contracts that were 00:24:26.100 --> 00:24:28.610 align:start position:0% focus on the contracts that were inherited<00:24:26.880> by<00:24:27.000> the<00:24:27.179> token<00:24:27.539> you<00:24:28.380> have<00:24:28.500> two 00:24:28.610 --> 00:24:28.620 align:start position:0% inherited by the token you have two 00:24:28.620 --> 00:24:30.110 align:start position:0% inherited by the token you have two token<00:24:29.039> now<00:24:29.220> you<00:24:29.340> have<00:24:29.460> two<00:24:29.520> contracts<00:24:29.940> right 00:24:30.110 --> 00:24:30.120 align:start position:0% token now you have two contracts right 00:24:30.120 --> 00:24:32.690 align:start position:0% token now you have two contracts right ownership<00:24:30.780> and<00:24:31.320> possible<00:24:31.740> and<00:24:32.159> here<00:24:32.400> you<00:24:32.580> have 00:24:32.690 --> 00:24:32.700 align:start position:0% ownership and possible and here you have 00:24:32.700 --> 00:24:35.930 align:start position:0% ownership and possible and here you have a<00:24:32.880> system<00:24:33.000> where<00:24:33.900> your<00:24:34.140> owner<00:24:34.799> and<00:24:35.580> you<00:24:35.760> can 00:24:35.930 --> 00:24:35.940 align:start position:0% a system where your owner and you can 00:24:35.940 --> 00:24:41.110 align:start position:0% a system where your owner and you can pause<00:24:36.240> or<00:24:36.720> resumes<00:24:37.320> as<00:24:37.500> a<00:24:37.740> contract 00:24:41.110 --> 00:24:41.120 align:start position:0% 00:24:41.120 --> 00:24:44.450 align:start position:0% and<00:24:42.120> what<00:24:42.299> we<00:24:42.539> want<00:24:42.720> to<00:24:42.900> check<00:24:43.140> is<00:24:43.679> that<00:24:43.919> if<00:24:44.280> we 00:24:44.450 --> 00:24:44.460 align:start position:0% and what we want to check is that if we 00:24:44.460 --> 00:24:47.330 align:start position:0% and what we want to check is that if we drop<00:24:44.700> the<00:24:45.360> ownership<00:24:45.720> and<00:24:46.620> we<00:24:46.799> pause<00:24:47.039> the 00:24:47.330 --> 00:24:47.340 align:start position:0% drop the ownership and we pause the 00:24:47.340 --> 00:24:47.990 align:start position:0% drop the ownership and we pause the system 00:24:47.990 --> 00:24:48.000 align:start position:0% system 00:24:48.000 --> 00:24:50.810 align:start position:0% system is<00:24:48.539> it<00:24:48.659> possible<00:24:49.020> to<00:24:49.260> unpause<00:24:49.440> it<00:24:49.860> so<00:24:50.460> here<00:24:50.640> we 00:24:50.810 --> 00:24:50.820 align:start position:0% is it possible to unpause it so here we 00:24:50.820 --> 00:24:52.850 align:start position:0% is it possible to unpause it so here we have<00:24:50.940> a<00:24:51.120> bit<00:24:51.240> of<00:24:51.480> initialization<00:24:52.140> to<00:24:52.500> do<00:24:52.620> what 00:24:52.850 --> 00:24:52.860 align:start position:0% have a bit of initialization to do what 00:24:52.860 --> 00:24:54.590 align:start position:0% have a bit of initialization to do what because<00:24:53.100> we<00:24:53.340> want<00:24:53.460> to<00:24:53.580> drop<00:24:53.880> the<00:24:54.299> ownership 00:24:54.590 --> 00:24:54.600 align:start position:0% because we want to drop the ownership 00:24:54.600 --> 00:24:57.049 align:start position:0% because we want to drop the ownership and<00:24:54.900> we<00:24:55.020> want<00:24:55.140> to<00:24:55.260> put<00:24:55.440> the<00:24:55.620> system<00:24:55.880> we<00:24:56.880> are 00:24:57.049 --> 00:24:57.059 align:start position:0% and we want to put the system we are 00:24:57.059 --> 00:24:59.149 align:start position:0% and we want to put the system we are doing<00:24:57.179> this<00:24:57.539> in<00:24:57.840> the<00:24:58.020> Constructor<00:24:58.500> so<00:24:58.860> we<00:24:59.039> are 00:24:59.149 --> 00:24:59.159 align:start position:0% doing this in the Constructor so we are 00:24:59.159 --> 00:25:01.789 align:start position:0% doing this in the Constructor so we are calling<00:24:59.400> pause<00:24:59.580> and<00:24:59.940> oh<00:25:00.120> no<00:25:00.360> from<00:25:01.140> now<00:25:01.320> on<00:25:01.500> the 00:25:01.789 --> 00:25:01.799 align:start position:0% calling pause and oh no from now on the 00:25:01.799 --> 00:25:03.950 align:start position:0% calling pause and oh no from now on the system<00:25:02.039> as<00:25:02.340> a<00:25:02.520> contract<00:25:02.760> is<00:25:02.880> deployed<00:25:03.419> it's 00:25:03.950 --> 00:25:03.960 align:start position:0% system as a contract is deployed it's 00:25:03.960 --> 00:25:07.250 align:start position:0% system as a contract is deployed it's pause<00:25:04.260> there<00:25:04.799> is<00:25:04.919> no<00:25:05.039> no 00:25:07.250 --> 00:25:07.260 align:start position:0% 00:25:07.260 --> 00:25:10.549 align:start position:0% the<00:25:07.740> invariant<00:25:08.220> is<00:25:08.520> then<00:25:08.820> just<00:25:09.480> if<00:25:10.320> the 00:25:10.549 --> 00:25:10.559 align:start position:0% the invariant is then just if the 00:25:10.559 --> 00:25:12.049 align:start position:0% the invariant is then just if the variable<00:25:10.919> that<00:25:11.220> you<00:25:11.400> know<00:25:11.520> tracks<00:25:11.880> the 00:25:12.049 --> 00:25:12.059 align:start position:0% variable that you know tracks the 00:25:12.059 --> 00:25:15.890 align:start position:0% variable that you know tracks the possible<00:25:12.960> state<00:25:13.500> of<00:25:13.679> the<00:25:13.860> system<00:25:14.039> is<00:25:14.460> true<00:25:14.900> and 00:25:15.890 --> 00:25:15.900 align:start position:0% possible state of the system is true and 00:25:15.900 --> 00:25:18.350 align:start position:0% possible state of the system is true and this<00:25:16.320> should<00:25:16.559> hard<00:25:16.860> work<00:25:17.159> you<00:25:17.640> pause<00:25:17.820> no 00:25:18.350 --> 00:25:18.360 align:start position:0% this should hard work you pause no 00:25:18.360 --> 00:25:23.049 align:start position:0% this should hard work you pause no ownership<00:25:18.740> it<00:25:19.740> should<00:25:19.860> be<00:25:19.980> always<00:25:20.100> post 00:25:23.049 --> 00:25:23.059 align:start position:0% 00:25:23.059 --> 00:25:25.909 align:start position:0% and<00:25:24.059> I<00:25:24.240> cannot<00:25:24.659> tells<00:25:25.080> us<00:25:25.140> that<00:25:25.440> it<00:25:25.740> actually 00:25:25.909 --> 00:25:25.919 align:start position:0% and I cannot tells us that it actually 00:25:25.919 --> 00:25:29.690 align:start position:0% and I cannot tells us that it actually failed<00:25:26.460> and<00:25:26.820> the<00:25:27.000> reason<00:25:27.120> for<00:25:27.480> that<00:25:27.720> so<00:25:28.700> this 00:25:29.690 --> 00:25:29.700 align:start position:0% failed and the reason for that so this 00:25:29.700 --> 00:25:32.210 align:start position:0% failed and the reason for that so this is<00:25:29.880> kind<00:25:30.179> of<00:25:30.240> like<00:25:30.419> an<00:25:30.720> old<00:25:31.020> bug<00:25:31.740> that<00:25:32.039> were 00:25:32.210 --> 00:25:32.220 align:start position:0% is kind of like an old bug that were 00:25:32.220 --> 00:25:33.649 align:start position:0% is kind of like an old bug that were really<00:25:32.460> frequent<00:25:32.940> and<00:25:33.120> common<00:25:33.240> in<00:25:33.480> old 00:25:33.649 --> 00:25:33.659 align:start position:0% really frequent and common in old 00:25:33.659 --> 00:25:34.909 align:start position:0% really frequent and common in old version<00:25:33.779> of<00:25:34.020> solidity 00:25:34.909 --> 00:25:34.919 align:start position:0% version of solidity 00:25:34.919 --> 00:25:37.549 align:start position:0% version of solidity there<00:25:35.460> was<00:25:35.580> no<00:25:35.820> constrictor<00:25:36.419> keywords<00:25:37.080> and 00:25:37.549 --> 00:25:37.559 align:start position:0% there was no constrictor keywords and 00:25:37.559 --> 00:25:39.049 align:start position:0% there was no constrictor keywords and where<00:25:37.919> you<00:25:38.159> were<00:25:38.220> doing<00:25:38.460> the<00:25:38.700> Constructor 00:25:39.049 --> 00:25:39.059 align:start position:0% where you were doing the Constructor 00:25:39.059 --> 00:25:41.269 align:start position:0% where you were doing the Constructor that<00:25:39.539> you<00:25:39.659> needed<00:25:39.960> to<00:25:40.200> have<00:25:40.380> the<00:25:40.919> function 00:25:41.269 --> 00:25:41.279 align:start position:0% that you needed to have the function 00:25:41.279 --> 00:25:43.010 align:start position:0% that you needed to have the function name<00:25:41.520> which<00:25:41.820> was<00:25:42.000> a<00:25:42.179> match<00:25:42.360> with<00:25:42.600> the<00:25:42.720> contract 00:25:43.010 --> 00:25:43.020 align:start position:0% name which was a match with the contract 00:25:43.020 --> 00:25:44.930 align:start position:0% name which was a match with the contract name<00:25:43.260> and<00:25:43.860> here<00:25:44.039> you<00:25:44.279> have<00:25:44.460> the<00:25:44.580> contract 00:25:44.930 --> 00:25:44.940 align:start position:0% name and here you have the contract 00:25:44.940 --> 00:25:47.870 align:start position:0% name and here you have the contract ownership<00:25:45.419> and<00:25:45.779> a<00:25:45.960> function<00:25:46.200> owner<00:25:46.880> and 00:25:47.870 --> 00:25:47.880 align:start position:0% ownership and a function owner and 00:25:47.880 --> 00:25:49.490 align:start position:0% ownership and a function owner and because<00:25:48.120> of<00:25:48.360> that<00:25:48.480> the<00:25:48.720> functional<00:25:49.080> is<00:25:49.440> a 00:25:49.490 --> 00:25:49.500 align:start position:0% because of that the functional is a 00:25:49.500 --> 00:25:51.529 align:start position:0% because of that the functional is a public<00:25:49.620> function<00:25:50.100> and<00:25:50.520> anyone<00:25:51.000> can<00:25:51.299> call<00:25:51.419> it 00:25:51.529 --> 00:25:51.539 align:start position:0% public function and anyone can call it 00:25:51.539 --> 00:25:54.169 align:start position:0% public function and anyone can call it and<00:25:51.720> become<00:25:52.020> the<00:25:52.200> owner<00:25:52.799> this<00:25:53.520> does<00:25:53.760> not<00:25:53.940> work 00:25:54.169 --> 00:25:54.179 align:start position:0% and become the owner this does not work 00:25:54.179 --> 00:25:55.549 align:start position:0% and become the owner this does not work anymore<00:25:54.539> with<00:25:54.900> more<00:25:55.140> you<00:25:55.320> know<00:25:55.380> modern 00:25:55.549 --> 00:25:55.559 align:start position:0% anymore with more you know modern 00:25:55.559 --> 00:25:57.950 align:start position:0% anymore with more you know modern version<00:25:55.860> of<00:25:56.100> solidity<00:25:56.520> but<00:25:57.240> the<00:25:57.539> type<00:25:57.659> of<00:25:57.720> bug 00:25:57.950 --> 00:25:57.960 align:start position:0% version of solidity but the type of bug 00:25:57.960 --> 00:26:01.909 align:start position:0% version of solidity but the type of bug that<00:25:58.260> we<00:25:58.500> are<00:25:58.740> finding<00:25:59.640> a<00:26:00.360> bit<00:26:00.600> more<00:26:00.779> a<00:26:01.380> bit<00:26:01.740> too 00:26:01.909 --> 00:26:01.919 align:start position:0% that we are finding a bit more a bit too 00:26:01.919 --> 00:26:04.130 align:start position:0% that we are finding a bit more a bit too much<00:26:02.100> in<00:26:02.700> the<00:26:02.760> past 00:26:04.130 --> 00:26:04.140 align:start position:0% much in the past 00:26:04.140 --> 00:26:05.930 align:start position:0% much in the past something<00:26:04.500> which<00:26:04.740> is<00:26:04.860> interesting<00:26:05.340> again<00:26:05.520> is 00:26:05.930 --> 00:26:05.940 align:start position:0% something which is interesting again is 00:26:05.940 --> 00:26:07.850 align:start position:0% something which is interesting again is that<00:26:06.179> you<00:26:06.360> know<00:26:06.480> we<00:26:06.900> did<00:26:07.020> not<00:26:07.200> look<00:26:07.500> at<00:26:07.740> the 00:26:07.850 --> 00:26:07.860 align:start position:0% that you know we did not look at the 00:26:07.860 --> 00:26:09.710 align:start position:0% that you know we did not look at the ownership<00:26:08.159> contract<00:26:08.640> we<00:26:08.940> did<00:26:09.179> not<00:26:09.299> look<00:26:09.539> like 00:26:09.710 --> 00:26:09.720 align:start position:0% ownership contract we did not look like 00:26:09.720 --> 00:26:11.870 align:start position:0% ownership contract we did not look like at<00:26:09.960> the<00:26:10.200> implementation<00:26:10.919> itself<00:26:11.400> we<00:26:11.640> just 00:26:11.870 --> 00:26:11.880 align:start position:0% at the implementation itself we just 00:26:11.880 --> 00:26:14.510 align:start position:0% at the implementation itself we just Define<00:26:12.059> an<00:26:12.419> invariant<00:26:12.960> and<00:26:13.799> without<00:26:14.039> the<00:26:14.340> one 00:26:14.510 --> 00:26:14.520 align:start position:0% Define an invariant and without the one 00:26:14.520 --> 00:26:16.490 align:start position:0% Define an invariant and without the one of<00:26:14.700> the<00:26:14.880> further<00:26:15.419> one<00:26:15.659> and<00:26:15.900> you<00:26:16.020> found<00:26:16.200> the 00:26:16.490 --> 00:26:16.500 align:start position:0% of the further one and you found the 00:26:16.500 --> 00:26:18.470 align:start position:0% of the further one and you found the environment<00:26:17.100> for<00:26:17.220> us 00:26:18.470 --> 00:26:18.480 align:start position:0% environment for us 00:26:18.480 --> 00:26:21.590 align:start position:0% environment for us so<00:26:19.200> now<00:26:19.500> bring<00:26:19.919> the<00:26:20.159> question<00:26:20.460> on<00:26:21.059> how<00:26:21.419> to 00:26:21.590 --> 00:26:21.600 align:start position:0% so now bring the question on how to 00:26:21.600 --> 00:26:23.269 align:start position:0% so now bring the question on how to define<00:26:21.779> it<00:26:22.140> okay 00:26:23.269 --> 00:26:23.279 align:start position:0% define it okay 00:26:23.279 --> 00:26:26.930 align:start position:0% define it okay foreign 00:26:26.930 --> 00:26:26.940 align:start position:0% 00:26:26.940 --> 00:26:28.390 align:start position:0% okay 00:26:28.390 --> 00:26:28.400 align:start position:0% okay 00:26:28.400 --> 00:26:32.330 align:start position:0% okay so<00:26:29.400> the<00:26:29.580> question<00:26:29.880> is<00:26:30.360> is<00:26:30.840> defining<00:26:31.740> invariant 00:26:32.330 --> 00:26:32.340 align:start position:0% so the question is is defining invariant 00:26:32.340 --> 00:26:35.750 align:start position:0% so the question is is defining invariant part<00:26:32.580> of<00:26:32.820> the<00:26:33.120> auditor<00:26:34.080> you<00:26:34.320> know<00:26:34.440> work<00:26:34.679> uh<00:26:35.520> yes 00:26:35.750 --> 00:26:35.760 align:start position:0% part of the auditor you know work uh yes 00:26:35.760 --> 00:26:37.610 align:start position:0% part of the auditor you know work uh yes like<00:26:36.120> we<00:26:36.360> are<00:26:36.539> using<00:26:36.720> a<00:26:36.840> Kinder<00:26:37.140> in<00:26:37.260> our<00:26:37.320> audit 00:26:37.610 --> 00:26:37.620 align:start position:0% like we are using a Kinder in our audit 00:26:37.620 --> 00:26:38.870 align:start position:0% like we are using a Kinder in our audit and<00:26:37.740> during<00:26:37.919> our<00:26:38.100> audit<00:26:38.340> we<00:26:38.520> are<00:26:38.640> going<00:26:38.760> to 00:26:38.870 --> 00:26:38.880 align:start position:0% and during our audit we are going to 00:26:38.880 --> 00:26:41.210 align:start position:0% and during our audit we are going to Define<00:26:39.059> invariant<00:26:40.080> and<00:26:40.679> something<00:26:40.799> we<00:26:41.100> are 00:26:41.210 --> 00:26:41.220 align:start position:0% Define invariant and something we are 00:26:41.220 --> 00:26:42.590 align:start position:0% Define invariant and something we are going<00:26:41.279> to<00:26:41.400> do<00:26:41.520> that<00:26:41.700> we<00:26:41.880> are<00:26:42.000> going<00:26:42.120> to<00:26:42.240> discuss 00:26:42.590 --> 00:26:42.600 align:start position:0% going to do that we are going to discuss 00:26:42.600 --> 00:26:44.269 align:start position:0% going to do that we are going to discuss with<00:26:42.960> the<00:26:43.140> developer<00:26:43.559> because<00:26:43.919> the 00:26:44.269 --> 00:26:44.279 align:start position:0% with the developer because the 00:26:44.279 --> 00:26:46.370 align:start position:0% with the developer because the developers<00:26:44.940> know<00:26:45.240> you<00:26:45.539> know<00:26:45.659> better<00:26:45.840> than<00:26:46.140> us 00:26:46.370 --> 00:26:46.380 align:start position:0% developers know you know better than us 00:26:46.380 --> 00:26:48.350 align:start position:0% developers know you know better than us what<00:26:46.679> the<00:26:46.860> system<00:26:47.039> is<00:26:47.279> supposed<00:26:47.460> to<00:26:47.700> do<00:26:47.820> so<00:26:48.240> we 00:26:48.350 --> 00:26:48.360 align:start position:0% what the system is supposed to do so we 00:26:48.360 --> 00:26:49.549 align:start position:0% what the system is supposed to do so we are<00:26:48.480> going<00:26:48.600> to<00:26:48.720> have<00:26:48.840> this<00:26:49.020> collaboration 00:26:49.549 --> 00:26:49.559 align:start position:0% are going to have this collaboration 00:26:49.559 --> 00:26:52.250 align:start position:0% are going to have this collaboration with<00:26:50.520> them<00:26:50.640> to<00:26:50.820> understand<00:26:50.940> what<00:26:51.299> the<00:26:51.480> system 00:26:52.250 --> 00:26:52.260 align:start position:0% with them to understand what the system 00:26:52.260 --> 00:26:53.990 align:start position:0% with them to understand what the system is<00:26:52.440> supposed<00:26:52.620> to<00:26:52.799> do<00:26:52.980> and<00:26:53.400> to<00:26:53.520> Define<00:26:53.700> this 00:26:53.990 --> 00:26:54.000 align:start position:0% is supposed to do and to Define this 00:26:54.000 --> 00:26:55.190 align:start position:0% is supposed to do and to Define this variants 00:26:55.190 --> 00:26:55.200 align:start position:0% variants 00:26:55.200 --> 00:26:56.950 align:start position:0% variants foreign 00:26:56.950 --> 00:26:56.960 align:start position:0% foreign 00:26:56.960 --> 00:27:00.049 align:start position:0% foreign how<00:26:57.960> to<00:26:58.080> define<00:26:58.320> invariance 00:27:00.049 --> 00:27:00.059 align:start position:0% how to define invariance 00:27:00.059 --> 00:27:02.149 align:start position:0% how to define invariance because<00:27:00.480> you<00:27:00.779> know<00:27:00.900> like 00:27:02.149 --> 00:27:02.159 align:start position:0% because you know like 00:27:02.159 --> 00:27:04.370 align:start position:0% because you know like if<00:27:02.400> you<00:27:02.580> have<00:27:02.760> bad<00:27:02.940> invariance<00:27:03.659> it<00:27:04.200> doesn't 00:27:04.370 --> 00:27:04.380 align:start position:0% if you have bad invariance it doesn't 00:27:04.380 --> 00:27:06.110 align:start position:0% if you have bad invariance it doesn't matter<00:27:04.860> what<00:27:05.279> you<00:27:05.400> are<00:27:05.520> doing<00:27:05.640> you<00:27:05.880> know<00:27:06.000> if 00:27:06.110 --> 00:27:06.120 align:start position:0% matter what you are doing you know if 00:27:06.120 --> 00:27:07.610 align:start position:0% matter what you are doing you know if you<00:27:06.179> are<00:27:06.299> using<00:27:06.539> further<00:27:06.840> if<00:27:07.140> you<00:27:07.260> are<00:27:07.380> using 00:27:07.610 --> 00:27:07.620 align:start position:0% you are using further if you are using 00:27:07.620 --> 00:27:09.289 align:start position:0% you are using further if you are using like<00:27:07.740> formal<00:27:08.100> method<00:27:08.340> if<00:27:08.580> your<00:27:08.700> invariant<00:27:09.120> are 00:27:09.289 --> 00:27:09.299 align:start position:0% like formal method if your invariant are 00:27:09.299 --> 00:27:10.970 align:start position:0% like formal method if your invariant are not<00:27:09.419> good<00:27:09.600> you're<00:27:10.140> just<00:27:10.320> going<00:27:10.500> to<00:27:10.559> check<00:27:10.740> for 00:27:10.970 --> 00:27:10.980 align:start position:0% not good you're just going to check for 00:27:10.980 --> 00:27:13.970 align:start position:0% not good you're just going to check for some<00:27:11.159> things<00:27:11.340> that<00:27:11.520> you<00:27:11.640> know<00:27:11.760> doesn't<00:27:12.059> matter 00:27:13.970 --> 00:27:13.980 align:start position:0% some things that you know doesn't matter 00:27:13.980 --> 00:27:17.210 align:start position:0% some things that you know doesn't matter the<00:27:14.340> best<00:27:14.700> approach<00:27:15.360> to<00:27:15.600> writing<00:27:16.080> variants 00:27:17.210 --> 00:27:17.220 align:start position:0% the best approach to writing variants 00:27:17.220 --> 00:27:20.090 align:start position:0% the best approach to writing variants is<00:27:17.760> not<00:27:18.059> to<00:27:18.299> start<00:27:18.539> with<00:27:18.960> a<00:27:19.200> tool<00:27:19.559> it's<00:27:19.679> not<00:27:19.919> to 00:27:20.090 --> 00:27:20.100 align:start position:0% is not to start with a tool it's not to 00:27:20.100 --> 00:27:21.350 align:start position:0% is not to start with a tool it's not to start<00:27:20.279> with<00:27:20.580> you<00:27:20.820> know<00:27:20.940> writing<00:27:21.240> down 00:27:21.350 --> 00:27:21.360 align:start position:0% start with you know writing down 00:27:21.360 --> 00:27:23.390 align:start position:0% start with you know writing down solidity<00:27:21.840> invariant<00:27:22.320> is<00:27:22.860> to<00:27:23.039> start<00:27:23.159> with 00:27:23.390 --> 00:27:23.400 align:start position:0% solidity invariant is to start with 00:27:23.400 --> 00:27:24.169 align:start position:0% solidity invariant is to start with English 00:27:24.169 --> 00:27:24.179 align:start position:0% English 00:27:24.179 --> 00:27:26.269 align:start position:0% English open<00:27:24.779> a<00:27:25.080> file<00:27:25.260> and<00:27:25.440> markdown<00:27:25.860> file<00:27:26.100> or 00:27:26.269 --> 00:27:26.279 align:start position:0% open a file and markdown file or 00:27:26.279 --> 00:27:28.789 align:start position:0% open a file and markdown file or whatever<00:27:26.400> I<00:27:26.760> know<00:27:26.940> a<00:27:27.299> format<00:27:27.659> you<00:27:27.840> like<00:27:28.020> and 00:27:28.789 --> 00:27:28.799 align:start position:0% whatever I know a format you like and 00:27:28.799 --> 00:27:30.649 align:start position:0% whatever I know a format you like and write<00:27:29.159> in<00:27:29.340> English<00:27:29.580> what<00:27:29.940> the<00:27:30.179> system<00:27:30.360> is 00:27:30.649 --> 00:27:30.659 align:start position:0% write in English what the system is 00:27:30.659 --> 00:27:33.409 align:start position:0% write in English what the system is supposed<00:27:30.840> to<00:27:31.080> do<00:27:31.740> start<00:27:32.400> simple<00:27:32.760> start<00:27:33.179> with 00:27:33.409 --> 00:27:33.419 align:start position:0% supposed to do start simple start with 00:27:33.419 --> 00:27:35.090 align:start position:0% supposed to do start simple start with invariants<00:27:33.960> that<00:27:34.200> you<00:27:34.320> know<00:27:34.559> you<00:27:34.799> know<00:27:34.919> are 00:27:35.090 --> 00:27:35.100 align:start position:0% invariants that you know you know are 00:27:35.100 --> 00:27:36.529 align:start position:0% invariants that you know you know are true<00:27:35.340> start<00:27:35.580> with<00:27:35.820> things<00:27:36.059> that<00:27:36.240> are<00:27:36.360> not 00:27:36.529 --> 00:27:36.539 align:start position:0% true start with things that are not 00:27:36.539 --> 00:27:37.490 align:start position:0% true start with things that are not working 00:27:37.490 --> 00:27:37.500 align:start position:0% working 00:27:37.500 --> 00:27:41.870 align:start position:0% working once<00:27:38.220> you<00:27:38.340> have<00:27:38.659> 5<00:27:39.659> or<00:27:39.960> 10<00:27:40.140> simple<00:27:40.500> invariants 00:27:41.870 --> 00:27:41.880 align:start position:0% once you have 5 or 10 simple invariants 00:27:41.880 --> 00:27:43.909 align:start position:0% once you have 5 or 10 simple invariants buy<00:27:42.240> them<00:27:42.480> in<00:27:42.600> solidity<00:27:43.020> and<00:27:43.440> when<00:27:43.740> the 00:27:43.909 --> 00:27:43.919 align:start position:0% buy them in solidity and when the 00:27:43.919 --> 00:27:45.350 align:start position:0% buy them in solidity and when the further<00:27:44.100> on<00:27:44.340> top<00:27:44.460> of<00:27:44.640> them 00:27:45.350 --> 00:27:45.360 align:start position:0% further on top of them 00:27:45.360 --> 00:27:48.409 align:start position:0% further on top of them if<00:27:45.779> the<00:27:45.960> invariant<00:27:46.919> are<00:27:47.520> all<00:27:47.700> holding<00:27:48.179> then 00:27:48.409 --> 00:27:48.419 align:start position:0% if the invariant are all holding then 00:27:48.419 --> 00:27:49.909 align:start position:0% if the invariant are all holding then you<00:27:48.600> can<00:27:48.659> go<00:27:48.840> back<00:27:49.020> to<00:27:49.200> thinking<00:27:49.620> about<00:27:49.740> the 00:27:49.909 --> 00:27:49.919 align:start position:0% you can go back to thinking about the 00:27:49.919 --> 00:27:52.730 align:start position:0% you can go back to thinking about the event<00:27:50.100> of<00:27:50.340> the<00:27:50.520> system<00:27:50.700> and<00:27:51.600> you<00:27:51.840> know<00:27:51.900> go<00:27:52.440> more 00:27:52.730 --> 00:27:52.740 align:start position:0% event of the system and you know go more 00:27:52.740 --> 00:27:54.409 align:start position:0% event of the system and you know go more deeper<00:27:53.460> into<00:27:53.640> into<00:27:53.880> the<00:27:54.120> environment 00:27:54.409 --> 00:27:54.419 align:start position:0% deeper into into the environment 00:27:54.419 --> 00:27:56.750 align:start position:0% deeper into into the environment themselves<00:27:54.840> if<00:27:55.320> something<00:27:55.559> is<00:27:55.799> broken<00:27:56.039> then 00:27:56.750 --> 00:27:56.760 align:start position:0% themselves if something is broken then 00:27:56.760 --> 00:27:59.570 align:start position:0% themselves if something is broken then look<00:27:57.120> if<00:27:57.600> the<00:27:57.900> invariant<00:27:58.380> is<00:27:58.559> incorrect<00:27:59.100> or<00:27:59.340> if 00:27:59.570 --> 00:27:59.580 align:start position:0% look if the invariant is incorrect or if 00:27:59.580 --> 00:28:01.130 align:start position:0% look if the invariant is incorrect or if there<00:27:59.700> is<00:27:59.880> an<00:27:59.940> actual<00:28:00.240> bug 00:28:01.130 --> 00:28:01.140 align:start position:0% there is an actual bug 00:28:01.140 --> 00:28:03.830 align:start position:0% there is an actual bug and<00:28:01.860> iterates<00:28:02.460> go<00:28:02.820> over 00:28:03.830 --> 00:28:03.840 align:start position:0% and iterates go over 00:28:03.840 --> 00:28:05.750 align:start position:0% and iterates go over um<00:28:03.900> yeah<00:28:04.200> in<00:28:04.500> in<00:28:04.679> our<00:28:04.919> experience<00:28:05.279> when<00:28:05.580> we 00:28:05.750 --> 00:28:05.760 align:start position:0% um yeah in in our experience when we 00:28:05.760 --> 00:28:09.350 align:start position:0% um yeah in in our experience when we work<00:28:06.000> with<00:28:06.299> uh<00:28:06.840> with<00:28:07.799> um<00:28:07.799> with<00:28:08.340> clients<00:28:08.760> when 00:28:09.350 --> 00:28:09.360 align:start position:0% work with uh with um with clients when 00:28:09.360 --> 00:28:11.529 align:start position:0% work with uh with um with clients when we<00:28:09.539> ask<00:28:09.659> them<00:28:09.900> to<00:28:10.140> do<00:28:10.260> step<00:28:10.559> one 00:28:11.529 --> 00:28:11.539 align:start position:0% we ask them to do step one 00:28:11.539 --> 00:28:14.409 align:start position:0% we ask them to do step one undefined<00:28:12.539> invariants<00:28:13.080> they<00:28:13.860> are<00:28:14.039> actually 00:28:14.409 --> 00:28:14.419 align:start position:0% undefined invariants they are actually 00:28:14.419 --> 00:28:18.649 align:start position:0% undefined invariants they are actually uh<00:28:15.419> they<00:28:15.659> they<00:28:15.779> realize<00:28:16.200> about<00:28:16.460> bugs<00:28:17.460> so<00:28:18.120> it<00:28:18.360> is 00:28:18.649 --> 00:28:18.659 align:start position:0% uh they they realize about bugs so it is 00:28:18.659 --> 00:28:20.630 align:start position:0% uh they they realize about bugs so it is already<00:28:18.900> a<00:28:19.380> good<00:28:19.500> a<00:28:19.740> very<00:28:19.919> good<00:28:20.159> thing<00:28:20.400> to 00:28:20.630 --> 00:28:20.640 align:start position:0% already a good a very good thing to 00:28:20.640 --> 00:28:22.430 align:start position:0% already a good a very good thing to start<00:28:20.880> thinking<00:28:21.240> into<00:28:21.419> that<00:28:21.659> even<00:28:22.080> if<00:28:22.320> you 00:28:22.430 --> 00:28:22.440 align:start position:0% start thinking into that even if you 00:28:22.440 --> 00:28:46.090 align:start position:0% start thinking into that even if you don't<00:28:22.559> if<00:28:22.799> you're<00:28:22.980> not<00:28:23.100> testing<00:28:23.460> yeah 00:28:46.090 --> 00:28:46.100 align:start position:0% 00:28:46.100 --> 00:28:49.190 align:start position:0% okay<00:28:47.100> okay<00:28:47.299> so<00:28:48.299> if<00:28:48.480> I<00:28:48.659> understand<00:28:48.720> correctly 00:28:49.190 --> 00:28:49.200 align:start position:0% okay okay so if I understand correctly 00:28:49.200 --> 00:28:51.289 align:start position:0% okay okay so if I understand correctly the<00:28:49.380> question<00:28:49.620> is<00:28:49.860> that<00:28:49.980> can<00:28:50.279> we<00:28:50.460> connect<00:28:50.700> this 00:28:51.289 --> 00:28:51.299 align:start position:0% the question is that can we connect this 00:28:51.299 --> 00:29:00.350 align:start position:0% the question is that can we connect this to<00:28:51.539> mainnet<00:28:52.380> okay 00:29:00.350 --> 00:29:00.360 align:start position:0% 00:29:00.360 --> 00:29:02.570 align:start position:0% okay<00:29:01.020> how<00:29:01.320> to<00:29:01.440> use<00:29:01.559> it<00:29:01.740> with<00:29:01.860> other<00:29:02.100> contract 00:29:02.570 --> 00:29:02.580 align:start position:0% okay how to use it with other contract 00:29:02.580 --> 00:29:04.010 align:start position:0% okay how to use it with other contract so<00:29:02.940> you<00:29:03.059> can<00:29:03.179> just<00:29:03.360> in<00:29:03.539> the<00:29:03.720> Constructor 00:29:04.010 --> 00:29:04.020 align:start position:0% so you can just in the Constructor 00:29:04.020 --> 00:29:07.070 align:start position:0% so you can just in the Constructor deploy<00:29:04.740> the<00:29:04.919> contract<00:29:05.419> uh<00:29:06.419> something<00:29:06.659> that<00:29:06.960> we 00:29:07.070 --> 00:29:07.080 align:start position:0% deploy the contract uh something that we 00:29:07.080 --> 00:29:08.510 align:start position:0% deploy the contract uh something that we are<00:29:07.260> not<00:29:07.320> going<00:29:07.440> to<00:29:07.559> cover<00:29:07.740> here<00:29:08.039> but<00:29:08.220> we<00:29:08.400> have 00:29:08.510 --> 00:29:08.520 align:start position:0% are not going to cover here but we have 00:29:08.520 --> 00:29:11.149 align:start position:0% are not going to cover here but we have a<00:29:08.640> tool<00:29:08.880> which<00:29:09.000> is<00:29:09.120> called<00:29:09.299> itino<00:29:10.039> which<00:29:11.039> is 00:29:11.149 --> 00:29:11.159 align:start position:0% a tool which is called itino which is 00:29:11.159 --> 00:29:13.490 align:start position:0% a tool which is called itino which is basically<00:29:11.520> going<00:29:11.880> to<00:29:12.360> take<00:29:12.840> your<00:29:13.020> unit<00:29:13.200> test 00:29:13.490 --> 00:29:13.500 align:start position:0% basically going to take your unit test 00:29:13.500 --> 00:29:16.370 align:start position:0% basically going to take your unit test take<00:29:13.799> like<00:29:14.100> your<00:29:14.340> suite<00:29:15.000> and<00:29:15.419> we<00:29:15.779> play<00:29:15.960> them<00:29:16.200> in 00:29:16.370 --> 00:29:16.380 align:start position:0% take like your suite and we play them in 00:29:16.380 --> 00:29:18.409 align:start position:0% take like your suite and we play them in Echidna<00:29:16.919> so<00:29:17.279> for<00:29:17.460> example<00:29:17.700> if<00:29:18.059> you<00:29:18.120> have<00:29:18.240> like 00:29:18.409 --> 00:29:18.419 align:start position:0% Echidna so for example if you have like 00:29:18.419 --> 00:29:20.149 align:start position:0% Echidna so for example if you have like a<00:29:18.539> complex<00:29:18.779> integration<00:29:19.320> with<00:29:19.679> like<00:29:19.919> you<00:29:20.100> know 00:29:20.149 --> 00:29:20.159 align:start position:0% a complex integration with like you know 00:29:20.159 --> 00:29:22.070 align:start position:0% a complex integration with like you know you<00:29:20.520> are<00:29:20.640> deploying<00:29:21.059> in<00:29:21.179> your<00:29:21.419> unit<00:29:21.539> test<00:29:21.779> 10 00:29:22.070 --> 00:29:22.080 align:start position:0% you are deploying in your unit test 10 00:29:22.080 --> 00:29:23.570 align:start position:0% you are deploying in your unit test 10 different<00:29:22.320> contracts<00:29:22.980> you<00:29:23.100> are<00:29:23.220> deploying 00:29:23.570 --> 00:29:23.580 align:start position:0% different contracts you are deploying 00:29:23.580 --> 00:29:25.430 align:start position:0% different contracts you are deploying like<00:29:23.700> a<00:29:23.940> knockoff<00:29:24.480> unit<00:29:24.600> swap<00:29:25.020> or<00:29:25.200> whatever 00:29:25.430 --> 00:29:25.440 align:start position:0% like a knockoff unit swap or whatever 00:29:25.440 --> 00:29:26.930 align:start position:0% like a knockoff unit swap or whatever you<00:29:25.679> know<00:29:25.740> you<00:29:25.980> need<00:29:26.100> and<00:29:26.460> you<00:29:26.640> can<00:29:26.700> replay 00:29:26.930 --> 00:29:26.940 align:start position:0% you know you need and you can replay 00:29:26.940 --> 00:29:28.190 align:start position:0% you know you need and you can replay this<00:29:27.360> in<00:29:27.480> the<00:29:27.600> keynote<00:29:27.840> so<00:29:28.020> that<00:29:28.140> everything 00:29:28.190 --> 00:29:28.200 align:start position:0% this in the keynote so that everything 00:29:28.200 --> 00:29:29.950 align:start position:0% this in the keynote so that everything is<00:29:28.440> going<00:29:28.799> to<00:29:28.860> be<00:29:28.980> set<00:29:29.159> up 00:29:29.950 --> 00:29:29.960 align:start position:0% is going to be set up 00:29:29.960 --> 00:29:33.350 align:start position:0% is going to be set up yes<00:29:30.960> yes<00:29:31.200> I<00:29:31.559> I<00:29:31.740> uh<00:29:32.159> I<00:29:32.460> think<00:29:32.580> there's<00:29:32.820> some<00:29:33.120> a 00:29:33.350 --> 00:29:33.360 align:start position:0% yes yes I I uh I think there's some a 00:29:33.360 --> 00:29:36.350 align:start position:0% yes yes I I uh I think there's some a little<00:29:33.659> bit<00:29:34.020> something<00:29:34.380> else<00:29:34.620> there<00:29:34.860> that<00:29:35.360> you 00:29:36.350 --> 00:29:36.360 align:start position:0% little bit something else there that you 00:29:36.360 --> 00:29:38.149 align:start position:0% little bit something else there that you want<00:29:36.600> to<00:29:36.779> what<00:29:37.140> if<00:29:37.320> you<00:29:37.500> want<00:29:37.620> to<00:29:37.740> Define<00:29:37.860> an 00:29:38.149 --> 00:29:38.159 align:start position:0% want to what if you want to Define an 00:29:38.159 --> 00:29:41.029 align:start position:0% want to what if you want to Define an invariant<00:29:38.700> on<00:29:39.120> a<00:29:39.240> uni<00:29:39.539> swap<00:29:39.779> contract<00:29:40.260> right 00:29:41.029 --> 00:29:41.039 align:start position:0% invariant on a uni swap contract right 00:29:41.039 --> 00:29:42.710 align:start position:0% invariant on a uni swap contract right that<00:29:41.399> you<00:29:41.580> that<00:29:41.820> you<00:29:42.000> are<00:29:42.120> using<00:29:42.360> that<00:29:42.539> your 00:29:42.710 --> 00:29:42.720 align:start position:0% that you that you are using that your 00:29:42.720 --> 00:29:45.830 align:start position:0% that you that you are using that your contract<00:29:43.080> is<00:29:43.260> is<00:29:43.799> is<00:29:43.919> using<00:29:44.760> so<00:29:45.179> you<00:29:45.419> will<00:29:45.600> need 00:29:45.830 --> 00:29:45.840 align:start position:0% contract is is is using so you will need 00:29:45.840 --> 00:29:50.029 align:start position:0% contract is is is using so you will need to<00:29:46.080> know<00:29:46.260> how<00:29:46.799> Unison<00:29:47.600> uh<00:29:48.600> Works<00:29:49.260> in<00:29:49.679> order<00:29:49.799> to 00:29:50.029 --> 00:29:50.039 align:start position:0% to know how Unison uh Works in order to 00:29:50.039 --> 00:29:51.950 align:start position:0% to know how Unison uh Works in order to put<00:29:50.399> it<00:29:50.520> in<00:29:50.700> your<00:29:50.820> environment<00:29:51.299> like<00:29:51.480> if<00:29:51.840> I'm 00:29:51.950 --> 00:29:51.960 align:start position:0% put it in your environment like if I'm 00:29:51.960 --> 00:29:54.169 align:start position:0% put it in your environment like if I'm swapping<00:29:52.559> something<00:29:53.220> then<00:29:53.760> I'm<00:29:54.000> getting 00:29:54.169 --> 00:29:54.179 align:start position:0% swapping something then I'm getting 00:29:54.179 --> 00:29:57.049 align:start position:0% swapping something then I'm getting something<00:29:54.539> else<00:29:55.320> right<00:29:55.980> and<00:29:56.520> in<00:29:56.700> that<00:29:56.820> case 00:29:57.049 --> 00:29:57.059 align:start position:0% something else right and in that case 00:29:57.059 --> 00:29:59.330 align:start position:0% something else right and in that case you<00:29:57.720> need<00:29:57.840> to<00:29:58.020> realize<00:29:58.380> that<00:29:58.740> it's<00:29:59.039> difficult 00:29:59.330 --> 00:29:59.340 align:start position:0% you need to realize that it's difficult 00:29:59.340 --> 00:30:01.490 align:start position:0% you need to realize that it's difficult to<00:29:59.580> write<00:29:59.760> invariants<00:30:00.419> with<00:30:00.960> other<00:30:01.200> people 00:30:01.490 --> 00:30:01.500 align:start position:0% to write invariants with other people 00:30:01.500 --> 00:30:04.610 align:start position:0% to write invariants with other people called<00:30:01.799> right<00:30:02.779> despite<00:30:03.779> despite<00:30:04.260> this<00:30:04.440> is 00:30:04.610 --> 00:30:04.620 align:start position:0% called right despite despite this is 00:30:04.620 --> 00:30:07.010 align:start position:0% called right despite despite this is working<00:30:04.980> and<00:30:05.399> everyone<00:30:05.580> is<00:30:05.880> is<00:30:06.059> using<00:30:06.480> it<00:30:06.600> but 00:30:07.010 --> 00:30:07.020 align:start position:0% working and everyone is is using it but 00:30:07.020 --> 00:30:09.590 align:start position:0% working and everyone is is using it but every<00:30:07.740> time<00:30:07.980> that<00:30:08.279> you<00:30:08.520> use<00:30:08.700> a<00:30:09.000> third-party 00:30:09.590 --> 00:30:09.600 align:start position:0% every time that you use a third-party 00:30:09.600 --> 00:30:12.889 align:start position:0% every time that you use a third-party contract<00:30:10.159> then<00:30:11.159> you<00:30:11.940> have<00:30:12.059> you<00:30:12.600> are 00:30:12.889 --> 00:30:12.899 align:start position:0% contract then you have you are 00:30:12.899 --> 00:30:15.049 align:start position:0% contract then you have you are importance<00:30:13.380> on<00:30:13.620> risk<00:30:13.980> and<00:30:14.580> you<00:30:14.760> need<00:30:14.880> to 00:30:15.049 --> 00:30:15.059 align:start position:0% importance on risk and you need to 00:30:15.059 --> 00:30:16.610 align:start position:0% importance on risk and you need to completely<00:30:15.419> understand<00:30:15.720> the<00:30:16.080> other<00:30:16.260> contract 00:30:16.610 --> 00:30:16.620 align:start position:0% completely understand the other contract 00:30:16.620 --> 00:30:18.590 align:start position:0% completely understand the other contract in<00:30:16.799> order<00:30:16.980> to<00:30:17.220> know<00:30:17.399> what<00:30:18.000> is<00:30:18.179> going<00:30:18.299> to<00:30:18.419> the 00:30:18.590 --> 00:30:18.600 align:start position:0% in order to know what is going to the 00:30:18.600 --> 00:30:27.130 align:start position:0% in order to know what is going to the effect<00:30:18.720> in<00:30:19.140> your<00:30:19.260> own<00:30:19.440> country<00:30:19.620> I 00:30:27.130 --> 00:30:27.140 align:start position:0% 00:30:27.140 --> 00:30:30.250 align:start position:0% so<00:30:28.140> there<00:30:28.440> is<00:30:28.679> case<00:30:28.799> was<00:30:29.100> we<00:30:29.340> have<00:30:29.580> a<00:30:29.820> special 00:30:30.250 --> 00:30:30.260 align:start position:0% so there is case was we have a special 00:30:30.260 --> 00:30:33.350 align:start position:0% so there is case was we have a special uh<00:30:31.260> I'm<00:30:31.500> from<00:30:31.679> gearbox<00:30:32.100> protocol<00:30:32.580> and<00:30:32.940> we<00:30:33.120> work 00:30:33.350 --> 00:30:33.360 align:start position:0% uh I'm from gearbox protocol and we work 00:30:33.360 --> 00:30:35.690 align:start position:0% uh I'm from gearbox protocol and we work on<00:30:33.720> composable<00:30:34.260> Leverage<00:30:34.620> and<00:30:35.220> we<00:30:35.460> have 00:30:35.690 --> 00:30:35.700 align:start position:0% on composable Leverage and we have 00:30:35.700 --> 00:30:38.149 align:start position:0% on composable Leverage and we have adapters<00:30:36.419> because<00:30:36.779> we<00:30:37.620> just<00:30:37.799> provide 00:30:38.149 --> 00:30:38.159 align:start position:0% adapters because we just provide 00:30:38.159 --> 00:30:41.269 align:start position:0% adapters because we just provide leverage<00:30:38.520> for<00:30:39.120> some<00:30:39.419> other<00:30:40.260> contracts<00:30:40.919> so 00:30:41.269 --> 00:30:41.279 align:start position:0% leverage for some other contracts so 00:30:41.279 --> 00:30:43.370 align:start position:0% leverage for some other contracts so when<00:30:41.520> you<00:30:41.700> combine<00:30:41.940> gearbox<00:30:42.360> with<00:30:42.600> uni<00:30:43.080> swap 00:30:43.370 --> 00:30:43.380 align:start position:0% when you combine gearbox with uni swap 00:30:43.380 --> 00:30:45.649 align:start position:0% when you combine gearbox with uni swap you<00:30:43.620> get<00:30:43.799> immediately 00:30:45.649 --> 00:30:45.659 align:start position:0% you get immediately 00:30:45.659 --> 00:30:48.289 align:start position:0% you get immediately um<00:30:46.140> margin<00:30:46.980> trading<00:30:47.340> and<00:30:47.580> in<00:30:47.700> this<00:30:47.880> case<00:30:48.000> it 00:30:48.289 --> 00:30:48.299 align:start position:0% um margin trading and in this case it 00:30:48.299 --> 00:30:50.450 align:start position:0% um margin trading and in this case it has<00:30:48.419> adapters<00:30:49.020> and<00:30:49.679> these<00:30:49.980> adapters 00:30:50.450 --> 00:30:50.460 align:start position:0% has adapters and these adapters 00:30:50.460 --> 00:30:54.529 align:start position:0% has adapters and these adapters incorrectly<00:30:51.179> Parts<00:30:51.799> path<00:30:52.799> to<00:30:53.520> make<00:30:53.760> check 00:30:54.529 --> 00:30:54.539 align:start position:0% incorrectly Parts path to make check 00:30:54.539 --> 00:30:57.529 align:start position:0% incorrectly Parts path to make check after<00:30:54.840> uni<00:30:55.380> swap<00:30:55.620> however<00:30:56.399> they<00:30:56.760> integrated 00:30:57.529 --> 00:30:57.539 align:start position:0% after uni swap however they integrated 00:30:57.539 --> 00:30:59.990 align:start position:0% after uni swap however they integrated and<00:30:57.960> may<00:30:58.200> call<00:30:58.440> to<00:30:58.679> existing<00:30:59.100> uni<00:30:59.520> Swap<00:30:59.760> and 00:30:59.990 --> 00:31:00.000 align:start position:0% and may call to existing uni Swap and 00:31:00.000 --> 00:31:02.810 align:start position:0% and may call to existing uni Swap and guy<00:31:00.419> who<00:31:00.840> were<00:31:01.380> on<00:31:01.620> immuneify<00:31:02.279> problem<00:31:02.460> he 00:31:02.810 --> 00:31:02.820 align:start position:0% guy who were on immuneify problem he 00:31:02.820 --> 00:31:05.630 align:start position:0% guy who were on immuneify problem he write<00:31:03.000> a<00:31:03.299> small<00:31:03.600> test<00:31:03.840> and<00:31:04.559> this<00:31:04.740> test<00:31:04.980> show<00:31:05.340> us 00:31:05.630 --> 00:31:05.640 align:start position:0% write a small test and this test show us 00:31:05.640 --> 00:31:09.409 align:start position:0% write a small test and this test show us that<00:31:06.240> if<00:31:06.659> you<00:31:06.899> really<00:31:07.080> add<00:31:07.500> some<00:31:08.419> additional 00:31:09.409 --> 00:31:09.419 align:start position:0% that if you really add some additional 00:31:09.419 --> 00:31:12.230 align:start position:0% that if you really add some additional part<00:31:09.840> of<00:31:10.080> call<00:31:10.320> data<00:31:10.860> it<00:31:11.820> could<00:31:12.000> be 00:31:12.230 --> 00:31:12.240 align:start position:0% part of call data it could be 00:31:12.240 --> 00:31:14.750 align:start position:0% part of call data it could be interpreted<00:31:12.899> incorrectly<00:31:13.740> so<00:31:14.159> we<00:31:14.399> have<00:31:14.520> two 00:31:14.750 --> 00:31:14.760 align:start position:0% interpreted incorrectly so we have two 00:31:14.760 --> 00:31:16.669 align:start position:0% interpreted incorrectly so we have two different<00:31:15.000> ones<00:31:15.480> our<00:31:15.840> system<00:31:16.140> could<00:31:16.500> be 00:31:16.669 --> 00:31:16.679 align:start position:0% different ones our system could be 00:31:16.679 --> 00:31:19.070 align:start position:0% different ones our system could be fooled<00:31:17.039> check<00:31:17.700> not 00:31:19.070 --> 00:31:19.080 align:start position:0% fooled check not 00:31:19.080 --> 00:31:21.590 align:start position:0% fooled check not Z<00:31:19.620> balance<00:31:20.039> which<00:31:20.279> should<00:31:20.520> be<00:31:20.640> checked<00:31:21.059> and<00:31:21.480> in 00:31:21.590 --> 00:31:21.600 align:start position:0% Z balance which should be checked and in 00:31:21.600 --> 00:31:23.570 align:start position:0% Z balance which should be checked and in this<00:31:21.779> case<00:31:21.960> it<00:31:22.380> was<00:31:22.500> a<00:31:22.740> fault<00:31:23.039> of<00:31:23.220> the<00:31:23.399> system 00:31:23.570 --> 00:31:23.580 align:start position:0% this case it was a fault of the system 00:31:23.580 --> 00:31:26.149 align:start position:0% this case it was a fault of the system and<00:31:23.940> the<00:31:24.360> funds<00:31:24.720> could<00:31:24.840> be<00:31:24.960> drained<00:31:25.440> and<00:31:25.980> in 00:31:26.149 --> 00:31:26.159 align:start position:0% and the funds could be drained and in 00:31:26.159 --> 00:31:28.250 align:start position:0% and the funds could be drained and in this<00:31:26.279> case<00:31:26.520> I<00:31:26.940> think<00:31:27.059> we<00:31:27.360> could<00:31:27.539> find<00:31:27.899> some 00:31:28.250 --> 00:31:28.260 align:start position:0% this case I think we could find some 00:31:28.260 --> 00:31:30.889 align:start position:0% this case I think we could find some fuzzing<00:31:28.679> testing<00:31:29.100> to<00:31:29.340> really<00:31:29.580> provide<00:31:30.419> any 00:31:30.889 --> 00:31:30.899 align:start position:0% fuzzing testing to really provide any 00:31:30.899 --> 00:31:33.289 align:start position:0% fuzzing testing to really provide any information<00:31:31.440> but<00:31:32.279> this<00:31:32.700> test<00:31:32.880> should<00:31:33.179> work 00:31:33.289 --> 00:31:33.299 align:start position:0% information but this test should work 00:31:33.299 --> 00:31:35.510 align:start position:0% information but this test should work with<00:31:33.480> uni<00:31:33.899> swap<00:31:34.140> because<00:31:34.500> we<00:31:35.039> behave<00:31:35.340> in 00:31:35.510 --> 00:31:35.520 align:start position:0% with uni swap because we behave in 00:31:35.520 --> 00:31:37.250 align:start position:0% with uni swap because we behave in different<00:31:35.700> way<00:31:36.059> and<00:31:36.600> we<00:31:36.840> shouldn't<00:31:37.080> cover 00:31:37.250 --> 00:31:37.260 align:start position:0% different way and we shouldn't cover 00:31:37.260 --> 00:31:39.950 align:start position:0% different way and we shouldn't cover that<00:31:37.620> because<00:31:37.860> we<00:31:38.159> run<00:31:38.340> with<00:31:38.520> mocks<00:31:39.059> and<00:31:39.539> MOX 00:31:39.950 --> 00:31:39.960 align:start position:0% that because we run with mocks and MOX 00:31:39.960 --> 00:31:41.870 align:start position:0% that because we run with mocks and MOX of<00:31:40.140> course<00:31:40.260> was<00:31:40.559> created<00:31:40.919> with<00:31:41.220> the<00:31:41.460> same<00:31:41.580> bug 00:31:41.870 --> 00:31:41.880 align:start position:0% of course was created with the same bug 00:31:41.880 --> 00:31:44.389 align:start position:0% of course was created with the same bug so<00:31:42.240> MOX<00:31:42.600> was<00:31:42.840> okay<00:31:43.020> but<00:31:43.620> real<00:31:43.799> implementation 00:31:44.389 --> 00:31:44.399 align:start position:0% so MOX was okay but real implementation 00:31:44.399 --> 00:31:46.730 align:start position:0% so MOX was okay but real implementation total<00:31:44.880> different<00:31:45.120> and<00:31:45.960> I<00:31:46.140> definitely<00:31:46.440> believe 00:31:46.730 --> 00:31:46.740 align:start position:0% total different and I definitely believe 00:31:46.740 --> 00:31:49.370 align:start position:0% total different and I definitely believe that<00:31:47.039> fuzzing<00:31:47.520> should<00:31:47.700> found<00:31:48.059> this<00:31:48.480> mistakes 00:31:49.370 --> 00:31:49.380 align:start position:0% that fuzzing should found this mistakes 00:31:49.380 --> 00:31:52.490 align:start position:0% that fuzzing should found this mistakes yeah<00:31:50.159> yeah<00:31:50.520> definitely<00:31:51.360> definitely<00:31:51.960> when<00:31:52.320> you 00:31:52.490 --> 00:31:52.500 align:start position:0% yeah yeah definitely definitely when you 00:31:52.500 --> 00:31:54.950 align:start position:0% yeah yeah definitely definitely when you are<00:31:52.679> creating<00:31:53.039> a<00:31:53.279> mock<00:31:53.520> you<00:31:54.120> are<00:31:54.240> assuming<00:31:54.659> how 00:31:54.950 --> 00:31:54.960 align:start position:0% are creating a mock you are assuming how 00:31:54.960 --> 00:31:56.870 align:start position:0% are creating a mock you are assuming how everything<00:31:55.200> works<00:31:55.740> and<00:31:56.100> if<00:31:56.279> your<00:31:56.399> assumption 00:31:56.870 --> 00:31:56.880 align:start position:0% everything works and if your assumption 00:31:56.880 --> 00:31:59.690 align:start position:0% everything works and if your assumption is<00:31:57.120> not<00:31:57.419> precise<00:31:58.020> enough<00:31:58.260> it<00:31:59.100> will<00:31:59.220> it<00:31:59.460> will 00:31:59.690 --> 00:31:59.700 align:start position:0% is not precise enough it will it will 00:31:59.700 --> 00:32:01.789 align:start position:0% is not precise enough it will it will you<00:32:00.240> won't<00:32:00.419> be<00:32:00.539> able<00:32:00.659> to<00:32:00.840> detect<00:32:01.380> something 00:32:01.789 --> 00:32:01.799 align:start position:0% you won't be able to detect something 00:32:01.799 --> 00:32:05.149 align:start position:0% you won't be able to detect something and<00:32:02.159> we<00:32:02.399> as<00:32:02.580> an<00:32:02.760> Auditors<00:32:03.440> it's<00:32:04.440> it's<00:32:04.620> common 00:32:05.149 --> 00:32:05.159 align:start position:0% and we as an Auditors it's it's common 00:32:05.159 --> 00:32:07.610 align:start position:0% and we as an Auditors it's it's common that<00:32:05.520> we<00:32:05.640> have<00:32:05.880> to<00:32:06.120> audit<00:32:06.720> contracts<00:32:07.440> that 00:32:07.610 --> 00:32:07.620 align:start position:0% that we have to audit contracts that 00:32:07.620 --> 00:32:09.289 align:start position:0% that we have to audit contracts that will<00:32:07.799> interact<00:32:08.220> with<00:32:08.340> other<00:32:08.580> other<00:32:08.820> contract 00:32:09.289 --> 00:32:09.299 align:start position:0% will interact with other other contract 00:32:09.299 --> 00:32:11.870 align:start position:0% will interact with other other contract let's<00:32:09.779> say<00:32:09.960> compound<00:32:10.440> so<00:32:11.100> when<00:32:11.399> we<00:32:11.580> go<00:32:11.700> into 00:32:11.870 --> 00:32:11.880 align:start position:0% let's say compound so when we go into 00:32:11.880 --> 00:32:13.430 align:start position:0% let's say compound so when we go into compound<00:32:12.299> we<00:32:12.539> have<00:32:12.659> all<00:32:12.779> the<00:32:12.960> documentation 00:32:13.430 --> 00:32:13.440 align:start position:0% compound we have all the documentation 00:32:13.440 --> 00:32:15.950 align:start position:0% compound we have all the documentation and<00:32:13.740> says<00:32:14.100> well<00:32:14.279> compound<00:32:15.000> word<00:32:15.179> like<00:32:15.480> this<00:32:15.659> or 00:32:15.950 --> 00:32:15.960 align:start position:0% and says well compound word like this or 00:32:15.960 --> 00:32:18.230 align:start position:0% and says well compound word like this or like<00:32:16.200> that<00:32:16.380> when<00:32:16.799> we<00:32:16.980> look<00:32:17.159> at<00:32:17.279> the<00:32:17.460> code<00:32:17.640> and 00:32:18.230 --> 00:32:18.240 align:start position:0% like that when we look at the code and 00:32:18.240 --> 00:32:21.169 align:start position:0% like that when we look at the code and see<00:32:18.539> some<00:32:19.140> things<00:32:19.740> are<00:32:20.039> not<00:32:20.279> documented<00:32:20.880> and 00:32:21.169 --> 00:32:21.179 align:start position:0% see some things are not documented and 00:32:21.179 --> 00:32:23.690 align:start position:0% see some things are not documented and we<00:32:21.360> go<00:32:21.539> back<00:32:21.840> into<00:32:22.080> the<00:32:22.500> developers<00:32:23.220> and<00:32:23.520> look 00:32:23.690 --> 00:32:23.700 align:start position:0% we go back into the developers and look 00:32:23.700 --> 00:32:25.730 align:start position:0% we go back into the developers and look look<00:32:23.940> if<00:32:24.360> you're<00:32:24.539> if<00:32:24.899> your<00:32:25.140> contract<00:32:25.440> is<00:32:25.620> doing 00:32:25.730 --> 00:32:25.740 align:start position:0% look if you're if your contract is doing 00:32:25.740 --> 00:32:27.649 align:start position:0% look if you're if your contract is doing this<00:32:25.919> so<00:32:26.039> that<00:32:26.279> it<00:32:26.399> will<00:32:26.580> revert<00:32:27.000> and<00:32:27.539> you're 00:32:27.649 --> 00:32:27.659 align:start position:0% this so that it will revert and you're 00:32:27.659 --> 00:32:31.010 align:start position:0% this so that it will revert and you're not<00:32:27.960> testing<00:32:28.620> for<00:32:28.799> that<00:32:28.980> so<00:32:29.880> it's<00:32:30.240> when<00:32:30.899> you 00:32:31.010 --> 00:32:31.020 align:start position:0% not testing for that so it's when you 00:32:31.020 --> 00:32:33.169 align:start position:0% not testing for that so it's when you when<00:32:31.320> you<00:32:31.500> are<00:32:31.620> using<00:32:31.860> a<00:32:32.039> third<00:32:32.220> party<00:32:32.520> uh 00:32:33.169 --> 00:32:33.179 align:start position:0% when you are using a third party uh 00:32:33.179 --> 00:32:35.750 align:start position:0% when you are using a third party uh contract<00:32:33.480> you<00:32:33.720> are<00:32:33.899> importing<00:32:34.380> the<00:32:34.559> risk<00:32:34.919> so 00:32:35.750 --> 00:32:35.760 align:start position:0% contract you are importing the risk so 00:32:35.760 --> 00:32:38.870 align:start position:0% contract you are importing the risk so either<00:32:36.360> either<00:32:36.779> you<00:32:37.380> have<00:32:37.679> really<00:32:38.039> good<00:32:38.279> tests 00:32:38.870 --> 00:32:38.880 align:start position:0% either either you have really good tests 00:32:38.880 --> 00:32:42.169 align:start position:0% either either you have really good tests or<00:32:39.720> you<00:32:40.020> even<00:32:40.279> uh<00:32:41.279> make<00:32:41.580> sure<00:32:41.760> that<00:32:42.059> you 00:32:42.169 --> 00:32:42.179 align:start position:0% or you even uh make sure that you 00:32:42.179 --> 00:32:44.750 align:start position:0% or you even uh make sure that you understand<00:32:42.360> everything<00:32:43.279> otherwise<00:32:44.279> it<00:32:44.640> will 00:32:44.750 --> 00:32:44.760 align:start position:0% understand everything otherwise it will 00:32:44.760 --> 00:32:47.810 align:start position:0% understand everything otherwise it will be<00:32:44.880> difficult<00:32:45.360> to<00:32:45.659> catch<00:32:45.960> the<00:32:46.260> uh<00:32:46.620> but<00:32:47.460> yeah<00:32:47.640> I 00:32:47.810 --> 00:32:47.820 align:start position:0% be difficult to catch the uh but yeah I 00:32:47.820 --> 00:32:49.130 align:start position:0% be difficult to catch the uh but yeah I think<00:32:48.120> this<00:32:48.240> type<00:32:48.419> of<00:32:48.539> work<00:32:48.659> can<00:32:48.899> be<00:32:49.020> found 00:32:49.130 --> 00:32:49.140 align:start position:0% think this type of work can be found 00:32:49.140 --> 00:32:50.750 align:start position:0% think this type of work can be found with<00:32:49.320> fuzzing<00:32:49.740> like<00:32:49.980> the<00:32:50.100> most<00:32:50.279> like<00:32:50.520> the 00:32:50.750 --> 00:32:50.760 align:start position:0% with fuzzing like the most like the 00:32:50.760 --> 00:32:52.909 align:start position:0% with fuzzing like the most like the difficulty<00:32:51.299> is<00:32:51.600> going<00:32:51.840> to<00:32:52.260> find 00:32:52.909 --> 00:32:52.919 align:start position:0% difficulty is going to find 00:32:52.919 --> 00:32:54.710 align:start position:0% difficulty is going to find initialization<00:32:53.700> that<00:32:54.000> makes<00:32:54.120> sense<00:32:54.299> and<00:32:54.539> then 00:32:54.710 --> 00:32:54.720 align:start position:0% initialization that makes sense and then 00:32:54.720 --> 00:32:56.450 align:start position:0% initialization that makes sense and then that<00:32:55.260> makes<00:32:55.380> sense 00:32:56.450 --> 00:32:56.460 align:start position:0% that makes sense 00:32:56.460 --> 00:32:57.950 align:start position:0% that makes sense um<00:32:56.520> that's<00:32:56.820> why<00:32:57.000> that's<00:32:57.120> why<00:32:57.360> you<00:32:57.480> know<00:32:57.600> we<00:32:57.779> are 00:32:57.950 --> 00:32:57.960 align:start position:0% um that's why that's why you know we are 00:32:57.960 --> 00:33:00.110 align:start position:0% um that's why that's why you know we are kind<00:32:58.320> of<00:32:58.500> in<00:32:58.740> putting<00:32:59.279> like<00:32:59.460> the<00:32:59.640> infances 00:33:00.110 --> 00:33:00.120 align:start position:0% kind of in putting like the infances 00:33:00.120 --> 00:33:01.970 align:start position:0% kind of in putting like the infances onto<00:33:00.539> defining<00:33:01.080> environment<00:33:01.500> because<00:33:01.740> this 00:33:01.970 --> 00:33:01.980 align:start position:0% onto defining environment because this 00:33:01.980 --> 00:33:03.409 align:start position:0% onto defining environment because this is<00:33:02.100> like<00:33:02.279> the<00:33:02.460> key<00:33:02.700> component<00:33:03.059> of<00:33:03.240> this 00:33:03.409 --> 00:33:03.419 align:start position:0% is like the key component of this 00:33:03.419 --> 00:33:04.909 align:start position:0% is like the key component of this technique<00:33:03.779> yeah 00:33:04.909 --> 00:33:04.919 align:start position:0% technique yeah 00:33:04.919 --> 00:33:05.930 align:start position:0% technique yeah uh 00:33:05.930 --> 00:33:05.940 align:start position:0% uh 00:33:05.940 --> 00:33:09.289 align:start position:0% uh in<00:33:06.120> terms<00:33:06.860> in<00:33:07.860> terms<00:33:08.039> of<00:33:08.100> speed<00:33:08.279> is<00:33:08.520> it<00:33:08.700> okay<00:33:08.820> to 00:33:09.289 --> 00:33:09.299 align:start position:0% in terms in terms of speed is it okay to 00:33:09.299 --> 00:33:11.750 align:start position:0% in terms in terms of speed is it okay to put<00:33:09.539> all<00:33:10.080> deployment<00:33:10.799> script<00:33:11.399> into 00:33:11.750 --> 00:33:11.760 align:start position:0% put all deployment script into 00:33:11.760 --> 00:33:13.789 align:start position:0% put all deployment script into Constructor<00:33:12.360> because<00:33:12.720> of<00:33:13.019> course<00:33:13.200> if<00:33:13.679> you 00:33:13.789 --> 00:33:13.799 align:start position:0% Constructor because of course if you 00:33:13.799 --> 00:33:16.730 align:start position:0% Constructor because of course if you deploy<00:33:14.220> such<00:33:15.000> a<00:33:15.120> huge<00:33:15.480> system<00:33:15.720> and<00:33:16.140> you<00:33:16.260> deploy 00:33:16.730 --> 00:33:16.740 align:start position:0% deploy such a huge system and you deploy 00:33:16.740 --> 00:33:19.190 align:start position:0% deploy such a huge system and you deploy some<00:33:17.039> contracts<00:33:17.580> from<00:33:18.360> external 00:33:19.190 --> 00:33:19.200 align:start position:0% some contracts from external 00:33:19.200 --> 00:33:21.169 align:start position:0% some contracts from external repositories<00:33:19.740> like<00:33:19.980> uni<00:33:20.340> Swap<00:33:20.580> and<00:33:20.760> so<00:33:20.940> on<00:33:21.059> it 00:33:21.169 --> 00:33:21.179 align:start position:0% repositories like uni Swap and so on it 00:33:21.179 --> 00:33:23.330 align:start position:0% repositories like uni Swap and so on it requires<00:33:21.659> time<00:33:21.899> and<00:33:22.559> of<00:33:22.679> course<00:33:22.860> when<00:33:23.159> you 00:33:23.330 --> 00:33:23.340 align:start position:0% requires time and of course when you 00:33:23.340 --> 00:33:25.549 align:start position:0% requires time and of course when you want<00:33:23.519> to<00:33:23.700> test<00:33:23.880> million<00:33:24.419> operation<00:33:24.899> if<00:33:25.440> you 00:33:25.549 --> 00:33:25.559 align:start position:0% want to test million operation if you 00:33:25.559 --> 00:33:28.130 align:start position:0% want to test million operation if you redeploy<00:33:26.039> each<00:33:26.340> time<00:33:26.580> holds<00:33:27.539> the<00:33:27.659> system<00:33:27.779> it 00:33:28.130 --> 00:33:28.140 align:start position:0% redeploy each time holds the system it 00:33:28.140 --> 00:33:30.590 align:start position:0% redeploy each time holds the system it could<00:33:28.320> require<00:33:28.440> hours<00:33:29.039> or<00:33:29.519> days<00:33:29.760> I<00:33:30.059> know<00:33:30.240> yeah 00:33:30.590 --> 00:33:30.600 align:start position:0% could require hours or days I know yeah 00:33:30.600 --> 00:33:33.049 align:start position:0% could require hours or days I know yeah so<00:33:30.779> so<00:33:30.960> so<00:33:31.080> when<00:33:31.679> you<00:33:31.919> use<00:33:32.159> Echidna<00:33:32.760> you 00:33:33.049 --> 00:33:33.059 align:start position:0% so so so when you use Echidna you 00:33:33.059 --> 00:33:36.409 align:start position:0% so so so when you use Echidna you deploys<00:33:33.480> only<00:33:33.720> once<00:33:34.200> and<00:33:35.039> then<00:33:35.220> the<00:33:35.760> when<00:33:36.179> your 00:33:36.409 --> 00:33:36.419 align:start position:0% deploys only once and then the when your 00:33:36.419 --> 00:33:38.269 align:start position:0% deploys only once and then the when your test<00:33:36.600> finish<00:33:36.899> it<00:33:37.200> will<00:33:37.380> go<00:33:37.679> back<00:33:37.799> to<00:33:38.039> the 00:33:38.269 --> 00:33:38.279 align:start position:0% test finish it will go back to the 00:33:38.279 --> 00:33:40.070 align:start position:0% test finish it will go back to the states<00:33:38.519> after<00:33:39.000> the<00:33:39.179> contract<00:33:39.480> is<00:33:39.659> deployed 00:33:40.070 --> 00:33:40.080 align:start position:0% states after the contract is deployed 00:33:40.080 --> 00:33:43.850 align:start position:0% states after the contract is deployed there's<00:33:40.500> no<00:33:40.799> need<00:33:40.980> to<00:33:41.159> redeploy<00:33:41.640> it<00:33:41.820> and<00:33:43.080> that 00:33:43.850 --> 00:33:43.860 align:start position:0% there's no need to redeploy it and that 00:33:43.860 --> 00:33:46.909 align:start position:0% there's no need to redeploy it and that is<00:33:44.039> why<00:33:44.340> we<00:33:44.700> have<00:33:44.940> we<00:33:45.840> we<00:33:46.019> ask<00:33:46.320> the<00:33:46.500> developer 00:33:46.909 --> 00:33:46.919 align:start position:0% is why we have we we ask the developer 00:33:46.919 --> 00:33:49.549 align:start position:0% is why we have we we ask the developer to<00:33:47.100> have<00:33:47.340> fixed<00:33:47.880> amount<00:33:48.240> of<00:33:48.360> parameters<00:33:49.320> in 00:33:49.549 --> 00:33:49.559 align:start position:0% to have fixed amount of parameters in 00:33:49.559 --> 00:33:52.130 align:start position:0% to have fixed amount of parameters in the<00:33:49.740> deployment<00:33:50.120> right<00:33:51.120> on<00:33:51.360> the<00:33:51.480> on<00:33:51.659> the<00:33:51.840> on 00:33:52.130 --> 00:33:52.140 align:start position:0% the deployment right on the on the on 00:33:52.140 --> 00:33:54.649 align:start position:0% the deployment right on the on the on the<00:33:52.260> Constructor<00:33:52.700> otherwise<00:33:53.700> we<00:33:54.120> will<00:33:54.299> know 00:33:54.649 --> 00:33:54.659 align:start position:0% the Constructor otherwise we will know 00:33:54.659 --> 00:33:56.810 align:start position:0% the Constructor otherwise we will know what<00:33:54.960> what<00:33:55.260> we<00:33:55.500> should<00:33:55.620> deploy<00:33:56.039> yeah<00:33:56.519> I<00:33:56.760> think 00:33:56.810 --> 00:33:56.820 align:start position:0% what what we should deploy yeah I think 00:33:56.820 --> 00:34:00.889 align:start position:0% what what we should deploy yeah I think there<00:33:57.120> is<00:33:57.240> a<00:33:57.360> question<00:33:57.539> over<00:33:57.779> there<00:33:58.019> also 00:34:00.889 --> 00:34:00.899 align:start position:0% 00:34:00.899 --> 00:34:03.889 align:start position:0% um<00:34:01.080> I'm<00:34:01.860> just<00:34:01.919> wondering<00:34:02.220> as<00:34:02.580> you<00:34:02.820> uh<00:34:03.419> once 00:34:03.889 --> 00:34:03.899 align:start position:0% um I'm just wondering as you uh once 00:34:03.899 --> 00:34:06.049 align:start position:0% um I'm just wondering as you uh once you've<00:34:04.080> kind<00:34:04.380> of<00:34:04.500> defined<00:34:04.740> your<00:34:04.919> invariance 00:34:06.049 --> 00:34:06.059 align:start position:0% you've kind of defined your invariance 00:34:06.059 --> 00:34:09.649 align:start position:0% you've kind of defined your invariance um<00:34:06.179> and<00:34:06.960> I<00:34:07.860> imagine<00:34:08.460> you<00:34:08.760> guys<00:34:08.940> in<00:34:09.060> your<00:34:09.240> audits 00:34:09.649 --> 00:34:09.659 align:start position:0% um and I imagine you guys in your audits 00:34:09.659 --> 00:34:11.990 align:start position:0% um and I imagine you guys in your audits you<00:34:09.720> you<00:34:09.960> run<00:34:10.260> through<00:34:10.500> these<00:34:10.859> and 00:34:11.990 --> 00:34:12.000 align:start position:0% you you run through these and 00:34:12.000 --> 00:34:13.550 align:start position:0% you you run through these and um 00:34:13.550 --> 00:34:13.560 align:start position:0% um 00:34:13.560 --> 00:34:15.589 align:start position:0% um basically<00:34:14.159> I'm<00:34:14.339> not<00:34:14.520> trying<00:34:14.879> to<00:34:15.119> understand 00:34:15.589 --> 00:34:15.599 align:start position:0% basically I'm not trying to understand 00:34:15.599 --> 00:34:18.589 align:start position:0% basically I'm not trying to understand when<00:34:16.320> you<00:34:16.500> guys<00:34:16.619> have<00:34:16.859> confidence<00:34:17.280> that<00:34:17.760> yes 00:34:18.589 --> 00:34:18.599 align:start position:0% when you guys have confidence that yes 00:34:18.599 --> 00:34:21.649 align:start position:0% when you guys have confidence that yes the<00:34:19.020> this<00:34:19.440> is<00:34:19.619> a<00:34:19.800> good<00:34:19.919> invariance<00:34:20.580> uh<00:34:21.359> from 00:34:21.649 --> 00:34:21.659 align:start position:0% the this is a good invariance uh from 00:34:21.659 --> 00:34:23.570 align:start position:0% the this is a good invariance uh from and<00:34:22.139> and<00:34:22.320> if<00:34:22.560> there<00:34:22.740> are<00:34:22.859> any<00:34:22.980> metrics<00:34:23.399> that 00:34:23.570 --> 00:34:23.580 align:start position:0% and and if there are any metrics that 00:34:23.580 --> 00:34:26.510 align:start position:0% and and if there are any metrics that you<00:34:23.700> guys<00:34:23.820> use<00:34:24.179> uh<00:34:24.960> internally<00:34:25.379> like<00:34:26.099> I<00:34:26.399> see 00:34:26.510 --> 00:34:26.520 align:start position:0% you guys use uh internally like I see 00:34:26.520 --> 00:34:29.389 align:start position:0% you guys use uh internally like I see it's<00:34:26.760> outputting<00:34:27.540> Unique<00:34:28.200> instructions<00:34:29.040> and 00:34:29.389 --> 00:34:29.399 align:start position:0% it's outputting Unique instructions and 00:34:29.399 --> 00:34:31.609 align:start position:0% it's outputting Unique instructions and unique<00:34:29.760> code<00:34:29.940> hashes<00:34:30.419> those<00:34:30.960> sorts<00:34:31.320> of<00:34:31.320> things 00:34:31.609 --> 00:34:31.619 align:start position:0% unique code hashes those sorts of things 00:34:31.619 --> 00:34:34.849 align:start position:0% unique code hashes those sorts of things that<00:34:32.099> uh<00:34:32.639> give<00:34:33.240> you<00:34:33.419> confidence<00:34:33.839> in<00:34:34.320> in<00:34:34.560> what 00:34:34.849 --> 00:34:34.859 align:start position:0% that uh give you confidence in in what 00:34:34.859 --> 00:34:36.050 align:start position:0% that uh give you confidence in in what you've<00:34:35.040> done 00:34:36.050 --> 00:34:36.060 align:start position:0% you've done 00:34:36.060 --> 00:34:38.629 align:start position:0% you've done so<00:34:36.720> in<00:34:37.080> practice<00:34:37.440> you<00:34:37.800> know<00:34:37.919> you<00:34:38.099> can<00:34:38.220> look<00:34:38.399> at 00:34:38.629 --> 00:34:38.639 align:start position:0% so in practice you know you can look at 00:34:38.639 --> 00:34:40.550 align:start position:0% so in practice you know you can look at the<00:34:38.879> coverage<00:34:39.240> but<00:34:39.480> usually<00:34:39.780> coverage<00:34:40.139> is<00:34:40.379> not 00:34:40.550 --> 00:34:40.560 align:start position:0% the coverage but usually coverage is not 00:34:40.560 --> 00:34:43.250 align:start position:0% the coverage but usually coverage is not a<00:34:40.679> good<00:34:40.800> indicator<00:34:41.220> and<00:34:42.179> In<00:34:42.419> fairness<00:34:42.839> like 00:34:43.250 --> 00:34:43.260 align:start position:0% a good indicator and In fairness like 00:34:43.260 --> 00:34:45.889 align:start position:0% a good indicator and In fairness like you<00:34:43.560> know<00:34:43.679> when<00:34:44.159> we<00:34:44.399> do<00:34:44.580> that<00:34:44.700> we<00:34:44.940> do<00:34:45.119> this<00:34:45.359> in<00:34:45.720> a 00:34:45.889 --> 00:34:45.899 align:start position:0% you know when we do that we do this in a 00:34:45.899 --> 00:34:48.710 align:start position:0% you know when we do that we do this in a time<00:34:46.080> box<00:34:46.320> manner<00:34:46.859> so<00:34:47.520> we<00:34:47.879> have<00:34:48.060> two<00:34:48.359> or<00:34:48.540> three 00:34:48.710 --> 00:34:48.720 align:start position:0% time box manner so we have two or three 00:34:48.720 --> 00:34:50.149 align:start position:0% time box manner so we have two or three weeks<00:34:49.020> to<00:34:49.080> do<00:34:49.200> it<00:34:49.320> and<00:34:49.440> we're<00:34:49.619> going<00:34:49.800> to<00:34:49.859> do<00:34:49.980> our 00:34:50.149 --> 00:34:50.159 align:start position:0% weeks to do it and we're going to do our 00:34:50.159 --> 00:34:53.030 align:start position:0% weeks to do it and we're going to do our best<00:34:50.280> in<00:34:50.580> two<00:34:50.760> or<00:34:50.879> three<00:34:51.060> weeks<00:34:51.560> uh<00:34:52.560> that's<00:34:52.859> the 00:34:53.030 --> 00:34:53.040 align:start position:0% best in two or three weeks uh that's the 00:34:53.040 --> 00:34:55.909 align:start position:0% best in two or three weeks uh that's the best<00:34:53.159> that<00:34:53.339> we<00:34:53.520> can<00:34:53.639> do<00:34:53.760> yeah<00:34:54.359> it's<00:34:54.599> it's<00:34:54.899> it's 00:34:55.909 --> 00:34:55.919 align:start position:0% best that we can do yeah it's it's it's 00:34:55.919 --> 00:34:59.329 align:start position:0% best that we can do yeah it's it's it's we<00:34:56.339> there<00:34:56.760> is<00:34:56.940> no 00:34:59.329 --> 00:34:59.339 align:start position:0% 00:34:59.339 --> 00:35:02.450 align:start position:0% uh<00:34:59.880> Silver<00:35:00.060> Bullet<00:35:00.540> for<00:35:00.780> this 00:35:02.450 --> 00:35:02.460 align:start position:0% uh Silver Bullet for this 00:35:02.460 --> 00:35:03.770 align:start position:0% uh Silver Bullet for this um<00:35:02.520> it 00:35:03.770 --> 00:35:03.780 align:start position:0% um it 00:35:03.780 --> 00:35:07.849 align:start position:0% um it we<00:35:04.680> when<00:35:05.160> we<00:35:05.400> do<00:35:05.640> a<00:35:06.119> report<00:35:06.420> we<00:35:07.260> list<00:35:07.440> the 00:35:07.849 --> 00:35:07.859 align:start position:0% we when we do a report we list the 00:35:07.859 --> 00:35:10.730 align:start position:0% we when we do a report we list the invariance<00:35:08.339> that<00:35:08.520> we<00:35:08.700> test<00:35:08.960> so<00:35:09.960> it's<00:35:10.380> it's 00:35:10.730 --> 00:35:10.740 align:start position:0% invariance that we test so it's it's 00:35:10.740 --> 00:35:13.670 align:start position:0% invariance that we test so it's it's clear<00:35:11.160> what<00:35:11.760> what<00:35:12.060> we<00:35:12.359> tested<00:35:12.839> and<00:35:13.200> what<00:35:13.380> and 00:35:13.670 --> 00:35:13.680 align:start position:0% clear what what we tested and what and 00:35:13.680 --> 00:35:15.589 align:start position:0% clear what what we tested and what and everything<00:35:13.859> else<00:35:14.160> was<00:35:14.460> was<00:35:14.760> not<00:35:15.000> tested<00:35:15.359> with 00:35:15.589 --> 00:35:15.599 align:start position:0% everything else was was not tested with 00:35:15.599 --> 00:35:18.109 align:start position:0% everything else was was not tested with all<00:35:15.839> so<00:35:16.079> we<00:35:16.380> will<00:35:16.560> perhaps<00:35:16.980> did<00:35:17.220> Manual<00:35:17.940> review 00:35:18.109 --> 00:35:18.119 align:start position:0% all so we will perhaps did Manual review 00:35:18.119 --> 00:35:20.210 align:start position:0% all so we will perhaps did Manual review or<00:35:18.540> use<00:35:18.780> all<00:35:19.079> the<00:35:19.260> techniques<00:35:19.619> like<00:35:19.800> Slither 00:35:20.210 --> 00:35:20.220 align:start position:0% or use all the techniques like Slither 00:35:20.220 --> 00:35:23.270 align:start position:0% or use all the techniques like Slither to<00:35:20.520> check<00:35:20.700> some<00:35:21.119> some<00:35:21.599> other<00:35:21.900> things<00:35:22.200> uh<00:35:23.160> but 00:35:23.270 --> 00:35:23.280 align:start position:0% to check some some other things uh but 00:35:23.280 --> 00:35:25.910 align:start position:0% to check some some other things uh but yeah<00:35:23.460> unfortunately<00:35:23.880> there<00:35:24.240> is<00:35:24.420> no<00:35:24.780> uh<00:35:25.560> good 00:35:25.910 --> 00:35:25.920 align:start position:0% yeah unfortunately there is no uh good 00:35:25.920 --> 00:35:30.410 align:start position:0% yeah unfortunately there is no uh good way<00:35:26.280> to<00:35:26.640> to<00:35:26.940> Define<00:35:27.240> this<00:35:27.800> uh<00:35:28.800> but<00:35:29.099> perhaps<00:35:29.579> I<00:35:30.060> I 00:35:30.410 --> 00:35:30.420 align:start position:0% way to to Define this uh but perhaps I I 00:35:30.420 --> 00:35:32.510 align:start position:0% way to to Define this uh but perhaps I I personally<00:35:30.839> think<00:35:31.079> that<00:35:31.440> talking<00:35:31.859> with<00:35:32.280> the 00:35:32.510 --> 00:35:32.520 align:start position:0% personally think that talking with the 00:35:32.520 --> 00:35:35.870 align:start position:0% personally think that talking with the developer<00:35:33.000> early<00:35:33.480> on<00:35:33.900> the<00:35:34.079> invariance<00:35:34.640> it's<00:35:35.640> a 00:35:35.870 --> 00:35:35.880 align:start position:0% developer early on the invariance it's a 00:35:35.880 --> 00:35:38.089 align:start position:0% developer early on the invariance it's a really<00:35:35.940> good<00:35:36.180> thing<00:35:36.480> it's<00:35:37.320> usually<00:35:37.680> the<00:35:37.920> case 00:35:38.089 --> 00:35:38.099 align:start position:0% really good thing it's usually the case 00:35:38.099 --> 00:35:40.370 align:start position:0% really good thing it's usually the case that<00:35:38.520> we<00:35:39.000> think<00:35:39.180> an<00:35:39.420> in<00:35:39.599> barrient<00:35:40.020> let's<00:35:40.200> say 00:35:40.370 --> 00:35:40.380 align:start position:0% that we think an in barrient let's say 00:35:40.380 --> 00:35:43.790 align:start position:0% that we think an in barrient let's say that<00:35:40.920> some<00:35:41.520> some<00:35:41.820> value<00:35:42.300> cannot<00:35:42.839> be<00:35:42.960> zero<00:35:43.440> and 00:35:43.790 --> 00:35:43.800 align:start position:0% that some some value cannot be zero and 00:35:43.800 --> 00:35:46.730 align:start position:0% that some some value cannot be zero and we<00:35:43.980> go<00:35:44.160> into<00:35:44.280> the<00:35:44.579> into<00:35:45.060> the<00:35:45.300> client<00:35:46.020> and<00:35:46.500> says 00:35:46.730 --> 00:35:46.740 align:start position:0% we go into the into the client and says 00:35:46.740 --> 00:35:48.770 align:start position:0% we go into the into the client and says is<00:35:47.040> this<00:35:47.400> an<00:35:47.579> invariant<00:35:48.000> we<00:35:48.480> don't<00:35:48.660> know 00:35:48.770 --> 00:35:48.780 align:start position:0% is this an invariant we don't know 00:35:48.780 --> 00:35:50.510 align:start position:0% is this an invariant we don't know because<00:35:49.020> we<00:35:49.260> have<00:35:49.440> not<00:35:49.619> designed<00:35:50.220> the<00:35:50.280> system 00:35:50.510 --> 00:35:50.520 align:start position:0% because we have not designed the system 00:35:50.520 --> 00:35:53.089 align:start position:0% because we have not designed the system and<00:35:51.180> they<00:35:51.300> don't<00:35:51.420> know<00:35:52.020> and<00:35:52.560> if<00:35:52.740> they<00:35:52.920> don't 00:35:53.089 --> 00:35:53.099 align:start position:0% and they don't know and if they don't 00:35:53.099 --> 00:35:55.190 align:start position:0% and they don't know and if they don't know<00:35:53.280> that's<00:35:53.760> that's<00:35:54.000> an<00:35:54.240> issue<00:35:54.540> right<00:35:54.900> we 00:35:55.190 --> 00:35:55.200 align:start position:0% know that's that's an issue right we 00:35:55.200 --> 00:35:58.130 align:start position:0% know that's that's an issue right we should<00:35:55.619> we<00:35:55.980> should<00:35:56.220> absolutely<00:35:57.060> know<00:35:57.480> what<00:35:58.020> is 00:35:58.130 --> 00:35:58.140 align:start position:0% should we should absolutely know what is 00:35:58.140 --> 00:36:00.829 align:start position:0% should we should absolutely know what is the<00:35:58.320> behavior<00:35:58.680> of<00:35:58.980> the<00:35:59.099> system<00:35:59.280> and<00:36:00.180> and<00:36:00.420> if<00:36:00.720> we 00:36:00.829 --> 00:36:00.839 align:start position:0% the behavior of the system and and if we 00:36:00.839 --> 00:36:02.930 align:start position:0% the behavior of the system and and if we don't<00:36:00.960> know<00:36:01.079> if<00:36:01.200> anybody<00:36:01.619> should<00:36:01.980> should<00:36:02.520> if 00:36:02.930 --> 00:36:02.940 align:start position:0% don't know if anybody should should if 00:36:02.940 --> 00:36:04.130 align:start position:0% don't know if anybody should should if something<00:36:03.119> should<00:36:03.359> be<00:36:03.540> an<00:36:03.599> environment<00:36:03.960> or 00:36:04.130 --> 00:36:04.140 align:start position:0% something should be an environment or 00:36:04.140 --> 00:36:06.410 align:start position:0% something should be an environment or not<00:36:04.200> then<00:36:04.440> we<00:36:04.859> should<00:36:05.040> go<00:36:05.220> back<00:36:05.400> and<00:36:05.640> rediscus 00:36:06.410 --> 00:36:06.420 align:start position:0% not then we should go back and rediscus 00:36:06.420 --> 00:36:08.630 align:start position:0% not then we should go back and rediscus that<00:36:06.599> and<00:36:07.079> yeah<00:36:07.260> Security<00:36:07.500> in<00:36:07.980> general<00:36:08.099> is<00:36:08.460> not 00:36:08.630 --> 00:36:08.640 align:start position:0% that and yeah Security in general is not 00:36:08.640 --> 00:36:11.030 align:start position:0% that and yeah Security in general is not binary<00:36:09.060> it's<00:36:09.300> not<00:36:09.480> you<00:36:09.599> know<00:36:09.660> yes<00:36:09.960> or<00:36:10.200> no<00:36:10.380> it's 00:36:11.030 --> 00:36:11.040 align:start position:0% binary it's not you know yes or no it's 00:36:11.040 --> 00:36:12.829 align:start position:0% binary it's not you know yes or no it's really<00:36:11.220> a<00:36:11.400> matter<00:36:11.520> of<00:36:11.700> how<00:36:12.060> much<00:36:12.180> resource<00:36:12.720> you 00:36:12.829 --> 00:36:12.839 align:start position:0% really a matter of how much resource you 00:36:12.839 --> 00:36:14.990 align:start position:0% really a matter of how much resource you want<00:36:12.960> to<00:36:13.020> put<00:36:13.140> into<00:36:13.380> it<00:36:13.680> and<00:36:14.160> moreover<00:36:14.760> social 00:36:14.990 --> 00:36:15.000 align:start position:0% want to put into it and moreover social 00:36:15.000 --> 00:36:20.530 align:start position:0% want to put into it and moreover social put<00:36:15.359> more<00:36:15.839> confidential 00:36:20.530 --> 00:36:20.540 align:start position:0% 00:36:20.540 --> 00:36:22.750 align:start position:0% thank<00:36:21.540> you 00:36:22.750 --> 00:36:22.760 align:start position:0% thank you 00:36:22.760 --> 00:36:25.130 align:start position:0% thank you thanks<00:36:23.760> I<00:36:24.060> have<00:36:24.240> a<00:36:24.359> question<00:36:24.599> actually<00:36:24.900> more 00:36:25.130 --> 00:36:25.140 align:start position:0% thanks I have a question actually more 00:36:25.140 --> 00:36:27.890 align:start position:0% thanks I have a question actually more related<00:36:25.500> to<00:36:25.859> the<00:36:26.099> earlier<00:36:26.520> question<00:36:26.820> which<00:36:27.720> is 00:36:27.890 --> 00:36:27.900 align:start position:0% related to the earlier question which is 00:36:27.900 --> 00:36:29.329 align:start position:0% related to the earlier question which is a<00:36:28.500> big 00:36:29.329 --> 00:36:29.339 align:start position:0% a big 00:36:29.339 --> 00:36:31.490 align:start position:0% a big uh<00:36:30.000> class<00:36:30.180> of<00:36:30.420> bugs<00:36:30.780> that's<00:36:30.960> been<00:36:31.140> occurring 00:36:31.490 --> 00:36:31.500 align:start position:0% uh class of bugs that's been occurring 00:36:31.500 --> 00:36:33.589 align:start position:0% uh class of bugs that's been occurring recently<00:36:31.920> and<00:36:32.400> for<00:36:32.640> a<00:36:33.000> while<00:36:33.119> now<00:36:33.359> are 00:36:33.589 --> 00:36:33.599 align:start position:0% recently and for a while now are 00:36:33.599 --> 00:36:36.710 align:start position:0% recently and for a while now are re-entrancy<00:36:34.320> bugs<00:36:34.740> right<00:36:35.099> how<00:36:35.460> do<00:36:35.579> you<00:36:35.700> deal 00:36:36.710 --> 00:36:36.720 align:start position:0% re-entrancy bugs right how do you deal 00:36:36.720 --> 00:36:39.410 align:start position:0% re-entrancy bugs right how do you deal with<00:36:37.619> finding 00:36:39.410 --> 00:36:39.420 align:start position:0% with finding 00:36:39.420 --> 00:36:41.569 align:start position:0% with finding um<00:36:39.480> violations<00:36:40.380> of<00:36:40.680> invariance<00:36:41.280> that 00:36:41.569 --> 00:36:41.579 align:start position:0% um violations of invariance that 00:36:41.579 --> 00:36:43.790 align:start position:0% um violations of invariance that correspond<00:36:42.119> to<00:36:42.240> external<00:36:42.720> contracts<00:36:43.260> in<00:36:43.560> that 00:36:43.790 --> 00:36:43.800 align:start position:0% correspond to external contracts in that 00:36:43.800 --> 00:36:45.589 align:start position:0% correspond to external contracts in that way 00:36:45.589 --> 00:36:45.599 align:start position:0% way 00:36:45.599 --> 00:36:47.150 align:start position:0% way okay<00:36:45.780> so<00:36:46.200> this<00:36:46.380> is<00:36:46.500> a<00:36:46.619> really<00:36:46.740> good<00:36:46.980> question 00:36:47.150 --> 00:36:47.160 align:start position:0% okay so this is a really good question 00:36:47.160 --> 00:36:50.030 align:start position:0% okay so this is a really good question and<00:36:47.640> in<00:36:47.820> my<00:36:48.000> opinion<00:36:48.359> the<00:36:49.320> best<00:36:49.560> tool<00:36:49.859> to<00:36:49.920> find 00:36:50.030 --> 00:36:50.040 align:start position:0% and in my opinion the best tool to find 00:36:50.040 --> 00:36:53.690 align:start position:0% and in my opinion the best tool to find way<00:36:50.220> on<00:36:50.460> Transit<00:36:50.760> is<00:36:50.940> static<00:36:51.300> analysis<00:36:52.200> so<00:36:53.040> the 00:36:53.690 --> 00:36:53.700 align:start position:0% way on Transit is static analysis so the 00:36:53.700 --> 00:36:56.390 align:start position:0% way on Transit is static analysis so the question<00:36:54.300> is<00:36:54.599> more<00:36:54.780> to<00:36:55.020> find<00:36:55.260> which<00:36:55.980> technique 00:36:56.390 --> 00:36:56.400 align:start position:0% question is more to find which technique 00:36:56.400 --> 00:36:59.089 align:start position:0% question is more to find which technique you<00:36:56.760> should<00:36:56.940> apply<00:36:57.300> for<00:36:58.079> which<00:36:58.320> problem<00:36:58.619> and 00:36:59.089 --> 00:36:59.099 align:start position:0% you should apply for which problem and 00:36:59.099 --> 00:37:01.130 align:start position:0% you should apply for which problem and for<00:36:59.280> things<00:36:59.520> like<00:36:59.700> Korean<00:37:00.060> transition<00:37:00.420> static 00:37:01.130 --> 00:37:01.140 align:start position:0% for things like Korean transition static 00:37:01.140 --> 00:37:03.470 align:start position:0% for things like Korean transition static analysis<00:37:01.560> is<00:37:02.040> just<00:37:02.280> going<00:37:02.460> to<00:37:02.579> be<00:37:02.700> better 00:37:03.470 --> 00:37:03.480 align:start position:0% analysis is just going to be better 00:37:03.480 --> 00:37:05.329 align:start position:0% analysis is just going to be better you<00:37:03.900> can<00:37:03.960> use<00:37:04.140> further<00:37:04.440> you<00:37:04.740> can<00:37:04.859> create<00:37:05.040> like 00:37:05.329 --> 00:37:05.339 align:start position:0% you can use further you can create like 00:37:05.339 --> 00:37:07.609 align:start position:0% you can use further you can create like random<00:37:05.820> callback<00:37:06.300> and<00:37:06.540> things<00:37:06.720> like<00:37:06.839> that<00:37:07.020> but 00:37:07.609 --> 00:37:07.619 align:start position:0% random callback and things like that but 00:37:07.619 --> 00:37:09.349 align:start position:0% random callback and things like that but in<00:37:07.859> practice<00:37:08.040> static<00:37:08.520> analysis<00:37:08.940> is<00:37:09.119> just 00:37:09.349 --> 00:37:09.359 align:start position:0% in practice static analysis is just 00:37:09.359 --> 00:37:11.270 align:start position:0% in practice static analysis is just going<00:37:09.540> to<00:37:09.660> outperform<00:37:10.260> any<00:37:10.619> further<00:37:10.980> this 00:37:11.270 --> 00:37:11.280 align:start position:0% going to outperform any further this 00:37:11.280 --> 00:37:14.270 align:start position:0% going to outperform any further this work<00:37:11.520> uh<00:37:12.300> that's<00:37:12.420> why<00:37:12.599> like<00:37:12.839> for<00:37:13.020> any<00:37:13.320> any 00:37:14.270 --> 00:37:14.280 align:start position:0% work uh that's why like for any any 00:37:14.280 --> 00:37:16.910 align:start position:0% work uh that's why like for any any class<00:37:14.700> of<00:37:15.000> vulnerability<00:37:15.660> which<00:37:16.440> is<00:37:16.619> kind<00:37:16.800> of 00:37:16.910 --> 00:37:16.920 align:start position:0% class of vulnerability which is kind of 00:37:16.920 --> 00:37:19.250 align:start position:0% class of vulnerability which is kind of a<00:37:17.099> pattern<00:37:17.520> base<00:37:17.820> you<00:37:18.660> can<00:37:18.720> use<00:37:18.839> static 00:37:19.250 --> 00:37:19.260 align:start position:0% a pattern base you can use static 00:37:19.260 --> 00:37:20.810 align:start position:0% a pattern base you can use static analysis<00:37:19.619> and<00:37:19.859> it's<00:37:20.040> going<00:37:20.220> to<00:37:20.339> be<00:37:20.460> better<00:37:20.579> in 00:37:20.810 --> 00:37:20.820 align:start position:0% analysis and it's going to be better in 00:37:20.820 --> 00:37:24.050 align:start position:0% analysis and it's going to be better in my<00:37:20.940> opinion 00:37:24.050 --> 00:37:24.060 align:start position:0% 00:37:24.060 --> 00:37:27.550 align:start position:0% foreign 00:37:27.550 --> 00:37:27.560 align:start position:0% 00:37:27.560 --> 00:37:29.810 align:start position:0% one<00:37:28.560> more<00:37:28.619> question<00:37:28.800> what's<00:37:29.160> your<00:37:29.460> addition 00:37:29.810 --> 00:37:29.820 align:start position:0% one more question what's your addition 00:37:29.820 --> 00:37:32.329 align:start position:0% one more question what's your addition for<00:37:30.119> example<00:37:30.359> we<00:37:30.599> have<00:37:30.780> a<00:37:30.960> complex<00:37:31.200> system 00:37:32.329 --> 00:37:32.339 align:start position:0% for example we have a complex system 00:37:32.339 --> 00:37:35.510 align:start position:0% for example we have a complex system and<00:37:32.940> we<00:37:33.180> want<00:37:33.420> to<00:37:33.599> make<00:37:33.900> a<00:37:34.260> classical<00:37:34.560> fuzzing 00:37:35.510 --> 00:37:35.520 align:start position:0% and we want to make a classical fuzzing 00:37:35.520 --> 00:37:38.569 align:start position:0% and we want to make a classical fuzzing with<00:37:35.700> the<00:37:35.880> kidnap<00:37:36.359> and<00:37:37.260> it<00:37:37.500> seems<00:37:37.859> that<00:37:38.040> to 00:37:38.569 --> 00:37:38.579 align:start position:0% with the kidnap and it seems that to 00:37:38.579 --> 00:37:40.849 align:start position:0% with the kidnap and it seems that to really<00:37:38.820> cover<00:37:39.119> many<00:37:39.599> cases<00:37:39.960> it<00:37:40.260> requires<00:37:40.680> a 00:37:40.849 --> 00:37:40.859 align:start position:0% really cover many cases it requires a 00:37:40.859 --> 00:37:43.849 align:start position:0% really cover many cases it requires a lot<00:37:40.920> of<00:37:41.040> computational<00:37:41.460> power<00:37:42.200> so<00:37:43.200> maybe<00:37:43.500> can 00:37:43.849 --> 00:37:43.859 align:start position:0% lot of computational power so maybe can 00:37:43.859 --> 00:37:46.010 align:start position:0% lot of computational power so maybe can you<00:37:44.040> advise<00:37:44.339> some<00:37:44.579> cloud<00:37:44.760> provider<00:37:45.480> or<00:37:45.660> how<00:37:45.900> to 00:37:46.010 --> 00:37:46.020 align:start position:0% you advise some cloud provider or how to 00:37:46.020 --> 00:37:48.530 align:start position:0% you advise some cloud provider or how to do<00:37:46.200> to<00:37:46.440> run<00:37:46.619> it<00:37:46.800> maybe<00:37:46.980> for<00:37:47.280> a<00:37:47.460> week<00:37:47.640> with<00:37:48.060> very 00:37:48.530 --> 00:37:48.540 align:start position:0% do to run it maybe for a week with very 00:37:48.540 --> 00:37:50.870 align:start position:0% do to run it maybe for a week with very powerful<00:37:48.960> computer<00:37:49.320> to<00:37:50.280> get<00:37:50.460> something 00:37:50.870 --> 00:37:50.880 align:start position:0% powerful computer to get something 00:37:50.880 --> 00:37:53.030 align:start position:0% powerful computer to get something achievable<00:37:51.599> because<00:37:51.900> of<00:37:52.140> course<00:37:52.320> this<00:37:52.619> pretty 00:37:53.030 --> 00:37:53.040 align:start position:0% achievable because of course this pretty 00:37:53.040 --> 00:37:54.650 align:start position:0% achievable because of course this pretty simple<00:37:53.280> contracts<00:37:53.820> could<00:37:54.000> be<00:37:54.119> found<00:37:54.300> on<00:37:54.540> my 00:37:54.650 --> 00:37:54.660 align:start position:0% simple contracts could be found on my 00:37:54.660 --> 00:37:56.630 align:start position:0% simple contracts could be found on my MacBook<00:37:55.020> but<00:37:55.680> if<00:37:55.859> we<00:37:56.040> go<00:37:56.220> a<00:37:56.400> little<00:37:56.460> bit 00:37:56.630 --> 00:37:56.640 align:start position:0% MacBook but if we go a little bit 00:37:56.640 --> 00:37:59.150 align:start position:0% MacBook but if we go a little bit further<00:37:56.940> many<00:37:57.240> contracts<00:37:57.780> many<00:37:57.960> setups<00:37:58.560> maybe 00:37:59.150 --> 00:37:59.160 align:start position:0% further many contracts many setups maybe 00:37:59.160 --> 00:38:03.349 align:start position:0% further many contracts many setups maybe it<00:37:59.400> requires<00:37:59.940> more<00:38:00.240> computational<00:38:00.720> power 00:38:03.349 --> 00:38:03.359 align:start position:0% 00:38:03.359 --> 00:38:04.990 align:start position:0% um<00:38:03.420> so 00:38:04.990 --> 00:38:05.000 align:start position:0% um so 00:38:05.000 --> 00:38:11.150 align:start position:0% um so do<00:38:06.000> you<00:38:06.119> want<00:38:06.180> to<00:38:06.300> talk<00:38:06.420> about<00:38:06.599> the<00:38:06.780> kinapad 00:38:11.150 --> 00:38:11.160 align:start position:0% 00:38:11.160 --> 00:38:13.550 align:start position:0% so<00:38:11.579> the<00:38:11.820> question<00:38:12.000> was<00:38:12.839> um<00:38:12.900> if<00:38:13.200> you<00:38:13.320> want<00:38:13.440> to 00:38:13.550 --> 00:38:13.560 align:start position:0% so the question was um if you want to 00:38:13.560 --> 00:38:15.410 align:start position:0% so the question was um if you want to run<00:38:13.680> a<00:38:13.859> key<00:38:13.980> down<00:38:14.160> the<00:38:14.339> cloud<00:38:14.460> or<00:38:14.820> on<00:38:15.000> a<00:38:15.180> lot<00:38:15.300> of 00:38:15.410 --> 00:38:15.420 align:start position:0% run a key down the cloud or on a lot of 00:38:15.420 --> 00:38:18.170 align:start position:0% run a key down the cloud or on a lot of you<00:38:15.599> know<00:38:15.720> a<00:38:16.099> large<00:38:17.099> like<00:38:17.339> system<00:38:17.579> how<00:38:17.880> can<00:38:18.060> you 00:38:18.170 --> 00:38:18.180 align:start position:0% you know a large like system how can you 00:38:18.180 --> 00:38:20.329 align:start position:0% you know a large like system how can you do<00:38:18.240> it<00:38:18.359> yeah<00:38:18.540> yeah<00:38:18.660> so<00:38:18.960> so<00:38:19.200> so<00:38:19.320> the<00:38:20.040> first<00:38:20.160> thing 00:38:20.329 --> 00:38:20.339 align:start position:0% do it yeah yeah so so so the first thing 00:38:20.339 --> 00:38:25.370 align:start position:0% do it yeah yeah so so so the first thing that<00:38:20.640> uh<00:38:21.240> you<00:38:21.480> should<00:38:21.660> know<00:38:21.839> is<00:38:22.200> that<00:38:22.560> uh 00:38:25.370 --> 00:38:25.380 align:start position:0% 00:38:25.380 --> 00:38:28.250 align:start position:0% uh<00:38:25.440> very<00:38:25.920> large<00:38:26.040> contract<00:38:26.820> it<00:38:27.180> can<00:38:27.300> take<00:38:27.839> some 00:38:28.250 --> 00:38:28.260 align:start position:0% uh very large contract it can take some 00:38:28.260 --> 00:38:30.890 align:start position:0% uh very large contract it can take some amount<00:38:28.560> of<00:38:28.680> memory<00:38:28.980> so<00:38:29.160> first<00:38:30.119> first<00:38:30.599> thing 00:38:30.890 --> 00:38:30.900 align:start position:0% amount of memory so first first thing 00:38:30.900 --> 00:38:33.950 align:start position:0% amount of memory so first first thing get<00:38:31.320> a<00:38:31.500> good<00:38:31.619> server<00:38:32.040> with<00:38:32.640> with<00:38:33.300> a<00:38:33.720> good 00:38:33.950 --> 00:38:33.960 align:start position:0% get a good server with with a good 00:38:33.960 --> 00:38:37.849 align:start position:0% get a good server with with a good amount<00:38:34.260> of<00:38:34.380> of<00:38:34.680> memory<00:38:35.220> and<00:38:35.760> CPUs 00:38:37.849 --> 00:38:37.859 align:start position:0% amount of of memory and CPUs 00:38:37.859 --> 00:38:40.670 align:start position:0% amount of of memory and CPUs um<00:38:37.920> so<00:38:38.280> the<00:38:38.400> second<00:38:38.520> thing<00:38:38.820> is<00:38:39.060> uh<00:38:39.839> every 00:38:40.670 --> 00:38:40.680 align:start position:0% um so the second thing is uh every 00:38:40.680 --> 00:38:43.490 align:start position:0% um so the second thing is uh every um we<00:38:41.160> have<00:38:41.280> a<00:38:41.520> python<00:38:42.180> companion<00:38:43.140> tool 00:38:43.490 --> 00:38:43.500 align:start position:0% um we have a python companion tool 00:38:43.500 --> 00:38:46.609 align:start position:0% um we have a python companion tool called<00:38:43.680> in<00:38:43.980> a<00:38:44.160> parade<00:38:44.400> that<00:38:45.060> will<00:38:45.240> run<00:38:45.619> echina 00:38:46.609 --> 00:38:46.619 align:start position:0% called in a parade that will run echina 00:38:46.619 --> 00:38:50.630 align:start position:0% called in a parade that will run echina in<00:38:47.160> any<00:38:47.460> number<00:38:47.640> of<00:38:47.900> uh<00:38:48.900> any<00:38:49.320> number<00:38:49.500> of<00:38:49.740> uh 00:38:50.630 --> 00:38:50.640 align:start position:0% in any number of uh any number of uh 00:38:50.640 --> 00:38:53.030 align:start position:0% in any number of uh any number of uh concurrent 00:38:53.030 --> 00:38:53.040 align:start position:0% concurrent 00:38:53.040 --> 00:38:56.510 align:start position:0% concurrent um<00:38:53.060> uh<00:38:54.060> instances<00:38:54.660> so<00:38:55.079> you<00:38:55.320> can<00:38:55.440> run<00:38:55.740> 10<00:38:56.099> at<00:38:56.339> a 00:38:56.510 --> 00:38:56.520 align:start position:0% um uh instances so you can run 10 at a 00:38:56.520 --> 00:39:00.050 align:start position:0% um uh instances so you can run 10 at a time<00:38:57.020> uh<00:38:58.020> but<00:38:58.560> we're<00:38:58.859> not<00:38:59.099> only<00:38:59.280> going<00:38:59.640> to<00:38:59.880> run 00:39:00.050 --> 00:39:00.060 align:start position:0% time uh but we're not only going to run 00:39:00.060 --> 00:39:02.050 align:start position:0% time uh but we're not only going to run it<00:39:00.300> 10<00:39:00.480> of<00:39:00.720> the<00:39:00.839> time<00:39:00.960> but<00:39:01.260> we<00:39:01.560> are<00:39:01.740> going<00:39:01.859> to 00:39:02.050 --> 00:39:02.060 align:start position:0% it 10 of the time but we are going to 00:39:02.060 --> 00:39:05.569 align:start position:0% it 10 of the time but we are going to randomly<00:39:03.060> Shuffle<00:39:03.300> parameters<00:39:04.020> because<00:39:04.920> in 00:39:05.569 --> 00:39:05.579 align:start position:0% randomly Shuffle parameters because in 00:39:05.579 --> 00:39:08.089 align:start position:0% randomly Shuffle parameters because in some<00:39:05.760> cases<00:39:06.119> there<00:39:06.660> are<00:39:06.839> some<00:39:07.020> there<00:39:07.740> are<00:39:07.859> some 00:39:08.089 --> 00:39:08.099 align:start position:0% some cases there are some there are some 00:39:08.099 --> 00:39:11.089 align:start position:0% some cases there are some there are some issues<00:39:08.520> that<00:39:08.820> can<00:39:09.000> be<00:39:09.240> easily<00:39:09.900> found<00:39:10.140> with 00:39:11.089 --> 00:39:11.099 align:start position:0% issues that can be easily found with 00:39:11.099 --> 00:39:14.089 align:start position:0% issues that can be easily found with let's<00:39:11.400> say<00:39:11.579> three<00:39:12.000> or<00:39:12.300> ten<00:39:12.720> transactions<00:39:13.380> and 00:39:14.089 --> 00:39:14.099 align:start position:0% let's say three or ten transactions and 00:39:14.099 --> 00:39:16.730 align:start position:0% let's say three or ten transactions and some<00:39:14.400> other<00:39:14.960> issues<00:39:15.960> are<00:39:16.140> going<00:39:16.320> to<00:39:16.440> be<00:39:16.560> more 00:39:16.730 --> 00:39:16.740 align:start position:0% some other issues are going to be more 00:39:16.740 --> 00:39:19.730 align:start position:0% some other issues are going to be more easily<00:39:16.980> found<00:39:17.280> with<00:39:17.700> two<00:39:18.540> 200<00:39:19.020> transactions 00:39:19.730 --> 00:39:19.740 align:start position:0% easily found with two 200 transactions 00:39:19.740 --> 00:39:23.030 align:start position:0% easily found with two 200 transactions in<00:39:20.220> a<00:39:20.400> in<00:39:20.640> a<00:39:20.880> in<00:39:21.119> a<00:39:21.300> row<00:39:21.540> right<00:39:22.079> so<00:39:22.380> what<00:39:22.680> we<00:39:22.800> do 00:39:23.030 --> 00:39:23.040 align:start position:0% in a in a in a row right so what we do 00:39:23.040 --> 00:39:25.430 align:start position:0% in a in a in a row right so what we do is<00:39:23.160> we<00:39:23.520> run<00:39:23.700> the<00:39:23.940> tool<00:39:24.240> in<00:39:24.960> different<00:39:25.140> with 00:39:25.430 --> 00:39:25.440 align:start position:0% is we run the tool in different with 00:39:25.440 --> 00:39:27.589 align:start position:0% is we run the tool in different with different<00:39:25.680> random<00:39:26.220> parameters<00:39:26.760> and<00:39:27.420> in 00:39:27.589 --> 00:39:27.599 align:start position:0% different random parameters and in 00:39:27.599 --> 00:39:30.650 align:start position:0% different random parameters and in different<00:39:27.780> let's<00:39:28.740> say<00:39:28.980> Generations<00:39:29.579> so<00:39:30.240> we 00:39:30.650 --> 00:39:30.660 align:start position:0% different let's say Generations so we 00:39:30.660 --> 00:39:33.410 align:start position:0% different let's say Generations so we run<00:39:30.900> we<00:39:31.440> run<00:39:31.619> akina<00:39:31.980> for<00:39:32.220> an<00:39:32.339> hour<00:39:32.520> 10<00:39:33.180> times 00:39:33.410 --> 00:39:33.420 align:start position:0% run we run akina for an hour 10 times 00:39:33.420 --> 00:39:36.890 align:start position:0% run we run akina for an hour 10 times then<00:39:34.320> we<00:39:34.560> save<00:39:34.740> the<00:39:34.980> Corpus<00:39:35.400> and<00:39:36.060> you<00:39:36.240> can<00:39:36.359> get 00:39:36.890 --> 00:39:36.900 align:start position:0% then we save the Corpus and you can get 00:39:36.900 --> 00:39:39.710 align:start position:0% then we save the Corpus and you can get you<00:39:37.500> you<00:39:37.740> can<00:39:37.920> see<00:39:38.160> all<00:39:38.339> the<00:39:38.640> all<00:39:39.119> the<00:39:39.300> all<00:39:39.599> the 00:39:39.710 --> 00:39:39.720 align:start position:0% you you can see all the all the all the 00:39:39.720 --> 00:39:41.270 align:start position:0% you you can see all the all the all the code<00:39:39.839> that<00:39:40.079> was<00:39:40.200> covered<00:39:40.619> and<00:39:40.980> then<00:39:41.099> we 00:39:41.270 --> 00:39:41.280 align:start position:0% code that was covered and then we 00:39:41.280 --> 00:39:44.210 align:start position:0% code that was covered and then we started<00:39:41.640> again<00:39:41.760> but<00:39:42.240> taking<00:39:42.800> the<00:39:43.800> the<00:39:44.099> the 00:39:44.210 --> 00:39:44.220 align:start position:0% started again but taking the the the 00:39:44.220 --> 00:39:46.730 align:start position:0% started again but taking the the the output<00:39:44.820> of<00:39:45.060> the<00:39:45.240> previous<00:39:45.359> generation<00:39:45.960> so<00:39:46.500> you 00:39:46.730 --> 00:39:46.740 align:start position:0% output of the previous generation so you 00:39:46.740 --> 00:39:48.530 align:start position:0% output of the previous generation so you iterate<00:39:47.220> over<00:39:47.339> and<00:39:47.520> over<00:39:47.700> again<00:39:47.880> so<00:39:48.119> you<00:39:48.359> can 00:39:48.530 --> 00:39:48.540 align:start position:0% iterate over and over again so you can 00:39:48.540 --> 00:39:52.130 align:start position:0% iterate over and over again so you can see<00:39:48.839> how<00:39:49.500> your<00:39:49.740> code<00:39:49.920> is<00:39:50.160> explored<00:39:51.240> right<00:39:51.720> or 00:39:52.130 --> 00:39:52.140 align:start position:0% see how your code is explored right or 00:39:52.140 --> 00:39:53.930 align:start position:0% see how your code is explored right or if<00:39:52.380> there's<00:39:52.619> some<00:39:52.980> part<00:39:53.220> of<00:39:53.400> the<00:39:53.460> code<00:39:53.579> that<00:39:53.820> is 00:39:53.930 --> 00:39:53.940 align:start position:0% if there's some part of the code that is 00:39:53.940 --> 00:39:56.450 align:start position:0% if there's some part of the code that is not<00:39:54.119> explored<00:39:54.599> with<00:39:54.900> 10<00:39:55.140> different<00:39:55.460> uh 00:39:56.450 --> 00:39:56.460 align:start position:0% not explored with 10 different uh 00:39:56.460 --> 00:39:58.310 align:start position:0% not explored with 10 different uh instances<00:39:56.880> you<00:39:57.300> can<00:39:57.420> go<00:39:57.599> back<00:39:57.720> and<00:39:57.900> say<00:39:58.020> no<00:39:58.200> I 00:39:58.310 --> 00:39:58.320 align:start position:0% instances you can go back and say no I 00:39:58.320 --> 00:39:59.810 align:start position:0% instances you can go back and say no I need<00:39:58.440> I<00:39:58.680> need<00:39:58.800> to<00:39:58.920> change<00:39:59.099> this<00:39:59.339> because<00:39:59.579> it 00:39:59.810 --> 00:39:59.820 align:start position:0% need I need to change this because it 00:39:59.820 --> 00:40:01.849 align:start position:0% need I need to change this because it doesn't<00:40:00.000> depend<00:40:00.480> on<00:40:00.660> the<00:40:00.960> on<00:40:01.440> the<00:40:01.619> actual 00:40:01.849 --> 00:40:01.859 align:start position:0% doesn't depend on the on the actual 00:40:01.859 --> 00:40:05.210 align:start position:0% doesn't depend on the on the actual execution<00:40:02.420> so<00:40:03.420> we<00:40:03.780> can<00:40:03.960> we<00:40:04.260> can<00:40:04.440> give<00:40:04.920> you<00:40:05.099> the 00:40:05.210 --> 00:40:05.220 align:start position:0% execution so we can we can give you the 00:40:05.220 --> 00:40:07.910 align:start position:0% execution so we can we can give you the link<00:40:05.460> uh<00:40:06.300> for<00:40:06.540> that<00:40:06.660> it's<00:40:06.900> just<00:40:07.200> a<00:40:07.380> python<00:40:07.680> tool 00:40:07.910 --> 00:40:07.920 align:start position:0% link uh for that it's just a python tool 00:40:07.920 --> 00:40:09.950 align:start position:0% link uh for that it's just a python tool so<00:40:08.040> it's<00:40:08.220> it's<00:40:08.520> it's<00:40:08.700> easy<00:40:09.180> to<00:40:09.359> use<00:40:09.780> um<00:40:09.839> yeah 00:40:09.950 --> 00:40:09.960 align:start position:0% so it's it's it's easy to use um yeah 00:40:09.960 --> 00:40:11.329 align:start position:0% so it's it's it's easy to use um yeah it's<00:40:10.079> also<00:40:10.320> open<00:40:10.440> source<00:40:10.740> like<00:40:10.859> everything<00:40:11.040> we 00:40:11.329 --> 00:40:11.339 align:start position:0% it's also open source like everything we 00:40:11.339 --> 00:40:15.250 align:start position:0% it's also open source like everything we are<00:40:11.520> doing<00:40:11.640> is<00:40:11.820> open<00:40:12.000> source 00:40:15.250 --> 00:40:15.260 align:start position:0% 00:40:15.260 --> 00:40:17.870 align:start position:0% okay<00:40:16.260> so<00:40:16.500> yeah<00:40:16.680> like<00:40:17.040> it's<00:40:17.339> really<00:40:17.579> about 00:40:17.870 --> 00:40:17.880 align:start position:0% okay so yeah like it's really about 00:40:17.880 --> 00:40:19.790 align:start position:0% okay so yeah like it's really about spending<00:40:18.720> time<00:40:18.900> and<00:40:19.079> thinking<00:40:19.380> about<00:40:19.500> our 00:40:19.790 --> 00:40:19.800 align:start position:0% spending time and thinking about our 00:40:19.800 --> 00:40:21.410 align:start position:0% spending time and thinking about our invariants 00:40:21.410 --> 00:40:21.420 align:start position:0% invariants 00:40:21.420 --> 00:40:23.210 align:start position:0% invariants and<00:40:21.839> it's<00:40:21.960> not<00:40:22.079> simple<00:40:22.260> like<00:40:22.560> it's<00:40:22.800> the<00:40:23.040> first 00:40:23.210 --> 00:40:23.220 align:start position:0% and it's not simple like it's the first 00:40:23.220 --> 00:40:26.030 align:start position:0% and it's not simple like it's the first invariant<00:40:23.940> that<00:40:24.180> you<00:40:24.300> are<00:40:24.480> writing<00:40:24.960> leads<00:40:25.920> to 00:40:26.030 --> 00:40:26.040 align:start position:0% invariant that you are writing leads to 00:40:26.040 --> 00:40:28.130 align:start position:0% invariant that you are writing leads to a<00:40:26.220> bugs<00:40:26.579> there<00:40:27.180> is<00:40:27.359> something<00:40:27.599> wrong<00:40:27.839> about 00:40:28.130 --> 00:40:28.140 align:start position:0% a bugs there is something wrong about 00:40:28.140 --> 00:40:30.710 align:start position:0% a bugs there is something wrong about your<00:40:28.380> approach<00:40:28.760> uh<00:40:29.760> you<00:40:30.300> should<00:40:30.420> not<00:40:30.599> have 00:40:30.710 --> 00:40:30.720 align:start position:0% your approach uh you should not have 00:40:30.720 --> 00:40:32.210 align:start position:0% your approach uh you should not have like<00:40:30.960> simple<00:40:31.140> invariants<00:40:31.680> that<00:40:31.859> you<00:40:31.980> know<00:40:32.099> are 00:40:32.210 --> 00:40:32.220 align:start position:0% like simple invariants that you know are 00:40:32.220 --> 00:40:33.950 align:start position:0% like simple invariants that you know are going<00:40:32.339> to<00:40:32.460> work<00:40:32.640> the<00:40:32.880> system<00:40:33.000> so<00:40:33.480> we'll<00:40:33.720> start 00:40:33.950 --> 00:40:33.960 align:start position:0% going to work the system so we'll start 00:40:33.960 --> 00:40:37.550 align:start position:0% going to work the system so we'll start simple<00:40:34.200> and<00:40:34.560> iterate<00:40:34.980> over<00:40:35.220> them 00:40:37.550 --> 00:40:37.560 align:start position:0% 00:40:37.560 --> 00:40:39.829 align:start position:0% okay<00:40:37.859> to<00:40:38.099> give<00:40:38.220> you<00:40:38.339> some<00:40:38.520> example<00:40:38.940> let's<00:40:39.660> say 00:40:39.829 --> 00:40:39.839 align:start position:0% okay to give you some example let's say 00:40:39.839 --> 00:40:42.410 align:start position:0% okay to give you some example let's say you<00:40:40.200> have<00:40:40.380> a<00:40:40.500> now<00:40:40.619> with<00:40:40.740> magic<00:40:40.980> libraries<00:40:41.640> what 00:40:42.410 --> 00:40:42.420 align:start position:0% you have a now with magic libraries what 00:40:42.420 --> 00:40:43.970 align:start position:0% you have a now with magic libraries what environment<00:40:42.839> can<00:40:43.020> you<00:40:43.200> have 00:40:43.970 --> 00:40:43.980 align:start position:0% environment can you have 00:40:43.980 --> 00:40:45.950 align:start position:0% environment can you have um<00:40:44.040> you<00:40:44.339> can<00:40:44.400> have<00:40:44.520> commutative<00:40:45.000> properties<00:40:45.599> a 00:40:45.950 --> 00:40:45.960 align:start position:0% um you can have commutative properties a 00:40:45.960 --> 00:40:48.770 align:start position:0% um you can have commutative properties a plus<00:40:46.200> b<00:40:46.440> is<00:40:46.740> equal<00:40:46.920> to<00:40:47.160> B<00:40:47.400> plus<00:40:47.640> a<00:40:47.940> you<00:40:48.480> can<00:40:48.660> have 00:40:48.770 --> 00:40:48.780 align:start position:0% plus b is equal to B plus a you can have 00:40:48.780 --> 00:40:52.370 align:start position:0% plus b is equal to B plus a you can have identity<00:40:49.500> a<00:40:50.400> one<00:40:51.000> multiplied<00:40:51.480> by<00:40:51.780> two<00:40:51.960> should 00:40:52.370 --> 00:40:52.380 align:start position:0% identity a one multiplied by two should 00:40:52.380 --> 00:40:55.069 align:start position:0% identity a one multiplied by two should be<00:40:52.619> true<00:40:53.220> our<00:40:53.760> inverse<00:40:54.240> if<00:40:54.420> you<00:40:54.599> add<00:40:54.839> something 00:40:55.069 --> 00:40:55.079 align:start position:0% be true our inverse if you add something 00:40:55.079 --> 00:40:57.589 align:start position:0% be true our inverse if you add something by<00:40:55.440> its<00:40:55.619> opposite<00:40:56.099> it<00:40:56.339> should<00:40:56.520> be<00:40:56.640> zero<00:40:57.000> this 00:40:57.589 --> 00:40:57.599 align:start position:0% by its opposite it should be zero this 00:40:57.599 --> 00:40:59.150 align:start position:0% by its opposite it should be zero this is<00:40:57.660> not<00:40:57.839> always<00:40:57.960> true<00:40:58.260> right<00:40:58.500> but<00:40:58.740> depending 00:40:59.150 --> 00:40:59.160 align:start position:0% is not always true right but depending 00:40:59.160 --> 00:41:00.589 align:start position:0% is not always true right but depending of<00:40:59.280> what<00:40:59.520> you<00:40:59.700> are<00:40:59.820> building<00:40:59.940> this<00:41:00.240> might<00:41:00.420> be 00:41:00.589 --> 00:41:00.599 align:start position:0% of what you are building this might be 00:41:00.599 --> 00:41:01.849 align:start position:0% of what you are building this might be like<00:41:00.780> the<00:41:00.900> type<00:41:01.079> of<00:41:01.200> property<00:41:01.500> you<00:41:01.740> are 00:41:01.849 --> 00:41:01.859 align:start position:0% like the type of property you are 00:41:01.859 --> 00:41:03.770 align:start position:0% like the type of property you are looking<00:41:02.040> for 00:41:03.770 --> 00:41:03.780 align:start position:0% looking for 00:41:03.780 --> 00:41:05.990 align:start position:0% looking for for<00:41:04.260> token<00:41:04.800> we<00:41:05.160> already<00:41:05.339> talked<00:41:05.700> about<00:41:05.760> the 00:41:05.990 --> 00:41:06.000 align:start position:0% for token we already talked about the 00:41:06.000 --> 00:41:07.670 align:start position:0% for token we already talked about the first<00:41:06.119> one<00:41:06.300> no<00:41:06.599> no<00:41:06.839> user<00:41:07.200> should<00:41:07.380> have<00:41:07.500> a 00:41:07.670 --> 00:41:07.680 align:start position:0% first one no no user should have a 00:41:07.680 --> 00:41:08.930 align:start position:0% first one no no user should have a balance<00:41:07.980> above 00:41:08.930 --> 00:41:08.940 align:start position:0% balance above 00:41:08.940 --> 00:41:11.329 align:start position:0% balance above total<00:41:09.540> Supply<00:41:09.720> let's<00:41:10.680> say<00:41:10.800> you<00:41:10.980> want<00:41:11.099> to<00:41:11.220> look 00:41:11.329 --> 00:41:11.339 align:start position:0% total Supply let's say you want to look 00:41:11.339 --> 00:41:13.849 align:start position:0% total Supply let's say you want to look at<00:41:11.520> the<00:41:11.640> transfer<00:41:12.060> function<00:41:12.359> and<00:41:12.960> patsync 00:41:13.849 --> 00:41:13.859 align:start position:0% at the transfer function and patsync 00:41:13.859 --> 00:41:15.650 align:start position:0% at the transfer function and patsync transfer<00:41:14.220> function<00:41:14.460> what<00:41:14.700> does<00:41:14.880> it<00:41:15.000> do 00:41:15.650 --> 00:41:15.660 align:start position:0% transfer function what does it do 00:41:15.660 --> 00:41:18.170 align:start position:0% transfer function what does it do I'm<00:41:16.079> transferring<00:41:16.740> token<00:41:17.040> to<00:41:17.400> someone<00:41:17.579> so<00:41:17.940> at 00:41:18.170 --> 00:41:18.180 align:start position:0% I'm transferring token to someone so at 00:41:18.180 --> 00:41:20.630 align:start position:0% I'm transferring token to someone so at the<00:41:18.359> end<00:41:18.540> my<00:41:19.200> balance<00:41:19.619> should<00:41:19.920> have<00:41:20.099> decreased 00:41:20.630 --> 00:41:20.640 align:start position:0% the end my balance should have decreased 00:41:20.640 --> 00:41:22.910 align:start position:0% the end my balance should have decreased by<00:41:20.820> the<00:41:21.000> amount<00:41:21.180> and<00:41:21.900> the<00:41:22.079> receiver<00:41:22.440> should 00:41:22.910 --> 00:41:22.920 align:start position:0% by the amount and the receiver should 00:41:22.920 --> 00:41:25.670 align:start position:0% by the amount and the receiver should have<00:41:23.099> see<00:41:23.760> uh<00:41:24.240> its<00:41:24.599> balance<00:41:24.839> increased<00:41:25.440> by<00:41:25.560> the 00:41:25.670 --> 00:41:25.680 align:start position:0% have see uh its balance increased by the 00:41:25.680 --> 00:41:27.950 align:start position:0% have see uh its balance increased by the amount<00:41:26.460> and<00:41:26.940> let's<00:41:27.060> say<00:41:27.240> you<00:41:27.480> try<00:41:27.660> to<00:41:27.780> write 00:41:27.950 --> 00:41:27.960 align:start position:0% amount and let's say you try to write 00:41:27.960 --> 00:41:29.510 align:start position:0% amount and let's say you try to write something<00:41:28.200> like<00:41:28.500> that 00:41:29.510 --> 00:41:29.520 align:start position:0% something like that 00:41:29.520 --> 00:41:32.450 align:start position:0% something like that once<00:41:30.119> you<00:41:30.240> might<00:41:30.420> quickly<00:41:30.780> realized<00:41:31.460> that 00:41:32.450 --> 00:41:32.460 align:start position:0% once you might quickly realized that 00:41:32.460 --> 00:41:35.089 align:start position:0% once you might quickly realized that what<00:41:32.820> happened<00:41:33.000> if<00:41:33.420> the<00:41:33.599> destination<00:41:34.099> is 00:41:35.089 --> 00:41:35.099 align:start position:0% what happened if the destination is 00:41:35.099 --> 00:41:38.150 align:start position:0% what happened if the destination is myself<00:41:35.820> so<00:41:36.599> if<00:41:36.720> I<00:41:36.960> transfer<00:41:37.380> token<00:41:37.800> to<00:41:37.980> myself 00:41:38.150 --> 00:41:38.160 align:start position:0% myself so if I transfer token to myself 00:41:38.160 --> 00:41:40.849 align:start position:0% myself so if I transfer token to myself my<00:41:39.119> balance<00:41:39.420> is<00:41:39.599> not<00:41:39.780> going<00:41:39.960> to<00:41:40.079> increase<00:41:40.500> or 00:41:40.849 --> 00:41:40.859 align:start position:0% my balance is not going to increase or 00:41:40.859 --> 00:41:43.130 align:start position:0% my balance is not going to increase or decrease<00:41:41.040> quite<00:41:41.700> awfully<00:41:42.119> so<00:41:42.780> this<00:41:42.900> is<00:41:42.960> an 00:41:43.130 --> 00:41:43.140 align:start position:0% decrease quite awfully so this is an 00:41:43.140 --> 00:41:44.870 align:start position:0% decrease quite awfully so this is an example<00:41:43.380> where<00:41:43.740> you<00:41:44.099> might<00:41:44.220> try<00:41:44.339> to<00:41:44.460> Define<00:41:44.640> an 00:41:44.870 --> 00:41:44.880 align:start position:0% example where you might try to Define an 00:41:44.880 --> 00:41:46.670 align:start position:0% example where you might try to Define an invariance<00:41:45.359> on<00:41:45.660> transfer<00:41:46.079> it<00:41:46.260> might<00:41:46.380> seem 00:41:46.670 --> 00:41:46.680 align:start position:0% invariance on transfer it might seem 00:41:46.680 --> 00:41:48.650 align:start position:0% invariance on transfer it might seem simple<00:41:46.920> you<00:41:47.579> might<00:41:47.760> write<00:41:48.000> like<00:41:48.240> the<00:41:48.480> the 00:41:48.650 --> 00:41:48.660 align:start position:0% simple you might write like the the 00:41:48.660 --> 00:41:51.050 align:start position:0% simple you might write like the the thing<00:41:48.900> in<00:41:49.020> solidity<00:41:49.560> and<00:41:50.400> if<00:41:50.700> you<00:41:50.820> do<00:41:50.940> that 00:41:51.050 --> 00:41:51.060 align:start position:0% thing in solidity and if you do that 00:41:51.060 --> 00:41:52.370 align:start position:0% thing in solidity and if you do that again<00:41:51.240> is<00:41:51.480> going<00:41:51.660> to<00:41:51.720> tell<00:41:51.839> you<00:41:51.960> that<00:41:52.140> there<00:41:52.260> is 00:41:52.370 --> 00:41:52.380 align:start position:0% again is going to tell you that there is 00:41:52.380 --> 00:41:53.990 align:start position:0% again is going to tell you that there is an<00:41:52.500> edge<00:41:52.619> case<00:41:52.859> where<00:41:53.220> if<00:41:53.400> you<00:41:53.520> transfer<00:41:53.820> to 00:41:53.990 --> 00:41:54.000 align:start position:0% an edge case where if you transfer to 00:41:54.000 --> 00:41:56.510 align:start position:0% an edge case where if you transfer to yourself<00:41:54.500> like<00:41:55.500> the<00:41:55.680> event<00:41:55.859> is<00:41:56.040> going<00:41:56.160> to<00:41:56.400> be 00:41:56.510 --> 00:41:56.520 align:start position:0% yourself like the event is going to be 00:41:56.520 --> 00:41:57.710 align:start position:0% yourself like the event is going to be to<00:41:56.700> be<00:41:56.820> broken 00:41:57.710 --> 00:41:57.720 align:start position:0% to be broken 00:41:57.720 --> 00:41:59.630 align:start position:0% to be broken and<00:41:58.320> in<00:41:58.500> this<00:41:58.619> example<00:41:58.920> if<00:41:59.160> you<00:41:59.339> go<00:41:59.460> through 00:41:59.630 --> 00:41:59.640 align:start position:0% and in this example if you go through 00:41:59.640 --> 00:42:01.250 align:start position:0% and in this example if you go through this<00:42:00.540> um 00:42:01.250 --> 00:42:01.260 align:start position:0% this um 00:42:01.260 --> 00:42:03.230 align:start position:0% this um it's<00:42:01.740> not<00:42:01.859> the<00:42:01.980> code<00:42:02.160> which<00:42:02.640> is<00:42:02.760> bad<00:42:02.880> it's<00:42:03.060> an 00:42:03.230 --> 00:42:03.240 align:start position:0% it's not the code which is bad it's an 00:42:03.240 --> 00:42:04.609 align:start position:0% it's not the code which is bad it's an invariant<00:42:03.599> that<00:42:03.720> was<00:42:03.839> bad<00:42:04.020> so<00:42:04.200> that's<00:42:04.440> why 00:42:04.609 --> 00:42:04.619 align:start position:0% invariant that was bad so that's why 00:42:04.619 --> 00:42:06.950 align:start position:0% invariant that was bad so that's why having<00:42:04.859> this<00:42:05.040> iterative<00:42:05.520> approach<00:42:06.000> uh<00:42:06.780> is 00:42:06.950 --> 00:42:06.960 align:start position:0% having this iterative approach uh is 00:42:06.960 --> 00:42:08.270 align:start position:0% having this iterative approach uh is really<00:42:07.140> important<00:42:07.440> because<00:42:07.680> sometimes<00:42:08.099> we 00:42:08.270 --> 00:42:08.280 align:start position:0% really important because sometimes we 00:42:08.280 --> 00:42:09.470 align:start position:0% really important because sometimes we are<00:42:08.400> going<00:42:08.460> to<00:42:08.579> make<00:42:08.700> assumption<00:42:09.119> about<00:42:09.300> your 00:42:09.470 --> 00:42:09.480 align:start position:0% are going to make assumption about your 00:42:09.480 --> 00:42:11.270 align:start position:0% are going to make assumption about your system<00:42:09.720> and<00:42:10.380> you<00:42:10.560> might<00:42:10.680> actually<00:42:10.859> be<00:42:11.099> wrong 00:42:11.270 --> 00:42:11.280 align:start position:0% system and you might actually be wrong 00:42:11.280 --> 00:42:14.569 align:start position:0% system and you might actually be wrong and<00:42:11.940> as<00:42:12.599> the<00:42:13.079> system<00:42:13.200> gain<00:42:13.920> on<00:42:14.040> complexity 00:42:14.569 --> 00:42:14.579 align:start position:0% and as the system gain on complexity 00:42:14.579 --> 00:42:15.890 align:start position:0% and as the system gain on complexity it's<00:42:14.940> more<00:42:15.119> and<00:42:15.300> more<00:42:15.420> likely<00:42:15.599> that<00:42:15.720> it's 00:42:15.890 --> 00:42:15.900 align:start position:0% it's more and more likely that it's 00:42:15.900 --> 00:42:18.109 align:start position:0% it's more and more likely that it's going<00:42:16.079> to<00:42:16.140> be<00:42:16.260> more<00:42:16.500> difficult<00:42:16.920> to<00:42:17.520> refine<00:42:17.940> the 00:42:18.109 --> 00:42:18.119 align:start position:0% going to be more difficult to refine the 00:42:18.119 --> 00:42:20.750 align:start position:0% going to be more difficult to refine the invariance 00:42:20.750 --> 00:42:20.760 align:start position:0% 00:42:20.760 --> 00:42:22.370 align:start position:0% something<00:42:21.180> else<00:42:21.420> which<00:42:21.599> is<00:42:21.780> also<00:42:22.020> important 00:42:22.370 --> 00:42:22.380 align:start position:0% something else which is also important 00:42:22.380 --> 00:42:25.310 align:start position:0% something else which is also important to<00:42:22.619> to<00:42:22.980> consider<00:42:23.520> is 00:42:25.310 --> 00:42:25.320 align:start position:0% to to consider is 00:42:25.320 --> 00:42:28.490 align:start position:0% to to consider is um<00:42:25.460> patterning<00:42:26.460> first<00:42:26.640> uh<00:42:27.359> reverting<00:42:27.900> for 00:42:28.490 --> 00:42:28.500 align:start position:0% um patterning first uh reverting for 00:42:28.500 --> 00:42:29.930 align:start position:0% um patterning first uh reverting for example<00:42:28.680> an<00:42:28.920> environment<00:42:29.280> you<00:42:29.460> can<00:42:29.579> have<00:42:29.700> is 00:42:29.930 --> 00:42:29.940 align:start position:0% example an environment you can have is 00:42:29.940 --> 00:42:31.670 align:start position:0% example an environment you can have is that<00:42:30.060> if<00:42:30.240> you<00:42:30.359> don't<00:42:30.480> have<00:42:30.660> enough<00:42:30.780> phones<00:42:31.320> the 00:42:31.670 --> 00:42:31.680 align:start position:0% that if you don't have enough phones the 00:42:31.680 --> 00:42:34.670 align:start position:0% that if you don't have enough phones the transfer<00:42:32.160> function<00:42:32.400> to<00:42:32.760> the<00:42:32.940> revert<00:42:33.720> or<00:42:34.320> a 00:42:34.670 --> 00:42:34.680 align:start position:0% transfer function to the revert or a 00:42:34.680 --> 00:42:36.230 align:start position:0% transfer function to the revert or a return<00:42:34.859> first<00:42:35.160> depending<00:42:35.640> on<00:42:35.700> how<00:42:36.060> you 00:42:36.230 --> 00:42:36.240 align:start position:0% return first depending on how you 00:42:36.240 --> 00:42:39.609 align:start position:0% return first depending on how you implemented<00:42:36.660> the<00:42:36.780> token 00:42:39.609 --> 00:42:39.619 align:start position:0% 00:42:39.619 --> 00:42:42.710 align:start position:0% once<00:42:40.619> you<00:42:40.740> have<00:42:40.859> this<00:42:41.040> list<00:42:41.280> of<00:42:41.520> invariants 00:42:42.710 --> 00:42:42.720 align:start position:0% once you have this list of invariants 00:42:42.720 --> 00:42:46.490 align:start position:0% once you have this list of invariants usually<00:42:43.500> you<00:42:44.040> can<00:42:44.220> split<00:42:45.000> invariant<00:42:45.960> into<00:42:46.140> two 00:42:46.490 --> 00:42:46.500 align:start position:0% usually you can split invariant into two 00:42:46.500 --> 00:42:48.950 align:start position:0% usually you can split invariant into two categories<00:42:47.520> function<00:42:48.119> level<00:42:48.300> invariant 00:42:48.950 --> 00:42:48.960 align:start position:0% categories function level invariant 00:42:48.960 --> 00:42:51.890 align:start position:0% categories function level invariant system<00:42:49.800> level<00:42:50.160> invariant<00:42:51.119> function<00:42:51.660> over 00:42:51.890 --> 00:42:51.900 align:start position:0% system level invariant function over 00:42:51.900 --> 00:42:54.290 align:start position:0% system level invariant function over invariant<00:42:52.500> are<00:42:52.800> usually<00:42:53.099> stateless 00:42:54.290 --> 00:42:54.300 align:start position:0% invariant are usually stateless 00:42:54.300 --> 00:42:56.089 align:start position:0% invariant are usually stateless they<00:42:54.839> are<00:42:54.960> things<00:42:55.140> that<00:42:55.380> you<00:42:55.500> can<00:42:55.680> just<00:42:55.920> you 00:42:56.089 --> 00:42:56.099 align:start position:0% they are things that you can just you 00:42:56.099 --> 00:42:57.890 align:start position:0% they are things that you can just you know<00:42:56.220> look<00:42:56.460> at<00:42:56.579> a<00:42:56.760> specific<00:42:57.060> function<00:42:57.420> and<00:42:57.780> try 00:42:57.890 --> 00:42:57.900 align:start position:0% know look at a specific function and try 00:42:57.900 --> 00:43:00.050 align:start position:0% know look at a specific function and try to<00:42:58.079> see<00:42:58.200> if<00:42:58.319> it<00:42:58.500> holds<00:42:58.859> so<00:42:59.160> it<00:42:59.520> may<00:42:59.700> take<00:42:59.880> you 00:43:00.050 --> 00:43:00.060 align:start position:0% to see if it holds so it may take you 00:43:00.060 --> 00:43:01.250 align:start position:0% to see if it holds so it may take you know<00:43:00.119> environment<00:43:00.540> I<00:43:00.720> mentioned<00:43:01.020> are 00:43:01.250 --> 00:43:01.260 align:start position:0% know environment I mentioned are 00:43:01.260 --> 00:43:02.870 align:start position:0% know environment I mentioned are stateless<00:43:01.680> and<00:43:02.040> our<00:43:02.160> functional<00:43:02.520> leveling 00:43:02.870 --> 00:43:02.880 align:start position:0% stateless and our functional leveling 00:43:02.880 --> 00:43:03.890 align:start position:0% stateless and our functional leveling variants 00:43:03.890 --> 00:43:03.900 align:start position:0% variants 00:43:03.900 --> 00:43:06.290 align:start position:0% variants here<00:43:04.440> you<00:43:04.680> can<00:43:04.859> craft<00:43:05.099> simple<00:43:05.460> scenario<00:43:06.060> just 00:43:06.290 --> 00:43:06.300 align:start position:0% here you can craft simple scenario just 00:43:06.300 --> 00:43:08.210 align:start position:0% here you can craft simple scenario just by<00:43:06.420> calling<00:43:06.780> the<00:43:06.900> specific<00:43:07.260> function 00:43:08.210 --> 00:43:08.220 align:start position:0% by calling the specific function 00:43:08.220 --> 00:43:10.250 align:start position:0% by calling the specific function then<00:43:08.880> you<00:43:09.119> have<00:43:09.300> system<00:43:09.540> level<00:43:09.839> in<00:43:10.140> there 00:43:10.250 --> 00:43:10.260 align:start position:0% then you have system level in there 00:43:10.260 --> 00:43:12.470 align:start position:0% then you have system level in there system<00:43:10.980> level<00:43:11.339> environments<00:43:12.000> are<00:43:12.180> usually 00:43:12.470 --> 00:43:12.480 align:start position:0% system level environments are usually 00:43:12.480 --> 00:43:15.050 align:start position:0% system level environments are usually more<00:43:12.839> complex<00:43:13.280> but<00:43:14.280> they're<00:43:14.579> also<00:43:14.880> more 00:43:15.050 --> 00:43:15.060 align:start position:0% more complex but they're also more 00:43:15.060 --> 00:43:17.329 align:start position:0% more complex but they're also more powerful<00:43:15.599> and<00:43:16.140> here<00:43:16.440> you<00:43:16.619> are<00:43:16.740> stateful<00:43:17.099> you 00:43:17.329 --> 00:43:17.339 align:start position:0% powerful and here you are stateful you 00:43:17.339 --> 00:43:19.309 align:start position:0% powerful and here you are stateful you are<00:43:17.520> going<00:43:17.579> to<00:43:17.760> change<00:43:18.060> the<00:43:18.839> state<00:43:18.960> of<00:43:19.200> the 00:43:19.309 --> 00:43:19.319 align:start position:0% are going to change the state of the 00:43:19.319 --> 00:43:20.809 align:start position:0% are going to change the state of the contract<00:43:19.619> and<00:43:19.800> you<00:43:19.920> are<00:43:20.040> going<00:43:20.160> to<00:43:20.280> try<00:43:20.460> to<00:43:20.640> see 00:43:20.809 --> 00:43:20.819 align:start position:0% contract and you are going to try to see 00:43:20.819 --> 00:43:23.690 align:start position:0% contract and you are going to try to see the<00:43:21.000> environment<00:43:21.420> no<00:43:22.200> matter<00:43:22.380> the<00:43:22.680> state<00:43:22.859> and 00:43:23.690 --> 00:43:23.700 align:start position:0% the environment no matter the state and 00:43:23.700 --> 00:43:25.370 align:start position:0% the environment no matter the state and here<00:43:23.940> is<00:43:24.119> why<00:43:24.359> it's<00:43:24.540> important<00:43:24.839> that<00:43:25.020> echina 00:43:25.370 --> 00:43:25.380 align:start position:0% here is why it's important that echina 00:43:25.380 --> 00:43:26.630 align:start position:0% here is why it's important that echina is<00:43:25.560> calling<00:43:25.800> all<00:43:25.859> the<00:43:26.099> different<00:43:26.220> function 00:43:26.630 --> 00:43:26.640 align:start position:0% is calling all the different function 00:43:26.640 --> 00:43:28.490 align:start position:0% is calling all the different function because<00:43:27.180> it's<00:43:27.599> actually<00:43:27.839> what<00:43:28.079> you<00:43:28.200> want<00:43:28.380> to 00:43:28.490 --> 00:43:28.500 align:start position:0% because it's actually what you want to 00:43:28.500 --> 00:43:29.569 align:start position:0% because it's actually what you want to try 00:43:29.569 --> 00:43:29.579 align:start position:0% try 00:43:29.579 --> 00:43:32.930 align:start position:0% try the<00:43:29.880> balance<00:43:30.800> being<00:43:31.800> below<00:43:32.220> or<00:43:32.339> equal<00:43:32.520> to<00:43:32.760> the 00:43:32.930 --> 00:43:32.940 align:start position:0% the balance being below or equal to the 00:43:32.940 --> 00:43:35.270 align:start position:0% the balance being below or equal to the total<00:43:33.180> Supply<00:43:33.359> is<00:43:33.599> an<00:43:33.780> example<00:43:34.020> of<00:43:34.319> a<00:43:34.800> system 00:43:35.270 --> 00:43:35.280 align:start position:0% total Supply is an example of a system 00:43:35.280 --> 00:43:37.990 align:start position:0% total Supply is an example of a system level<00:43:35.579> invariant 00:43:37.990 --> 00:43:38.000 align:start position:0% level invariant 00:43:38.000 --> 00:43:41.569 align:start position:0% level invariant one<00:43:39.000> thing<00:43:39.119> that<00:43:39.300> you<00:43:39.480> can<00:43:39.599> use 00:43:41.569 --> 00:43:41.579 align:start position:0% one thing that you can use 00:43:41.579 --> 00:43:43.849 align:start position:0% one thing that you can use is<00:43:42.240> a<00:43:42.540> different<00:43:42.660> modern<00:43:43.079> incidence<00:43:43.500> of 00:43:43.849 --> 00:43:43.859 align:start position:0% is a different modern incidence of 00:43:43.859 --> 00:43:46.609 align:start position:0% is a different modern incidence of calling<00:43:44.220> Akinator<00:43:44.819> underscore<00:43:45.180> something<00:43:45.619> we 00:43:46.609 --> 00:43:46.619 align:start position:0% calling Akinator underscore something we 00:43:46.619 --> 00:43:48.349 align:start position:0% calling Akinator underscore something we support<00:43:46.800> a<00:43:47.040> session<00:43:47.280> so<00:43:47.520> you<00:43:47.640> can<00:43:47.760> just<00:43:47.940> create 00:43:48.349 --> 00:43:48.359 align:start position:0% support a session so you can just create 00:43:48.359 --> 00:43:50.870 align:start position:0% support a session so you can just create function<00:43:48.839> put<00:43:49.560> assertion<00:43:50.099> and<00:43:50.339> try<00:43:50.460> to<00:43:50.640> see<00:43:50.819> if 00:43:50.870 --> 00:43:50.880 align:start position:0% function put assertion and try to see if 00:43:50.880 --> 00:43:53.510 align:start position:0% function put assertion and try to see if it<00:43:51.000> holds 00:43:53.510 --> 00:43:53.520 align:start position:0% 00:43:53.520 --> 00:43:56.510 align:start position:0% a<00:43:54.000> SIM<00:43:54.300> for<00:43:54.780> system<00:43:55.380> level<00:43:55.619> environment<00:43:56.160> as<00:43:56.339> we 00:43:56.510 --> 00:43:56.520 align:start position:0% a SIM for system level environment as we 00:43:56.520 --> 00:43:58.370 align:start position:0% a SIM for system level environment as we kind<00:43:56.880> of<00:43:56.940> already<00:43:57.119> like<00:43:57.540> discuss<00:43:57.900> it<00:43:58.200> might<00:43:58.319> be 00:43:58.370 --> 00:43:58.380 align:start position:0% kind of already like discuss it might be 00:43:58.380 --> 00:43:59.690 align:start position:0% kind of already like discuss it might be more<00:43:58.619> complex<00:43:58.920> depending<00:43:59.400> on<00:43:59.579> the 00:43:59.690 --> 00:43:59.700 align:start position:0% more complex depending on the 00:43:59.700 --> 00:44:02.270 align:start position:0% more complex depending on the initialization<00:44:00.300> of<00:44:00.660> your<00:44:00.839> system<00:44:01.020> uh<00:44:01.980> if<00:44:02.160> it's 00:44:02.270 --> 00:44:02.280 align:start position:0% initialization of your system uh if it's 00:44:02.280 --> 00:44:03.770 align:start position:0% initialization of your system uh if it's a<00:44:02.460> simple<00:44:02.640> initialization<00:44:03.180> you<00:44:03.540> might<00:44:03.720> be 00:44:03.770 --> 00:44:03.780 align:start position:0% a simple initialization you might be 00:44:03.780 --> 00:44:05.270 align:start position:0% a simple initialization you might be able<00:44:03.960> to<00:44:04.079> do<00:44:04.260> everything<00:44:04.500> in<00:44:04.800> the<00:44:04.920> Constructor 00:44:05.270 --> 00:44:05.280 align:start position:0% able to do everything in the Constructor 00:44:05.280 --> 00:44:07.790 align:start position:0% able to do everything in the Constructor if<00:44:06.180> the<00:44:06.359> Constructor<00:44:06.720> is<00:44:06.960> too<00:44:07.140> large<00:44:07.380> for<00:44:07.619> like 00:44:07.790 --> 00:44:07.800 align:start position:0% if the Constructor is too large for like 00:44:07.800 --> 00:44:09.650 align:start position:0% if the Constructor is too large for like the<00:44:07.980> bytical<00:44:08.280> size<00:44:08.579> or<00:44:08.940> for<00:44:09.060> whatever<00:44:09.300> reason 00:44:09.650 --> 00:44:09.660 align:start position:0% the bytical size or for whatever reason 00:44:09.660 --> 00:44:12.170 align:start position:0% the bytical size or for whatever reason you<00:44:10.560> might<00:44:10.680> have<00:44:10.859> to<00:44:10.980> split<00:44:11.280> it<00:44:11.460> and<00:44:11.700> here<00:44:11.940> is 00:44:12.170 --> 00:44:12.180 align:start position:0% you might have to split it and here is 00:44:12.180 --> 00:44:15.589 align:start position:0% you might have to split it and here is where<00:44:12.420> you<00:44:12.540> can<00:44:12.660> use<00:44:12.780> a<00:44:12.900> kid<00:44:13.079> now<00:44:13.260> 18<00:44:14.099> outside 00:44:15.589 --> 00:44:15.599 align:start position:0% where you can use a kid now 18 outside 00:44:15.599 --> 00:44:19.329 align:start position:0% where you can use a kid now 18 outside okay 00:44:19.329 --> 00:44:19.339 align:start position:0% 00:44:19.339 --> 00:44:23.510 align:start position:0% all<00:44:20.339> right<00:44:20.579> so<00:44:21.000> let's<00:44:21.359> let's<00:44:21.900> see<00:44:22.440> this<00:44:23.220> uh 00:44:23.510 --> 00:44:23.520 align:start position:0% all right so let's let's see this uh 00:44:23.520 --> 00:44:25.790 align:start position:0% all right so let's let's see this uh particular<00:44:23.940> piece<00:44:24.240> of<00:44:24.300> code<00:44:24.480> let's<00:44:24.780> take 00:44:25.790 --> 00:44:25.800 align:start position:0% particular piece of code let's take 00:44:25.800 --> 00:44:26.450 align:start position:0% particular piece of code let's take um 00:44:26.450 --> 00:44:26.460 align:start position:0% um 00:44:26.460 --> 00:44:28.790 align:start position:0% um uh<00:44:26.819> half<00:44:27.240> a<00:44:27.420> minute<00:44:27.599> to<00:44:27.839> read<00:44:27.960> it 00:44:28.790 --> 00:44:28.800 align:start position:0% uh half a minute to read it 00:44:28.800 --> 00:44:31.490 align:start position:0% uh half a minute to read it um<00:44:28.920> it's<00:44:29.400> it's<00:44:29.880> basically<00:44:30.420> a<00:44:30.900> buy<00:44:31.079> function 00:44:31.490 --> 00:44:31.500 align:start position:0% um it's it's basically a buy function 00:44:31.500 --> 00:44:34.970 align:start position:0% um it's it's basically a buy function that<00:44:32.220> will<00:44:32.660> uh<00:44:33.660> call<00:44:33.900> an<00:44:34.260> internal<00:44:34.680> function 00:44:34.970 --> 00:44:34.980 align:start position:0% that will uh call an internal function 00:44:34.980 --> 00:44:38.150 align:start position:0% that will uh call an internal function valid<00:44:35.460> by<00:44:35.780> uh<00:44:36.780> so<00:44:37.079> what<00:44:37.380> we<00:44:37.500> are<00:44:37.619> going<00:44:37.800> to<00:44:37.980> do 00:44:38.150 --> 00:44:38.160 align:start position:0% valid by uh so what we are going to do 00:44:38.160 --> 00:44:41.750 align:start position:0% valid by uh so what we are going to do is<00:44:38.460> we're<00:44:38.940> going<00:44:39.180> to<00:44:39.359> think<00:44:39.920> uh<00:44:40.920> what<00:44:41.460> are<00:44:41.700> the 00:44:41.750 --> 00:44:41.760 align:start position:0% is we're going to think uh what are the 00:44:41.760 --> 00:44:44.390 align:start position:0% is we're going to think uh what are the type<00:44:42.000> of<00:44:42.240> invariants<00:44:43.020> that<00:44:43.380> we<00:44:43.619> can<00:44:43.740> have<00:44:44.040> here 00:44:44.390 --> 00:44:44.400 align:start position:0% type of invariants that we can have here 00:44:44.400 --> 00:44:47.210 align:start position:0% type of invariants that we can have here and<00:44:45.060> what<00:44:45.420> what<00:44:45.839> is<00:44:46.140> what<00:44:46.619> will<00:44:46.800> they<00:44:47.099> are 00:44:47.210 --> 00:44:47.220 align:start position:0% and what what is what will they are 00:44:47.220 --> 00:44:48.710 align:start position:0% and what what is what will they are going<00:44:47.339> to<00:44:47.460> test<00:44:47.700> and<00:44:48.000> what<00:44:48.359> type<00:44:48.599> of 00:44:48.710 --> 00:44:48.720 align:start position:0% going to test and what type of 00:44:48.720 --> 00:44:50.450 align:start position:0% going to test and what type of guarantees<00:44:49.319> we're<00:44:49.500> going<00:44:49.680> to<00:44:49.800> get<00:44:49.980> from<00:44:50.280> this 00:44:50.450 --> 00:44:50.460 align:start position:0% guarantees we're going to get from this 00:44:50.460 --> 00:44:52.730 align:start position:0% guarantees we're going to get from this so<00:44:50.940> let's<00:44:51.119> let's<00:44:51.480> take<00:44:51.780> a<00:44:51.960> few<00:44:52.140> few<00:44:52.560> seconds 00:44:52.730 --> 00:44:52.740 align:start position:0% so let's let's take a few few seconds 00:44:52.740 --> 00:44:55.309 align:start position:0% so let's let's take a few few seconds for<00:44:53.099> this 00:44:55.309 --> 00:44:55.319 align:start position:0% 00:44:55.319 --> 00:44:58.069 align:start position:0% foreign 00:44:58.069 --> 00:44:58.079 align:start position:0% 00:44:58.079 --> 00:45:05.089 align:start position:0% yes<00:44:58.920> so<00:44:59.160> we<00:44:59.339> have<00:44:59.460> questions 00:45:05.089 --> 00:45:05.099 align:start position:0% 00:45:05.099 --> 00:45:08.329 align:start position:0% okay<00:45:05.880> so<00:45:06.300> the<00:45:06.540> question<00:45:06.720> is<00:45:07.020> uh<00:45:07.680> testing 00:45:08.329 --> 00:45:08.339 align:start position:0% okay so the question is uh testing 00:45:08.339 --> 00:45:10.609 align:start position:0% okay so the question is uh testing timestamp<00:45:08.880> dependent<00:45:09.300> so<00:45:09.599> it's<00:45:09.960> clearly<00:45:10.380> not 00:45:10.609 --> 00:45:10.619 align:start position:0% timestamp dependent so it's clearly not 00:45:10.619 --> 00:45:12.950 align:start position:0% timestamp dependent so it's clearly not not<00:45:10.859> the<00:45:11.099> case<00:45:11.220> here<00:45:11.520> for<00:45:12.359> timestamp 00:45:12.950 --> 00:45:12.960 align:start position:0% not the case here for timestamp 00:45:12.960 --> 00:45:15.650 align:start position:0% not the case here for timestamp depending<00:45:13.440> code<00:45:13.740> uh 00:45:15.650 --> 00:45:15.660 align:start position:0% depending code uh 00:45:15.660 --> 00:45:17.510 align:start position:0% depending code uh um<00:45:15.780> a<00:45:16.079> kid<00:45:16.260> now<00:45:16.440> when<00:45:16.619> it<00:45:16.800> runs<00:45:17.280> it 00:45:17.510 --> 00:45:17.520 align:start position:0% um a kid now when it runs it 00:45:17.520 --> 00:45:21.109 align:start position:0% um a kid now when it runs it automatically<00:45:18.420> increase<00:45:19.040> either<00:45:20.040> the<00:45:20.760> block 00:45:21.109 --> 00:45:21.119 align:start position:0% automatically increase either the block 00:45:21.119 --> 00:45:23.990 align:start position:0% automatically increase either the block number<00:45:21.420> or<00:45:22.140> the<00:45:22.380> block<00:45:22.560> timestamp<00:45:23.099> inside 00:45:23.990 --> 00:45:24.000 align:start position:0% number or the block timestamp inside 00:45:24.000 --> 00:45:27.050 align:start position:0% number or the block timestamp inside some<00:45:24.420> range<00:45:25.020> right<00:45:25.859> because<00:45:26.339> it<00:45:26.640> it<00:45:26.819> happens 00:45:27.050 --> 00:45:27.060 align:start position:0% some range right because it it happens 00:45:27.060 --> 00:45:31.010 align:start position:0% some range right because it it happens that<00:45:27.660> some<00:45:27.900> code<00:45:28.200> will<00:45:28.560> fail<00:45:29.359> uh<00:45:30.359> when<00:45:30.839> the 00:45:31.010 --> 00:45:31.020 align:start position:0% that some code will fail uh when the 00:45:31.020 --> 00:45:33.770 align:start position:0% that some code will fail uh when the timestamp<00:45:31.500> is<00:45:31.859> increased<00:45:32.460> into<00:45:33.300> a<00:45:33.660> really 00:45:33.770 --> 00:45:33.780 align:start position:0% timestamp is increased into a really 00:45:33.780 --> 00:45:36.650 align:start position:0% timestamp is increased into a really really<00:45:33.960> large<00:45:34.319> number<00:45:34.680> but<00:45:35.640> yeah<00:45:35.940> 100<00:45:36.180> years 00:45:36.650 --> 00:45:36.660 align:start position:0% really large number but yeah 100 years 00:45:36.660 --> 00:45:38.809 align:start position:0% really large number but yeah 100 years or<00:45:37.020> like<00:45:37.319> the<00:45:37.500> end<00:45:37.859> of<00:45:37.980> the<00:45:38.099> universe<00:45:38.339> so<00:45:38.520> we 00:45:38.809 --> 00:45:38.819 align:start position:0% or like the end of the universe so we 00:45:38.819 --> 00:45:40.670 align:start position:0% or like the end of the universe so we don't<00:45:39.000> care<00:45:39.240> if<00:45:39.540> if<00:45:39.720> the<00:45:39.960> smart<00:45:40.140> contract<00:45:40.500> has 00:45:40.670 --> 00:45:40.680 align:start position:0% don't care if if the smart contract has 00:45:40.680 --> 00:45:43.670 align:start position:0% don't care if if the smart contract has a<00:45:40.920> bug<00:45:41.460> that<00:45:41.760> can<00:45:42.240> only<00:45:42.720> be<00:45:42.900> triggered<00:45:43.319> in<00:45:43.560> the 00:45:43.670 --> 00:45:43.680 align:start position:0% a bug that can only be triggered in the 00:45:43.680 --> 00:45:45.349 align:start position:0% a bug that can only be triggered in the end<00:45:43.740> of<00:45:43.920> the<00:45:43.980> universe<00:45:44.280> will<00:45:44.640> be<00:45:44.819> the<00:45:44.940> least<00:45:45.060> of 00:45:45.349 --> 00:45:45.359 align:start position:0% end of the universe will be the least of 00:45:45.359 --> 00:45:47.030 align:start position:0% end of the universe will be the least of our<00:45:45.660> problems 00:45:47.030 --> 00:45:47.040 align:start position:0% our problems 00:45:47.040 --> 00:45:50.809 align:start position:0% our problems um<00:45:47.160> all<00:45:47.760> right<00:45:47.880> so<00:45:48.680> yeah<00:45:49.680> any<00:45:49.980> any<00:45:50.220> idea<00:45:50.579> what 00:45:50.809 --> 00:45:50.819 align:start position:0% um all right so yeah any any idea what 00:45:50.819 --> 00:45:52.370 align:start position:0% um all right so yeah any any idea what are<00:45:51.000> the<00:45:51.060> type<00:45:51.240> of<00:45:51.359> things<00:45:51.720> that<00:45:51.960> we<00:45:52.079> can<00:45:52.200> test 00:45:52.370 --> 00:45:52.380 align:start position:0% are the type of things that we can test 00:45:52.380 --> 00:45:53.990 align:start position:0% are the type of things that we can test here 00:45:53.990 --> 00:45:54.000 align:start position:0% here 00:45:54.000 --> 00:45:56.530 align:start position:0% here first<00:45:54.780> one 00:45:56.530 --> 00:45:56.540 align:start position:0% first one 00:45:56.540 --> 00:46:00.230 align:start position:0% first one the<00:45:57.540> first<00:45:57.780> one<00:45:57.960> we<00:45:58.319> can<00:45:58.500> understand<00:45:58.740> that<00:45:59.579> how 00:46:00.230 --> 00:46:00.240 align:start position:0% the first one we can understand that how 00:46:00.240 --> 00:46:02.870 align:start position:0% the first one we can understand that how much<00:46:00.420> token<00:46:00.960> how<00:46:01.260> many<00:46:01.380> tokens<00:46:01.800> we<00:46:02.160> can<00:46:02.280> get<00:46:02.520> as 00:46:02.870 --> 00:46:02.880 align:start position:0% much token how many tokens we can get as 00:46:02.880 --> 00:46:06.170 align:start position:0% much token how many tokens we can get as a<00:46:03.119> result<00:46:03.619> follows<00:46:04.619> our<00:46:04.920> expectation<00:46:05.700> when 00:46:06.170 --> 00:46:06.180 align:start position:0% a result follows our expectation when 00:46:06.180 --> 00:46:09.230 align:start position:0% a result follows our expectation when we're<00:46:06.359> sending<00:46:06.839> message<00:46:07.680> value<00:46:08.099> because<00:46:08.940> as 00:46:09.230 --> 00:46:09.240 align:start position:0% we're sending message value because as 00:46:09.240 --> 00:46:11.870 align:start position:0% we're sending message value because as you<00:46:09.480> can<00:46:09.599> see<00:46:09.780> it's<00:46:10.140> a<00:46:10.500> hard-coded<00:46:11.220> rate<00:46:11.460> is 00:46:11.870 --> 00:46:11.880 align:start position:0% you can see it's a hard-coded rate is 00:46:11.880 --> 00:46:14.750 align:start position:0% you can see it's a hard-coded rate is around<00:46:12.180> 10<00:46:12.740> so<00:46:13.740> basically<00:46:14.160> it's<00:46:14.400> a<00:46:14.640> pretty 00:46:14.750 --> 00:46:14.760 align:start position:0% around 10 so basically it's a pretty 00:46:14.760 --> 00:46:17.569 align:start position:0% around 10 so basically it's a pretty simple<00:46:15.000> formula<00:46:15.720> we<00:46:16.140> can<00:46:16.319> change<00:46:16.800> different 00:46:17.569 --> 00:46:17.579 align:start position:0% simple formula we can change different 00:46:17.579 --> 00:46:20.030 align:start position:0% simple formula we can change different values<00:46:18.180> we<00:46:18.480> put<00:46:18.660> into<00:46:18.839> the<00:46:19.079> function<00:46:19.440> we<00:46:19.859> have 00:46:20.030 --> 00:46:20.040 align:start position:0% values we put into the function we have 00:46:20.040 --> 00:46:22.670 align:start position:0% values we put into the function we have totally<00:46:20.400> prediction<00:46:20.940> how<00:46:21.900> much<00:46:22.020> we<00:46:22.260> can<00:46:22.440> get 00:46:22.670 --> 00:46:22.680 align:start position:0% totally prediction how much we can get 00:46:22.680 --> 00:46:26.750 align:start position:0% totally prediction how much we can get and<00:46:23.339> then<00:46:23.579> we<00:46:23.880> can<00:46:24.060> try<00:46:24.420> to<00:46:25.220> verify<00:46:26.220> that<00:46:26.520> it 00:46:26.750 --> 00:46:26.760 align:start position:0% and then we can try to verify that it 00:46:26.760 --> 00:46:28.510 align:start position:0% and then we can try to verify that it works 00:46:28.510 --> 00:46:28.520 align:start position:0% works 00:46:28.520 --> 00:46:32.089 align:start position:0% works yes<00:46:29.520> exactly<00:46:30.000> so<00:46:30.420> the<00:46:30.720> the<00:46:31.020> property<00:46:31.980> is 00:46:32.089 --> 00:46:32.099 align:start position:0% yes exactly so the the property is 00:46:32.099 --> 00:46:34.490 align:start position:0% yes exactly so the the property is related<00:46:32.460> with<00:46:33.000> the<00:46:33.420> amount<00:46:33.660> that<00:46:33.960> we<00:46:34.140> can<00:46:34.319> get 00:46:34.490 --> 00:46:34.500 align:start position:0% related with the amount that we can get 00:46:34.500 --> 00:46:38.809 align:start position:0% related with the amount that we can get even<00:46:35.240> the<00:46:36.240> number<00:46:36.480> of<00:46:37.200> uh<00:46:37.980> weight<00:46:38.280> that<00:46:38.640> is 00:46:38.809 --> 00:46:38.819 align:start position:0% even the number of uh weight that is 00:46:38.819 --> 00:46:40.069 align:start position:0% even the number of uh weight that is sent 00:46:40.069 --> 00:46:40.079 align:start position:0% sent 00:46:40.079 --> 00:46:41.569 align:start position:0% sent so 00:46:41.569 --> 00:46:41.579 align:start position:0% so 00:46:41.579 --> 00:46:45.050 align:start position:0% so um<00:46:41.640> yeah<00:46:42.180> uh<00:46:42.839> we<00:46:43.140> can<00:46:43.339> so<00:46:44.339> the<00:46:44.579> first<00:46:44.700> thing<00:46:44.880> is 00:46:45.050 --> 00:46:45.060 align:start position:0% um yeah uh we can so the first thing is 00:46:45.060 --> 00:46:47.589 align:start position:0% um yeah uh we can so the first thing is this<00:46:45.540> this<00:46:45.780> code<00:46:46.079> will<00:46:46.380> depend<00:46:46.680> on<00:46:46.800> the<00:46:47.040> state 00:46:47.589 --> 00:46:47.599 align:start position:0% this this code will depend on the state 00:46:47.599 --> 00:46:50.150 align:start position:0% this this code will depend on the state uh<00:46:48.599> we<00:46:48.780> don't<00:46:48.900> have<00:46:49.079> the<00:46:49.260> mean<00:46:49.380> function<00:46:49.800> so<00:46:49.980> we 00:46:50.150 --> 00:46:50.160 align:start position:0% uh we don't have the mean function so we 00:46:50.160 --> 00:46:52.370 align:start position:0% uh we don't have the mean function so we don't<00:46:50.280> know<00:46:50.400> what<00:46:50.579> is<00:46:50.700> what<00:46:50.940> is<00:46:51.060> inside<00:46:51.380> where 00:46:52.370 --> 00:46:52.380 align:start position:0% don't know what is what is inside where 00:46:52.380 --> 00:46:54.770 align:start position:0% don't know what is what is inside where we<00:46:52.619> have<00:46:52.740> the<00:46:52.859> valid<00:46:53.160> buy<00:46:53.339> function<00:46:53.760> that<00:46:54.540> is 00:46:54.770 --> 00:46:54.780 align:start position:0% we have the valid buy function that is 00:46:54.780 --> 00:46:57.109 align:start position:0% we have the valid buy function that is actually<00:46:54.960> abstracting<00:46:55.740> the<00:46:56.099> thing<00:46:56.339> that<00:46:56.760> we 00:46:57.109 --> 00:46:57.119 align:start position:0% actually abstracting the thing that we 00:46:57.119 --> 00:47:01.190 align:start position:0% actually abstracting the thing that we want<00:46:57.300> to<00:46:57.599> that<00:46:58.440> we<00:46:58.619> want<00:46:58.859> to<00:46:58.980> test<00:46:59.300> so<00:47:00.300> we<00:47:00.960> will 00:47:01.190 --> 00:47:01.200 align:start position:0% want to that we want to test so we will 00:47:01.200 --> 00:47:04.190 align:start position:0% want to that we want to test so we will start<00:47:01.560> with<00:47:01.980> valid<00:47:02.640> by<00:47:02.760> which<00:47:03.060> is<00:47:03.300> a<00:47:03.720> pure 00:47:04.190 --> 00:47:04.200 align:start position:0% start with valid by which is a pure 00:47:04.200 --> 00:47:06.530 align:start position:0% start with valid by which is a pure stateless<00:47:04.740> function 00:47:06.530 --> 00:47:06.540 align:start position:0% stateless function 00:47:06.540 --> 00:47:07.190 align:start position:0% stateless function um 00:47:07.190 --> 00:47:07.200 align:start position:0% um 00:47:07.200 --> 00:47:11.690 align:start position:0% um yes<00:47:08.160> so<00:47:08.880> we<00:47:09.540> were<00:47:09.720> thinking<00:47:10.319> about<00:47:10.700> invariance 00:47:11.690 --> 00:47:11.700 align:start position:0% yes so we were thinking about invariance 00:47:11.700 --> 00:47:14.150 align:start position:0% yes so we were thinking about invariance here<00:47:11.940> related<00:47:12.480> with 00:47:14.150 --> 00:47:14.160 align:start position:0% here related with 00:47:14.160 --> 00:47:16.849 align:start position:0% here related with um<00:47:14.220> the<00:47:14.700> amount<00:47:15.000> that<00:47:15.300> we<00:47:15.480> can<00:47:15.599> get<00:47:15.780> so<00:47:16.500> this<00:47:16.740> is 00:47:16.849 --> 00:47:16.859 align:start position:0% um the amount that we can get so this is 00:47:16.859 --> 00:47:18.890 align:start position:0% um the amount that we can get so this is these<00:47:17.220> are<00:47:17.339> very<00:47:17.520> simple<00:47:17.700> without<00:47:18.300> going<00:47:18.660> into 00:47:18.890 --> 00:47:18.900 align:start position:0% these are very simple without going into 00:47:18.900 --> 00:47:21.770 align:start position:0% these are very simple without going into specific<00:47:19.819> uh<00:47:20.819> this<00:47:21.119> is<00:47:21.300> a<00:47:21.480> very<00:47:21.599> simple 00:47:21.770 --> 00:47:21.780 align:start position:0% specific uh this is a very simple 00:47:21.780 --> 00:47:24.170 align:start position:0% specific uh this is a very simple invariant<00:47:22.440> if<00:47:22.920> the<00:47:23.099> amount<00:47:23.400> if<00:47:23.640> the<00:47:23.819> Wayside 00:47:24.170 --> 00:47:24.180 align:start position:0% invariant if the amount if the Wayside 00:47:24.180 --> 00:47:28.309 align:start position:0% invariant if the amount if the Wayside in<00:47:24.359> C<00:47:24.540> is<00:47:24.839> zero<00:47:25.260> then<00:47:26.180> the<00:47:27.180> user<00:47:27.540> should 00:47:28.309 --> 00:47:28.319 align:start position:0% in C is zero then the user should 00:47:28.319 --> 00:47:31.490 align:start position:0% in C is zero then the user should receive<00:47:28.980> no<00:47:29.280> tokens<00:47:29.700> at<00:47:29.819> all<00:47:30.359> right<00:47:30.960> so<00:47:31.140> so 00:47:31.490 --> 00:47:31.500 align:start position:0% receive no tokens at all right so so 00:47:31.500 --> 00:47:33.290 align:start position:0% receive no tokens at all right so so that's<00:47:31.800> it's<00:47:32.099> it's<00:47:32.220> even<00:47:32.640> simple<00:47:32.940> and 00:47:33.290 --> 00:47:33.300 align:start position:0% that's it's it's even simple and 00:47:33.300 --> 00:47:36.170 align:start position:0% that's it's it's even simple and thinking<00:47:33.780> how<00:47:34.079> how<00:47:34.380> much<00:47:34.560> well<00:47:35.280> I<00:47:35.579> a<00:47:35.880> user 00:47:36.170 --> 00:47:36.180 align:start position:0% thinking how how much well I a user 00:47:36.180 --> 00:47:38.650 align:start position:0% thinking how how much well I a user should<00:47:36.420> receive<00:47:36.720> but<00:47:37.380> it's<00:47:37.680> a<00:47:37.859> Concrete<00:47:38.280> case 00:47:38.650 --> 00:47:38.660 align:start position:0% should receive but it's a Concrete case 00:47:38.660 --> 00:47:41.930 align:start position:0% should receive but it's a Concrete case and<00:47:39.660> it's<00:47:39.960> it's<00:47:40.260> kind<00:47:40.859> of<00:47:40.920> a<00:47:41.099> corner<00:47:41.460> case<00:47:41.579> so 00:47:41.930 --> 00:47:41.940 align:start position:0% and it's it's kind of a corner case so 00:47:41.940 --> 00:47:45.589 align:start position:0% and it's it's kind of a corner case so it's<00:47:42.480> it<00:47:42.720> can<00:47:42.960> be<00:47:43.140> important<00:47:43.680> to<00:47:43.800> test 00:47:45.589 --> 00:47:45.599 align:start position:0% it's it can be important to test 00:47:45.599 --> 00:47:49.430 align:start position:0% it's it can be important to test all<00:47:46.319> right<00:47:46.500> so<00:47:47.160> how<00:47:47.700> we<00:47:47.940> can<00:47:48.119> test<00:47:48.359> this<00:47:48.780> so 00:47:49.430 --> 00:47:49.440 align:start position:0% all right so how we can test this so 00:47:49.440 --> 00:47:51.109 align:start position:0% all right so how we can test this so there<00:47:49.680> are<00:47:49.980> a<00:47:50.040> couple<00:47:50.160> of<00:47:50.280> way<00:47:50.520> to<00:47:50.700> test<00:47:50.880> it 00:47:51.109 --> 00:47:51.119 align:start position:0% there are a couple of way to test it 00:47:51.119 --> 00:47:52.130 align:start position:0% there are a couple of way to test it this<00:47:51.420> is 00:47:52.130 --> 00:47:52.140 align:start position:0% this is 00:47:52.140 --> 00:47:56.329 align:start position:0% this is um this<00:47:52.619> is<00:47:52.680> one<00:47:53.119> so<00:47:54.119> we<00:47:54.960> we<00:47:55.319> can<00:47:55.560> write<00:47:55.920> a 00:47:56.329 --> 00:47:56.339 align:start position:0% um this is one so we we can write a 00:47:56.339 --> 00:47:59.450 align:start position:0% um this is one so we we can write a function<00:47:56.700> that<00:47:57.119> will<00:47:57.300> take<00:47:57.660> uh<00:47:58.560> one<00:47:58.859> parameter 00:47:59.450 --> 00:47:59.460 align:start position:0% function that will take uh one parameter 00:47:59.460 --> 00:48:02.450 align:start position:0% function that will take uh one parameter so<00:47:59.700> again<00:47:59.880> I<00:48:00.180> will<00:48:00.300> put<00:48:00.540> any<00:48:00.900> any<00:48:01.619> number<00:48:02.099> there 00:48:02.450 --> 00:48:02.460 align:start position:0% so again I will put any any number there 00:48:02.460 --> 00:48:06.109 align:start position:0% so again I will put any any number there however<00:48:03.300> we're<00:48:03.960> going<00:48:04.200> to<00:48:04.380> restrict<00:48:05.119> the 00:48:06.109 --> 00:48:06.119 align:start position:0% however we're going to restrict the 00:48:06.119 --> 00:48:08.690 align:start position:0% however we're going to restrict the number<00:48:06.359> uh<00:48:07.200> the<00:48:07.380> input<00:48:07.619> of<00:48:07.980> this<00:48:08.099> function<00:48:08.400> to 00:48:08.690 --> 00:48:08.700 align:start position:0% number uh the input of this function to 00:48:08.700 --> 00:48:10.790 align:start position:0% number uh the input of this function to be<00:48:08.880> non-zero 00:48:10.790 --> 00:48:10.800 align:start position:0% be non-zero 00:48:10.800 --> 00:48:14.750 align:start position:0% be non-zero uh<00:48:11.700> then<00:48:11.880> we're<00:48:12.060> going<00:48:12.240> to<00:48:12.359> execute<00:48:12.780> valid<00:48:13.200> by 00:48:14.750 --> 00:48:14.760 align:start position:0% uh then we're going to execute valid by 00:48:14.760 --> 00:48:15.650 align:start position:0% uh then we're going to execute valid by um<00:48:14.880> and 00:48:15.650 --> 00:48:15.660 align:start position:0% um and 00:48:15.660 --> 00:48:19.730 align:start position:0% um and then<00:48:16.640> we<00:48:17.640> want<00:48:17.760> to<00:48:17.940> know<00:48:18.180> if<00:48:18.660> echina<00:48:19.140> can<00:48:19.440> reach 00:48:19.730 --> 00:48:19.740 align:start position:0% then we want to know if echina can reach 00:48:19.740 --> 00:48:21.890 align:start position:0% then we want to know if echina can reach he<00:48:20.339> can<00:48:20.579> reach<00:48:20.940> the 00:48:21.890 --> 00:48:21.900 align:start position:0% he can reach the 00:48:21.900 --> 00:48:24.829 align:start position:0% he can reach the um<00:48:21.960> the<00:48:22.500> statement<00:48:23.339> after<00:48:23.940> that<00:48:24.240> because 00:48:24.829 --> 00:48:24.839 align:start position:0% um the statement after that because 00:48:24.839 --> 00:48:30.050 align:start position:0% um the statement after that because valid<00:48:25.380> by<00:48:25.560> Will<00:48:26.099> revert<00:48:26.819> if<00:48:27.780> if<00:48:28.319> the<00:48:29.040> uh<00:48:29.700> if<00:48:29.940> the 00:48:30.050 --> 00:48:30.060 align:start position:0% valid by Will revert if if the uh if the 00:48:30.060 --> 00:48:34.370 align:start position:0% valid by Will revert if if the uh if the inputs<00:48:30.480> are<00:48:30.900> not<00:48:31.339> uh<00:48:32.339> the<00:48:32.520> one<00:48:32.640> expected 00:48:34.370 --> 00:48:34.380 align:start position:0% inputs are not uh the one expected 00:48:34.380 --> 00:48:37.670 align:start position:0% inputs are not uh the one expected um<00:48:34.440> so<00:48:34.920> we<00:48:35.220> want<00:48:35.460> to<00:48:35.640> know<00:48:35.880> if<00:48:36.359> we<00:48:36.599> can<00:48:36.720> get<00:48:37.020> if 00:48:37.670 --> 00:48:37.680 align:start position:0% um so we want to know if we can get if 00:48:37.680 --> 00:48:41.690 align:start position:0% um so we want to know if we can get if we<00:48:37.859> can<00:48:37.980> get<00:48:38.099> tokens<00:48:38.579> despite<00:48:39.060> sending<00:48:40.380> no 00:48:41.690 --> 00:48:41.700 align:start position:0% we can get tokens despite sending no 00:48:41.700 --> 00:48:45.530 align:start position:0% we can get tokens despite sending no um<00:48:41.760> no<00:48:42.240> value<00:48:42.480> right 00:48:45.530 --> 00:48:45.540 align:start position:0% 00:48:45.540 --> 00:48:47.530 align:start position:0% and 00:48:47.530 --> 00:48:47.540 align:start position:0% and 00:48:47.540 --> 00:48:50.930 align:start position:0% and so<00:48:48.540> perhaps<00:48:48.960> you're<00:48:49.200> wondering<00:48:49.619> what<00:48:50.160> if<00:48:50.339> what 00:48:50.930 --> 00:48:50.940 align:start position:0% so perhaps you're wondering what if what 00:48:50.940 --> 00:48:55.130 align:start position:0% so perhaps you're wondering what if what if<00:48:51.180> the<00:48:51.599> ceremony<00:48:52.079> is<00:48:52.319> zero<00:48:53.099> uh<00:48:54.060> then<00:48:54.480> clearly 00:48:55.130 --> 00:48:55.140 align:start position:0% if the ceremony is zero uh then clearly 00:48:55.140 --> 00:48:56.870 align:start position:0% if the ceremony is zero uh then clearly this<00:48:55.440> code<00:48:55.619> will<00:48:55.920> not<00:48:56.160> do<00:48:56.640> anything 00:48:56.870 --> 00:48:56.880 align:start position:0% this code will not do anything 00:48:56.880 --> 00:48:59.270 align:start position:0% this code will not do anything interesting<00:48:57.420> so<00:48:57.960> she<00:48:58.260> was<00:48:58.380> just<00:48:58.560> is<00:48:58.859> going<00:48:59.099> to 00:48:59.270 --> 00:48:59.280 align:start position:0% interesting so she was just is going to 00:48:59.280 --> 00:49:00.290 align:start position:0% interesting so she was just is going to revert 00:49:00.290 --> 00:49:00.300 align:start position:0% revert 00:49:00.300 --> 00:49:04.370 align:start position:0% revert uh<00:49:00.839> when<00:49:01.020> you're<00:49:01.200> writing<00:49:01.819> tests<00:49:03.079> you<00:49:04.079> need<00:49:04.260> to 00:49:04.370 --> 00:49:04.380 align:start position:0% uh when you're writing tests you need to 00:49:04.380 --> 00:49:06.309 align:start position:0% uh when you're writing tests you need to so<00:49:04.740> you<00:49:04.920> can<00:49:04.980> put<00:49:05.160> any<00:49:05.339> any<00:49:05.700> amount<00:49:06.119> of 00:49:06.309 --> 00:49:06.319 align:start position:0% so you can put any any amount of 00:49:06.319 --> 00:49:09.530 align:start position:0% so you can put any any amount of requires<00:49:07.319> or<00:49:07.680> preconditions<00:49:08.579> or<00:49:09.000> people 00:49:09.530 --> 00:49:09.540 align:start position:0% requires or preconditions or people 00:49:09.540 --> 00:49:13.609 align:start position:0% requires or preconditions or people usually<00:49:10.020> call<00:49:10.260> it<00:49:10.380> however<00:49:11.339> if<00:49:11.700> you<00:49:11.819> put<00:49:12.140> uh<00:49:13.140> if 00:49:13.609 --> 00:49:13.619 align:start position:0% usually call it however if you put uh if 00:49:13.619 --> 00:49:16.089 align:start position:0% usually call it however if you put uh if the<00:49:13.740> preconditions<00:49:14.460> are<00:49:14.700> too<00:49:14.940> restrictive 00:49:16.089 --> 00:49:16.099 align:start position:0% the preconditions are too restrictive 00:49:16.099 --> 00:49:19.970 align:start position:0% the preconditions are too restrictive and<00:49:17.099> your<00:49:17.819> uh<00:49:18.359> your<00:49:18.720> function<00:49:19.020> reverts<00:49:19.680> most 00:49:19.970 --> 00:49:19.980 align:start position:0% and your uh your function reverts most 00:49:19.980 --> 00:49:22.550 align:start position:0% and your uh your function reverts most of<00:49:20.099> the<00:49:20.280> time<00:49:20.460> it<00:49:21.300> means<00:49:21.599> like<00:49:21.900> you're<00:49:22.319> not 00:49:22.550 --> 00:49:22.560 align:start position:0% of the time it means like you're not 00:49:22.560 --> 00:49:25.250 align:start position:0% of the time it means like you're not going<00:49:22.800> to<00:49:23.040> get<00:49:23.280> value<00:49:23.640> from<00:49:24.000> the<00:49:24.180> execution<00:49:24.540> so 00:49:25.250 --> 00:49:25.260 align:start position:0% going to get value from the execution so 00:49:25.260 --> 00:49:27.890 align:start position:0% going to get value from the execution so every<00:49:25.500> execution<00:49:26.040> reverted<00:49:26.819> in<00:49:27.180> a<00:49:27.300> test<00:49:27.480> in<00:49:27.780> an 00:49:27.890 --> 00:49:27.900 align:start position:0% every execution reverted in a test in an 00:49:27.900 --> 00:49:30.589 align:start position:0% every execution reverted in a test in an invariant<00:49:28.380> let's<00:49:28.619> say<00:49:28.800> that<00:49:29.339> every<00:49:29.819> every 00:49:30.589 --> 00:49:30.599 align:start position:0% invariant let's say that every every 00:49:30.599 --> 00:49:34.069 align:start position:0% invariant let's say that every every case<00:49:31.020> that<00:49:31.560> you<00:49:31.859> don't<00:49:32.040> uh<00:49:32.940> that<00:49:33.660> you<00:49:33.900> don't 00:49:34.069 --> 00:49:34.079 align:start position:0% case that you don't uh that you don't 00:49:34.079 --> 00:49:37.790 align:start position:0% case that you don't uh that you don't use<00:49:34.619> it's<00:49:35.280> going<00:49:35.460> to<00:49:35.640> be<00:49:35.940> an<00:49:36.900> execution<00:49:37.380> an 00:49:37.790 --> 00:49:37.800 align:start position:0% use it's going to be an execution an 00:49:37.800 --> 00:49:40.609 align:start position:0% use it's going to be an execution an execution<00:49:38.460> that<00:49:39.000> you<00:49:39.180> waste<00:49:39.660> so<00:49:40.260> in<00:49:40.380> this<00:49:40.500> case 00:49:40.609 --> 00:49:40.619 align:start position:0% execution that you waste so in this case 00:49:40.619 --> 00:49:43.670 align:start position:0% execution that you waste so in this case you<00:49:40.859> only<00:49:41.040> waste<00:49:41.460> one<00:49:41.760> one<00:49:42.060> execution<00:49:42.660> in<00:49:43.560> a 00:49:43.670 --> 00:49:43.680 align:start position:0% you only waste one one execution in a 00:49:43.680 --> 00:49:46.990 align:start position:0% you only waste one one execution in a range<00:49:43.980> of<00:49:44.339> in<00:49:44.940> the<00:49:45.060> full<00:49:45.180> range<00:49:45.540> of<00:49:45.720> uh<00:49:46.140> uins 00:49:46.990 --> 00:49:47.000 align:start position:0% range of in the full range of uh uins 00:49:47.000 --> 00:49:49.970 align:start position:0% range of in the full range of uh uins 256.<00:49:48.000> so<00:49:48.359> it's<00:49:48.480> not<00:49:48.660> a<00:49:48.839> big<00:49:48.900> deal<00:49:49.079> but<00:49:49.619> if<00:49:49.800> you 00:49:49.970 --> 00:49:49.980 align:start position:0% 256. so it's not a big deal but if you 00:49:49.980 --> 00:49:52.670 align:start position:0% 256. so it's not a big deal but if you have<00:49:50.220> if<00:49:50.880> you<00:49:51.119> put<00:49:51.359> a<00:49:51.540> lot<00:49:51.599> of<00:49:51.720> requires<00:49:52.380> that 00:49:52.670 --> 00:49:52.680 align:start position:0% have if you put a lot of requires that 00:49:52.680 --> 00:49:55.730 align:start position:0% have if you put a lot of requires that only<00:49:53.040> a<00:49:53.640> very<00:49:53.819> small<00:49:54.180> small<00:49:54.660> amount<00:49:55.020> of<00:49:55.200> uh 00:49:55.730 --> 00:49:55.740 align:start position:0% only a very small small amount of uh 00:49:55.740 --> 00:49:58.130 align:start position:0% only a very small small amount of uh values<00:49:56.520> well<00:49:56.819> satisfied<00:49:57.300> and<00:49:57.660> it<00:49:57.839> will<00:49:57.960> be 00:49:58.130 --> 00:49:58.140 align:start position:0% values well satisfied and it will be 00:49:58.140 --> 00:50:01.010 align:start position:0% values well satisfied and it will be difficult<00:49:58.380> to<00:49:58.680> get<00:49:58.859> randomly<00:49:59.760> or<00:50:00.119> even<00:50:00.420> even 00:50:01.010 --> 00:50:01.020 align:start position:0% difficult to get randomly or even even 00:50:01.020 --> 00:50:03.170 align:start position:0% difficult to get randomly or even even with<00:50:01.560> the<00:50:01.800> with<00:50:02.220> the<00:50:02.400> techniques<00:50:02.760> that<00:50:02.880> we<00:50:03.000> use 00:50:03.170 --> 00:50:03.180 align:start position:0% with the with the techniques that we use 00:50:03.180 --> 00:50:04.970 align:start position:0% with the with the techniques that we use you<00:50:03.900> will<00:50:04.020> need<00:50:04.260> a<00:50:04.500> slightly<00:50:04.800> different 00:50:04.970 --> 00:50:04.980 align:start position:0% you will need a slightly different 00:50:04.980 --> 00:50:07.609 align:start position:0% you will need a slightly different approach<00:50:05.819> but<00:50:06.000> yeah<00:50:06.240> we<00:50:06.480> will<00:50:06.660> we<00:50:06.960> will<00:50:07.140> uh 00:50:07.609 --> 00:50:07.619 align:start position:0% approach but yeah we will we will uh 00:50:07.619 --> 00:50:10.190 align:start position:0% approach but yeah we will we will uh then<00:50:08.160> go<00:50:08.280> later<00:50:08.520> into<00:50:08.760> that<00:50:08.940> so<00:50:09.720> any<00:50:09.960> any 00:50:10.190 --> 00:50:10.200 align:start position:0% then go later into that so any any 00:50:10.200 --> 00:50:11.390 align:start position:0% then go later into that so any any questions 00:50:11.390 --> 00:50:11.400 align:start position:0% questions 00:50:11.400 --> 00:50:16.809 align:start position:0% questions yes 00:50:16.809 --> 00:50:16.819 align:start position:0% 00:50:16.819 --> 00:50:19.970 align:start position:0% yeah<00:50:17.819> so<00:50:18.119> as<00:50:18.420> you<00:50:18.599> mentioned<00:50:18.960> uh<00:50:19.500> in<00:50:19.740> this<00:50:19.859> case 00:50:19.970 --> 00:50:19.980 align:start position:0% yeah so as you mentioned uh in this case 00:50:19.980 --> 00:50:22.730 align:start position:0% yeah so as you mentioned uh in this case that<00:50:20.400> we<00:50:20.880> are<00:50:21.180> basically<00:50:21.839> sacrificing<00:50:22.500> only 00:50:22.730 --> 00:50:22.740 align:start position:0% that we are basically sacrificing only 00:50:22.740 --> 00:50:24.950 align:start position:0% that we are basically sacrificing only one<00:50:23.040> uh<00:50:23.339> one<00:50:23.579> case<00:50:23.700> which<00:50:23.940> is<00:50:24.119> when<00:50:24.359> it's<00:50:24.540> zero 00:50:24.950 --> 00:50:24.960 align:start position:0% one uh one case which is when it's zero 00:50:24.960 --> 00:50:27.650 align:start position:0% one uh one case which is when it's zero uh<00:50:25.740> but<00:50:25.980> is<00:50:26.280> it<00:50:26.400> gonna<00:50:26.520> run<00:50:26.819> over<00:50:27.180> the<00:50:27.480> whole 00:50:27.650 --> 00:50:27.660 align:start position:0% uh but is it gonna run over the whole 00:50:27.660 --> 00:50:30.349 align:start position:0% uh but is it gonna run over the whole range<00:50:27.960> of<00:50:28.160> un256<00:50:29.160> because<00:50:29.460> that's<00:50:29.880> a<00:50:30.240> really 00:50:30.349 --> 00:50:30.359 align:start position:0% range of un256 because that's a really 00:50:30.359 --> 00:50:32.030 align:start position:0% range of un256 because that's a really large<00:50:30.599> range<00:50:30.900> and<00:50:31.079> and<00:50:31.500> it<00:50:31.680> doesn't<00:50:31.859> make 00:50:32.030 --> 00:50:32.040 align:start position:0% large range and and it doesn't make 00:50:32.040 --> 00:50:34.069 align:start position:0% large range and and it doesn't make sense<00:50:32.220> to<00:50:32.520> test<00:50:32.700> all<00:50:33.000> of<00:50:33.180> that<00:50:33.300> in<00:50:33.720> some<00:50:33.839> cases 00:50:34.069 --> 00:50:34.079 align:start position:0% sense to test all of that in some cases 00:50:34.079 --> 00:50:36.710 align:start position:0% sense to test all of that in some cases yeah<00:50:34.380> exactly<00:50:34.680> so<00:50:34.920> it<00:50:35.040> won't 00:50:36.710 --> 00:50:36.720 align:start position:0% yeah exactly so it won't 00:50:36.720 --> 00:50:38.809 align:start position:0% yeah exactly so it won't there<00:50:37.200> will<00:50:37.380> there<00:50:37.740> is<00:50:37.920> no<00:50:38.099> tool<00:50:38.460> in<00:50:38.579> the<00:50:38.700> world 00:50:38.809 --> 00:50:38.819 align:start position:0% there will there is no tool in the world 00:50:38.819 --> 00:50:41.589 align:start position:0% there will there is no tool in the world that<00:50:39.060> can<00:50:39.240> run<00:50:39.480> for<00:50:39.900> all<00:50:40.260> the<00:50:40.440> all<00:50:40.980> the<00:50:41.160> range 00:50:41.589 --> 00:50:41.599 align:start position:0% that can run for all the all the range 00:50:41.599 --> 00:50:45.890 align:start position:0% that can run for all the all the range uh<00:50:42.599> it<00:50:42.839> is<00:50:43.140> always<00:50:43.579> either<00:50:44.579> either<00:50:45.119> uh 00:50:45.890 --> 00:50:45.900 align:start position:0% uh it is always either either uh 00:50:45.900 --> 00:50:47.510 align:start position:0% uh it is always either either uh symbolic<00:50:46.560> I<00:50:46.740> mean<00:50:46.859> you<00:50:47.040> can<00:50:47.160> do<00:50:47.280> it 00:50:47.510 --> 00:50:47.520 align:start position:0% symbolic I mean you can do it 00:50:47.520 --> 00:50:49.970 align:start position:0% symbolic I mean you can do it symbolically<00:50:48.300> but<00:50:48.900> it's<00:50:49.020> it's<00:50:49.260> not<00:50:49.619> it's<00:50:49.740> not 00:50:49.970 --> 00:50:49.980 align:start position:0% symbolically but it's it's not it's not 00:50:49.980 --> 00:50:51.349 align:start position:0% symbolically but it's it's not it's not going<00:50:50.099> to<00:50:50.220> test<00:50:50.400> all<00:50:50.760> the<00:50:50.880> values<00:50:51.180> it's 00:50:51.349 --> 00:50:51.359 align:start position:0% going to test all the values it's 00:50:51.359 --> 00:50:53.270 align:start position:0% going to test all the values it's another<00:50:51.900> thing 00:50:53.270 --> 00:50:53.280 align:start position:0% another thing 00:50:53.280 --> 00:50:56.030 align:start position:0% another thing um<00:50:53.339> and<00:50:54.300> uh<00:50:54.960> fasting<00:50:55.380> techniques<00:50:55.740> are<00:50:55.859> going 00:50:56.030 --> 00:50:56.040 align:start position:0% um and uh fasting techniques are going 00:50:56.040 --> 00:50:59.750 align:start position:0% um and uh fasting techniques are going to<00:50:56.280> sample<00:50:56.880> let's<00:50:57.780> say<00:50:57.960> randomly<00:50:58.619> from<00:50:59.339> the 00:50:59.750 --> 00:50:59.760 align:start position:0% to sample let's say randomly from the 00:50:59.760 --> 00:51:04.490 align:start position:0% to sample let's say randomly from the from<00:51:00.420> the<00:51:00.599> input<00:51:00.900> or<00:51:01.559> with<00:51:01.920> hubs<00:51:02.700> right 00:51:04.490 --> 00:51:04.500 align:start position:0% from the input or with hubs right 00:51:04.500 --> 00:51:07.549 align:start position:0% from the input or with hubs right um<00:51:04.559> it's<00:51:05.339> in<00:51:05.760> the<00:51:05.940> case<00:51:06.059> of<00:51:06.180> Echidna<00:51:06.780> since<00:51:07.319> we 00:51:07.549 --> 00:51:07.559 align:start position:0% um it's in the case of Echidna since we 00:51:07.559 --> 00:51:09.349 align:start position:0% um it's in the case of Echidna since we are<00:51:07.680> going<00:51:07.800> to<00:51:07.859> compile<00:51:08.220> this<00:51:08.520> code<00:51:08.760> and<00:51:09.300> it 00:51:09.349 --> 00:51:09.359 align:start position:0% are going to compile this code and it 00:51:09.359 --> 00:51:11.690 align:start position:0% are going to compile this code and it will<00:51:09.540> run<00:51:09.660> through<00:51:09.900> or<00:51:10.200> static<00:51:10.559> analyzer<00:51:11.099> we 00:51:11.690 --> 00:51:11.700 align:start position:0% will run through or static analyzer we 00:51:11.700 --> 00:51:14.210 align:start position:0% will run through or static analyzer we will<00:51:11.880> detect<00:51:12.240> some<00:51:12.540> interesting<00:51:12.960> values 00:51:14.210 --> 00:51:14.220 align:start position:0% will detect some interesting values 00:51:14.220 --> 00:51:16.250 align:start position:0% will detect some interesting values in<00:51:15.000> this<00:51:15.119> case 00:51:16.250 --> 00:51:16.260 align:start position:0% in this case 00:51:16.260 --> 00:51:18.890 align:start position:0% in this case um<00:51:16.400> 10<00:51:17.400> for<00:51:17.760> instance<00:51:17.940> 10<00:51:18.300> 10<00:51:18.599> is<00:51:18.780> an 00:51:18.890 --> 00:51:18.900 align:start position:0% um 10 for instance 10 10 is an 00:51:18.900 --> 00:51:21.349 align:start position:0% um 10 for instance 10 10 is an interesting<00:51:19.260> value<00:51:19.440> there<00:51:20.339> it's<00:51:20.819> a<00:51:21.000> it's<00:51:21.180> a 00:51:21.349 --> 00:51:21.359 align:start position:0% interesting value there it's a it's a 00:51:21.359 --> 00:51:22.670 align:start position:0% interesting value there it's a it's a constant<00:51:21.660> and<00:51:21.839> it's<00:51:22.020> going<00:51:22.200> to<00:51:22.319> be<00:51:22.440> used 00:51:22.670 --> 00:51:22.680 align:start position:0% constant and it's going to be used 00:51:22.680 --> 00:51:25.490 align:start position:0% constant and it's going to be used somewhere<00:51:23.160> so<00:51:23.880> definitely<00:51:24.300> we<00:51:24.720> want<00:51:24.900> to<00:51:25.079> we 00:51:25.490 --> 00:51:25.500 align:start position:0% somewhere so definitely we want to we 00:51:25.500 --> 00:51:27.890 align:start position:0% somewhere so definitely we want to we want<00:51:25.680> to<00:51:25.800> test<00:51:25.980> with<00:51:26.220> that<00:51:26.460> constant<00:51:26.880> okay<00:51:27.599> so 00:51:27.890 --> 00:51:27.900 align:start position:0% want to test with that constant okay so 00:51:27.900 --> 00:51:30.890 align:start position:0% want to test with that constant okay so let's<00:51:28.079> see<00:51:28.319> what<00:51:28.559> happens<00:51:28.800> if<00:51:29.460> we<00:51:29.700> if<00:51:30.480> you<00:51:30.660> if 00:51:30.890 --> 00:51:30.900 align:start position:0% let's see what happens if we if you if 00:51:30.900 --> 00:51:34.849 align:start position:0% let's see what happens if we if you if you<00:51:31.079> run<00:51:31.260> so<00:51:31.559> this<00:51:32.460> is<00:51:32.640> uh<00:51:33.480> uh<00:51:34.020> so<00:51:34.200> kinda<00:51:34.680> will 00:51:34.849 --> 00:51:34.859 align:start position:0% you run so this is uh uh so kinda will 00:51:34.859 --> 00:51:36.710 align:start position:0% you run so this is uh uh so kinda will run<00:51:35.040> a<00:51:35.280> number<00:51:35.400> of<00:51:35.520> transactions<00:51:36.180> it<00:51:36.540> will 00:51:36.710 --> 00:51:36.720 align:start position:0% run a number of transactions it will 00:51:36.720 --> 00:51:39.470 align:start position:0% run a number of transactions it will eventually<00:51:37.200> detect<00:51:38.099> that<00:51:38.640> assernal<00:51:39.300> free 00:51:39.470 --> 00:51:39.480 align:start position:0% eventually detect that assernal free 00:51:39.480 --> 00:51:42.170 align:start position:0% eventually detect that assernal free token<00:51:39.900> has<00:51:40.260> an<00:51:40.440> assertion<00:51:40.859> failure<00:51:41.220> however 00:51:42.170 --> 00:51:42.180 align:start position:0% token has an assertion failure however 00:51:42.180 --> 00:51:44.690 align:start position:0% token has an assertion failure however this<00:51:42.720> is<00:51:42.960> going<00:51:43.079> to<00:51:43.200> be<00:51:43.260> in<00:51:43.440> a<00:51:43.559> context<00:51:43.859> of<00:51:44.160> 100 00:51:44.690 --> 00:51:44.700 align:start position:0% this is going to be in a context of 100 00:51:44.700 --> 00:51:47.210 align:start position:0% this is going to be in a context of 100 of<00:51:45.059> transactions<00:51:45.660> random<00:51:46.380> transactions<00:51:46.980> that 00:51:47.210 --> 00:51:47.220 align:start position:0% of transactions random transactions that 00:51:47.220 --> 00:51:49.849 align:start position:0% of transactions random transactions that perhaps<00:51:47.640> will<00:51:48.059> do<00:51:48.839> something<00:51:49.260> that<00:51:49.680> is 00:51:49.849 --> 00:51:49.859 align:start position:0% perhaps will do something that is 00:51:49.859 --> 00:51:52.069 align:start position:0% perhaps will do something that is completely<00:51:50.220> unrelated<00:51:50.819> but<00:51:51.480> what<00:51:51.660> we'll<00:51:51.900> do 00:51:52.069 --> 00:51:52.079 align:start position:0% completely unrelated but what we'll do 00:51:52.079 --> 00:51:54.109 align:start position:0% completely unrelated but what we'll do is<00:51:52.200> input<00:51:52.619> minimization<00:51:53.160> input<00:51:53.700> minimization 00:51:54.109 --> 00:51:54.119 align:start position:0% is input minimization input minimization 00:51:54.119 --> 00:51:56.630 align:start position:0% is input minimization input minimization is<00:51:54.420> a<00:51:54.599> very<00:51:54.720> old<00:51:54.900> technique<00:51:55.520> referred<00:51:56.520> to 00:51:56.630 --> 00:51:56.640 align:start position:0% is a very old technique referred to 00:51:56.640 --> 00:52:01.010 align:start position:0% is a very old technique referred to testing<00:51:57.180> in<00:51:57.960> which<00:51:58.140> you<00:51:58.680> have<00:51:59.059> a<00:52:00.059> list<00:52:00.599> of 00:52:01.010 --> 00:52:01.020 align:start position:0% testing in which you have a list of 00:52:01.020 --> 00:52:05.690 align:start position:0% testing in which you have a list of bytes<00:52:01.920> that<00:52:02.420> affects<00:52:03.420> a<00:52:04.200> bug<00:52:04.619> you<00:52:05.400> want<00:52:05.579> to 00:52:05.690 --> 00:52:05.700 align:start position:0% bytes that affects a bug you want to 00:52:05.700 --> 00:52:08.030 align:start position:0% bytes that affects a bug you want to remove<00:52:06.000> that<00:52:06.359> bytes 00:52:08.030 --> 00:52:08.040 align:start position:0% remove that bytes 00:52:08.040 --> 00:52:11.990 align:start position:0% remove that bytes um<00:52:08.160> one<00:52:08.760> by<00:52:08.940> one<00:52:09.119> or<00:52:09.359> in<00:52:09.660> some<00:52:10.020> random<00:52:10.680> way<00:52:11.000> in 00:52:11.990 --> 00:52:12.000 align:start position:0% um one by one or in some random way in 00:52:12.000 --> 00:52:15.109 align:start position:0% um one by one or in some random way in order<00:52:12.119> to<00:52:12.599> get<00:52:12.960> a 00:52:15.109 --> 00:52:15.119 align:start position:0% order to get a 00:52:15.119 --> 00:52:17.329 align:start position:0% order to get a um a<00:52:15.599> list<00:52:15.960> of<00:52:16.140> bytes<00:52:16.559> that<00:52:16.740> will<00:52:16.980> still 00:52:17.329 --> 00:52:17.339 align:start position:0% um a list of bytes that will still 00:52:17.339 --> 00:52:19.030 align:start position:0% um a list of bytes that will still trigger<00:52:17.700> the<00:52:17.760> bug<00:52:17.940> but<00:52:18.300> it's<00:52:18.420> going<00:52:18.660> to<00:52:18.780> be 00:52:19.030 --> 00:52:19.040 align:start position:0% trigger the bug but it's going to be 00:52:19.040 --> 00:52:22.910 align:start position:0% trigger the bug but it's going to be minimal<00:52:20.040> or<00:52:20.579> or<00:52:21.359> either<00:52:21.780> local<00:52:22.200> or<00:52:22.559> a<00:52:22.680> global 00:52:22.910 --> 00:52:22.920 align:start position:0% minimal or or either local or a global 00:52:22.920 --> 00:52:24.890 align:start position:0% minimal or or either local or a global minimal<00:52:23.400> depending<00:52:23.819> on<00:52:23.940> the<00:52:24.240> type<00:52:24.420> of<00:52:24.599> tool 00:52:24.890 --> 00:52:24.900 align:start position:0% minimal depending on the type of tool 00:52:24.900 --> 00:52:26.569 align:start position:0% minimal depending on the type of tool that<00:52:24.960> you're<00:52:25.200> that<00:52:25.380> yours<00:52:25.740> so<00:52:26.040> in<00:52:26.280> this<00:52:26.400> case 00:52:26.569 --> 00:52:26.579 align:start position:0% that you're that yours so in this case 00:52:26.579 --> 00:52:30.530 align:start position:0% that you're that yours so in this case uh<00:52:27.359> we<00:52:27.720> can<00:52:27.960> uh<00:52:28.559> a<00:52:28.740> kidnap<00:52:29.099> will<00:52:29.400> try<00:52:30.359> to 00:52:30.530 --> 00:52:30.540 align:start position:0% uh we can uh a kidnap will try to 00:52:30.540 --> 00:52:33.829 align:start position:0% uh we can uh a kidnap will try to minimize<00:52:30.960> any<00:52:31.559> any<00:52:32.220> uh<00:52:32.819> parameter<00:52:33.359> here<00:52:33.660> we 00:52:33.829 --> 00:52:33.839 align:start position:0% minimize any any uh parameter here we 00:52:33.839 --> 00:52:35.150 align:start position:0% minimize any any uh parameter here we have<00:52:33.960> only<00:52:34.140> one<00:52:34.380> parameter<00:52:34.859> and<00:52:34.980> the 00:52:35.150 --> 00:52:35.160 align:start position:0% have only one parameter and the 00:52:35.160 --> 00:52:37.730 align:start position:0% have only one parameter and the parameter<00:52:35.579> is<00:52:35.700> actually<00:52:36.020> is<00:52:37.020> actually<00:52:37.260> going 00:52:37.730 --> 00:52:37.740 align:start position:0% parameter is actually is actually going 00:52:37.740 --> 00:52:40.190 align:start position:0% parameter is actually is actually going to<00:52:37.980> be<00:52:38.160> useful<00:52:38.460> triggering<00:52:38.940> about<00:52:39.119> if<00:52:39.960> we<00:52:40.020> have 00:52:40.190 --> 00:52:40.200 align:start position:0% to be useful triggering about if we have 00:52:40.200 --> 00:52:42.049 align:start position:0% to be useful triggering about if we have more<00:52:40.440> parameters<00:52:41.040> they<00:52:41.460> are<00:52:41.640> going<00:52:41.700> to<00:52:41.880> be 00:52:42.049 --> 00:52:42.059 align:start position:0% more parameters they are going to be 00:52:42.059 --> 00:52:44.750 align:start position:0% more parameters they are going to be minimized<00:52:42.720> towards<00:52:43.500> zero<00:52:43.859> so<00:52:44.160> if<00:52:44.460> you<00:52:44.579> have 00:52:44.750 --> 00:52:44.760 align:start position:0% minimized towards zero so if you have 00:52:44.760 --> 00:52:48.049 align:start position:0% minimized towards zero so if you have units<00:52:46.140> uh<00:52:46.859> then<00:52:47.099> it<00:52:47.280> will<00:52:47.400> be<00:52:47.520> reduced<00:52:47.940> until 00:52:48.049 --> 00:52:48.059 align:start position:0% units uh then it will be reduced until 00:52:48.059 --> 00:52:51.230 align:start position:0% units uh then it will be reduced until zero<00:52:48.660> so<00:52:48.839> zero<00:52:49.260> is<00:52:49.380> the<00:52:49.559> simplest 00:52:51.230 --> 00:52:51.240 align:start position:0% zero so zero is the simplest 00:52:51.240 --> 00:52:53.930 align:start position:0% zero so zero is the simplest um<00:52:51.300> uh<00:52:51.780> value<00:52:52.079> this<00:52:52.740> is<00:52:52.859> arbitrary<00:52:53.339> defined<00:52:53.819> on 00:52:53.930 --> 00:52:53.940 align:start position:0% um uh value this is arbitrary defined on 00:52:53.940 --> 00:52:55.970 align:start position:0% um uh value this is arbitrary defined on the<00:52:54.119> uh<00:52:54.420> on<00:52:54.720> the<00:52:54.839> code<00:52:54.960> you<00:52:55.260> can<00:52:55.319> you<00:52:55.559> you<00:52:55.800> can 00:52:55.970 --> 00:52:55.980 align:start position:0% the uh on the code you can you you can 00:52:55.980 --> 00:52:58.849 align:start position:0% the uh on the code you can you you can change<00:52:56.099> it<00:52:56.339> if<00:52:56.520> you<00:52:56.700> want<00:52:57.079> and<00:52:58.079> but<00:52:58.500> in<00:52:58.740> this 00:52:58.849 --> 00:52:58.859 align:start position:0% change it if you want and but in this 00:52:58.859 --> 00:53:00.710 align:start position:0% change it if you want and but in this case<00:52:58.980> the<00:52:59.400> parameter<00:52:59.880> cannot<00:53:00.119> be<00:53:00.300> zero 00:53:00.710 --> 00:53:00.720 align:start position:0% case the parameter cannot be zero 00:53:00.720 --> 00:53:02.930 align:start position:0% case the parameter cannot be zero because<00:53:00.900> if<00:53:01.140> it's<00:53:01.319> zero<00:53:01.740> the<00:53:02.099> the<00:53:02.339> test<00:53:02.640> will 00:53:02.930 --> 00:53:02.940 align:start position:0% because if it's zero the the test will 00:53:02.940 --> 00:53:03.770 align:start position:0% because if it's zero the the test will pass 00:53:03.770 --> 00:53:03.780 align:start position:0% pass 00:53:03.780 --> 00:53:05.150 align:start position:0% pass right 00:53:05.150 --> 00:53:05.160 align:start position:0% right 00:53:05.160 --> 00:53:07.490 align:start position:0% right so<00:53:05.700> in<00:53:06.000> this<00:53:06.180> case<00:53:06.300> the<00:53:06.599> minimal<00:53:06.900> amount<00:53:07.020> is<00:53:07.319> is 00:53:07.490 --> 00:53:07.500 align:start position:0% so in this case the minimal amount is is 00:53:07.500 --> 00:53:09.530 align:start position:0% so in this case the minimal amount is is one<00:53:07.800> it's<00:53:08.160> not<00:53:08.400> guaranteed<00:53:09.000> that<00:53:09.180> you<00:53:09.359> will 00:53:09.530 --> 00:53:09.540 align:start position:0% one it's not guaranteed that you will 00:53:09.540 --> 00:53:13.910 align:start position:0% one it's not guaranteed that you will always<00:53:09.839> get<00:53:10.260> this<00:53:10.740> smallest<00:53:11.960> uh<00:53:12.960> set<00:53:13.440> list<00:53:13.740> of 00:53:13.910 --> 00:53:13.920 align:start position:0% always get this smallest uh set list of 00:53:13.920 --> 00:53:17.329 align:start position:0% always get this smallest uh set list of transactions<00:53:14.520> to<00:53:14.760> trigger<00:53:15.119> uh<00:53:15.960> this<00:53:16.200> is<00:53:16.319> an<00:53:16.859> uh 00:53:17.329 --> 00:53:17.339 align:start position:0% transactions to trigger uh this is an uh 00:53:17.339 --> 00:53:20.510 align:start position:0% transactions to trigger uh this is an uh an<00:53:17.940> MP<00:53:18.240> complete<00:53:18.839> problem<00:53:19.380> it<00:53:19.740> cannot<00:53:20.339> be 00:53:20.510 --> 00:53:20.520 align:start position:0% an MP complete problem it cannot be 00:53:20.520 --> 00:53:23.089 align:start position:0% an MP complete problem it cannot be solved<00:53:20.940> on<00:53:21.000> on<00:53:21.240> linear<00:53:22.140> time<00:53:22.380> so<00:53:22.619> it's<00:53:22.859> it's 00:53:23.089 --> 00:53:23.099 align:start position:0% solved on on linear time so it's it's 00:53:23.099 --> 00:53:25.549 align:start position:0% solved on on linear time so it's it's all<00:53:23.339> going<00:53:23.460> to<00:53:23.640> be<00:53:23.760> always<00:53:23.940> a<00:53:24.300> sample<00:53:24.780> but<00:53:25.380> in 00:53:25.549 --> 00:53:25.559 align:start position:0% all going to be always a sample but in 00:53:25.559 --> 00:53:28.730 align:start position:0% all going to be always a sample but in in<00:53:25.800> practice<00:53:26.400> uh<00:53:27.240> even<00:53:27.780> randomly<00:53:28.319> sampling 00:53:28.730 --> 00:53:28.740 align:start position:0% in practice uh even randomly sampling 00:53:28.740 --> 00:53:31.190 align:start position:0% in practice uh even randomly sampling removing<00:53:29.220> transactions<00:53:30.000> or<00:53:30.240> reducing<00:53:31.020> the 00:53:31.190 --> 00:53:31.200 align:start position:0% removing transactions or reducing the 00:53:31.200 --> 00:53:33.589 align:start position:0% removing transactions or reducing the complexity<00:53:31.619> of<00:53:31.859> each<00:53:32.040> uh<00:53:32.640> value<00:53:33.059> will<00:53:33.359> will 00:53:33.589 --> 00:53:33.599 align:start position:0% complexity of each uh value will will 00:53:33.599 --> 00:53:35.510 align:start position:0% complexity of each uh value will will give<00:53:33.839> you<00:53:33.960> good<00:53:34.260> answers 00:53:35.510 --> 00:53:35.520 align:start position:0% give you good answers 00:53:35.520 --> 00:53:38.750 align:start position:0% give you good answers all<00:53:36.240> right<00:53:36.480> so<00:53:37.200> a<00:53:37.800> little<00:53:37.920> bit<00:53:38.040> about<00:53:38.220> ekina 00:53:38.750 --> 00:53:38.760 align:start position:0% all right so a little bit about ekina 00:53:38.760 --> 00:53:41.329 align:start position:0% all right so a little bit about ekina apis<00:53:39.200> maybe<00:53:40.200> we<00:53:40.380> can<00:53:40.440> just<00:53:40.559> explain 00:53:41.329 --> 00:53:41.339 align:start position:0% apis maybe we can just explain 00:53:41.339 --> 00:53:43.670 align:start position:0% apis maybe we can just explain um yeah<00:53:41.579> just<00:53:42.000> explain<00:53:42.240> why<00:53:42.540> it's<00:53:42.720> happening 00:53:43.670 --> 00:53:43.680 align:start position:0% um yeah just explain why it's happening 00:53:43.680 --> 00:53:44.329 align:start position:0% um yeah just explain why it's happening [Music] 00:53:44.329 --> 00:53:44.339 align:start position:0% [Music] 00:53:44.339 --> 00:53:46.849 align:start position:0% [Music] um 00:53:46.849 --> 00:53:46.859 align:start position:0% 00:53:46.859 --> 00:53:50.290 align:start position:0% yeah<00:53:47.339> so<00:53:47.520> yeah<00:53:47.760> so<00:53:48.119> the<00:53:48.900> issue<00:53:49.260> here<00:53:49.559> is<00:53:49.980> that 00:53:50.290 --> 00:53:50.300 align:start position:0% yeah so yeah so the issue here is that 00:53:50.300 --> 00:53:54.349 align:start position:0% yeah so yeah so the issue here is that if<00:53:51.300> you<00:53:51.420> send<00:53:51.599> one<00:53:52.260> desire<00:53:53.160> token 00:53:54.349 --> 00:53:54.359 align:start position:0% if you send one desire token 00:53:54.359 --> 00:53:56.270 align:start position:0% if you send one desire token what's<00:53:54.839> going<00:53:55.020> to<00:53:55.140> happen<00:53:55.380> is<00:53:55.680> that<00:53:55.859> you<00:53:56.040> do 00:53:56.270 --> 00:53:56.280 align:start position:0% what's going to happen is that you do 00:53:56.280 --> 00:53:58.250 align:start position:0% what's going to happen is that you do one<00:53:56.760> divided<00:53:57.300> by<00:53:57.420> 10 00:53:58.250 --> 00:53:58.260 align:start position:0% one divided by 10 00:53:58.260 --> 00:54:01.670 align:start position:0% one divided by 10 and<00:53:58.680> 1<00:53:59.040> divided<00:53:59.400> by<00:53:59.460> 10<00:53:59.700> is<00:53:59.940> 0<00:54:00.319> because<00:54:01.319> you<00:54:01.559> are 00:54:01.670 --> 00:54:01.680 align:start position:0% and 1 divided by 10 is 0 because you are 00:54:01.680 --> 00:54:04.430 align:start position:0% and 1 divided by 10 is 0 because you are winding<00:54:02.040> down<00:54:02.220> and<00:54:02.579> other<00:54:02.819> results<00:54:03.119> uh<00:54:03.960> the 00:54:04.430 --> 00:54:04.440 align:start position:0% winding down and other results uh the 00:54:04.440 --> 00:54:07.010 align:start position:0% winding down and other results uh the required<00:54:04.920> amount<00:54:05.220> to<00:54:05.579> be<00:54:05.700> sent<00:54:05.819> is<00:54:06.059> zero<00:54:06.359> so<00:54:06.720> if 00:54:07.010 --> 00:54:07.020 align:start position:0% required amount to be sent is zero so if 00:54:07.020 --> 00:54:09.589 align:start position:0% required amount to be sent is zero so if you<00:54:07.200> ask<00:54:07.500> any<00:54:08.160> number<00:54:08.339> of<00:54:08.520> tokens<00:54:08.940> below<00:54:09.359> 10 00:54:09.589 --> 00:54:09.599 align:start position:0% you ask any number of tokens below 10 00:54:09.599 --> 00:54:11.990 align:start position:0% you ask any number of tokens below 10 you<00:54:10.440> are<00:54:10.619> going<00:54:10.680> to<00:54:10.800> get<00:54:10.920> them<00:54:11.099> for<00:54:11.280> free<00:54:11.460> and 00:54:11.990 --> 00:54:12.000 align:start position:0% you are going to get them for free and 00:54:12.000 --> 00:54:14.030 align:start position:0% you are going to get them for free and this<00:54:12.180> is<00:54:12.300> again<00:54:12.839> again<00:54:13.020> an<00:54:13.260> example<00:54:13.559> where<00:54:13.859> we 00:54:14.030 --> 00:54:14.040 align:start position:0% this is again again an example where we 00:54:14.040 --> 00:54:15.589 align:start position:0% this is again again an example where we Define<00:54:14.220> an<00:54:14.460> invariant<00:54:14.940> we<00:54:15.240> don't<00:54:15.359> actually 00:54:15.589 --> 00:54:15.599 align:start position:0% Define an invariant we don't actually 00:54:15.599 --> 00:54:17.930 align:start position:0% Define an invariant we don't actually look<00:54:16.079> at<00:54:16.380> the<00:54:16.619> formula<00:54:17.220> we<00:54:17.400> are<00:54:17.579> not<00:54:17.700> looking 00:54:17.930 --> 00:54:17.940 align:start position:0% look at the formula we are not looking 00:54:17.940 --> 00:54:20.329 align:start position:0% look at the formula we are not looking at<00:54:18.240> how<00:54:18.720> this<00:54:18.960> formula<00:54:19.380> works<00:54:19.680> we<00:54:19.980> just<00:54:20.220> Define 00:54:20.329 --> 00:54:20.339 align:start position:0% at how this formula works we just Define 00:54:20.339 --> 00:54:22.970 align:start position:0% at how this formula works we just Define an<00:54:20.640> invariant<00:54:21.059> that<00:54:21.240> if<00:54:21.839> you<00:54:21.960> don't<00:54:22.079> send<00:54:22.740> ETA 00:54:22.970 --> 00:54:22.980 align:start position:0% an invariant that if you don't send ETA 00:54:22.980 --> 00:54:25.130 align:start position:0% an invariant that if you don't send ETA you<00:54:23.160> should<00:54:23.280> receive<00:54:23.579> not<00:54:23.819> okay<00:54:24.059> and<00:54:24.780> by<00:54:24.960> doing 00:54:25.130 --> 00:54:25.140 align:start position:0% you should receive not okay and by doing 00:54:25.140 --> 00:54:26.930 align:start position:0% you should receive not okay and by doing that<00:54:25.380> akina<00:54:25.980> can<00:54:26.220> find<00:54:26.400> you<00:54:26.520> know<00:54:26.640> how<00:54:26.760> it 00:54:26.930 --> 00:54:26.940 align:start position:0% that akina can find you know how it 00:54:26.940 --> 00:54:29.690 align:start position:0% that akina can find you know how it matching<00:54:27.300> issue<00:54:27.599> and<00:54:28.380> we<00:54:28.740> actually<00:54:28.980> evenly 00:54:29.690 --> 00:54:29.700 align:start position:0% matching issue and we actually evenly 00:54:29.700 --> 00:54:32.349 align:start position:0% matching issue and we actually evenly using<00:54:30.000> Akinator<00:54:30.660> for<00:54:30.839> bonding<00:54:31.680> for<00:54:31.980> you<00:54:32.160> know 00:54:32.349 --> 00:54:32.359 align:start position:0% using Akinator for bonding for you know 00:54:32.359 --> 00:54:35.030 align:start position:0% using Akinator for bonding for you know mistake<00:54:33.359> in<00:54:33.540> the<00:54:33.599> formula<00:54:34.020> and<00:54:34.200> and<00:54:34.440> so<00:54:34.859> on 00:54:35.030 --> 00:54:35.040 align:start position:0% mistake in the formula and and so on 00:54:35.040 --> 00:54:37.010 align:start position:0% mistake in the formula and and so on yeah 00:54:37.010 --> 00:54:37.020 align:start position:0% yeah 00:54:37.020 --> 00:54:39.589 align:start position:0% yeah oh<00:54:37.680> yeah<00:54:37.980> yeah<00:54:38.040> I<00:54:38.700> gave<00:54:38.819> that<00:54:39.000> this<00:54:39.300> function 00:54:39.589 --> 00:54:39.599 align:start position:0% oh yeah yeah I gave that this function 00:54:39.599 --> 00:54:42.049 align:start position:0% oh yeah yeah I gave that this function is<00:54:39.780> for<00:54:40.020> testing<00:54:40.440> purposes<00:54:40.920> but<00:54:41.579> um<00:54:41.640> in<00:54:41.819> a<00:54:41.940> real 00:54:42.049 --> 00:54:42.059 align:start position:0% is for testing purposes but um in a real 00:54:42.059 --> 00:54:44.150 align:start position:0% is for testing purposes but um in a real situation<00:54:42.359> where<00:54:42.660> Cent<00:54:42.960> is<00:54:43.200> not<00:54:43.380> part<00:54:43.619> of<00:54:43.800> the 00:54:44.150 --> 00:54:44.160 align:start position:0% situation where Cent is not part of the 00:54:44.160 --> 00:54:45.890 align:start position:0% situation where Cent is not part of the of<00:54:44.579> the<00:54:44.819> signature<00:54:45.180> of<00:54:45.420> the<00:54:45.480> function<00:54:45.720> right 00:54:45.890 --> 00:54:45.900 align:start position:0% of the signature of the function right 00:54:45.900 --> 00:54:47.990 align:start position:0% of the signature of the function right you<00:54:46.140> read<00:54:46.319> that<00:54:46.500> from<00:54:46.680> the<00:54:46.859> message<00:54:47.040> yeah<00:54:47.819> yeah 00:54:47.990 --> 00:54:48.000 align:start position:0% you read that from the message yeah yeah 00:54:48.000 --> 00:54:50.210 align:start position:0% you read that from the message yeah yeah yeah<00:54:48.119> this<00:54:48.780> is<00:54:48.900> happy<00:54:49.140> like<00:54:49.380> like<00:54:49.559> deeper<00:54:50.099> into 00:54:50.210 --> 00:54:50.220 align:start position:0% yeah this is happy like like deeper into 00:54:50.220 --> 00:54:52.549 align:start position:0% yeah this is happy like like deeper into the<00:54:50.460> code<00:54:50.640> right<00:54:51.059> right<00:54:51.240> so<00:54:52.079> how<00:54:52.319> are<00:54:52.500> you 00:54:52.549 --> 00:54:52.559 align:start position:0% the code right right so how are you 00:54:52.559 --> 00:54:54.890 align:start position:0% the code right right so how are you doing<00:54:52.740> that<00:54:52.920> okay<00:54:53.040> you<00:54:53.280> read<00:54:53.460> that<00:54:53.700> into<00:54:54.240> the<00:54:54.660> a 00:54:54.890 --> 00:54:54.900 align:start position:0% doing that okay you read that into the a 00:54:54.900 --> 00:54:58.010 align:start position:0% doing that okay you read that into the a certain<00:54:55.079> function<00:54:55.559> how<00:54:55.920> you<00:54:56.040> do<00:54:56.220> that<00:54:56.400> so<00:54:56.940> yeah 00:54:58.010 --> 00:54:58.020 align:start position:0% certain function how you do that so yeah 00:54:58.020 --> 00:55:00.470 align:start position:0% certain function how you do that so yeah uh<00:54:58.380> uh<00:54:58.380> if<00:54:58.859> I<00:54:59.040> understand<00:54:59.220> it<00:54:59.579> correctly<00:55:00.000> so 00:55:00.470 --> 00:55:00.480 align:start position:0% uh uh if I understand it correctly so 00:55:00.480 --> 00:55:03.890 align:start position:0% uh uh if I understand it correctly so this<00:55:01.140> this<00:55:01.680> could<00:55:02.160> be<00:55:02.520> an<00:55:02.760> internal<00:55:03.180> part<00:55:03.420> and 00:55:03.890 --> 00:55:03.900 align:start position:0% this this could be an internal part and 00:55:03.900 --> 00:55:05.990 align:start position:0% this this could be an internal part and you<00:55:04.140> can<00:55:04.260> have<00:55:04.440> like<00:55:04.680> a<00:55:05.040> lot<00:55:05.099> of<00:55:05.220> code<00:55:05.400> that<00:55:05.760> put 00:55:05.990 --> 00:55:06.000 align:start position:0% you can have like a lot of code that put 00:55:06.000 --> 00:55:08.809 align:start position:0% you can have like a lot of code that put like<00:55:06.359> gets<00:55:07.140> the<00:55:07.260> value<00:55:07.559> from<00:55:08.099> them<00:55:08.280> from<00:55:08.700> the 00:55:08.809 --> 00:55:08.819 align:start position:0% like gets the value from them from the 00:55:08.819 --> 00:55:10.670 align:start position:0% like gets the value from them from the message<00:55:09.059> value<00:55:09.480> and<00:55:09.839> then<00:55:10.020> do<00:55:10.319> something<00:55:10.500> else 00:55:10.670 --> 00:55:10.680 align:start position:0% message value and then do something else 00:55:10.680 --> 00:55:13.549 align:start position:0% message value and then do something else ah<00:55:11.280> you<00:55:11.400> can<00:55:11.460> do<00:55:11.579> that<00:55:11.760> uh<00:55:12.720> yeah<00:55:12.900> I<00:55:13.079> mean<00:55:13.200> I<00:55:13.440> mean 00:55:13.549 --> 00:55:13.559 align:start position:0% ah you can do that uh yeah I mean I mean 00:55:13.559 --> 00:55:16.069 align:start position:0% ah you can do that uh yeah I mean I mean is<00:55:13.920> this<00:55:14.220> depends<00:55:14.640> on<00:55:14.819> on<00:55:15.059> your<00:55:15.240> code<00:55:15.420> here<00:55:15.720> we 00:55:16.069 --> 00:55:16.079 align:start position:0% is this depends on on your code here we 00:55:16.079 --> 00:55:19.010 align:start position:0% is this depends on on your code here we are<00:55:16.260> testing<00:55:17.040> an<00:55:17.280> internal<00:55:17.700> function<00:55:18.059> right 00:55:19.010 --> 00:55:19.020 align:start position:0% are testing an internal function right 00:55:19.020 --> 00:55:24.349 align:start position:0% are testing an internal function right using<00:55:19.980> using<00:55:20.700> some<00:55:21.000> some<00:55:21.300> defined<00:55:21.960> yeah<00:55:23.160> yeah 00:55:24.349 --> 00:55:24.359 align:start position:0% using using some some defined yeah yeah 00:55:24.359 --> 00:55:26.390 align:start position:0% using using some some defined yeah yeah yeah and<00:55:24.900> if<00:55:25.140> it<00:55:25.440> was<00:55:25.619> using<00:55:25.800> message<00:55:25.980> that 00:55:26.390 --> 00:55:26.400 align:start position:0% yeah and if it was using message that 00:55:26.400 --> 00:55:35.030 align:start position:0% yeah and if it was using message that value<00:55:27.119> um<00:55:27.200> yeah<00:55:28.200> exactly 00:55:35.030 --> 00:55:35.040 align:start position:0% 00:55:35.040 --> 00:55:38.750 align:start position:0% and<00:55:36.000> if<00:55:36.720> you<00:55:36.960> have<00:55:37.140> a<00:55:37.440> constant<00:55:37.859> in<00:55:38.339> your<00:55:38.520> code 00:55:38.750 --> 00:55:38.760 align:start position:0% and if you have a constant in your code 00:55:38.760 --> 00:55:43.130 align:start position:0% and if you have a constant in your code saying<00:55:39.359> message<00:55:39.960> value<00:55:40.319> should<00:55:40.680> be<00:55:41.119> uh<00:55:42.119> 42<00:55:42.599> 42 00:55:43.130 --> 00:55:43.140 align:start position:0% saying message value should be uh 42 42 00:55:43.140 --> 00:55:46.490 align:start position:0% saying message value should be uh 42 42 42<00:55:43.740> it<00:55:44.160> will<00:55:44.460> use<00:55:45.059> that<00:55:45.420> constant<00:55:45.900> eventually 00:55:46.490 --> 00:55:46.500 align:start position:0% 42 it will use that constant eventually 00:55:46.500 --> 00:55:49.069 align:start position:0% 42 it will use that constant eventually so<00:55:46.859> you<00:55:47.160> should<00:55:47.339> be<00:55:47.520> able<00:55:47.640> to<00:55:47.819> hit<00:55:48.180> that 00:55:49.069 --> 00:55:49.079 align:start position:0% so you should be able to hit that 00:55:49.079 --> 00:55:51.950 align:start position:0% so you should be able to hit that particular<00:55:49.440> that<00:55:50.220> particular<00:55:50.579> case<00:55:50.960> given 00:55:51.950 --> 00:55:51.960 align:start position:0% particular that particular case given 00:55:51.960 --> 00:55:53.210 align:start position:0% particular that particular case given the<00:55:52.020> fact<00:55:52.140> that<00:55:52.319> this<00:55:52.500> is<00:55:52.619> random<00:55:53.040> something 00:55:53.210 --> 00:55:53.220 align:start position:0% the fact that this is random something 00:55:53.220 --> 00:55:56.870 align:start position:0% the fact that this is random something of<00:55:53.579> course<00:55:53.940> but<00:55:54.660> can<00:55:54.960> you<00:55:55.260> uh<00:55:55.980> moving<00:55:56.460> back<00:55:56.640> to 00:55:56.870 --> 00:55:56.880 align:start position:0% of course but can you uh moving back to 00:55:56.880 --> 00:55:58.910 align:start position:0% of course but can you uh moving back to the<00:55:57.059> previous<00:55:57.180> slide<00:55:57.540> to<00:55:57.720> the<00:55:57.900> function 00:55:58.910 --> 00:55:58.920 align:start position:0% the previous slide to the function 00:55:58.920 --> 00:56:01.250 align:start position:0% the previous slide to the function what<00:55:59.579> I'm<00:55:59.760> really<00:56:00.119> wondering<00:56:00.599> because<00:56:00.839> we 00:56:01.250 --> 00:56:01.260 align:start position:0% what I'm really wondering because we 00:56:01.260 --> 00:56:04.910 align:start position:0% what I'm really wondering because we talk<00:56:01.500> about<00:56:01.740> this<00:56:02.280> error<00:56:02.640> whoever 00:56:04.910 --> 00:56:04.920 align:start position:0% talk about this error whoever 00:56:04.920 --> 00:56:08.690 align:start position:0% talk about this error whoever tokens<00:56:05.700> less<00:56:06.119> than<00:56:06.540> is<00:56:07.260> uh<00:56:07.859> so<00:56:07.980> way<00:56:08.280> less<00:56:08.520> than 00:56:08.690 --> 00:56:08.700 align:start position:0% tokens less than is uh so way less than 00:56:08.700 --> 00:56:11.150 align:start position:0% tokens less than is uh so way less than it's<00:56:09.000> so<00:56:09.240> small<00:56:09.480> amount<00:56:09.900> and<00:56:10.800> the<00:56:10.980> same 00:56:11.150 --> 00:56:11.160 align:start position:0% it's so small amount and the same 00:56:11.160 --> 00:56:13.990 align:start position:0% it's so small amount and the same problem<00:56:11.400> which<00:56:11.700> could<00:56:12.000> be<00:56:12.180> here<00:56:12.420> is<00:56:13.140> Overflow 00:56:13.990 --> 00:56:14.000 align:start position:0% problem which could be here is Overflow 00:56:14.000 --> 00:56:17.690 align:start position:0% problem which could be here is Overflow if<00:56:15.000> I<00:56:15.420> provide<00:56:15.900> a<00:56:16.200> huge<00:56:16.500> amount<00:56:16.980> of<00:56:17.339> ease 00:56:17.690 --> 00:56:17.700 align:start position:0% if I provide a huge amount of ease 00:56:17.700 --> 00:56:19.370 align:start position:0% if I provide a huge amount of ease because<00:56:17.880> we<00:56:18.180> have<00:56:18.359> a<00:56:18.540> multiplication<00:56:19.079> to 00:56:19.370 --> 00:56:19.380 align:start position:0% because we have a multiplication to 00:56:19.380 --> 00:56:21.770 align:start position:0% because we have a multiplication to decimals<00:56:19.980> it<00:56:20.099> could<00:56:20.280> be<00:56:20.400> done<00:56:20.579> on<00:56:21.420> the<00:56:21.599> other 00:56:21.770 --> 00:56:21.780 align:start position:0% decimals it could be done on the other 00:56:21.780 --> 00:56:25.549 align:start position:0% decimals it could be done on the other side<00:56:22.099> we<00:56:23.099> all<00:56:23.400> of<00:56:23.579> us<00:56:23.700> know<00:56:24.119> that<00:56:24.540> the<00:56:25.200> quantity 00:56:25.549 --> 00:56:25.559 align:start position:0% side we all of us know that the quantity 00:56:25.559 --> 00:56:28.130 align:start position:0% side we all of us know that the quantity of<00:56:25.800> s<00:56:26.099> is<00:56:26.640> limited 00:56:28.130 --> 00:56:28.140 align:start position:0% of s is limited 00:56:28.140 --> 00:56:30.829 align:start position:0% of s is limited you<00:56:29.040> can't<00:56:29.160> even<00:56:29.460> take<00:56:29.700> a<00:56:29.880> flash<00:56:30.059> loan<00:56:30.480> and<00:56:30.599> get 00:56:30.829 --> 00:56:30.839 align:start position:0% you can't even take a flash loan and get 00:56:30.839 --> 00:56:34.309 align:start position:0% you can't even take a flash loan and get more<00:56:31.140> ease<00:56:31.500> than<00:56:31.740> it<00:56:31.920> produce<00:56:32.359> so<00:56:33.359> what<00:56:34.020> is<00:56:34.140> the 00:56:34.309 --> 00:56:34.319 align:start position:0% more ease than it produce so what is the 00:56:34.319 --> 00:56:36.650 align:start position:0% more ease than it produce so what is the best<00:56:34.500> practice<00:56:34.859> follow<00:56:35.579> this<00:56:36.180> formal 00:56:36.650 --> 00:56:36.660 align:start position:0% best practice follow this formal 00:56:36.660 --> 00:56:38.870 align:start position:0% best practice follow this formal execution<00:56:37.260> when<00:56:37.680> you<00:56:37.859> write<00:56:38.040> fuzzing<00:56:38.520> tests 00:56:38.870 --> 00:56:38.880 align:start position:0% execution when you write fuzzing tests 00:56:38.880 --> 00:56:42.290 align:start position:0% execution when you write fuzzing tests or<00:56:39.480> take<00:56:39.720> some<00:56:40.079> real<00:56:40.640> examples<00:56:41.640> as 00:56:42.290 --> 00:56:42.300 align:start position:0% or take some real examples as 00:56:42.300 --> 00:56:45.170 align:start position:0% or take some real examples as limitations<00:56:42.960> as<00:56:43.380> there<00:56:43.559> is<00:56:43.800> no<00:56:44.160> match<00:56:44.520> as 00:56:45.170 --> 00:56:45.180 align:start position:0% limitations as there is no match as 00:56:45.180 --> 00:56:47.450 align:start position:0% limitations as there is no match as zeroom<00:56:45.780> as<00:56:45.960> it<00:56:46.079> exists<00:56:46.440> at<00:56:46.619> the<00:56:46.740> moment<00:56:46.980> and<00:56:47.280> we 00:56:47.450 --> 00:56:47.460 align:start position:0% zeroom as it exists at the moment and we 00:56:47.460 --> 00:56:50.089 align:start position:0% zeroom as it exists at the moment and we know<00:56:47.700> it's<00:56:47.880> a<00:56:48.059> deflation<00:56:48.480> so<00:56:48.780> we<00:56:49.079> can<00:56:49.319> simply 00:56:50.089 --> 00:56:50.099 align:start position:0% know it's a deflation so we can simply 00:56:50.099 --> 00:56:52.970 align:start position:0% know it's a deflation so we can simply assume<00:56:51.000> that<00:56:51.240> in<00:56:51.780> the<00:56:51.900> future<00:56:52.020> nobody<00:56:52.619> could 00:56:52.970 --> 00:56:52.980 align:start position:0% assume that in the future nobody could 00:56:52.980 --> 00:56:55.250 align:start position:0% assume that in the future nobody could take<00:56:53.220> so<00:56:53.520> much<00:56:53.640> to<00:56:53.880> get<00:56:54.059> overflow<00:56:54.540> here<00:56:54.780> yeah 00:56:55.250 --> 00:56:55.260 align:start position:0% take so much to get overflow here yeah 00:56:55.260 --> 00:56:57.410 align:start position:0% take so much to get overflow here yeah yeah exactly<00:56:55.980> so<00:56:56.339> yeah<00:56:56.579> this<00:56:56.819> is<00:56:56.940> is<00:56:57.180> an 00:56:57.410 --> 00:56:57.420 align:start position:0% yeah exactly so yeah this is is an 00:56:57.420 --> 00:57:00.290 align:start position:0% yeah exactly so yeah this is is an interesting<00:56:57.780> question<00:56:58.160> and<00:56:59.160> it<00:56:59.579> goes<00:56:59.940> into 00:57:00.290 --> 00:57:00.300 align:start position:0% interesting question and it goes into 00:57:00.300 --> 00:57:02.329 align:start position:0% interesting question and it goes into the<00:57:00.780> fact<00:57:00.960> that<00:57:01.200> what<00:57:01.559> are<00:57:01.680> your<00:57:01.920> assumptions 00:57:02.329 --> 00:57:02.339 align:start position:0% the fact that what are your assumptions 00:57:02.339 --> 00:57:05.030 align:start position:0% the fact that what are your assumptions on<00:57:02.819> the<00:57:02.940> test<00:57:03.180> right<00:57:03.900> if<00:57:04.440> you<00:57:04.559> if<00:57:04.800> your 00:57:05.030 --> 00:57:05.040 align:start position:0% on the test right if you if your 00:57:05.040 --> 00:57:07.609 align:start position:0% on the test right if you if your assumptions<00:57:05.460> are<00:57:05.700> like<00:57:06.000> I<00:57:06.540> have<00:57:06.720> this<00:57:07.200> token 00:57:07.609 --> 00:57:07.619 align:start position:0% assumptions are like I have this token 00:57:07.619 --> 00:57:09.770 align:start position:0% assumptions are like I have this token with<00:57:07.859> this<00:57:08.099> limited<00:57:08.520> Supply<00:57:08.760> that<00:57:09.480> should 00:57:09.770 --> 00:57:09.780 align:start position:0% with this limited Supply that should 00:57:09.780 --> 00:57:13.010 align:start position:0% with this limited Supply that should never<00:57:09.960> go<00:57:10.319> over<00:57:10.500> something<00:57:11.180> then<00:57:12.180> you<00:57:12.540> you<00:57:12.780> can 00:57:13.010 --> 00:57:13.020 align:start position:0% never go over something then you you can 00:57:13.020 --> 00:57:16.250 align:start position:0% never go over something then you you can just<00:57:13.140> say<00:57:13.440> I<00:57:13.920> require<00:57:14.160> that<00:57:14.900> that<00:57:15.900> the<00:57:16.140> value 00:57:16.250 --> 00:57:16.260 align:start position:0% just say I require that that the value 00:57:16.260 --> 00:57:18.230 align:start position:0% just say I require that that the value sign<00:57:16.619> cannot<00:57:17.220> be<00:57:17.400> more<00:57:17.640> than<00:57:17.819> the<00:57:18.000> total 00:57:18.230 --> 00:57:18.240 align:start position:0% sign cannot be more than the total 00:57:18.240 --> 00:57:20.690 align:start position:0% sign cannot be more than the total supply<00:57:18.420> of<00:57:18.780> something<00:57:18.960> right<00:57:19.859> but<00:57:20.400> in<00:57:20.579> the 00:57:20.690 --> 00:57:20.700 align:start position:0% supply of something right but in the 00:57:20.700 --> 00:57:22.730 align:start position:0% supply of something right but in the case<00:57:20.819> of<00:57:20.940> interest<00:57:21.180> is<00:57:21.720> a<00:57:21.839> bit<00:57:22.020> more<00:57:22.319> tricky 00:57:22.730 --> 00:57:22.740 align:start position:0% case of interest is a bit more tricky 00:57:22.740 --> 00:57:26.390 align:start position:0% case of interest is a bit more tricky and<00:57:23.460> and<00:57:23.700> in<00:57:24.000> fact<00:57:24.180> in<00:57:24.839> in<00:57:25.079> Echidna<00:57:25.920> what<00:57:26.099> we<00:57:26.220> do 00:57:26.390 --> 00:57:26.400 align:start position:0% and and in fact in in Echidna what we do 00:57:26.400 --> 00:57:29.150 align:start position:0% and and in fact in in Echidna what we do is<00:57:26.579> we<00:57:27.359> have<00:57:27.540> we<00:57:27.900> have<00:57:28.260> externally<00:57:28.920> on 00:57:29.150 --> 00:57:29.160 align:start position:0% is we have we have externally on 00:57:29.160 --> 00:57:31.549 align:start position:0% is we have we have externally on accounts<00:57:29.640> that<00:57:29.700> are<00:57:29.819> simulated<00:57:30.300> we<00:57:31.079> loaded 00:57:31.549 --> 00:57:31.559 align:start position:0% accounts that are simulated we loaded 00:57:31.559 --> 00:57:33.410 align:start position:0% accounts that are simulated we loaded with<00:57:31.800> eater<00:57:32.280> every<00:57:32.579> at<00:57:32.819> every<00:57:33.000> transaction 00:57:33.410 --> 00:57:33.420 align:start position:0% with eater every at every transaction 00:57:33.420 --> 00:57:36.170 align:start position:0% with eater every at every transaction because<00:57:34.200> you<00:57:34.500> can<00:57:34.680> have<00:57:34.980> a<00:57:35.579> very<00:57:35.640> large<00:57:35.880> amount 00:57:36.170 --> 00:57:36.180 align:start position:0% because you can have a very large amount 00:57:36.180 --> 00:57:39.230 align:start position:0% because you can have a very large amount of<00:57:36.300> feature<00:57:36.660> you<00:57:36.960> can<00:57:37.079> take<00:57:37.500> a<00:57:37.680> flat<00:57:37.980> loan<00:57:38.339> uh 00:57:39.230 --> 00:57:39.240 align:start position:0% of feature you can take a flat loan uh 00:57:39.240 --> 00:57:42.410 align:start position:0% of feature you can take a flat loan uh you<00:57:39.420> you<00:57:39.720> probably<00:57:40.020> cannot<00:57:40.680> have<00:57:41.160> as<00:57:41.700> enough 00:57:42.410 --> 00:57:42.420 align:start position:0% you you probably cannot have as enough 00:57:42.420 --> 00:57:46.849 align:start position:0% you you probably cannot have as enough eater<00:57:43.079> to<00:57:43.440> overflow<00:57:44.280> uh<00:57:45.119> you<00:57:45.300> into<00:57:45.859> 256 00:57:46.849 --> 00:57:46.859 align:start position:0% eater to overflow uh you into 256 00:57:46.859 --> 00:57:49.970 align:start position:0% eater to overflow uh you into 256 because<00:57:47.220> that<00:57:47.640> will<00:57:47.880> be<00:57:48.140> a<00:57:49.140> real<00:57:49.260> issue<00:57:49.740> for 00:57:49.970 --> 00:57:49.980 align:start position:0% because that will be a real issue for 00:57:49.980 --> 00:57:53.990 align:start position:0% because that will be a real issue for the<00:57:50.160> AVM<00:57:50.640> uh<00:57:51.540> in<00:57:51.780> in<00:57:51.900> itself<00:57:52.260> but 00:57:53.990 --> 00:57:54.000 align:start position:0% the AVM uh in in itself but 00:57:54.000 --> 00:57:56.630 align:start position:0% the AVM uh in in itself but um<00:57:54.059> we<00:57:54.660> can<00:57:54.780> we<00:57:55.020> can<00:57:55.200> Define<00:57:55.380> in<00:57:56.040> the<00:57:56.160> Kinder 00:57:56.630 --> 00:57:56.640 align:start position:0% um we can we can Define in the Kinder 00:57:56.640 --> 00:57:59.150 align:start position:0% um we can we can Define in the Kinder config<00:57:57.000> which<00:57:57.599> is<00:57:57.780> the<00:57:58.079> maximum<00:57:58.619> amount<00:57:58.980> of 00:57:59.150 --> 00:57:59.160 align:start position:0% config which is the maximum amount of 00:57:59.160 --> 00:58:02.150 align:start position:0% config which is the maximum amount of value<00:57:59.520> that<00:57:59.940> we<00:58:00.119> send<00:58:00.359> per<00:58:00.839> transaction<00:58:01.319> right 00:58:02.150 --> 00:58:02.160 align:start position:0% value that we send per transaction right 00:58:02.160 --> 00:58:04.490 align:start position:0% value that we send per transaction right so<00:58:02.400> if<00:58:02.579> you<00:58:02.640> put<00:58:02.819> like<00:58:03.059> I<00:58:03.599> don't<00:58:03.780> care<00:58:04.020> if<00:58:04.319> the 00:58:04.490 --> 00:58:04.500 align:start position:0% so if you put like I don't care if the 00:58:04.500 --> 00:58:07.490 align:start position:0% so if you put like I don't care if the attacker<00:58:04.859> has<00:58:05.040> more<00:58:05.400> than<00:58:05.579> than<00:58:06.359> 10<00:58:07.020> 000<00:58:07.079> liter 00:58:07.490 --> 00:58:07.500 align:start position:0% attacker has more than than 10 000 liter 00:58:07.500 --> 00:58:10.190 align:start position:0% attacker has more than than 10 000 liter because<00:58:08.160> that<00:58:08.760> will<00:58:08.940> mean<00:58:09.240> that<00:58:09.599> they<00:58:09.839> can<00:58:10.020> do 00:58:10.190 --> 00:58:10.200 align:start position:0% because that will mean that they can do 00:58:10.200 --> 00:58:13.490 align:start position:0% because that will mean that they can do other<00:58:10.319> things<00:58:10.700> then<00:58:11.700> Echidna<00:58:12.359> will<00:58:12.599> happily 00:58:13.490 --> 00:58:13.500 align:start position:0% other things then Echidna will happily 00:58:13.500 --> 00:58:15.710 align:start position:0% other things then Echidna will happily uh<00:58:14.099> take<00:58:14.400> that<00:58:14.579> limit<00:58:14.760> and<00:58:15.059> will<00:58:15.240> never<00:58:15.420> put 00:58:15.710 --> 00:58:15.720 align:start position:0% uh take that limit and will never put 00:58:15.720 --> 00:58:18.530 align:start position:0% uh take that limit and will never put something<00:58:16.020> more<00:58:16.400> however<00:58:17.400> it's<00:58:18.119> still<00:58:18.300> the 00:58:18.530 --> 00:58:18.540 align:start position:0% something more however it's still the 00:58:18.540 --> 00:58:20.870 align:start position:0% something more however it's still the case<00:58:18.720> that<00:58:19.140> over<00:58:19.680> several<00:58:20.280> number<00:58:20.760> of 00:58:20.870 --> 00:58:20.880 align:start position:0% case that over several number of 00:58:20.880 --> 00:58:22.790 align:start position:0% case that over several number of transactions<00:58:21.480> the<00:58:21.780> accumulate<00:58:22.380> number<00:58:22.559> of 00:58:22.790 --> 00:58:22.800 align:start position:0% transactions the accumulate number of 00:58:22.800 --> 00:58:25.370 align:start position:0% transactions the accumulate number of features<00:58:23.280> can<00:58:24.000> go<00:58:24.180> over<00:58:24.300> that<00:58:24.660> that<00:58:24.960> barrier 00:58:25.370 --> 00:58:25.380 align:start position:0% features can go over that that barrier 00:58:25.380 --> 00:58:26.750 align:start position:0% features can go over that that barrier so<00:58:25.500> you<00:58:25.740> should<00:58:25.859> you<00:58:26.040> should<00:58:26.220> be<00:58:26.339> careful<00:58:26.579> with 00:58:26.750 --> 00:58:26.760 align:start position:0% so you should you should be careful with 00:58:26.760 --> 00:58:28.849 align:start position:0% so you should you should be careful with it<00:58:26.940> and<00:58:27.059> there<00:58:27.660> is<00:58:27.780> also<00:58:27.900> no<00:58:27.960> project<00:58:28.200> you<00:58:28.680> can 00:58:28.849 --> 00:58:28.859 align:start position:0% it and there is also no project you can 00:58:28.859 --> 00:58:30.829 align:start position:0% it and there is also no project you can take<00:58:28.980> here<00:58:29.280> so<00:58:29.819> basically<00:58:30.240> you<00:58:30.540> are<00:58:30.720> building 00:58:30.829 --> 00:58:30.839 align:start position:0% take here so basically you are building 00:58:30.839 --> 00:58:32.809 align:start position:0% take here so basically you are building an<00:58:31.020> invariant<00:58:31.500> and<00:58:31.800> the<00:58:31.980> invariant<00:58:32.400> of<00:58:32.579> which 00:58:32.809 --> 00:58:32.819 align:start position:0% an invariant and the invariant of which 00:58:32.819 --> 00:58:35.329 align:start position:0% an invariant and the invariant of which we<00:58:33.059> thought<00:58:33.180> as<00:58:33.420> like<00:58:33.660> a<00:58:33.780> value 00:58:35.329 --> 00:58:35.339 align:start position:0% we thought as like a value 00:58:35.339 --> 00:58:39.289 align:start position:0% we thought as like a value so<00:58:35.960> either<00:58:36.960> you<00:58:37.559> start<00:58:37.799> where<00:58:38.460> the<00:58:38.819> invariant 00:58:39.289 --> 00:58:39.299 align:start position:0% so either you start where the invariant 00:58:39.299 --> 00:58:41.930 align:start position:0% so either you start where the invariant has<00:58:39.599> really<00:58:40.099> limited<00:58:41.099> Twitter<00:58:41.400> like<00:58:41.819> really 00:58:41.930 --> 00:58:41.940 align:start position:0% has really limited Twitter like really 00:58:41.940 --> 00:58:44.210 align:start position:0% has really limited Twitter like really with<00:58:42.240> chain<00:58:42.540> one<00:58:42.780> and<00:58:43.260> you<00:58:43.440> try<00:58:43.619> to<00:58:43.799> see<00:58:43.980> if<00:58:44.099> it 00:58:44.210 --> 00:58:44.220 align:start position:0% with chain one and you try to see if it 00:58:44.220 --> 00:58:46.309 align:start position:0% with chain one and you try to see if it hurts<00:58:44.640> if<00:58:45.059> it's<00:58:45.180> working<00:58:45.420> with<00:58:45.780> like<00:58:46.020> a<00:58:46.140> you 00:58:46.309 --> 00:58:46.319 align:start position:0% hurts if it's working with like a you 00:58:46.319 --> 00:58:48.349 align:start position:0% hurts if it's working with like a you know<00:58:46.440> like<00:58:46.619> with<00:58:47.280> one<00:58:47.460> meter<00:58:47.760> okay<00:58:48.119> it's 00:58:48.349 --> 00:58:48.359 align:start position:0% know like with one meter okay it's 00:58:48.359 --> 00:58:49.849 align:start position:0% know like with one meter okay it's already<00:58:48.480> working<00:58:48.780> so<00:58:49.079> you<00:58:49.200> can<00:58:49.319> continue<00:58:49.440> like 00:58:49.849 --> 00:58:49.859 align:start position:0% already working so you can continue like 00:58:49.859 --> 00:58:51.410 align:start position:0% already working so you can continue like this<00:58:49.980> if<00:58:50.280> it's<00:58:50.460> not<00:58:50.579> breaking<00:58:50.940> then<00:58:51.119> you<00:58:51.299> can 00:58:51.410 --> 00:58:51.420 align:start position:0% this if it's not breaking then you can 00:58:51.420 --> 00:58:53.270 align:start position:0% this if it's not breaking then you can increase<00:58:51.720> this<00:58:52.140> with<00:58:52.440> time<00:58:52.859> from<00:58:53.040> time<00:58:53.160> to 00:58:53.270 --> 00:58:53.280 align:start position:0% increase this with time from time to 00:58:53.280 --> 00:58:54.829 align:start position:0% increase this with time from time to time<00:58:53.520> or<00:58:54.059> you<00:58:54.180> can<00:58:54.299> take<00:58:54.359> the<00:58:54.540> opposite 00:58:54.829 --> 00:58:54.839 align:start position:0% time or you can take the opposite 00:58:54.839 --> 00:58:56.270 align:start position:0% time or you can take the opposite approach<00:58:55.200> if<00:58:55.319> you<00:58:55.440> define<00:58:55.559> an<00:58:55.799> invariant 00:58:56.270 --> 00:58:56.280 align:start position:0% approach if you define an invariant 00:58:56.280 --> 00:58:58.910 align:start position:0% approach if you define an invariant where<00:58:56.579> the<00:58:57.359> threshold<00:58:57.720> is<00:58:57.900> really<00:58:58.079> large 00:58:58.910 --> 00:58:58.920 align:start position:0% where the threshold is really large 00:58:58.920 --> 00:59:00.589 align:start position:0% where the threshold is really large it's<00:58:59.400> working<00:58:59.640> because<00:58:59.940> it's<00:59:00.180> really<00:59:00.359> large 00:59:00.589 --> 00:59:00.599 align:start position:0% it's working because it's really large 00:59:00.599 --> 00:59:02.750 align:start position:0% it's working because it's really large and<00:59:00.839> then<00:59:00.960> you<00:59:01.200> decrease<00:59:01.500> this<00:59:01.980> result<00:59:02.220> so 00:59:02.750 --> 00:59:02.760 align:start position:0% and then you decrease this result so 00:59:02.760 --> 00:59:04.549 align:start position:0% and then you decrease this result so that's<00:59:02.819> how<00:59:03.000> you<00:59:03.180> start<00:59:03.420> really<00:59:03.780> limited<00:59:04.260> and 00:59:04.549 --> 00:59:04.559 align:start position:0% that's how you start really limited and 00:59:04.559 --> 00:59:06.530 align:start position:0% that's how you start really limited and you<00:59:04.799> know<00:59:04.859> depending<00:59:05.220> on<00:59:05.339> the<00:59:05.460> result<00:59:05.579> you 00:59:06.530 --> 00:59:06.540 align:start position:0% you know depending on the result you 00:59:06.540 --> 00:59:08.150 align:start position:0% you know depending on the result you remove<00:59:06.780> the<00:59:07.020> limitation<00:59:07.440> or<00:59:07.799> you<00:59:07.920> start 00:59:08.150 --> 00:59:08.160 align:start position:0% remove the limitation or you start 00:59:08.160 --> 00:59:10.789 align:start position:0% remove the limitation or you start without<00:59:08.400> limitation<00:59:09.000> and<00:59:09.480> you<00:59:09.599> reduce<00:59:09.839> like 00:59:10.789 --> 00:59:10.799 align:start position:0% without limitation and you reduce like 00:59:10.799 --> 00:59:13.430 align:start position:0% without limitation and you reduce like up<00:59:11.460> up<00:59:11.819> to<00:59:12.119> the<00:59:12.240> point<00:59:12.359> where<00:59:12.599> you<00:59:12.839> have<00:59:12.960> a<00:59:13.200> kind 00:59:13.430 --> 00:59:13.440 align:start position:0% up up to the point where you have a kind 00:59:13.440 --> 00:59:15.470 align:start position:0% up up to the point where you have a kind of<00:59:13.559> like<00:59:13.680> a<00:59:14.040> value<00:59:14.700> for<00:59:14.940> which<00:59:15.180> you<00:59:15.299> feel 00:59:15.470 --> 00:59:15.480 align:start position:0% of like a value for which you feel 00:59:15.480 --> 00:59:17.450 align:start position:0% of like a value for which you feel comfortable<00:59:15.900> with<00:59:16.140> yeah<00:59:16.500> yeah<00:59:16.619> and<00:59:16.920> and<00:59:17.040> that 00:59:17.450 --> 00:59:17.460 align:start position:0% comfortable with yeah yeah and and that 00:59:17.460 --> 00:59:23.450 align:start position:0% comfortable with yeah yeah and and that is<00:59:17.640> also<00:59:17.819> related<00:59:18.059> with 00:59:23.450 --> 00:59:23.460 align:start position:0% 00:59:23.460 --> 00:59:25.549 align:start position:0% the if<00:59:24.059> we<00:59:24.240> start<00:59:24.420> with<00:59:24.660> very<00:59:24.900> large<00:59:25.079> values 00:59:25.549 --> 00:59:25.559 align:start position:0% the if we start with very large values 00:59:25.559 --> 00:59:28.789 align:start position:0% the if we start with very large values we<00:59:26.040> we<00:59:26.339> could<00:59:26.520> have<00:59:26.760> false<00:59:27.119> positives<00:59:27.540> but<00:59:28.260> and 00:59:28.789 --> 00:59:28.799 align:start position:0% we we could have false positives but and 00:59:28.799 --> 00:59:30.410 align:start position:0% we we could have false positives but and if<00:59:28.920> we<00:59:29.099> start<00:59:29.220> with<00:59:29.400> very<00:59:29.579> small<00:59:29.760> values<00:59:30.119> we 00:59:30.410 --> 00:59:30.420 align:start position:0% if we start with very small values we 00:59:30.420 --> 00:59:32.690 align:start position:0% if we start with very small values we can<00:59:30.540> have<00:59:30.720> a<00:59:30.960> false<00:59:31.559> negative<00:59:31.859> but<00:59:32.220> which<00:59:32.460> are 00:59:32.690 --> 00:59:32.700 align:start position:0% can have a false negative but which are 00:59:32.700 --> 00:59:34.430 align:start position:0% can have a false negative but which are the<00:59:32.880> ones<00:59:33.180> that<00:59:33.660> are<00:59:33.780> going<00:59:33.900> to<00:59:34.020> cause<00:59:34.200> you 00:59:34.430 --> 00:59:34.440 align:start position:0% the ones that are going to cause you 00:59:34.440 --> 00:59:36.710 align:start position:0% the ones that are going to cause you more<00:59:34.680> trouble<00:59:34.920> that<00:59:35.760> is<00:59:35.880> something<00:59:36.059> to<00:59:36.480> to 00:59:36.710 --> 00:59:36.720 align:start position:0% more trouble that is something to to 00:59:36.720 --> 00:59:39.349 align:start position:0% more trouble that is something to to think<00:59:37.020> about<00:59:37.260> it<00:59:37.500> because<00:59:37.680> if<00:59:38.099> you<00:59:38.280> miss<00:59:38.520> one's 00:59:39.349 --> 00:59:39.359 align:start position:0% think about it because if you miss one's 00:59:39.359 --> 00:59:42.530 align:start position:0% think about it because if you miss one's false<00:59:39.660> positive<00:59:40.020> your<00:59:40.920> your<00:59:41.280> protocol<00:59:41.700> can<00:59:42.240> be 00:59:42.530 --> 00:59:42.540 align:start position:0% false positive your your protocol can be 00:59:42.540 --> 00:59:45.470 align:start position:0% false positive your your protocol can be you<00:59:43.200> know<00:59:43.260> destroyed<00:59:43.920> and<00:59:44.339> if<00:59:44.640> you<00:59:44.760> miss<00:59:45.000> one 00:59:45.470 --> 00:59:45.480 align:start position:0% you know destroyed and if you miss one 00:59:45.480 --> 00:59:48.770 align:start position:0% you know destroyed and if you miss one one<00:59:45.720> false<00:59:46.140> negative<00:59:46.500> then<00:59:46.859> it's<00:59:47.099> okay 00:59:48.770 --> 00:59:48.780 align:start position:0% one false negative then it's okay 00:59:48.780 --> 00:59:50.710 align:start position:0% one false negative then it's okay all<00:59:49.380> right 00:59:50.710 --> 00:59:50.720 align:start position:0% all right 00:59:50.720 --> 00:59:53.809 align:start position:0% all right hey<00:59:51.720> there<00:59:51.960> in<00:59:52.559> terms<00:59:52.799> of<00:59:52.859> fuzzing<00:59:53.400> mutation 00:59:53.809 --> 00:59:53.819 align:start position:0% hey there in terms of fuzzing mutation 00:59:53.819 --> 00:59:57.230 align:start position:0% hey there in terms of fuzzing mutation uh<00:59:54.599> do<00:59:54.780> you<00:59:54.960> do<00:59:55.020> any<00:59:55.200> clever<00:59:55.559> things<00:59:55.859> like<00:59:56.460> uh 00:59:57.230 --> 00:59:57.240 align:start position:0% uh do you do any clever things like uh 00:59:57.240 --> 00:59:59.930 align:start position:0% uh do you do any clever things like uh say<00:59:57.480> this<00:59:57.720> function<00:59:58.020> has<00:59:58.500> a<00:59:58.980> constant<00:59:59.460> of<00:59:59.700> 10 00:59:59.930 --> 00:59:59.940 align:start position:0% say this function has a constant of 10 00:59:59.940 --> 01:00:03.589 align:start position:0% say this function has a constant of 10 so<01:00:00.720> would<01:00:01.020> you<01:00:01.200> then<01:00:01.640> uh<01:00:02.640> see<01:00:02.940> the<01:00:03.180> constants 01:00:03.589 --> 01:00:03.599 align:start position:0% so would you then uh see the constants 01:00:03.599 --> 01:00:06.109 align:start position:0% so would you then uh see the constants in<01:00:04.140> the<01:00:04.619> the<01:00:04.859> function<01:00:05.220> and<01:00:05.579> use<01:00:05.760> that<01:00:05.940> as 01:00:06.109 --> 01:00:06.119 align:start position:0% in the the function and use that as 01:00:06.119 --> 01:00:08.270 align:start position:0% in the the function and use that as input<01:00:06.480> yeah<01:00:06.900> we<01:00:07.200> reuse<01:00:07.619> the<01:00:07.799> constant<01:00:07.980> forms 01:00:08.270 --> 01:00:08.280 align:start position:0% input yeah we reuse the constant forms 01:00:08.280 --> 01:00:10.190 align:start position:0% input yeah we reuse the constant forms of<01:00:08.339> function<01:00:08.579> and<01:00:08.880> we<01:00:09.059> will<01:00:09.180> first<01:00:09.480> I<01:00:09.900> want<01:00:10.020> the 01:00:10.190 --> 01:00:10.200 align:start position:0% of function and we will first I want the 01:00:10.200 --> 01:00:12.289 align:start position:0% of function and we will first I want the constant<01:00:10.500> also<01:00:10.859> like<01:00:11.220> if<01:00:11.400> you<01:00:11.579> see<01:00:11.760> 10<01:00:11.940> we<01:00:12.180> are 01:00:12.289 --> 01:00:12.299 align:start position:0% constant also like if you see 10 we are 01:00:12.299 --> 01:00:14.450 align:start position:0% constant also like if you see 10 we are going<01:00:12.420> to<01:00:12.480> use<01:00:12.599> 10<01:00:12.839> we<01:00:13.140> are<01:00:13.260> going<01:00:13.319> to<01:00:13.440> use<01:00:13.619> 9<01:00:13.920> 11 01:00:14.450 --> 01:00:14.460 align:start position:0% going to use 10 we are going to use 9 11 01:00:14.460 --> 01:00:18.890 align:start position:0% going to use 10 we are going to use 9 11 and<01:00:15.059> you<01:00:15.299> know<01:00:15.359> like<01:00:15.540> uh<01:00:16.140> around 01:00:18.890 --> 01:00:18.900 align:start position:0% 01:00:18.900 --> 01:00:21.770 align:start position:0% uh<01:00:19.559> yes<01:00:20.160> there<01:00:20.579> are<01:00:20.760> some<01:00:20.940> there<01:00:21.359> are<01:00:21.480> some 01:00:21.770 --> 01:00:21.780 align:start position:0% uh yes there are some there are some 01:00:21.780 --> 01:00:24.309 align:start position:0% uh yes there are some there are some techniques<01:00:22.559> I<01:00:22.740> can<01:00:22.920> show<01:00:23.099> you<01:00:23.280> a<01:00:23.520> little<01:00:23.640> bit 01:00:24.309 --> 01:00:24.319 align:start position:0% techniques I can show you a little bit 01:00:24.319 --> 01:00:27.950 align:start position:0% techniques I can show you a little bit after<01:00:25.319> a<01:00:25.980> few<01:00:26.160> lines<01:00:26.880> of<01:00:27.119> the<01:00:27.359> code<01:00:27.540> of 01:00:27.950 --> 01:00:27.960 align:start position:0% after a few lines of the code of 01:00:27.960 --> 01:00:30.410 align:start position:0% after a few lines of the code of Akinator<01:00:28.559> that<01:00:28.680> shows<01:00:28.980> all<01:00:29.040> limitations<01:00:29.520> we 01:00:30.410 --> 01:00:30.420 align:start position:0% Akinator that shows all limitations we 01:00:30.420 --> 01:00:32.630 align:start position:0% Akinator that shows all limitations we have<01:00:30.660> mutation<01:00:31.260> interesting<01:00:31.680> mutations<01:00:32.099> on 01:00:32.630 --> 01:00:32.640 align:start position:0% have mutation interesting mutations on 01:00:32.640 --> 01:00:34.510 align:start position:0% have mutation interesting mutations on list<01:00:32.940> of<01:00:33.059> transactions<01:00:33.599> in<01:00:33.720> which<01:00:33.900> we<01:00:34.140> Shuffle 01:00:34.510 --> 01:00:34.520 align:start position:0% list of transactions in which we Shuffle 01:00:34.520 --> 01:00:37.809 align:start position:0% list of transactions in which we Shuffle we<01:00:35.520> do<01:00:35.700> uh<01:00:36.420> we<01:00:36.720> do<01:00:36.839> like 01:00:37.809 --> 01:00:37.819 align:start position:0% we do uh we do like 01:00:37.819 --> 01:00:41.690 align:start position:0% we do uh we do like splice<01:00:38.819> as<01:00:39.059> well<01:00:39.180> so<01:00:39.420> we<01:00:39.660> take<01:00:39.900> a<01:00:40.799> list<01:00:41.160> a<01:00:41.520> list 01:00:41.690 --> 01:00:41.700 align:start position:0% splice as well so we take a list a list 01:00:41.700 --> 01:00:43.609 align:start position:0% splice as well so we take a list a list of<01:00:41.819> Interest<01:00:41.940> transaction<01:00:42.599> and<01:00:43.079> another<01:00:43.260> one 01:00:43.609 --> 01:00:43.619 align:start position:0% of Interest transaction and another one 01:00:43.619 --> 01:00:46.430 align:start position:0% of Interest transaction and another one and<01:00:43.980> we<01:00:44.220> splice<01:00:44.700> it<01:00:44.880> on<01:00:45.180> a<01:00:45.359> random<01:00:45.540> position<01:00:45.780> so 01:00:46.430 --> 01:00:46.440 align:start position:0% and we splice it on a random position so 01:00:46.440 --> 01:00:48.470 align:start position:0% and we splice it on a random position so there<01:00:46.619> are<01:00:46.740> a<01:00:46.980> couple<01:00:47.099> of<01:00:47.220> fun<01:00:47.640> things<01:00:47.940> to<01:00:48.240> to 01:00:48.470 --> 01:00:48.480 align:start position:0% there are a couple of fun things to to 01:00:48.480 --> 01:00:50.750 align:start position:0% there are a couple of fun things to to look<01:00:48.720> at<01:00:48.900> but<01:00:49.260> uh<01:00:49.740> yeah<01:00:49.980> I<01:00:50.160> think<01:00:50.280> we<01:00:50.579> should 01:00:50.750 --> 01:00:50.760 align:start position:0% look at but uh yeah I think we should 01:00:50.760 --> 01:00:52.789 align:start position:0% look at but uh yeah I think we should move<01:00:51.480> on<01:00:51.660> a<01:00:51.839> little<01:00:51.960> bit 01:00:52.789 --> 01:00:52.799 align:start position:0% move on a little bit 01:00:52.799 --> 01:00:56.089 align:start position:0% move on a little bit um<01:00:52.859> all<01:00:53.280> right<01:00:53.460> so<01:00:54.359> as<01:00:54.720> I<01:00:54.900> was<01:00:55.079> saying<01:00:55.440> we<01:00:55.920> have 01:00:56.089 --> 01:00:56.099 align:start position:0% um all right so as I was saying we have 01:00:56.099 --> 01:00:58.490 align:start position:0% um all right so as I was saying we have this<01:00:56.520> uh<01:00:56.880> failing<01:00:57.359> even<01:00:57.900> if<01:00:58.140> you<01:00:58.319> don't 01:00:58.490 --> 01:00:58.500 align:start position:0% this uh failing even if you don't 01:00:58.500 --> 01:01:02.150 align:start position:0% this uh failing even if you don't understand<01:00:58.799> what<01:00:59.700> was<01:00:59.880> what<01:01:00.299> is<01:01:00.420> the<01:01:00.599> failure 01:01:02.150 --> 01:01:02.160 align:start position:0% understand what was what is the failure 01:01:02.160 --> 01:01:03.770 align:start position:0% understand what was what is the failure um<01:01:02.280> well<01:01:02.700> that<01:01:02.940> is<01:01:03.059> that<01:01:03.299> is<01:01:03.420> a<01:01:03.660> different 01:01:03.770 --> 01:01:03.780 align:start position:0% um well that is that is a different 01:01:03.780 --> 01:01:06.890 align:start position:0% um well that is that is a different there<01:01:04.319> is<01:01:04.440> a<01:01:04.559> different<01:01:04.680> Beast<01:01:05.299> sometimes<01:01:06.299> you 01:01:06.890 --> 01:01:06.900 align:start position:0% there is a different Beast sometimes you 01:01:06.900 --> 01:01:10.670 align:start position:0% there is a different Beast sometimes you you<01:01:07.440> you<01:01:07.500> have<01:01:08.280> you<01:01:08.579> put<01:01:08.760> your<01:01:09.059> your 01:01:10.670 --> 01:01:10.680 align:start position:0% you you have you put your your 01:01:10.680 --> 01:01:12.890 align:start position:0% you you have you put your your um<01:01:10.740> your<01:01:11.460> invariant<01:01:12.119> and<01:01:12.299> your<01:01:12.480> invariant 01:01:12.890 --> 01:01:12.900 align:start position:0% um your invariant and your invariant 01:01:12.900 --> 01:01:16.309 align:start position:0% um your invariant and your invariant feels<01:01:13.319> and<01:01:14.220> then<01:01:15.180> you<01:01:15.359> start<01:01:15.599> the<01:01:15.780> journey<01:01:16.079> to 01:01:16.309 --> 01:01:16.319 align:start position:0% feels and then you start the journey to 01:01:16.319 --> 01:01:18.950 align:start position:0% feels and then you start the journey to understand<01:01:16.500> why<01:01:17.160> it<01:01:17.280> fits<01:01:17.640> so<01:01:18.299> that's<01:01:18.480> we<01:01:18.780> are 01:01:18.950 --> 01:01:18.960 align:start position:0% understand why it fits so that's we are 01:01:18.960 --> 01:01:21.829 align:start position:0% understand why it fits so that's we are not<01:01:19.079> going<01:01:19.200> to<01:01:19.319> talk<01:01:19.500> about<01:01:19.619> that<01:01:20.040> you<01:01:20.819> uh<01:01:21.540> some 01:01:21.829 --> 01:01:21.839 align:start position:0% not going to talk about that you uh some 01:01:21.839 --> 01:01:25.849 align:start position:0% not going to talk about that you uh some people<01:01:21.960> like<01:01:22.380> to<01:01:22.799> re-u<01:01:24.240> run<01:01:24.960> We<01:01:25.440> Run<01:01:25.619> The 01:01:25.849 --> 01:01:25.859 align:start position:0% people like to re-u run We Run The 01:01:25.859 --> 01:01:28.789 align:start position:0% people like to re-u run We Run The failure<01:01:26.280> into<01:01:26.579> a<01:01:26.819> unit<01:01:27.000> test<01:01:27.359> to<01:01:28.200> make<01:01:28.500> sure 01:01:28.789 --> 01:01:28.799 align:start position:0% failure into a unit test to make sure 01:01:28.799 --> 01:01:31.069 align:start position:0% failure into a unit test to make sure step<01:01:29.520> by<01:01:29.640> step<01:01:29.880> what<01:01:30.180> is<01:01:30.359> what<01:01:30.540> is<01:01:30.720> going<01:01:30.839> on 01:01:31.069 --> 01:01:31.079 align:start position:0% step by step what is what is going on 01:01:31.079 --> 01:01:33.170 align:start position:0% step by step what is what is going on but<01:01:31.680> yeah<01:01:31.859> that's<01:01:32.040> that's<01:01:32.400> a<01:01:32.760> completely 01:01:33.170 --> 01:01:33.180 align:start position:0% but yeah that's that's a completely 01:01:33.180 --> 01:01:35.630 align:start position:0% but yeah that's that's a completely different<01:01:33.420> uh<01:01:34.260> type<01:01:34.500> of<01:01:34.680> Beast<01:01:35.339> that<01:01:35.520> is 01:01:35.630 --> 01:01:35.640 align:start position:0% different uh type of Beast that is 01:01:35.640 --> 01:01:38.630 align:start position:0% different uh type of Beast that is related<01:01:35.940> with<01:01:36.240> what<01:01:36.780> happened<01:01:36.900> after<01:01:37.339> and<01:01:38.339> how 01:01:38.630 --> 01:01:38.640 align:start position:0% related with what happened after and how 01:01:38.640 --> 01:01:41.270 align:start position:0% related with what happened after and how we<01:01:38.940> can<01:01:39.119> fix<01:01:39.299> how<01:01:39.720> we<01:01:39.900> can<01:01:40.079> fixation 01:01:41.270 --> 01:01:41.280 align:start position:0% we can fix how we can fixation 01:01:41.280 --> 01:01:43.190 align:start position:0% we can fix how we can fixation all<01:01:41.819> right<01:01:41.940> so<01:01:42.240> a<01:01:42.420> little<01:01:42.480> bit<01:01:42.660> about<01:01:42.780> ekin 01:01:43.190 --> 01:01:43.200 align:start position:0% all right so a little bit about ekin 01:01:43.200 --> 01:01:44.870 align:start position:0% all right so a little bit about ekin apis<01:01:43.680> this<01:01:44.040> is 01:01:44.870 --> 01:01:44.880 align:start position:0% apis this is 01:01:44.880 --> 01:01:46.910 align:start position:0% apis this is um<01:01:44.940> a<01:01:45.240> topic<01:01:45.540> that 01:01:46.910 --> 01:01:46.920 align:start position:0% um a topic that 01:01:46.920 --> 01:01:47.510 align:start position:0% um a topic that um 01:01:47.510 --> 01:01:47.520 align:start position:0% um 01:01:47.520 --> 01:01:51.049 align:start position:0% um it's<01:01:48.240> uh<01:01:48.660> it's<01:01:49.200> it's<01:01:49.200> still<01:01:49.799> an<01:01:50.400> open<01:01:50.579> debate 01:01:51.049 --> 01:01:51.059 align:start position:0% it's uh it's it's still an open debate 01:01:51.059 --> 01:01:53.150 align:start position:0% it's uh it's it's still an open debate in<01:01:51.240> some<01:01:51.359> in<01:01:51.599> some<01:01:51.839> cases<01:01:52.140> so<01:01:52.559> what<01:01:52.799> are<01:01:53.040> the 01:01:53.150 --> 01:01:53.160 align:start position:0% in some in some cases so what are the 01:01:53.160 --> 01:01:56.450 align:start position:0% in some in some cases so what are the best<01:01:53.400> way<01:01:53.700> to<01:01:53.940> test<01:01:54.240> to<01:01:54.900> create<01:01:55.020> properties<01:01:55.619> so 01:01:56.450 --> 01:01:56.460 align:start position:0% best way to test to create properties so 01:01:56.460 --> 01:01:58.549 align:start position:0% best way to test to create properties so Echidna<01:01:57.119> supports<01:01:57.480> a<01:01:57.780> couple<01:01:57.900> different<01:01:58.140> ones 01:01:58.549 --> 01:01:58.559 align:start position:0% Echidna supports a couple different ones 01:01:58.559 --> 01:02:01.190 align:start position:0% Echidna supports a couple different ones it's<01:01:58.920> about<01:01:59.160> Boolean<01:01:59.640> properties<01:02:00.059> in<01:02:00.660> which<01:02:00.839> a 01:02:01.190 --> 01:02:01.200 align:start position:0% it's about Boolean properties in which a 01:02:01.200 --> 01:02:04.789 align:start position:0% it's about Boolean properties in which a function<01:02:01.760> uh<01:02:02.760> is<01:02:03.119> executed 01:02:04.789 --> 01:02:04.799 align:start position:0% function uh is executed 01:02:04.799 --> 01:02:08.030 align:start position:0% function uh is executed um<01:02:04.859> and<01:02:05.700> then<01:02:05.880> it<01:02:06.240> will<01:02:06.359> it<01:02:06.780> should<01:02:07.079> return<01:02:07.319> a 01:02:08.030 --> 01:02:08.040 align:start position:0% um and then it will it should return a 01:02:08.040 --> 01:02:09.950 align:start position:0% um and then it will it should return a Boolean<01:02:08.460> true<01:02:08.700> or<01:02:08.880> false<01:02:09.119> and<01:02:09.599> if<01:02:09.780> the 01:02:09.950 --> 01:02:09.960 align:start position:0% Boolean true or false and if the 01:02:09.960 --> 01:02:13.190 align:start position:0% Boolean true or false and if the function<01:02:10.260> reverts<01:02:10.920> for<01:02:11.520> any<01:02:11.760> reason<01:02:12.079> that<01:02:13.079> is 01:02:13.190 --> 01:02:13.200 align:start position:0% function reverts for any reason that is 01:02:13.200 --> 01:02:16.549 align:start position:0% function reverts for any reason that is the<01:02:13.500> same<01:02:13.680> as<01:02:14.220> returning<01:02:14.880> false<01:02:15.240> right<01:02:15.900> so<01:02:16.319> if 01:02:16.549 --> 01:02:16.559 align:start position:0% the same as returning false right so if 01:02:16.559 --> 01:02:19.490 align:start position:0% the same as returning false right so if we<01:02:16.740> go<01:02:16.920> back<01:02:17.099> a<01:02:17.460> little<01:02:17.579> bit<01:02:17.819> we<01:02:18.660> can<01:02:18.839> see<01:02:19.079> over 01:02:19.490 --> 01:02:19.500 align:start position:0% we go back a little bit we can see over 01:02:19.500 --> 01:02:22.910 align:start position:0% we go back a little bit we can see over there<01:02:19.760> error<01:02:20.760> and<01:02:21.119> recognize<01:02:21.599> op<01:02:22.020> code<01:02:22.260> that 01:02:22.910 --> 01:02:22.920 align:start position:0% there error and recognize op code that 01:02:22.920 --> 01:02:24.890 align:start position:0% there error and recognize op code that is<01:02:23.099> going<01:02:23.280> that<01:02:24.059> is<01:02:24.180> related<01:02:24.480> with<01:02:24.780> the 01:02:24.890 --> 01:02:24.900 align:start position:0% is going that is related with the 01:02:24.900 --> 01:02:28.250 align:start position:0% is going that is related with the assertion<01:02:25.319> failure<01:02:25.740> this<01:02:26.099> that<01:02:26.400> is<01:02:26.579> how 01:02:28.250 --> 01:02:28.260 align:start position:0% assertion failure this that is how 01:02:28.260 --> 01:02:31.190 align:start position:0% assertion failure this that is how um<01:02:28.380> on<01:02:29.040> version<01:02:29.280> of<01:02:29.579> solidity<01:02:30.000> used<01:02:30.299> to<01:02:30.480> uh 01:02:31.190 --> 01:02:31.200 align:start position:0% um on version of solidity used to uh 01:02:31.200 --> 01:02:33.109 align:start position:0% um on version of solidity used to uh have 01:02:33.109 --> 01:02:33.119 align:start position:0% have 01:02:33.119 --> 01:02:36.650 align:start position:0% have um<01:02:33.440> this<01:02:34.440> uh<01:02:34.740> assertion<01:02:35.400> failures<01:02:35.819> but<01:02:36.299> if<01:02:36.480> you 01:02:36.650 --> 01:02:36.660 align:start position:0% um this uh assertion failures but if you 01:02:36.660 --> 01:02:38.210 align:start position:0% um this uh assertion failures but if you use<01:02:36.780> Boolean<01:02:37.319> you<01:02:37.559> will<01:02:37.680> just<01:02:37.740> say<01:02:37.920> return 01:02:38.210 --> 01:02:38.220 align:start position:0% use Boolean you will just say return 01:02:38.220 --> 01:02:41.510 align:start position:0% use Boolean you will just say return false<01:02:38.760> right<01:02:39.299> so<01:02:39.599> you<01:02:39.780> know<01:02:39.900> exactly<01:02:40.380> how<01:02:40.740> how 01:02:41.510 --> 01:02:41.520 align:start position:0% false right so you know exactly how how 01:02:41.520 --> 01:02:44.390 align:start position:0% false right so you know exactly how how everybody<01:02:41.819> fail<01:02:42.780> uh<01:02:43.500> or<01:02:43.740> it<01:02:43.920> could<01:02:44.040> be<01:02:44.160> a 01:02:44.390 --> 01:02:44.400 align:start position:0% everybody fail uh or it could be a 01:02:44.400 --> 01:02:46.730 align:start position:0% everybody fail uh or it could be a revert<01:02:44.819> so<01:02:45.000> you<01:02:45.180> you<01:02:45.420> say<01:02:45.839> over<01:02:46.020> there<01:02:46.200> you<01:02:46.619> see 01:02:46.730 --> 01:02:46.740 align:start position:0% revert so you you say over there you see 01:02:46.740 --> 01:02:49.789 align:start position:0% revert so you you say over there you see over<01:02:46.859> there<01:02:47.099> it<01:02:47.400> revert<01:02:47.940> okay<01:02:48.660> so<01:02:49.200> either<01:02:49.440> you 01:02:49.789 --> 01:02:49.799 align:start position:0% over there it revert okay so either you 01:02:49.799 --> 01:02:52.010 align:start position:0% over there it revert okay so either you do<01:02:49.980> Boolean<01:02:50.520> properties<01:02:50.940> which<01:02:51.420> are<01:02:51.780> the 01:02:52.010 --> 01:02:52.020 align:start position:0% do Boolean properties which are the 01:02:52.020 --> 01:02:54.950 align:start position:0% do Boolean properties which are the classic<01:02:52.400> way<01:02:53.400> to<01:02:53.579> define<01:02:53.760> invariants<01:02:54.540> and 01:02:54.950 --> 01:02:54.960 align:start position:0% classic way to define invariants and 01:02:54.960 --> 01:02:58.190 align:start position:0% classic way to define invariants and these<01:02:55.200> come<01:02:55.380> from<01:02:55.680> uh<01:02:56.040> uh<01:02:56.760> some<01:02:56.940> some<01:02:57.000> real<01:02:57.540> old 01:02:58.190 --> 01:02:58.200 align:start position:0% these come from uh uh some some real old 01:02:58.200 --> 01:03:00.470 align:start position:0% these come from uh uh some some real old techniques<01:02:58.920> uh<01:02:59.339> in<01:02:59.520> particular<01:02:59.880> quick<01:03:00.240> check 01:03:00.470 --> 01:03:00.480 align:start position:0% techniques uh in particular quick check 01:03:00.480 --> 01:03:03.349 align:start position:0% techniques uh in particular quick check which<01:03:01.020> is<01:03:01.200> which<01:03:01.740> is<01:03:01.980> a<01:03:02.220> property<01:03:02.940> based 01:03:03.349 --> 01:03:03.359 align:start position:0% which is which is a property based 01:03:03.359 --> 01:03:05.450 align:start position:0% which is which is a property based testing<01:03:03.720> tool<01:03:04.140> for<01:03:04.380> Haskell<01:03:04.980> and<01:03:05.160> then<01:03:05.280> a 01:03:05.450 --> 01:03:05.460 align:start position:0% testing tool for Haskell and then a 01:03:05.460 --> 01:03:07.970 align:start position:0% testing tool for Haskell and then a couple<01:03:05.520> of<01:03:05.640> other<01:03:06.000> languages<01:03:06.559> uh<01:03:07.559> which<01:03:07.799> was 01:03:07.970 --> 01:03:07.980 align:start position:0% couple of other languages uh which was 01:03:07.980 --> 01:03:11.270 align:start position:0% couple of other languages uh which was an<01:03:08.220> inspiration<01:03:08.640> for<01:03:09.059> for<01:03:09.660> for<01:03:09.780> this<01:03:10.440> then<01:03:11.040> you 01:03:11.270 --> 01:03:11.280 align:start position:0% an inspiration for for for this then you 01:03:11.280 --> 01:03:13.970 align:start position:0% an inspiration for for for this then you have<01:03:11.400> assertion<01:03:11.880> failure<01:03:12.299> so<01:03:13.020> every<01:03:13.440> time<01:03:13.680> you 01:03:13.970 --> 01:03:13.980 align:start position:0% have assertion failure so every time you 01:03:13.980 --> 01:03:17.870 align:start position:0% have assertion failure so every time you see<01:03:14.220> uh<01:03:15.000> every<01:03:15.540> time<01:03:15.780> uh<01:03:16.440> the<01:03:17.160> the<01:03:17.400> assertion 01:03:17.870 --> 01:03:17.880 align:start position:0% see uh every time uh the the assertion 01:03:17.880 --> 01:03:21.109 align:start position:0% see uh every time uh the the assertion is<01:03:18.059> called<01:03:18.240> with<01:03:18.420> false<01:03:18.900> that<01:03:19.799> is<01:03:19.980> uh<01:03:20.880> that 01:03:21.109 --> 01:03:21.119 align:start position:0% is called with false that is uh that 01:03:21.119 --> 01:03:23.870 align:start position:0% is called with false that is uh that will<01:03:21.240> fail<01:03:21.540> however<01:03:22.440> if<01:03:22.980> in<01:03:23.280> the<01:03:23.400> context<01:03:23.700> of 01:03:23.870 --> 01:03:23.880 align:start position:0% will fail however if in the context of 01:03:23.880 --> 01:03:26.809 align:start position:0% will fail however if in the context of your<01:03:24.119> function<01:03:24.540> you<01:03:25.020> see<01:03:25.200> a<01:03:25.380> revert<01:03:25.799> that<01:03:26.579> will 01:03:26.809 --> 01:03:26.819 align:start position:0% your function you see a revert that will 01:03:26.819 --> 01:03:28.789 align:start position:0% your function you see a revert that will not<01:03:27.119> make<01:03:27.660> the<01:03:27.900> function 01:03:28.789 --> 01:03:28.799 align:start position:0% not make the function 01:03:28.799 --> 01:03:31.450 align:start position:0% not make the function um the<01:03:29.040> property<01:03:29.339> fail<01:03:29.640> here<01:03:30.359> we<01:03:30.839> can<01:03:31.020> see 01:03:31.450 --> 01:03:31.460 align:start position:0% um the property fail here we can see 01:03:31.460 --> 01:03:36.770 align:start position:0% um the property fail here we can see that<01:03:32.460> if<01:03:33.299> valid<01:03:33.960> by<01:03:34.140> reverts<01:03:34.859> then<01:03:35.640> the<01:03:36.240> this 01:03:36.770 --> 01:03:36.780 align:start position:0% that if valid by reverts then the this 01:03:36.780 --> 01:03:39.770 align:start position:0% that if valid by reverts then the this Kindle<01:03:37.680> will<01:03:37.859> not<01:03:37.920> report<01:03:38.160> that<01:03:38.520> because<01:03:39.359> we 01:03:39.770 --> 01:03:39.780 align:start position:0% Kindle will not report that because we 01:03:39.780 --> 01:03:41.690 align:start position:0% Kindle will not report that because we are<01:03:39.960> using<01:03:40.260> assertion<01:03:40.740> mode 01:03:41.690 --> 01:03:41.700 align:start position:0% are using assertion mode 01:03:41.700 --> 01:03:45.109 align:start position:0% are using assertion mode fine<01:03:42.420> so<01:03:43.380> you<01:03:43.559> you<01:03:43.799> should<01:03:44.099> be<01:03:44.400> careful<01:03:44.640> if<01:03:44.940> you 01:03:45.109 --> 01:03:45.119 align:start position:0% fine so you you should be careful if you 01:03:45.119 --> 01:03:48.010 align:start position:0% fine so you you should be careful if you are<01:03:45.240> using<01:03:45.780> if<01:03:46.319> you<01:03:46.440> if<01:03:46.799> you<01:03:46.980> cannot<01:03:47.280> rewards 01:03:48.010 --> 01:03:48.020 align:start position:0% are using if you if you cannot rewards 01:03:48.020 --> 01:03:52.430 align:start position:0% are using if you if you cannot rewards uh<01:03:49.020> you<01:03:49.319> should<01:03:49.500> have<01:03:49.740> to<01:03:50.220> uh<01:03:50.940> either<01:03:51.180> use<01:03:51.599> the 01:03:52.430 --> 01:03:52.440 align:start position:0% uh you should have to uh either use the 01:03:52.440 --> 01:03:54.170 align:start position:0% uh you should have to uh either use the um<01:03:52.500> the<01:03:53.099> type<01:03:53.220> of 01:03:54.170 --> 01:03:54.180 align:start position:0% um the type of 01:03:54.180 --> 01:03:57.470 align:start position:0% um the type of um the<01:03:55.140> Boolean<01:03:55.559> type<01:03:55.740> or<01:03:56.640> what<01:03:57.059> you<01:03:57.180> can<01:03:57.299> do 01:03:57.470 --> 01:03:57.480 align:start position:0% um the Boolean type or what you can do 01:03:57.480 --> 01:03:59.630 align:start position:0% um the Boolean type or what you can do is<01:03:57.660> if<01:03:57.900> you<01:03:58.079> care<01:03:58.200> about<01:03:58.380> reverts<01:03:58.980> invalid<01:03:59.400> boy 01:03:59.630 --> 01:03:59.640 align:start position:0% is if you care about reverts invalid boy 01:03:59.640 --> 01:04:02.089 align:start position:0% is if you care about reverts invalid boy and<01:04:00.180> if<01:04:00.359> it's<01:04:00.540> an<01:04:00.660> external<01:04:01.079> function<01:04:01.440> you<01:04:02.040> can 01:04:02.089 --> 01:04:02.099 align:start position:0% and if it's an external function you can 01:04:02.099 --> 01:04:04.130 align:start position:0% and if it's an external function you can do<01:04:02.220> a<01:04:02.339> try<01:04:02.460> and<01:04:02.700> catch<01:04:03.000> and<01:04:03.299> you<01:04:03.540> can<01:04:03.660> check 01:04:04.130 --> 01:04:04.140 align:start position:0% do a try and catch and you can check 01:04:04.140 --> 01:04:06.250 align:start position:0% do a try and catch and you can check which<01:04:04.440> type<01:04:04.680> of<01:04:04.799> reverse<01:04:05.280> and<01:04:05.700> you<01:04:05.880> can<01:04:06.000> even 01:04:06.250 --> 01:04:06.260 align:start position:0% which type of reverse and you can even 01:04:06.260 --> 01:04:09.230 align:start position:0% which type of reverse and you can even fail<01:04:07.260> in<01:04:07.500> some<01:04:07.920> type<01:04:08.099> of<01:04:08.220> reverse<01:04:08.700> and<01:04:08.940> not<01:04:09.059> in 01:04:09.230 --> 01:04:09.240 align:start position:0% fail in some type of reverse and not in 01:04:09.240 --> 01:04:11.510 align:start position:0% fail in some type of reverse and not in other<01:04:09.420> because<01:04:09.780> you<01:04:10.260> want<01:04:10.500> the<01:04:10.680> user<01:04:10.980> to<01:04:11.160> get<01:04:11.339> a 01:04:11.510 --> 01:04:11.520 align:start position:0% other because you want the user to get a 01:04:11.520 --> 01:04:13.789 align:start position:0% other because you want the user to get a good<01:04:11.640> message<01:04:11.880> of<01:04:12.240> of<01:04:12.480> alert<01:04:12.900> and<01:04:13.200> perhaps 01:04:13.789 --> 01:04:13.799 align:start position:0% good message of of alert and perhaps 01:04:13.799 --> 01:04:15.829 align:start position:0% good message of of alert and perhaps other<01:04:14.099> type<01:04:14.400> of<01:04:14.460> reverse<01:04:14.880> you<01:04:15.119> don't 01:04:15.829 --> 01:04:15.839 align:start position:0% other type of reverse you don't 01:04:15.839 --> 01:04:18.349 align:start position:0% other type of reverse you don't you<01:04:16.680> you<01:04:16.920> want<01:04:17.160> to<01:04:17.280> know<01:04:17.400> so 01:04:18.349 --> 01:04:18.359 align:start position:0% you you want to know so 01:04:18.359 --> 01:04:20.809 align:start position:0% you you want to know so and<01:04:18.900> finally<01:04:19.260> we<01:04:19.559> have<01:04:19.740> the<01:04:19.920> DAP<01:04:20.220> and<01:04:20.400> Foundry 01:04:20.809 --> 01:04:20.819 align:start position:0% and finally we have the DAP and Foundry 01:04:20.819 --> 01:04:23.569 align:start position:0% and finally we have the DAP and Foundry API<01:04:21.500> in<01:04:22.500> which 01:04:23.569 --> 01:04:23.579 align:start position:0% API in which 01:04:23.579 --> 01:04:26.930 align:start position:0% API in which um<01:04:24.000> you<01:04:24.660> will<01:04:24.900> uh<01:04:25.559> you<01:04:25.859> will<01:04:26.040> have 01:04:26.930 --> 01:04:26.940 align:start position:0% um you will uh you will have 01:04:26.940 --> 01:04:30.710 align:start position:0% um you will uh you will have um<01:04:27.000> a<01:04:27.480> function<01:04:27.720> that<01:04:27.960> if<01:04:28.079> it<01:04:28.319> reverts<01:04:29.280> uh<01:04:30.240> it's 01:04:30.710 --> 01:04:30.720 align:start position:0% um a function that if it reverts uh it's 01:04:30.720 --> 01:04:33.230 align:start position:0% um a function that if it reverts uh it's going<01:04:30.960> to<01:04:31.500> it's<01:04:32.339> going<01:04:32.579> to<01:04:32.700> fail<01:04:32.880> and 01:04:33.230 --> 01:04:33.240 align:start position:0% going to it's going to fail and 01:04:33.240 --> 01:04:35.030 align:start position:0% going to it's going to fail and otherwise<01:04:33.599> it's<01:04:34.200> not<01:04:34.380> and<01:04:34.619> I<01:04:34.799> hope<01:04:34.920> The 01:04:35.030 --> 01:04:35.040 align:start position:0% otherwise it's not and I hope The 01:04:35.040 --> 01:04:36.250 align:start position:0% otherwise it's not and I hope The Foundry<01:04:35.520> team 01:04:36.250 --> 01:04:36.260 align:start position:0% Foundry team 01:04:36.260 --> 01:04:39.890 align:start position:0% Foundry team agree<01:04:37.260> with<01:04:37.380> us<01:04:37.619> and<01:04:37.859> it's<01:04:38.099> uh<01:04:38.940> is<01:04:39.420> correctly 01:04:39.890 --> 01:04:39.900 align:start position:0% agree with us and it's uh is correctly 01:04:39.900 --> 01:04:41.329 align:start position:0% agree with us and it's uh is correctly implemented 01:04:41.329 --> 01:04:41.339 align:start position:0% implemented 01:04:41.339 --> 01:04:44.210 align:start position:0% implemented um<01:04:41.460> all<01:04:41.640> right<01:04:41.819> so<01:04:42.180> there<01:04:42.480> is<01:04:42.660> testing<01:04:43.140> modes 01:04:44.210 --> 01:04:44.220 align:start position:0% um all right so there is testing modes 01:04:44.220 --> 01:04:47.329 align:start position:0% um all right so there is testing modes um<01:04:44.700> in<01:04:45.540> the<01:04:45.720> in<01:04:46.559> the 01:04:47.329 --> 01:04:47.339 align:start position:0% um in the in the 01:04:47.339 --> 01:04:50.329 align:start position:0% um in the in the um<01:04:47.400> in<01:04:47.640> a<01:04:47.880> repository<01:04:48.420> so<01:04:49.319> we<01:04:49.559> can 01:04:50.329 --> 01:04:50.339 align:start position:0% um in a repository so we can 01:04:50.339 --> 01:04:52.609 align:start position:0% um in a repository so we can um<01:04:50.400> you<01:04:50.940> can<01:04:51.059> go<01:04:51.240> there<01:04:51.420> and<01:04:51.599> it's<01:04:51.720> explained<01:04:52.500> a 01:04:52.609 --> 01:04:52.619 align:start position:0% um you can go there and it's explained a 01:04:52.619 --> 01:04:54.950 align:start position:0% um you can go there and it's explained a little<01:04:52.680> bit<01:04:52.799> more<01:04:53.099> this<01:04:53.940> is<01:04:54.240> very<01:04:54.540> high<01:04:54.780> level 01:04:54.950 --> 01:04:54.960 align:start position:0% little bit more this is very high level 01:04:54.960 --> 01:04:57.770 align:start position:0% little bit more this is very high level overview<01:04:55.640> so<01:04:56.640> yeah 01:04:57.770 --> 01:04:57.780 align:start position:0% overview so yeah 01:04:57.780 --> 01:05:01.250 align:start position:0% overview so yeah yeah<01:04:58.380> yeah<01:04:58.680> so<01:04:58.859> so<01:04:58.980> so<01:04:59.180> yeah<01:05:00.180> again<01:05:00.960> that's 01:05:01.250 --> 01:05:01.260 align:start position:0% yeah yeah so so so yeah again that's 01:05:01.260 --> 01:05:04.069 align:start position:0% yeah yeah so so so yeah again that's something<01:05:01.440> returnable<01:05:02.040> Boolean<01:05:02.880> uh<01:05:03.839> it's 01:05:04.069 --> 01:05:04.079 align:start position:0% something returnable Boolean uh it's 01:05:04.079 --> 01:05:06.890 align:start position:0% something returnable Boolean uh it's easy<01:05:04.260> to<01:05:04.680> Define<01:05:04.940> uh<01:05:05.940> no<01:05:06.119> side<01:05:06.359> effects<01:05:06.660> that's 01:05:06.890 --> 01:05:06.900 align:start position:0% easy to Define uh no side effects that's 01:05:06.900 --> 01:05:10.309 align:start position:0% easy to Define uh no side effects that's that<01:05:07.200> that<01:05:07.500> is<01:05:08.160> so<01:05:08.400> interesting<01:05:09.059> when<01:05:09.780> you<01:05:09.960> use 01:05:10.309 --> 01:05:10.319 align:start position:0% that that is so interesting when you use 01:05:10.319 --> 01:05:12.349 align:start position:0% that that is so interesting when you use Boolean<01:05:10.740> properties<01:05:11.099> all<01:05:11.700> the<01:05:11.819> side<01:05:12.000> effects 01:05:12.349 --> 01:05:12.359 align:start position:0% Boolean properties all the side effects 01:05:12.359 --> 01:05:15.170 align:start position:0% Boolean properties all the side effects will<01:05:12.599> be<01:05:12.720> reverted<01:05:13.319> uh<01:05:14.280> before<01:05:14.520> the<01:05:14.819> execution 01:05:15.170 --> 01:05:15.180 align:start position:0% will be reverted uh before the execution 01:05:15.180 --> 01:05:18.230 align:start position:0% will be reverted uh before the execution of<01:05:15.480> the<01:05:15.720> actual<01:05:16.020> invariant<01:05:16.799> right<01:05:17.640> but<01:05:18.119> if 01:05:18.230 --> 01:05:18.240 align:start position:0% of the actual invariant right but if 01:05:18.240 --> 01:05:21.770 align:start position:0% of the actual invariant right but if you're<01:05:18.420> using<01:05:18.780> assert<01:05:19.640> the<01:05:20.640> side<01:05:21.119> effects<01:05:21.480> so 01:05:21.770 --> 01:05:21.780 align:start position:0% you're using assert the side effects so 01:05:21.780 --> 01:05:23.210 align:start position:0% you're using assert the side effects so everything<01:05:22.020> you<01:05:22.260> change<01:05:22.500> in<01:05:22.680> the<01:05:22.799> blockchain 01:05:23.210 --> 01:05:23.220 align:start position:0% everything you change in the blockchain 01:05:23.220 --> 01:05:26.750 align:start position:0% everything you change in the blockchain will<01:05:24.000> will<01:05:24.599> remain<01:05:25.020> so<01:05:25.619> this<01:05:26.040> can<01:05:26.400> be<01:05:26.579> really 01:05:26.750 --> 01:05:26.760 align:start position:0% will will remain so this can be really 01:05:26.760 --> 01:05:28.910 align:start position:0% will will remain so this can be really useful<01:05:27.119> for<01:05:27.780> testing<01:05:28.140> some<01:05:28.319> some<01:05:28.500> complex 01:05:28.910 --> 01:05:28.920 align:start position:0% useful for testing some some complex 01:05:28.920 --> 01:05:32.630 align:start position:0% useful for testing some some complex code<01:05:29.160> but<01:05:29.640> yeah<01:05:29.819> we're<01:05:30.000> not<01:05:30.240> going<01:05:30.359> to<01:05:30.960> well 01:05:32.630 --> 01:05:32.640 align:start position:0% code but yeah we're not going to well 01:05:32.640 --> 01:05:37.190 align:start position:0% code but yeah we're not going to well um<01:05:32.700> yeah<01:05:32.940> assertion<01:05:33.720> is<01:05:34.380> can<01:05:34.680> be<01:05:34.799> simple<01:05:35.040> to<01:05:35.520> to 01:05:37.190 --> 01:05:37.200 align:start position:0% um yeah assertion is can be simple to to 01:05:37.200 --> 01:05:39.650 align:start position:0% um yeah assertion is can be simple to to um<01:05:37.260> Define 01:05:39.650 --> 01:05:39.660 align:start position:0% um Define 01:05:39.660 --> 01:05:42.289 align:start position:0% um Define um<01:05:39.720> and<01:05:40.020> it's<01:05:40.200> it's<01:05:40.559> it<01:05:41.040> will<01:05:41.280> also 01:05:42.289 --> 01:05:42.299 align:start position:0% um and it's it's it will also 01:05:42.299 --> 01:05:44.809 align:start position:0% um and it's it's it will also um<01:05:42.420> it<01:05:42.780> will<01:05:42.960> also<01:05:43.260> be<01:05:43.680> easy<01:05:43.920> to<01:05:44.220> see<01:05:44.400> on<01:05:44.700> the 01:05:44.809 --> 01:05:44.819 align:start position:0% um it will also be easy to see on the 01:05:44.819 --> 01:05:46.609 align:start position:0% um it will also be easy to see on the code<01:05:44.940> coverage<01:05:45.359> if<01:05:45.720> it's<01:05:45.900> not<01:05:46.079> if<01:05:46.380> it's<01:05:46.559> not 01:05:46.609 --> 01:05:46.619 align:start position:0% code coverage if it's not if it's not 01:05:46.619 --> 01:05:50.630 align:start position:0% code coverage if it's not if it's not covered<01:05:47.040> or<01:05:47.460> or<01:05:48.240> not<01:05:48.420> however<01:05:48.960> some<01:05:49.680> code 01:05:50.630 --> 01:05:50.640 align:start position:0% covered or or not however some code 01:05:50.640 --> 01:05:52.789 align:start position:0% covered or or not however some code especially<01:05:51.299> some<01:05:51.599> old<01:05:51.839> piece<01:05:52.200> of<01:05:52.260> solitary 01:05:52.789 --> 01:05:52.799 align:start position:0% especially some old piece of solitary 01:05:52.799 --> 01:05:55.370 align:start position:0% especially some old piece of solitary code<01:05:52.920> it's<01:05:53.400> going<01:05:53.579> to<01:05:53.760> have<01:05:54.119> assertion<01:05:54.839> as 01:05:55.370 --> 01:05:55.380 align:start position:0% code it's going to have assertion as 01:05:55.380 --> 01:05:57.829 align:start position:0% code it's going to have assertion as required<01:05:55.980> and<01:05:56.460> that<01:05:56.579> is<01:05:56.819> a<01:05:57.059> really<01:05:57.420> bad<01:05:57.660> thing 01:05:57.829 --> 01:05:57.839 align:start position:0% required and that is a really bad thing 01:05:57.839 --> 01:05:59.990 align:start position:0% required and that is a really bad thing you<01:05:58.079> should<01:05:58.200> not<01:05:58.380> be<01:05:58.559> doing<01:05:58.740> it<01:05:59.040> use<01:05:59.640> require 01:05:59.990 --> 01:06:00.000 align:start position:0% you should not be doing it use require 01:06:00.000 --> 01:06:03.530 align:start position:0% you should not be doing it use require if<01:06:00.480> you<01:06:00.599> want<01:06:00.839> to<01:06:01.020> if<01:06:01.619> you<01:06:01.799> want<01:06:01.980> to<01:06:02.099> actually 01:06:03.530 --> 01:06:03.540 align:start position:0% if you want to if you want to actually 01:06:03.540 --> 01:06:05.930 align:start position:0% if you want to if you want to actually um<01:06:03.599> have<01:06:04.260> a<01:06:04.440> precondition<01:06:04.980> in<01:06:05.400> your<01:06:05.520> call<01:06:05.700> and 01:06:05.930 --> 01:06:05.940 align:start position:0% um have a precondition in your call and 01:06:05.940 --> 01:06:09.730 align:start position:0% um have a precondition in your call and use<01:06:06.119> assertion<01:06:06.660> for<01:06:06.960> for<01:06:07.260> testing 01:06:09.730 --> 01:06:09.740 align:start position:0% use assertion for for testing 01:06:09.740 --> 01:06:11.329 align:start position:0% use assertion for for testing okay 01:06:11.329 --> 01:06:11.339 align:start position:0% okay 01:06:11.339 --> 01:06:13.130 align:start position:0% okay um<01:06:11.400> yeah<01:06:11.700> and<01:06:11.880> finally<01:06:12.299> we<01:06:12.480> have<01:06:12.660> the<01:06:12.900> The 01:06:13.130 --> 01:06:13.140 align:start position:0% um yeah and finally we have the The 01:06:13.140 --> 01:06:16.970 align:start position:0% um yeah and finally we have the The Foundry<01:06:13.740> and<01:06:14.460> up<01:06:14.819> uh<01:06:15.299> compatibility<01:06:15.900> the<01:06:16.859> only 01:06:16.970 --> 01:06:16.980 align:start position:0% Foundry and up uh compatibility the only 01:06:16.980 --> 01:06:19.549 align:start position:0% Foundry and up uh compatibility the only thing<01:06:17.280> well<01:06:17.700> uh<01:06:18.540> the<01:06:18.900> thing<01:06:19.020> that<01:06:19.200> we<01:06:19.440> don't 01:06:19.549 --> 01:06:19.559 align:start position:0% thing well uh the thing that we don't 01:06:19.559 --> 01:06:21.410 align:start position:0% thing well uh the thing that we don't support<01:06:19.859> is<01:06:20.220> pranks<01:06:20.700> so<01:06:20.819> we<01:06:21.000> don't<01:06:21.059> like<01:06:21.240> to 01:06:21.410 --> 01:06:21.420 align:start position:0% support is pranks so we don't like to 01:06:21.420 --> 01:06:24.410 align:start position:0% support is pranks so we don't like to prank<01:06:21.720> people<01:06:21.980> so<01:06:22.980> we<01:06:23.880> don't<01:06:23.940> we<01:06:24.240> don't 01:06:24.410 --> 01:06:24.420 align:start position:0% prank people so we don't we don't 01:06:24.420 --> 01:06:27.049 align:start position:0% prank people so we don't we don't support<01:06:24.539> pranks<01:06:25.260> however<01:06:26.039> we<01:06:26.280> support<01:06:26.579> some 01:06:27.049 --> 01:06:27.059 align:start position:0% support pranks however we support some 01:06:27.059 --> 01:06:29.630 align:start position:0% support pranks however we support some of<01:06:27.240> the<01:06:27.539> some<01:06:28.260> of<01:06:28.440> the 01:06:29.630 --> 01:06:29.640 align:start position:0% of the some of the 01:06:29.640 --> 01:06:32.870 align:start position:0% of the some of the um<01:06:29.780> uh<01:06:30.780> havm<01:06:31.500> yeah<01:06:31.740> the<01:06:31.980> havm<01:06:32.520> the<01:06:32.760> original 01:06:32.870 --> 01:06:32.880 align:start position:0% um uh havm yeah the havm the original 01:06:32.880 --> 01:06:35.510 align:start position:0% um uh havm yeah the havm the original ones<01:06:33.539> uh<01:06:34.319> cheat<01:06:34.500> codes 01:06:35.510 --> 01:06:35.520 align:start position:0% ones uh cheat codes 01:06:35.520 --> 01:06:39.650 align:start position:0% ones uh cheat codes you<01:06:36.119> should<01:06:36.240> be<01:06:36.359> careful<01:06:36.599> using<01:06:37.140> it<01:06:37.280> uh<01:06:38.280> we<01:06:39.180> uh 01:06:39.650 --> 01:06:39.660 align:start position:0% you should be careful using it uh we uh 01:06:39.660 --> 01:06:42.770 align:start position:0% you should be careful using it uh we uh we<01:06:40.079> know<01:06:40.200> that<01:06:40.440> there<01:06:40.619> are<01:06:40.799> some<01:06:41.099> uh<01:06:41.880> catch 01:06:42.770 --> 01:06:42.780 align:start position:0% we know that there are some uh catch 01:06:42.780 --> 01:06:46.190 align:start position:0% we know that there are some uh catch with<01:06:42.960> that<01:06:43.400> especially<01:06:44.400> related<01:06:45.000> uh<01:06:45.839> with 01:06:46.190 --> 01:06:46.200 align:start position:0% with that especially related uh with 01:06:46.200 --> 01:06:49.370 align:start position:0% with that especially related uh with what<01:06:46.740> the<01:06:46.920> solid<01:06:47.280> compiler<01:06:47.760> expects<01:06:48.420> and<01:06:49.140> what 01:06:49.370 --> 01:06:49.380 align:start position:0% what the solid compiler expects and what 01:06:49.380 --> 01:06:51.970 align:start position:0% what the solid compiler expects and what you're<01:06:49.559> doing<01:06:49.799> in<01:06:50.160> your<01:06:50.339> in<01:06:50.819> your<01:06:51.059> transaction 01:06:51.970 --> 01:06:51.980 align:start position:0% you're doing in your in your transaction 01:06:51.980 --> 01:06:55.069 align:start position:0% you're doing in your in your transaction so<01:06:52.980> please<01:06:53.400> be<01:06:53.640> careful<01:06:54.000> because<01:06:54.359> you<01:06:54.960> could 01:06:55.069 --> 01:06:55.079 align:start position:0% so please be careful because you could 01:06:55.079 --> 01:06:57.170 align:start position:0% so please be careful because you could have<01:06:55.380> some<01:06:55.740> uh 01:06:57.170 --> 01:06:57.180 align:start position:0% have some uh 01:06:57.180 --> 01:07:01.609 align:start position:0% have some uh um<01:06:57.299> some<01:06:57.780> some<01:06:57.780> issues<01:06:59.160> so<01:06:59.819> we<01:07:00.240> in<01:07:00.539> we<01:07:01.380> rarely 01:07:01.609 --> 01:07:01.619 align:start position:0% um some some issues so we in we rarely 01:07:01.619 --> 01:07:05.029 align:start position:0% um some some issues so we in we rarely use<01:07:01.920> cheat<01:07:02.220> codes<01:07:02.460> uh<01:07:03.240> we<01:07:03.420> try<01:07:03.599> to<01:07:03.780> keep<01:07:04.140> all 01:07:05.029 --> 01:07:05.039 align:start position:0% use cheat codes uh we try to keep all 01:07:05.039 --> 01:07:07.490 align:start position:0% use cheat codes uh we try to keep all our<01:07:05.579> code<01:07:05.940> as<01:07:06.359> close<01:07:06.599> at<01:07:06.839> the<01:07:07.020> solidity 01:07:07.490 --> 01:07:07.500 align:start position:0% our code as close at the solidity 01:07:07.500 --> 01:07:09.650 align:start position:0% our code as close at the solidity possible<01:07:07.980> so<01:07:08.640> you<01:07:08.760> can<01:07:08.880> easily<01:07:09.119> Port<01:07:09.359> it<01:07:09.539> to 01:07:09.650 --> 01:07:09.660 align:start position:0% possible so you can easily Port it to 01:07:09.660 --> 01:07:11.690 align:start position:0% possible so you can easily Port it to another<01:07:09.780> tool<01:07:10.319> there's<01:07:10.740> there's<01:07:11.280> little 01:07:11.690 --> 01:07:11.700 align:start position:0% another tool there's there's little 01:07:11.700 --> 01:07:14.270 align:start position:0% another tool there's there's little Akinator<01:07:12.420> specific<01:07:12.720> uh<01:07:13.619> but<01:07:13.799> yeah<01:07:13.920> we<01:07:14.160> are 01:07:14.270 --> 01:07:14.280 align:start position:0% Akinator specific uh but yeah we are 01:07:14.280 --> 01:07:16.609 align:start position:0% Akinator specific uh but yeah we are also<01:07:14.520> open<01:07:14.640> to<01:07:14.880> discussion<01:07:15.359> if<01:07:15.660> if<01:07:16.319> the 01:07:16.609 --> 01:07:16.619 align:start position:0% also open to discussion if if the 01:07:16.619 --> 01:07:18.470 align:start position:0% also open to discussion if if the community<01:07:16.799> agrees<01:07:17.400> that<01:07:17.640> we<01:07:17.819> need<01:07:18.000> a<01:07:18.180> specific 01:07:18.470 --> 01:07:18.480 align:start position:0% community agrees that we need a specific 01:07:18.480 --> 01:07:20.089 align:start position:0% community agrees that we need a specific cheat<01:07:18.720> code<01:07:18.960> or<01:07:19.200> we<01:07:19.319> need<01:07:19.440> to<01:07:19.559> avoid<01:07:19.859> some 01:07:20.089 --> 01:07:20.099 align:start position:0% cheat code or we need to avoid some 01:07:20.099 --> 01:07:22.190 align:start position:0% cheat code or we need to avoid some specific<01:07:20.460> chicken<01:07:20.700> then<01:07:21.359> we<01:07:21.599> are<01:07:21.780> open<01:07:21.960> to 01:07:22.190 --> 01:07:22.200 align:start position:0% specific chicken then we are open to 01:07:22.200 --> 01:07:23.390 align:start position:0% specific chicken then we are open to discuss<01:07:22.619> it 01:07:23.390 --> 01:07:23.400 align:start position:0% discuss it 01:07:23.400 --> 01:07:25.730 align:start position:0% discuss it all<01:07:23.940> right 01:07:25.730 --> 01:07:25.740 align:start position:0% all right 01:07:25.740 --> 01:07:29.630 align:start position:0% all right um<01:07:25.880> so<01:07:26.880> exercise<01:07:27.180> four<01:07:27.720> we're<01:07:28.140> going<01:07:28.440> to<01:07:28.920> deal 01:07:29.630 --> 01:07:29.640 align:start position:0% um so exercise four we're going to deal 01:07:29.640 --> 01:07:31.849 align:start position:0% um so exercise four we're going to deal with<01:07:29.880> uh 01:07:31.849 --> 01:07:31.859 align:start position:0% with uh 01:07:31.859 --> 01:07:34.250 align:start position:0% with uh um<01:07:31.980> one<01:07:32.760> of<01:07:32.940> the 01:07:34.250 --> 01:07:34.260 align:start position:0% um one of the 01:07:34.260 --> 01:07:37.670 align:start position:0% um one of the um<01:07:34.380> one<01:07:34.859> of<01:07:34.980> the<01:07:35.480> exercise<01:07:36.480> for<01:07:37.020> dumb 01:07:37.670 --> 01:07:37.680 align:start position:0% um one of the exercise for dumb 01:07:37.680 --> 01:07:40.789 align:start position:0% um one of the exercise for dumb vulnerable<01:07:38.180> defy<01:07:39.180> so<01:07:39.599> how<01:07:39.780> many<01:07:39.960> of<01:07:40.140> you<01:07:40.380> know 01:07:40.789 --> 01:07:40.799 align:start position:0% vulnerable defy so how many of you know 01:07:40.799 --> 01:07:42.710 align:start position:0% vulnerable defy so how many of you know this<01:07:41.339> uh 01:07:42.710 --> 01:07:42.720 align:start position:0% this uh 01:07:42.720 --> 01:07:45.589 align:start position:0% this uh um<01:07:42.839> amazing<01:07:43.500> uh<01:07:44.339> CTF 01:07:45.589 --> 01:07:45.599 align:start position:0% um amazing uh CTF 01:07:45.599 --> 01:07:46.970 align:start position:0% um amazing uh CTF um 01:07:46.970 --> 01:07:46.980 align:start position:0% um 01:07:46.980 --> 01:07:50.029 align:start position:0% um ah<01:07:47.760> yeah<01:07:47.880> sorry<01:07:48.359> you<01:07:48.900> you<01:07:49.140> yeah<01:07:49.740> we're<01:07:49.920> going 01:07:50.029 --> 01:07:50.039 align:start position:0% ah yeah sorry you you yeah we're going 01:07:50.039 --> 01:07:51.589 align:start position:0% ah yeah sorry you you yeah we're going to<01:07:50.099> keep<01:07:50.220> it<01:07:50.400> up<01:07:50.520> yeah<01:07:50.760> yeah<01:07:50.819> we<01:07:51.119> can<01:07:51.240> yeah<01:07:51.420> we 01:07:51.589 --> 01:07:51.599 align:start position:0% to keep it up yeah yeah we can yeah we 01:07:51.599 --> 01:07:53.210 align:start position:0% to keep it up yeah yeah we can yeah we can<01:07:51.780> skip<01:07:51.900> it<01:07:52.140> this<01:07:52.260> is<01:07:52.440> term<01:07:52.680> so<01:07:52.920> this 01:07:53.210 --> 01:07:53.220 align:start position:0% can skip it this is term so this 01:07:53.220 --> 01:07:55.309 align:start position:0% can skip it this is term so this exercise<01:07:53.400> was<01:07:53.880> exactly<01:07:54.299> the<01:07:54.599> same<01:07:54.960> as<01:07:55.140> the 01:07:55.309 --> 01:07:55.319 align:start position:0% exercise was exactly the same as the 01:07:55.319 --> 01:07:57.289 align:start position:0% exercise was exactly the same as the first<01:07:55.440> one<01:07:55.619> but<01:07:55.799> instead<01:07:56.099> of<01:07:56.220> using<01:07:56.579> function 01:07:57.289 --> 01:07:57.299 align:start position:0% first one but instead of using function 01:07:57.299 --> 01:08:00.349 align:start position:0% first one but instead of using function uh<01:07:58.220> we<01:07:59.220> were<01:07:59.339> using<01:07:59.579> assertion<01:08:00.000> so<01:08:00.299> it's 01:08:00.349 --> 01:08:00.359 align:start position:0% uh we were using assertion so it's 01:08:00.359 --> 01:08:02.270 align:start position:0% uh we were using assertion so it's exactly<01:08:00.660> the<01:08:00.900> same<01:08:01.079> invariant<01:08:01.559> exactly<01:08:02.039> the 01:08:02.270 --> 01:08:02.280 align:start position:0% exactly the same invariant exactly the 01:08:02.280 --> 01:08:04.730 align:start position:0% exactly the same invariant exactly the same<01:08:02.460> setup<01:08:02.880> but<01:08:03.359> with<01:08:03.539> a<01:08:03.780> different<01:08:03.900> API<01:08:04.440> just 01:08:04.730 --> 01:08:04.740 align:start position:0% same setup but with a different API just 01:08:04.740 --> 01:08:06.710 align:start position:0% same setup but with a different API just as<01:08:05.039> an<01:08:05.160> example<01:08:05.339> yeah<01:08:05.760> so<01:08:05.940> we<01:08:06.059> will<01:08:06.180> go<01:08:06.359> into<01:08:06.480> a 01:08:06.710 --> 01:08:06.720 align:start position:0% as an example yeah so we will go into a 01:08:06.720 --> 01:08:08.750 align:start position:0% as an example yeah so we will go into a more<01:08:06.839> interesting<01:08:07.200> example 01:08:08.750 --> 01:08:08.760 align:start position:0% more interesting example 01:08:08.760 --> 01:08:10.309 align:start position:0% more interesting example um<01:08:08.880> but<01:08:09.059> before<01:08:09.240> that 01:08:10.309 --> 01:08:10.319 align:start position:0% um but before that 01:08:10.319 --> 01:08:13.010 align:start position:0% um but before that um<01:08:10.440> there<01:08:10.920> is<01:08:11.099> uh<01:08:11.640> something<01:08:12.180> that<01:08:12.480> you 01:08:13.010 --> 01:08:13.020 align:start position:0% um there is uh something that you 01:08:13.020 --> 01:08:14.329 align:start position:0% um there is uh something that you wouldn't<01:08:13.140> need<01:08:13.500> which<01:08:13.859> is<01:08:13.980> called<01:08:14.160> the 01:08:14.329 --> 01:08:14.339 align:start position:0% wouldn't need which is called the 01:08:14.339 --> 01:08:16.550 align:start position:0% wouldn't need which is called the multi-aba<01:08:15.059> mode 01:08:16.550 --> 01:08:16.560 align:start position:0% multi-aba mode 01:08:16.560 --> 01:08:19.970 align:start position:0% multi-aba mode um so<01:08:17.120> we<01:08:18.120> usually<01:08:18.480> usually<01:08:18.960> testing<01:08:19.500> tools 01:08:19.970 --> 01:08:19.980 align:start position:0% um so we usually usually testing tools 01:08:19.980 --> 01:08:22.970 align:start position:0% um so we usually usually testing tools take<01:08:20.339> a<01:08:20.880> specific<01:08:21.120> contract<01:08:21.719> as<01:08:22.500> your<01:08:22.799> main 01:08:22.970 --> 01:08:22.980 align:start position:0% take a specific contract as your main 01:08:22.980 --> 01:08:26.090 align:start position:0% take a specific contract as your main contract<01:08:23.339> to<01:08:23.520> interact<01:08:23.940> so<01:08:24.779> in<01:08:25.319> in<01:08:25.500> the 01:08:26.090 --> 01:08:26.100 align:start position:0% contract to interact so in in the 01:08:26.100 --> 01:08:29.329 align:start position:0% contract to interact so in in the default<01:08:26.460> mode<01:08:26.640> echina<01:08:27.299> will<01:08:27.660> only<01:08:28.500> target<01:08:28.859> a 01:08:29.329 --> 01:08:29.339 align:start position:0% default mode echina will only target a 01:08:29.339 --> 01:08:31.010 align:start position:0% default mode echina will only target a specific<01:08:29.520> contract<01:08:29.940> that<01:08:30.120> you<01:08:30.299> can<01:08:30.420> put<01:08:30.660> in<01:08:30.779> on 01:08:31.010 --> 01:08:31.020 align:start position:0% specific contract that you can put in on 01:08:31.020 --> 01:08:33.110 align:start position:0% specific contract that you can put in on on<01:08:31.199> your<01:08:31.500> command<01:08:31.920> line<01:08:31.980> or<01:08:32.520> if<01:08:32.640> you<01:08:32.880> have<01:08:32.940> only 01:08:33.110 --> 01:08:33.120 align:start position:0% on your command line or if you have only 01:08:33.120 --> 01:08:35.150 align:start position:0% on your command line or if you have only one<01:08:33.359> contract<01:08:33.660> you<01:08:33.839> will<01:08:34.020> use<01:08:34.319> the<01:08:34.620> first<01:08:34.980> one 01:08:35.150 --> 01:08:35.160 align:start position:0% one contract you will use the first one 01:08:35.160 --> 01:08:36.890 align:start position:0% one contract you will use the first one right<01:08:35.880> but<01:08:36.239> there<01:08:36.359> is<01:08:36.540> something<01:08:36.660> called 01:08:36.890 --> 01:08:36.900 align:start position:0% right but there is something called 01:08:36.900 --> 01:08:40.370 align:start position:0% right but there is something called multi-avi<01:08:37.620> that<01:08:37.859> would<01:08:38.100> call<01:08:38.540> every<01:08:39.540> every 01:08:40.370 --> 01:08:40.380 align:start position:0% multi-avi that would call every every 01:08:40.380 --> 01:08:42.950 align:start position:0% multi-avi that would call every every contract<01:08:41.160> that<01:08:41.460> is<01:08:41.580> deployed<01:08:42.120> after<01:08:42.660> the 01:08:42.950 --> 01:08:42.960 align:start position:0% contract that is deployed after the 01:08:42.960 --> 01:08:45.530 align:start position:0% contract that is deployed after the Constructor<01:08:43.380> that<01:08:44.160> you<01:08:44.400> have<01:08:44.520> Avi<01:08:45.000> right<01:08:45.299> so 01:08:45.530 --> 01:08:45.540 align:start position:0% Constructor that you have Avi right so 01:08:45.540 --> 01:08:47.510 align:start position:0% Constructor that you have Avi right so if<01:08:45.719> you<01:08:45.779> deploy<01:08:46.080> something<01:08:46.319> in<01:08:46.560> bike<01:08:46.679> in<01:08:46.920> by 01:08:47.510 --> 01:08:47.520 align:start position:0% if you deploy something in bike in by 01:08:47.520 --> 01:08:49.910 align:start position:0% if you deploy something in bike in by code<01:08:47.819> directly<01:08:48.239> and<01:08:48.660> you<01:08:48.779> don't<01:08:49.020> have<01:08:49.140> Avi<01:08:49.560> in 01:08:49.910 --> 01:08:49.920 align:start position:0% code directly and you don't have Avi in 01:08:49.920 --> 01:08:51.470 align:start position:0% code directly and you don't have Avi in the<01:08:50.040> won't<01:08:50.160> be<01:08:50.279> able<01:08:50.460> to<01:08:50.580> call<01:08:50.940> it<01:08:51.120> because<01:08:51.299> it 01:08:51.470 --> 01:08:51.480 align:start position:0% the won't be able to call it because it 01:08:51.480 --> 01:08:53.990 align:start position:0% the won't be able to call it because it doesn't<01:08:51.600> know<01:08:51.960> what<01:08:52.380> is<01:08:52.500> what<01:08:52.859> is<01:08:52.980> there<01:08:53.160> but 01:08:53.990 --> 01:08:54.000 align:start position:0% doesn't know what is what is there but 01:08:54.000 --> 01:08:56.570 align:start position:0% doesn't know what is what is there but if<01:08:54.600> you<01:08:54.719> if<01:08:55.020> you<01:08:55.259> deployed<01:08:55.799> a<01:08:56.279> couple<01:08:56.339> of 01:08:56.570 --> 01:08:56.580 align:start position:0% if you if you deployed a couple of 01:08:56.580 --> 01:08:59.689 align:start position:0% if you if you deployed a couple of tokens<01:08:57.239> and<01:08:57.960> several<01:08:58.620> contracts<01:08:59.100> and<01:08:59.400> you<01:08:59.520> use 01:08:59.689 --> 01:08:59.699 align:start position:0% tokens and several contracts and you use 01:08:59.699 --> 01:09:02.450 align:start position:0% tokens and several contracts and you use multi<01:09:00.060> API<01:09:00.480> Echidna<01:09:01.380> will<01:09:01.500> call<01:09:01.679> any<01:09:01.980> function 01:09:02.450 --> 01:09:02.460 align:start position:0% multi API Echidna will call any function 01:09:02.460 --> 01:09:05.570 align:start position:0% multi API Echidna will call any function in<01:09:03.000> any<01:09:03.179> deploy<01:09:03.600> contract<01:09:04.080> uh<01:09:04.920> after<01:09:05.160> after 01:09:05.570 --> 01:09:05.580 align:start position:0% in any deploy contract uh after after 01:09:05.580 --> 01:09:08.930 align:start position:0% in any deploy contract uh after after the<01:09:06.120> the<01:09:06.540> end<01:09:07.140> of<01:09:07.319> the<01:09:07.380> Constructor<01:09:07.799> so<01:09:08.640> we 01:09:08.930 --> 01:09:08.940 align:start position:0% the the end of the Constructor so we 01:09:08.940 --> 01:09:10.970 align:start position:0% the the end of the Constructor so we will<01:09:09.179> need<01:09:09.540> these<01:09:10.140> in<01:09:10.259> order<01:09:10.440> to<01:09:10.620> deal<01:09:10.799> with 01:09:10.970 --> 01:09:10.980 align:start position:0% will need these in order to deal with 01:09:10.980 --> 01:09:13.430 align:start position:0% will need these in order to deal with the<01:09:11.160> next<01:09:11.279> example<01:09:11.759> because<01:09:12.000> sometimes<01:09:12.600> the 01:09:13.430 --> 01:09:13.440 align:start position:0% the next example because sometimes the 01:09:13.440 --> 01:09:16.070 align:start position:0% the next example because sometimes the the<01:09:13.920> the<01:09:14.100> the<01:09:14.580> debug<01:09:15.299> that<01:09:15.480> you<01:09:15.660> want<01:09:15.900> to 01:09:16.070 --> 01:09:16.080 align:start position:0% the the the debug that you want to 01:09:16.080 --> 01:09:18.709 align:start position:0% the the the debug that you want to detect<01:09:16.620> it<01:09:17.160> doesn't<01:09:17.279> depend<01:09:17.759> on<01:09:18.179> the<01:09:18.359> state<01:09:18.600> of 01:09:18.709 --> 01:09:18.719 align:start position:0% detect it doesn't depend on the state of 01:09:18.719 --> 01:09:20.269 align:start position:0% detect it doesn't depend on the state of one<01:09:18.900> contract<01:09:19.319> it<01:09:19.500> depends<01:09:19.739> on<01:09:19.799> the<01:09:19.920> state<01:09:20.100> of 01:09:20.269 --> 01:09:20.279 align:start position:0% one contract it depends on the state of 01:09:20.279 --> 01:09:23.269 align:start position:0% one contract it depends on the state of many<01:09:20.460> contracts<01:09:21.080> and<01:09:22.080> in<01:09:22.440> that<01:09:22.620> case<01:09:22.799> you<01:09:23.160> can 01:09:23.269 --> 01:09:23.279 align:start position:0% many contracts and in that case you can 01:09:23.279 --> 01:09:25.729 align:start position:0% many contracts and in that case you can you<01:09:23.940> can<01:09:24.179> be<01:09:24.420> surprised<01:09:24.900> by<01:09:25.140> the<01:09:25.319> fact<01:09:25.440> that 01:09:25.729 --> 01:09:25.739 align:start position:0% you can be surprised by the fact that 01:09:25.739 --> 01:09:28.070 align:start position:0% you can be surprised by the fact that changing<01:09:26.520> the<01:09:26.699> state<01:09:26.940> in<01:09:27.299> another<01:09:27.480> contract 01:09:28.070 --> 01:09:28.080 align:start position:0% changing the state in another contract 01:09:28.080 --> 01:09:30.950 align:start position:0% changing the state in another contract can<01:09:28.859> break<01:09:29.460> your<01:09:29.699> your<01:09:30.179> property<01:09:30.600> and 01:09:30.950 --> 01:09:30.960 align:start position:0% can break your your property and 01:09:30.960 --> 01:09:33.050 align:start position:0% can break your your property and definitely<01:09:31.319> we<01:09:31.560> want<01:09:31.739> to<01:09:31.859> avoid<01:09:32.219> that 01:09:33.050 --> 01:09:33.060 align:start position:0% definitely we want to avoid that 01:09:33.060 --> 01:09:34.849 align:start position:0% definitely we want to avoid that Okay<01:09:33.779> so 01:09:34.849 --> 01:09:34.859 align:start position:0% Okay so 01:09:34.859 --> 01:09:37.849 align:start position:0% Okay so uh<01:09:35.699> again<01:09:35.880> how<01:09:36.179> many<01:09:36.299> of<01:09:36.480> you<01:09:36.660> know<01:09:36.960> about<01:09:37.259> them 01:09:37.849 --> 01:09:37.859 align:start position:0% uh again how many of you know about them 01:09:37.859 --> 01:09:39.769 align:start position:0% uh again how many of you know about them vulnerable<01:09:38.279> defy 01:09:39.769 --> 01:09:39.779 align:start position:0% vulnerable defy 01:09:39.779 --> 01:09:42.709 align:start position:0% vulnerable defy okay<01:09:40.380> a<01:09:40.739> good<01:09:41.040> number<01:09:41.160> and<01:09:41.940> did<01:09:42.179> you<01:09:42.359> actually 01:09:42.709 --> 01:09:42.719 align:start position:0% okay a good number and did you actually 01:09:42.719 --> 01:09:44.390 align:start position:0% okay a good number and did you actually well<01:09:43.380> this<01:09:43.560> is<01:09:43.679> these<01:09:43.980> are<01:09:44.100> the<01:09:44.279> first 01:09:44.390 --> 01:09:44.400 align:start position:0% well this is these are the first 01:09:44.400 --> 01:09:47.990 align:start position:0% well this is these are the first exercise<01:09:44.699> the<01:09:45.120> first<01:09:45.420> the<01:09:45.719> first<01:09:46.020> two<01:09:46.400> uh<01:09:47.400> so<01:09:47.699> I 01:09:47.990 --> 01:09:48.000 align:start position:0% exercise the first the first two uh so I 01:09:48.000 --> 01:09:51.110 align:start position:0% exercise the first the first two uh so I hope<01:09:48.179> that<01:09:48.540> uh<01:09:49.380> uh<01:09:50.040> people<01:09:50.160> know<01:09:50.400> so<01:09:50.640> if<01:09:50.940> you 01:09:51.110 --> 01:09:51.120 align:start position:0% hope that uh uh people know so if you 01:09:51.120 --> 01:09:53.870 align:start position:0% hope that uh uh people know so if you know<01:09:51.299> this<01:09:51.600> this<01:09:51.960> how<01:09:52.319> to<01:09:52.500> solve<01:09:52.799> it<01:09:52.920> you 01:09:53.870 --> 01:09:53.880 align:start position:0% know this this how to solve it you 01:09:53.880 --> 01:09:56.209 align:start position:0% know this this how to solve it you should<01:09:54.239> uh<01:09:54.719> it's<01:09:55.020> going<01:09:55.140> to<01:09:55.320> be<01:09:55.440> even<01:09:55.739> easier 01:09:56.209 --> 01:09:56.219 align:start position:0% should uh it's going to be even easier 01:09:56.219 --> 01:09:58.310 align:start position:0% should uh it's going to be even easier uh<01:09:56.940> for<01:09:57.120> you<01:09:57.239> what<01:09:57.480> we're<01:09:57.600> going<01:09:57.780> to<01:09:57.900> do<01:09:58.080> is 01:09:58.310 --> 01:09:58.320 align:start position:0% uh for you what we're going to do is 01:09:58.320 --> 01:10:02.209 align:start position:0% uh for you what we're going to do is we're<01:09:58.980> going<01:09:59.280> to<01:09:59.520> uh<01:10:00.480> take<01:10:00.780> a<01:10:00.900> look<01:10:01.020> of<01:10:01.260> this 01:10:02.209 --> 01:10:02.219 align:start position:0% we're going to uh take a look of this 01:10:02.219 --> 01:10:04.669 align:start position:0% we're going to uh take a look of this um<01:10:02.280> sample<01:10:02.880> so<01:10:03.120> yeah 01:10:04.669 --> 01:10:04.679 align:start position:0% um sample so yeah 01:10:04.679 --> 01:10:06.950 align:start position:0% um sample so yeah I<01:10:05.520> assume<01:10:06.000> that<01:10:06.060> we<01:10:06.300> already<01:10:06.420> you<01:10:06.719> already 01:10:06.950 --> 01:10:06.960 align:start position:0% I assume that we already you already 01:10:06.960 --> 01:10:08.750 align:start position:0% I assume that we already you already have<01:10:07.140> a<01:10:07.320> code 01:10:08.750 --> 01:10:08.760 align:start position:0% have a code 01:10:08.760 --> 01:10:10.130 align:start position:0% have a code so 01:10:10.130 --> 01:10:10.140 align:start position:0% so 01:10:10.140 --> 01:10:11.810 align:start position:0% so um<01:10:10.199> is<01:10:10.620> the 01:10:11.810 --> 01:10:11.820 align:start position:0% um is the 01:10:11.820 --> 01:10:16.669 align:start position:0% um is the exercise<01:10:12.800> the<01:10:13.800> the<01:10:14.100> naive<01:10:14.460> receiver<01:10:14.880> one 01:10:16.669 --> 01:10:16.679 align:start position:0% exercise the the naive receiver one 01:10:16.679 --> 01:10:19.550 align:start position:0% exercise the the naive receiver one um<01:10:16.860> so<01:10:17.340> what<01:10:17.580> we<01:10:17.760> want<01:10:18.000> to<01:10:18.179> do<01:10:18.360> is 01:10:19.550 --> 01:10:19.560 align:start position:0% um so what we want to do is 01:10:19.560 --> 01:10:22.430 align:start position:0% um so what we want to do is we<01:10:19.980> want<01:10:20.100> to<01:10:20.219> be<01:10:20.280> able<01:10:20.400> to<01:10:20.580> drain 01:10:22.430 --> 01:10:22.440 align:start position:0% we want to be able to drain 01:10:22.440 --> 01:10:26.810 align:start position:0% we want to be able to drain um<01:10:22.620> the<01:10:23.340> the<01:10:23.640> funds<01:10:24.300> in<01:10:24.900> Flash<01:10:25.140> loan<01:10:25.620> receiver 01:10:26.810 --> 01:10:26.820 align:start position:0% um the the funds in Flash loan receiver 01:10:26.820 --> 01:10:29.270 align:start position:0% um the the funds in Flash loan receiver right<01:10:27.300> just<01:10:27.780> to<01:10:28.080> give<01:10:28.260> like<01:10:28.500> a<01:10:28.800> bit<01:10:29.159> of 01:10:29.270 --> 01:10:29.280 align:start position:0% right just to give like a bit of 01:10:29.280 --> 01:10:32.090 align:start position:0% right just to give like a bit of description<01:10:29.640> of<01:10:29.940> the<01:10:30.060> of<01:10:30.300> the<01:10:30.600> challenge 01:10:32.090 --> 01:10:32.100 align:start position:0% description of the of the challenge 01:10:32.100 --> 01:10:34.010 align:start position:0% description of the of the challenge um<01:10:32.159> here<01:10:32.400> you<01:10:32.520> have<01:10:32.640> two<01:10:32.880> contract<01:10:33.300> you<01:10:33.840> have 01:10:34.010 --> 01:10:34.020 align:start position:0% um here you have two contract you have 01:10:34.020 --> 01:10:35.030 align:start position:0% um here you have two contract you have the<01:10:34.199> naive 01:10:35.030 --> 01:10:35.040 align:start position:0% the naive 01:10:35.040 --> 01:10:37.250 align:start position:0% the naive um<01:10:35.100> we<01:10:35.699> see<01:10:35.940> the<01:10:36.060> Orlando<01:10:36.179> pool<01:10:36.719> which 01:10:37.250 --> 01:10:37.260 align:start position:0% um we see the Orlando pool which 01:10:37.260 --> 01:10:41.570 align:start position:0% um we see the Orlando pool which basically<01:10:37.739> yeah<01:10:38.159> yeah<01:10:38.699> it's<01:10:39.179> it's<01:10:39.420> over<01:10:39.840> there 01:10:41.570 --> 01:10:41.580 align:start position:0% basically yeah yeah it's it's over there 01:10:41.580 --> 01:10:43.370 align:start position:0% basically yeah yeah it's it's over there um I<01:10:42.000> can<01:10:42.120> allow<01:10:42.480> you<01:10:42.540> to<01:10:42.719> take<01:10:42.840> a<01:10:43.020> Flash<01:10:43.140> run 01:10:43.370 --> 01:10:43.380 align:start position:0% um I can allow you to take a Flash run 01:10:43.380 --> 01:10:45.950 align:start position:0% um I can allow you to take a Flash run for<01:10:43.620> a<01:10:43.800> fee<01:10:43.980> and<01:10:44.760> you<01:10:44.940> have<01:10:45.060> a<01:10:45.179> second<01:10:45.360> contract 01:10:45.950 --> 01:10:45.960 align:start position:0% for a fee and you have a second contract 01:10:45.960 --> 01:10:49.189 align:start position:0% for a fee and you have a second contract which<01:10:46.620> is<01:10:46.739> a<01:10:46.920> user<01:10:47.340> uh<01:10:48.120> contract<01:10:48.480> that<01:10:49.080> is 01:10:49.189 --> 01:10:49.199 align:start position:0% which is a user uh contract that is 01:10:49.199 --> 01:10:52.669 align:start position:0% which is a user uh contract that is going<01:10:49.380> to<01:10:49.500> interact<01:10:49.920> with<01:10:50.159> a<01:10:50.640> pool<01:10:51.440> and<01:10:52.440> the 01:10:52.669 --> 01:10:52.679 align:start position:0% going to interact with a pool and the 01:10:52.679 --> 01:10:53.930 align:start position:0% going to interact with a pool and the contract<01:10:52.920> is<01:10:53.100> going<01:10:53.280> to<01:10:53.340> be<01:10:53.460> the<01:10:53.580> user 01:10:53.930 --> 01:10:53.940 align:start position:0% contract is going to be the user 01:10:53.940 --> 01:10:55.250 align:start position:0% contract is going to be the user contract<01:10:54.239> is<01:10:54.360> going<01:10:54.540> to<01:10:54.600> be<01:10:54.719> deployed<01:10:55.140> with 01:10:55.250 --> 01:10:55.260 align:start position:0% contract is going to be deployed with 01:10:55.260 --> 01:10:57.410 align:start position:0% contract is going to be deployed with some<01:10:55.440> fund<01:10:55.860> inside<01:10:56.040> and<01:10:56.760> the<01:10:56.880> girl<01:10:57.060> is<01:10:57.239> going 01:10:57.410 --> 01:10:57.420 align:start position:0% some fund inside and the girl is going 01:10:57.420 --> 01:11:00.350 align:start position:0% some fund inside and the girl is going to<01:10:57.540> try<01:10:57.780> to<01:10:57.960> see<01:10:58.260> if<01:10:58.980> it's<01:10:59.159> possible<01:10:59.640> for<01:11:00.120> this 01:11:00.350 --> 01:11:00.360 align:start position:0% to try to see if it's possible for this 01:11:00.360 --> 01:11:01.910 align:start position:0% to try to see if it's possible for this specific<01:11:00.659> contract<01:11:01.080> from<01:11:01.320> the<01:11:01.440> user<01:11:01.620> to<01:11:01.800> be 01:11:01.910 --> 01:11:01.920 align:start position:0% specific contract from the user to be 01:11:01.920 --> 01:11:03.229 align:start position:0% specific contract from the user to be joined 01:11:03.229 --> 01:11:03.239 align:start position:0% joined 01:11:03.239 --> 01:11:09.110 align:start position:0% joined exactly<01:11:03.960> so 01:11:09.110 --> 01:11:09.120 align:start position:0% 01:11:09.120 --> 01:11:13.970 align:start position:0% uh<01:11:09.960> we<01:11:10.320> we<01:11:10.620> want<01:11:10.920> you<01:11:11.040> to<01:11:11.340> review<01:11:11.940> the<01:11:12.480> the 01:11:13.970 --> 01:11:13.980 align:start position:0% uh we we want you to review the the 01:11:13.980 --> 01:11:16.250 align:start position:0% uh we we want you to review the the um<01:11:14.040> the<01:11:14.340> exercise<01:11:14.520> if<01:11:15.060> you<01:11:15.179> have<01:11:15.360> already<01:11:15.600> did 01:11:16.250 --> 01:11:16.260 align:start position:0% um the exercise if you have already did 01:11:16.260 --> 01:11:19.430 align:start position:0% um the exercise if you have already did it<01:11:16.500> it<01:11:17.159> requires<01:11:18.000> you<01:11:18.060> to<01:11:18.239> send<01:11:18.480> some<01:11:18.900> some 01:11:19.430 --> 01:11:19.440 align:start position:0% it it requires you to send some some 01:11:19.440 --> 01:11:22.910 align:start position:0% it it requires you to send some some some<01:11:19.560> some<01:11:19.920> number<01:11:20.580> of<01:11:20.760> transactions<01:11:21.360> so<01:11:22.260> in 01:11:22.910 --> 01:11:22.920 align:start position:0% some some number of transactions so in 01:11:22.920 --> 01:11:24.350 align:start position:0% some some number of transactions so in this<01:11:23.040> case<01:11:23.219> we<01:11:23.580> are<01:11:23.699> going<01:11:23.820> to<01:11:24.000> prepare 01:11:24.350 --> 01:11:24.360 align:start position:0% this case we are going to prepare 01:11:24.360 --> 01:11:26.649 align:start position:0% this case we are going to prepare everything<01:11:24.600> for<01:11:25.020> a<01:11:25.199> kidnap<01:11:25.679> to<01:11:25.980> ReDiscover 01:11:26.649 --> 01:11:26.659 align:start position:0% everything for a kidnap to ReDiscover 01:11:26.659 --> 01:11:32.090 align:start position:0% everything for a kidnap to ReDiscover this<01:11:27.659> without<01:11:28.760> telling<01:11:29.760> it<01:11:29.940> what<01:11:30.540> is<01:11:30.719> what<01:11:31.679> uh 01:11:32.090 --> 01:11:32.100 align:start position:0% this without telling it what is what uh 01:11:32.100 --> 01:11:36.290 align:start position:0% this without telling it what is what uh how<01:11:32.340> how<01:11:32.760> it<01:11:33.120> can<01:11:33.300> be<01:11:33.540> uh<01:11:34.500> sold<01:11:35.159> so<01:11:35.760> we<01:11:36.120> will 01:11:36.290 --> 01:11:36.300 align:start position:0% how how it can be uh sold so we will 01:11:36.300 --> 01:11:37.729 align:start position:0% how how it can be uh sold so we will need<01:11:36.480> two<01:11:36.659> things<01:11:36.840> we<01:11:37.199> will<01:11:37.320> need<01:11:37.500> to 01:11:37.729 --> 01:11:37.739 align:start position:0% need two things we will need to 01:11:37.739 --> 01:11:40.430 align:start position:0% need two things we will need to initialize<01:11:38.400> the 01:11:40.430 --> 01:11:40.440 align:start position:0% initialize the 01:11:40.440 --> 01:11:42.470 align:start position:0% initialize the um<01:11:40.500> the<01:11:40.860> code<01:11:41.040> to<01:11:41.699> have 01:11:42.470 --> 01:11:42.480 align:start position:0% um the code to have 01:11:42.480 --> 01:11:45.410 align:start position:0% um the code to have um<01:11:42.540> too<01:11:43.020> much<01:11:43.199> what<01:11:44.100> the<01:11:44.460> what<01:11:45.239> the 01:11:45.410 --> 01:11:45.420 align:start position:0% um too much what the what the 01:11:45.420 --> 01:11:47.450 align:start position:0% um too much what the what the initialization<01:11:45.900> is<01:11:46.320> it's 01:11:47.450 --> 01:11:47.460 align:start position:0% initialization is it's 01:11:47.460 --> 01:11:50.630 align:start position:0% initialization is it's um is<01:11:48.000> actually<01:11:48.199> showing<01:11:49.199> us<01:11:49.380> let's<01:11:49.679> see 01:11:50.630 --> 01:11:50.640 align:start position:0% um is actually showing us let's see 01:11:50.640 --> 01:11:53.750 align:start position:0% um is actually showing us let's see okay<01:11:51.300> so<01:11:51.719> this<01:11:51.900> is<01:11:52.020> the<01:11:52.199> The<01:11:52.380> Flash<01:11:52.620> loan<01:11:53.100> uh 01:11:53.750 --> 01:11:53.760 align:start position:0% okay so this is the The Flash loan uh 01:11:53.760 --> 01:11:56.030 align:start position:0% okay so this is the The Flash loan uh the<01:11:53.880> part<01:11:54.060> of<01:11:54.179> the<01:11:54.300> or<01:11:54.480> the<01:11:54.659> flash<01:11:54.780> loan<01:11:55.199> so<01:11:55.800> the 01:11:56.030 --> 01:11:56.040 align:start position:0% the part of the or the flash loan so the 01:11:56.040 --> 01:11:57.890 align:start position:0% the part of the or the flash loan so the the<01:11:56.400> interesting<01:11:56.880> part<01:11:57.060> about<01:11:57.179> this<01:11:57.480> is<01:11:57.600> we 01:11:57.890 --> 01:11:57.900 align:start position:0% the interesting part about this is we 01:11:57.900 --> 01:11:59.510 align:start position:0% the interesting part about this is we don't<01:11:58.020> have<01:11:58.260> to<01:11:58.500> care<01:11:58.739> about<01:11:58.920> specific 01:11:59.510 --> 01:11:59.520 align:start position:0% don't have to care about specific 01:11:59.520 --> 01:12:02.689 align:start position:0% don't have to care about specific details<01:12:00.060> in<01:12:00.179> the<01:12:00.360> code<01:12:00.480> we<01:12:01.260> want<01:12:01.560> to<01:12:01.800> we<01:12:02.520> want 01:12:02.689 --> 01:12:02.699 align:start position:0% details in the code we want to we want 01:12:02.699 --> 01:12:03.590 align:start position:0% details in the code we want to we want to 01:12:03.590 --> 01:12:03.600 align:start position:0% to 01:12:03.600 --> 01:12:05.750 align:start position:0% to um<01:12:03.659> give<01:12:04.140> a<01:12:04.320> kid<01:12:04.440> now<01:12:04.620> the<01:12:04.920> same<01:12:05.040> scenario<01:12:05.460> that 01:12:05.750 --> 01:12:05.760 align:start position:0% um give a kid now the same scenario that 01:12:05.760 --> 01:12:08.270 align:start position:0% um give a kid now the same scenario that we<01:12:05.940> have<01:12:06.120> on<01:12:06.420> the<01:12:06.600> on<01:12:07.080> the<01:12:07.320> actual<01:12:07.679> uh 01:12:08.270 --> 01:12:08.280 align:start position:0% we have on the on the actual uh 01:12:08.280 --> 01:12:11.149 align:start position:0% we have on the on the actual uh Challenge<01:12:08.580> and<01:12:09.300> we<01:12:09.540> want<01:12:09.719> to<01:12:09.900> know<01:12:10.140> if<01:12:10.560> it<01:12:10.860> can 01:12:11.149 --> 01:12:11.159 align:start position:0% Challenge and we want to know if it can 01:12:11.159 --> 01:12:14.510 align:start position:0% Challenge and we want to know if it can actually<01:12:12.060> find<01:12:12.780> a<01:12:13.020> way<01:12:13.199> to<01:12:13.739> drain<01:12:14.340> the 01:12:14.510 --> 01:12:14.520 align:start position:0% actually find a way to drain the 01:12:14.520 --> 01:12:15.470 align:start position:0% actually find a way to drain the contract 01:12:15.470 --> 01:12:15.480 align:start position:0% contract 01:12:15.480 --> 01:12:19.370 align:start position:0% contract so<01:12:16.320> yeah<01:12:16.620> we<01:12:16.920> can<01:12:17.100> uh<01:12:17.699> we<01:12:18.000> can<01:12:18.120> see<01:12:18.480> uh<01:12:19.020> how<01:12:19.199> the 01:12:19.370 --> 01:12:19.380 align:start position:0% so yeah we can uh we can see uh how the 01:12:19.380 --> 01:12:21.470 align:start position:0% so yeah we can uh we can see uh how the reciprocal<01:12:20.100> function 01:12:21.470 --> 01:12:21.480 align:start position:0% reciprocal function 01:12:21.480 --> 01:12:23.930 align:start position:0% reciprocal function um<01:12:21.600> works<01:12:22.199> here<01:12:22.380> but<01:12:23.400> um<01:12:23.460> yeah<01:12:23.699> the 01:12:23.930 --> 01:12:23.940 align:start position:0% um works here but um yeah the 01:12:23.940 --> 01:12:25.669 align:start position:0% um works here but um yeah the interesting<01:12:24.600> part<01:12:24.960> perhaps<01:12:25.380> is<01:12:25.560> the 01:12:25.669 --> 01:12:25.679 align:start position:0% interesting part perhaps is the 01:12:25.679 --> 01:12:27.950 align:start position:0% interesting part perhaps is the initialization<01:12:26.179> what<01:12:27.179> we<01:12:27.300> are<01:12:27.420> going<01:12:27.540> to<01:12:27.719> do 01:12:27.950 --> 01:12:27.960 align:start position:0% initialization what we are going to do 01:12:27.960 --> 01:12:30.590 align:start position:0% initialization what we are going to do is<01:12:28.260> we<01:12:28.800> are<01:12:28.980> going<01:12:29.159> to<01:12:29.460> deploy<01:12:30.300> in<01:12:30.420> the 01:12:30.590 --> 01:12:30.600 align:start position:0% is we are going to deploy in the 01:12:30.600 --> 01:12:32.689 align:start position:0% is we are going to deploy in the Constructor<01:12:30.960> of<01:12:31.500> our 01:12:32.689 --> 01:12:32.699 align:start position:0% Constructor of our 01:12:32.699 --> 01:12:36.050 align:start position:0% Constructor of our um test<01:12:33.480> we're<01:12:33.960> going<01:12:34.199> to<01:12:34.320> deploy<01:12:34.860> the<01:12:35.820> the 01:12:36.050 --> 01:12:36.060 align:start position:0% um test we're going to deploy the the 01:12:36.060 --> 01:12:38.149 align:start position:0% um test we're going to deploy the the contracts<01:12:36.600> that<01:12:36.780> we<01:12:36.960> have<01:12:37.140> here<01:12:37.440> and<01:12:37.800> prepare 01:12:38.149 --> 01:12:38.159 align:start position:0% contracts that we have here and prepare 01:12:38.159 --> 01:12:40.790 align:start position:0% contracts that we have here and prepare everything<01:12:38.340> and<01:12:39.239> then<01:12:39.360> we're<01:12:39.540> going<01:12:39.780> to<01:12:39.960> use<01:12:40.500> a 01:12:40.790 --> 01:12:40.800 align:start position:0% everything and then we're going to use a 01:12:40.800 --> 01:12:42.530 align:start position:0% everything and then we're going to use a suitable 01:12:42.530 --> 01:12:42.540 align:start position:0% suitable 01:12:42.540 --> 01:12:44.930 align:start position:0% suitable um<01:12:42.600> uh<01:12:43.140> invariant<01:12:43.679> which<01:12:44.100> should<01:12:44.520> be<01:12:44.699> really 01:12:44.930 --> 01:12:44.940 align:start position:0% um uh invariant which should be really 01:12:44.940 --> 01:12:48.530 align:start position:0% um uh invariant which should be really simple<01:12:45.120> you<01:12:45.420> don't<01:12:45.600> have<01:12:45.840> to<01:12:46.400> overthink<01:12:47.540> and 01:12:48.530 --> 01:12:48.540 align:start position:0% simple you don't have to overthink and 01:12:48.540 --> 01:12:52.490 align:start position:0% simple you don't have to overthink and we<01:12:49.199> want<01:12:49.500> you<01:12:49.679> to<01:12:50.100> uh<01:12:51.000> run<01:12:51.239> a<01:12:51.360> kidnap<01:12:51.840> uh<01:12:52.260> with 01:12:52.490 --> 01:12:52.500 align:start position:0% we want you to uh run a kidnap uh with 01:12:52.500 --> 01:12:55.250 align:start position:0% we want you to uh run a kidnap uh with that<01:12:52.679> in<01:12:53.040> order<01:12:53.159> to<01:12:53.460> see<01:12:53.820> if<01:12:54.480> it<01:12:54.659> can<01:12:54.780> drain<01:12:55.020> the 01:12:55.250 --> 01:12:55.260 align:start position:0% that in order to see if it can drain the 01:12:55.260 --> 01:12:57.169 align:start position:0% that in order to see if it can drain the contract<01:12:55.560> uh<01:12:55.980> with<01:12:56.280> the<01:12:56.400> of<01:12:56.699> course<01:12:56.760> with<01:12:57.000> a 01:12:57.169 --> 01:12:57.179 align:start position:0% contract uh with the of course with a 01:12:57.179 --> 01:12:58.189 align:start position:0% contract uh with the of course with a suitable 01:12:58.189 --> 01:12:58.199 align:start position:0% suitable 01:12:58.199 --> 01:13:00.410 align:start position:0% suitable um<01:12:58.260> uh<01:12:58.679> with<01:12:58.860> a<01:12:58.980> suitable<01:12:59.219> invariant<01:12:59.820> so<01:13:00.300> yeah 01:13:00.410 --> 01:13:00.420 align:start position:0% um uh with a suitable invariant so yeah 01:13:00.420 --> 01:13:01.970 align:start position:0% um uh with a suitable invariant so yeah we<01:13:00.659> will<01:13:00.900> take 01:13:01.970 --> 01:13:01.980 align:start position:0% we will take 01:13:01.980 --> 01:13:04.850 align:start position:0% we will take um<01:13:02.100> 10<01:13:02.280> minutes<01:13:02.520> I<01:13:02.760> think<01:13:02.880> yeah<01:13:03.320> yeah<01:13:04.320> we<01:13:04.679> are 01:13:04.850 --> 01:13:04.860 align:start position:0% um 10 minutes I think yeah yeah we are 01:13:04.860 --> 01:13:08.570 align:start position:0% um 10 minutes I think yeah yeah we are running<01:13:05.640> out<01:13:05.940> of<01:13:06.120> time<01:13:06.239> but<01:13:06.600> uh<01:13:07.500> let's<01:13:08.100> take<01:13:08.340> 10 01:13:08.570 --> 01:13:08.580 align:start position:0% running out of time but uh let's take 10 01:13:08.580 --> 01:13:10.729 align:start position:0% running out of time but uh let's take 10 minutes<01:13:08.880> so<01:13:09.659> the<01:13:09.840> first<01:13:10.080> step<01:13:10.199> is<01:13:10.380> really<01:13:10.560> like 01:13:10.729 --> 01:13:10.739 align:start position:0% minutes so the first step is really like 01:13:10.739 --> 01:13:12.770 align:start position:0% minutes so the first step is really like this<01:13:11.040> is<01:13:11.159> a<01:13:11.400> initialization<01:13:12.060> from<01:13:12.480> the<01:13:12.600> test 01:13:12.770 --> 01:13:12.780 align:start position:0% this is a initialization from the test 01:13:12.780 --> 01:13:14.689 align:start position:0% this is a initialization from the test case<01:13:13.020> of<01:13:13.260> the<01:13:13.380> contract<01:13:13.739> the<01:13:14.159> first<01:13:14.400> step<01:13:14.580> is 01:13:14.689 --> 01:13:14.699 align:start position:0% case of the contract the first step is 01:13:14.699 --> 01:13:16.790 align:start position:0% case of the contract the first step is really<01:13:14.880> just<01:13:15.120> to<01:13:15.239> reply<01:13:15.420> like<01:13:15.900> this<01:13:16.199> into<01:13:16.560> a 01:13:16.790 --> 01:13:16.800 align:start position:0% really just to reply like this into a 01:13:16.800 --> 01:13:18.950 align:start position:0% really just to reply like this into a solidity<01:13:17.219> Constructor<01:13:17.699> and<01:13:18.360> then<01:13:18.540> provide 01:13:18.950 --> 01:13:18.960 align:start position:0% solidity Constructor and then provide 01:13:18.960 --> 01:13:22.850 align:start position:0% solidity Constructor and then provide the<01:13:19.080> environment 01:13:22.850 --> 01:13:22.860 align:start position:0% 01:13:22.860 --> 01:13:24.350 align:start position:0% yeah<01:13:23.340> so<01:13:23.460> happy<01:13:23.699> to<01:13:23.940> take<01:13:24.000> question<01:13:24.300> questions 01:13:24.350 --> 01:13:24.360 align:start position:0% yeah so happy to take question questions 01:13:24.360 --> 01:13:31.910 align:start position:0% yeah so happy to take question questions or<01:13:24.719> any<01:13:24.900> technical<01:13:25.380> issues 01:13:31.910 --> 01:13:31.920 align:start position:0% 01:13:31.920 --> 01:13:34.490 align:start position:0% that's<01:13:32.820> a<01:13:33.179> goal<01:13:33.420> actually<01:13:33.480> we<01:13:34.080> are<01:13:34.260> going<01:13:34.320> to 01:13:34.490 --> 01:13:34.500 align:start position:0% that's a goal actually we are going to 01:13:34.500 --> 01:13:37.130 align:start position:0% that's a goal actually we are going to do<01:13:35.219> exactly<01:13:35.520> what<01:13:35.699> he's<01:13:35.940> doing<01:13:36.239> here<01:13:36.719> but<01:13:36.960> in 01:13:37.130 --> 01:13:37.140 align:start position:0% do exactly what he's doing here but in 01:13:37.140 --> 01:13:38.750 align:start position:0% do exactly what he's doing here but in serenity 01:13:38.750 --> 01:13:38.760 align:start position:0% serenity 01:13:38.760 --> 01:13:41.689 align:start position:0% serenity there<01:13:39.300> there<01:13:39.440> is<01:13:40.440> an<01:13:40.739> alternative<01:13:41.100> way<01:13:41.340> to<01:13:41.520> do 01:13:41.689 --> 01:13:41.699 align:start position:0% there there is an alternative way to do 01:13:41.699 --> 01:13:43.790 align:start position:0% there there is an alternative way to do it<01:13:41.820> but<01:13:42.060> the<01:13:42.239> solidity<01:13:42.719> approach<01:13:43.140> is<01:13:43.560> is 01:13:43.790 --> 01:13:43.800 align:start position:0% it but the solidity approach is is 01:13:43.800 --> 01:13:46.250 align:start position:0% it but the solidity approach is is easier<01:13:44.340> to<01:13:44.640> to<01:13:44.880> avoid 01:13:46.250 --> 01:13:46.260 align:start position:0% easier to to avoid 01:13:46.260 --> 01:13:48.050 align:start position:0% easier to to avoid um<01:13:46.380> because<01:13:46.800> well<01:13:47.100> the<01:13:47.400> other<01:13:47.460> tool<01:13:47.760> is<01:13:47.880> called 01:13:48.050 --> 01:13:48.060 align:start position:0% um because well the other tool is called 01:13:48.060 --> 01:13:50.390 align:start position:0% um because well the other tool is called atino<01:13:48.600> that<01:13:48.900> can<01:13:49.020> replay<01:13:49.320> this 01:13:50.390 --> 01:13:50.400 align:start position:0% atino that can replay this 01:13:50.400 --> 01:13:52.550 align:start position:0% atino that can replay this in<01:13:50.940> a<01:13:51.060> simulated<01:13:51.360> blockchain<01:13:51.780> like<01:13:52.020> ganache 01:13:52.550 --> 01:13:52.560 align:start position:0% in a simulated blockchain like ganache 01:13:52.560 --> 01:13:55.669 align:start position:0% in a simulated blockchain like ganache and<01:13:52.920> then<01:13:53.040> send<01:13:53.280> it<01:13:53.460> to<01:13:53.640> the<01:13:53.880> to<01:13:54.360> the<01:13:54.600> tool<01:13:54.900> so 01:13:55.669 --> 01:13:55.679 align:start position:0% and then send it to the to the tool so 01:13:55.679 --> 01:13:57.890 align:start position:0% and then send it to the to the tool so uh<01:13:56.280> in<01:13:56.580> that<01:13:56.699> case<01:13:56.880> you<01:13:57.300> don't<01:13:57.420> need<01:13:57.659> to 01:13:57.890 --> 01:13:57.900 align:start position:0% uh in that case you don't need to 01:13:57.900 --> 01:14:01.850 align:start position:0% uh in that case you don't need to replace<01:13:58.340> on<01:13:59.340> solidity<01:13:59.940> manually<01:14:00.659> but<01:14:01.440> you<01:14:01.679> are 01:14:01.850 --> 01:14:01.860 align:start position:0% replace on solidity manually but you are 01:14:01.860 --> 01:14:03.890 align:start position:0% replace on solidity manually but you are still<01:14:02.040> I<01:14:02.219> still<01:14:02.460> know<01:14:02.699> still<01:14:03.179> need<01:14:03.480> to<01:14:03.659> know 01:14:03.890 --> 01:14:03.900 align:start position:0% still I still know still need to know 01:14:03.900 --> 01:14:06.709 align:start position:0% still I still know still need to know where<01:14:04.800> is<01:14:05.040> everything<01:14:05.280> deployed<01:14:05.940> right<01:14:06.300> so<01:14:06.600> if 01:14:06.709 --> 01:14:06.719 align:start position:0% where is everything deployed right so if 01:14:06.719 --> 01:14:08.090 align:start position:0% where is everything deployed right so if you<01:14:06.840> want<01:14:06.960> to<01:14:07.080> interact<01:14:07.440> with<01:14:07.560> the<01:14:07.679> pool<01:14:07.800> you 01:14:08.090 --> 01:14:08.100 align:start position:0% you want to interact with the pool you 01:14:08.100 --> 01:14:09.830 align:start position:0% you want to interact with the pool you need<01:14:08.219> to<01:14:08.340> know<01:14:08.460> where<01:14:08.820> is<01:14:08.940> which<01:14:09.420> is<01:14:09.719> the 01:14:09.830 --> 01:14:09.840 align:start position:0% need to know where is which is the 01:14:09.840 --> 01:14:12.770 align:start position:0% need to know where is which is the address<01:14:09.960> of<01:14:10.260> the<01:14:10.380> pool<01:14:10.520> and<01:14:11.520> you<01:14:11.940> can<01:14:12.060> you<01:14:12.659> can 01:14:12.770 --> 01:14:12.780 align:start position:0% address of the pool and you can you can 01:14:12.780 --> 01:14:16.189 align:start position:0% address of the pool and you can you can then<01:14:13.080> uh<01:14:14.040> a<01:14:14.460> kidney<01:14:14.760> cannot<01:14:15.239> actually<01:14:15.659> call 01:14:16.189 --> 01:14:16.199 align:start position:0% then uh a kidney cannot actually call 01:14:16.199 --> 01:14:18.649 align:start position:0% then uh a kidney cannot actually call the<01:14:16.860> Paul<01:14:17.040> functions<01:14:17.580> uh<01:14:18.120> automatically 01:14:18.649 --> 01:14:18.659 align:start position:0% the Paul functions uh automatically 01:14:18.659 --> 01:14:20.390 align:start position:0% the Paul functions uh automatically because<01:14:18.900> it<01:14:19.140> has<01:14:19.500> everything<01:14:19.679> but<01:14:20.100> in<01:14:20.280> this 01:14:20.390 --> 01:14:20.400 align:start position:0% because it has everything but in this 01:14:20.400 --> 01:14:22.669 align:start position:0% because it has everything but in this case<01:14:20.520> we're<01:14:20.820> going<01:14:21.000> to<01:14:21.120> go<01:14:21.300> into<01:14:21.480> simple<01:14:21.780> route 01:14:22.669 --> 01:14:22.679 align:start position:0% case we're going to go into simple route 01:14:22.679 --> 01:14:25.910 align:start position:0% case we're going to go into simple route uh<01:14:23.219> that<01:14:23.520> is<01:14:23.640> going<01:14:23.880> to<01:14:24.060> uh<01:14:24.780> take<01:14:25.080> us<01:14:25.260> to<01:14:25.560> uh 01:14:25.910 --> 01:14:25.920 align:start position:0% uh that is going to uh take us to uh 01:14:25.920 --> 01:14:28.370 align:start position:0% uh that is going to uh take us to uh rewrite<01:14:26.400> it's<01:14:26.820> just<01:14:27.120> a<01:14:27.300> couple<01:14:27.420> of<01:14:27.600> and<01:14:28.140> this 01:14:28.370 --> 01:14:28.380 align:start position:0% rewrite it's just a couple of and this 01:14:28.380 --> 01:14:29.990 align:start position:0% rewrite it's just a couple of and this kind<01:14:28.620> of<01:14:28.739> much<01:14:28.980> what<01:14:29.340> we're<01:14:29.400> doing<01:14:29.640> here<01:14:29.820> in 01:14:29.990 --> 01:14:30.000 align:start position:0% kind of much what we're doing here in 01:14:30.000 --> 01:14:32.149 align:start position:0% kind of much what we're doing here in order<01:14:30.179> we<01:14:30.900> might<01:14:31.020> look<01:14:31.199> at<01:14:31.440> the<01:14:31.739> existing 01:14:32.149 --> 01:14:32.159 align:start position:0% order we might look at the existing 01:14:32.159 --> 01:14:33.290 align:start position:0% order we might look at the existing unique<01:14:32.520> tests<01:14:32.760> to<01:14:32.880> understand<01:14:33.000> the 01:14:33.290 --> 01:14:33.300 align:start position:0% unique tests to understand the 01:14:33.300 --> 01:14:35.090 align:start position:0% unique tests to understand the initialization<01:14:33.900> and<01:14:34.560> we<01:14:34.739> might<01:14:34.860> translate 01:14:35.090 --> 01:14:35.100 align:start position:0% initialization and we might translate 01:14:35.100 --> 01:14:37.550 align:start position:0% initialization and we might translate them<01:14:35.460> into<01:14:35.640> solidity<01:14:36.060> if<01:14:36.179> needed<01:14:36.600> to<01:14:37.199> assign 01:14:37.550 --> 01:14:37.560 align:start position:0% them into solidity if needed to assign 01:14:37.560 --> 01:14:47.390 align:start position:0% them into solidity if needed to assign credit<01:14:37.800> for<01:14:38.100> the<01:14:38.219> invariants 01:14:47.390 --> 01:14:47.400 align:start position:0% 01:14:47.400 --> 01:14:49.669 align:start position:0% so<01:14:47.760> yeah<01:14:47.820> the<01:14:48.060> the<01:14:48.239> previous<01:14:48.719> exercises<01:14:49.199> are 01:14:49.669 --> 01:14:49.679 align:start position:0% so yeah the the previous exercises are 01:14:49.679 --> 01:14:52.130 align:start position:0% so yeah the the previous exercises are on<01:14:50.340> the<01:14:50.460> easy<01:14:50.580> side<01:14:50.940> this<01:14:51.239> is<01:14:51.360> a<01:14:51.600> bit<01:14:51.840> more 01:14:52.130 --> 01:14:52.140 align:start position:0% on the easy side this is a bit more 01:14:52.140 --> 01:14:53.870 align:start position:0% on the easy side this is a bit more difficult<01:14:52.440> but<01:14:52.860> still<01:14:53.040> shouldn't<01:14:53.699> require 01:14:53.870 --> 01:14:53.880 align:start position:0% difficult but still shouldn't require 01:14:53.880 --> 01:14:56.149 align:start position:0% difficult but still shouldn't require more<01:14:54.179> than<01:14:54.300> a<01:14:54.480> few<01:14:54.600> lines 01:14:56.149 --> 01:14:56.159 align:start position:0% more than a few lines 01:14:56.159 --> 01:14:56.870 align:start position:0% more than a few lines um 01:14:56.870 --> 01:14:56.880 align:start position:0% um 01:14:56.880 --> 01:15:00.470 align:start position:0% um so<01:14:57.480> yeah<01:14:58.040> but<01:14:59.040> please<01:14:59.219> let<01:14:59.520> us<01:14:59.640> know<01:14:59.760> if<01:15:00.060> you<01:15:00.179> if 01:15:00.470 --> 01:15:00.480 align:start position:0% so yeah but please let us know if you if 01:15:00.480 --> 01:15:03.169 align:start position:0% so yeah but please let us know if you if you<01:15:00.780> need<01:15:00.900> some<01:15:01.260> some<01:15:01.920> hints<01:15:02.580> there<01:15:02.820> are<01:15:02.940> some 01:15:03.169 --> 01:15:03.179 align:start position:0% you need some some hints there are some 01:15:03.179 --> 01:15:05.630 align:start position:0% you need some some hints there are some hints<01:15:03.719> in<01:15:04.500> um 01:15:05.630 --> 01:15:05.640 align:start position:0% hints in um 01:15:05.640 --> 01:15:08.090 align:start position:0% hints in um in<01:15:05.699> one<01:15:06.480> of<01:15:06.540> the<01:15:06.780> one<01:15:07.199> of<01:15:07.260> the<01:15:07.380> branches<01:15:07.800> in<01:15:07.980> the 01:15:08.090 --> 01:15:08.100 align:start position:0% in one of the one of the branches in the 01:15:08.100 --> 01:15:11.510 align:start position:0% in one of the one of the branches in the hint<01:15:08.280> Branch<01:15:08.699> but<01:15:09.060> yeah<01:15:09.300> Heather<01:15:10.260> uh<01:15:11.219> hello 01:15:11.510 --> 01:15:11.520 align:start position:0% hint Branch but yeah Heather uh hello 01:15:11.520 --> 01:15:14.090 align:start position:0% hint Branch but yeah Heather uh hello yeah<01:15:12.480> sorry<01:15:12.780> no<01:15:13.199> worries 01:15:14.090 --> 01:15:14.100 align:start position:0% yeah sorry no worries 01:15:14.100 --> 01:15:16.669 align:start position:0% yeah sorry no worries um<01:15:14.159> is<01:15:14.460> there<01:15:14.640> any<01:15:14.820> thought<01:15:15.239> or<01:15:15.840> current 01:15:16.669 --> 01:15:16.679 align:start position:0% um is there any thought or current 01:15:16.679 --> 01:15:19.910 align:start position:0% um is there any thought or current support<01:15:16.980> for<01:15:17.400> mainnet<01:15:18.000> forking<01:15:18.480> or 01:15:19.910 --> 01:15:19.920 align:start position:0% support for mainnet forking or 01:15:19.920 --> 01:15:22.030 align:start position:0% support for mainnet forking or um State<01:15:20.280> forking<01:15:20.760> of<01:15:20.940> some<01:15:21.120> sort 01:15:22.030 --> 01:15:22.040 align:start position:0% um State forking of some sort 01:15:22.040 --> 01:15:26.870 align:start position:0% um State forking of some sort not<01:15:23.040> yet<01:15:23.219> yes<01:15:24.179> so<01:15:24.659> not<01:15:25.440> yet<01:15:25.620> havm<01:15:26.340> has<01:15:26.580> support 01:15:26.870 --> 01:15:26.880 align:start position:0% not yet yes so not yet havm has support 01:15:26.880 --> 01:15:30.709 align:start position:0% not yet yes so not yet havm has support for<01:15:27.540> that<01:15:28.500> but<01:15:28.980> that<01:15:29.159> will<01:15:29.460> that<01:15:29.940> will<01:15:30.239> need<01:15:30.420> us 01:15:30.709 --> 01:15:30.719 align:start position:0% for that but that will that will need us 01:15:30.719 --> 01:15:34.669 align:start position:0% for that but that will that will need us to<01:15:31.020> put<01:15:31.340> uh<01:15:32.340> that<01:15:32.940> requires<01:15:33.360> to<01:15:33.480> do<01:15:33.659> like<01:15:33.960> input 01:15:34.669 --> 01:15:34.679 align:start position:0% to put uh that requires to do like input 01:15:34.679 --> 01:15:38.149 align:start position:0% to put uh that requires to do like input outputs<01:15:35.219> on<01:15:35.940> on<01:15:36.120> transactions<01:15:36.719> so<01:15:36.900> we<01:15:37.800> need<01:15:37.980> to 01:15:38.149 --> 01:15:38.159 align:start position:0% outputs on on transactions so we need to 01:15:38.159 --> 01:15:42.169 align:start position:0% outputs on on transactions so we need to check<01:15:38.460> if<01:15:38.820> that<01:15:39.179> will<01:15:39.360> impact<01:15:39.780> on<01:15:40.320> the<01:15:40.620> actual 01:15:42.169 --> 01:15:42.179 align:start position:0% check if that will impact on the actual 01:15:42.179 --> 01:15:43.790 align:start position:0% check if that will impact on the actual um<01:15:42.300> on<01:15:42.659> the<01:15:42.780> actual 01:15:43.790 --> 01:15:43.800 align:start position:0% um on the actual 01:15:43.800 --> 01:15:47.030 align:start position:0% um on the actual um<01:15:43.920> performance<01:15:44.760> on<01:15:45.300> the<01:15:45.420> call 01:15:47.030 --> 01:15:47.040 align:start position:0% um performance on the call 01:15:47.040 --> 01:15:48.890 align:start position:0% um performance on the call um so<01:15:47.460> yeah<01:15:47.580> that<01:15:48.060> will 01:15:48.890 --> 01:15:48.900 align:start position:0% um so yeah that will 01:15:48.900 --> 01:15:50.149 align:start position:0% um so yeah that will um 01:15:50.149 --> 01:15:50.159 align:start position:0% um 01:15:50.159 --> 01:15:51.890 align:start position:0% um yeah 01:15:51.890 --> 01:15:51.900 align:start position:0% yeah 01:15:51.900 --> 01:15:54.890 align:start position:0% yeah um<01:15:51.960> I<01:15:52.260> have<01:15:52.380> kind<01:15:52.739> of<01:15:52.920> high<01:15:53.640> level<01:15:53.940> questions 01:15:54.890 --> 01:15:54.900 align:start position:0% um I have kind of high level questions 01:15:54.900 --> 01:15:56.930 align:start position:0% um I have kind of high level questions so<01:15:55.320> I'm<01:15:55.440> trying<01:15:55.920> to<01:15:56.100> think<01:15:56.340> about<01:15:56.460> what<01:15:56.820> the 01:15:56.930 --> 01:15:56.940 align:start position:0% so I'm trying to think about what the 01:15:56.940 --> 01:15:59.750 align:start position:0% so I'm trying to think about what the limitations<01:15:57.420> are<01:15:58.020> in<01:15:58.440> terms<01:15:58.679> of 01:15:59.750 --> 01:15:59.760 align:start position:0% limitations are in terms of 01:15:59.760 --> 01:16:01.970 align:start position:0% limitations are in terms of expressing<01:16:00.600> properties<01:16:01.080> as<01:16:01.320> invariance 01:16:01.970 --> 01:16:01.980 align:start position:0% expressing properties as invariance 01:16:01.980 --> 01:16:04.910 align:start position:0% expressing properties as invariance right<01:16:02.460> so<01:16:02.760> for<01:16:03.000> example<01:16:03.300> let's<01:16:04.140> say<01:16:04.260> we<01:16:04.560> have<01:16:04.679> a 01:16:04.910 --> 01:16:04.920 align:start position:0% right so for example let's say we have a 01:16:04.920 --> 01:16:06.709 align:start position:0% right so for example let's say we have a temporal<01:16:05.400> property<01:16:05.880> that<01:16:06.300> we<01:16:06.480> want<01:16:06.600> to 01:16:06.709 --> 01:16:06.719 align:start position:0% temporal property that we want to 01:16:06.719 --> 01:16:09.410 align:start position:0% temporal property that we want to express<01:16:06.900> like<01:16:07.560> we<01:16:08.340> have<01:16:08.460> a<01:16:08.580> wallet<01:16:08.940> contract 01:16:09.410 --> 01:16:09.420 align:start position:0% express like we have a wallet contract 01:16:09.420 --> 01:16:11.570 align:start position:0% express like we have a wallet contract and<01:16:09.960> we<01:16:10.140> want<01:16:10.260> to<01:16:10.380> be<01:16:10.500> able<01:16:10.620> to<01:16:10.800> say<01:16:10.980> that<01:16:11.340> any 01:16:11.570 --> 01:16:11.580 align:start position:0% and we want to be able to say that any 01:16:11.580 --> 01:16:14.270 align:start position:0% and we want to be able to say that any user<01:16:12.060> who<01:16:12.780> deposits<01:16:13.380> their<01:16:13.560> money<01:16:13.800> is 01:16:14.270 --> 01:16:14.280 align:start position:0% user who deposits their money is 01:16:14.280 --> 01:16:16.550 align:start position:0% user who deposits their money is eventually<01:16:14.699> able<01:16:15.239> to<01:16:15.360> withdraw<01:16:15.840> it<01:16:16.080> is<01:16:16.380> that 01:16:16.550 --> 01:16:16.560 align:start position:0% eventually able to withdraw it is that 01:16:16.560 --> 01:16:18.649 align:start position:0% eventually able to withdraw it is that just<01:16:16.739> like<01:16:16.980> a<01:16:17.280> fundamental<01:16:17.820> limitation<01:16:18.239> of 01:16:18.649 --> 01:16:18.659 align:start position:0% just like a fundamental limitation of 01:16:18.659 --> 01:16:21.169 align:start position:0% just like a fundamental limitation of Echidna<01:16:19.199> or<01:16:19.380> is<01:16:19.500> there<01:16:19.679> a<01:16:19.860> way<01:16:19.980> to<01:16:20.159> so<01:16:20.760> if<01:16:21.060> you 01:16:21.169 --> 01:16:21.179 align:start position:0% Echidna or is there a way to so if you 01:16:21.179 --> 01:16:22.490 align:start position:0% Echidna or is there a way to so if you can 01:16:22.490 --> 01:16:22.500 align:start position:0% can 01:16:22.500 --> 01:16:26.450 align:start position:0% can so<01:16:23.280> the<01:16:24.239> notion<01:16:24.480> of<01:16:24.659> eventually<01:16:25.140> it's<01:16:25.980> you<01:16:26.340> you 01:16:26.450 --> 01:16:26.460 align:start position:0% so the notion of eventually it's you you 01:16:26.460 --> 01:16:28.490 align:start position:0% so the notion of eventually it's you you need<01:16:26.820> to<01:16:26.940> have<01:16:27.060> some<01:16:27.239> definition<01:16:27.360> on<01:16:27.900> the<01:16:28.140> or 01:16:28.490 --> 01:16:28.500 align:start position:0% need to have some definition on the or 01:16:28.500 --> 01:16:30.950 align:start position:0% need to have some definition on the or on<01:16:28.800> the<01:16:29.100> blockchain<01:16:29.460> right<01:16:29.880> So<01:16:30.480> eventually 01:16:30.950 --> 01:16:30.960 align:start position:0% on the blockchain right So eventually 01:16:30.960 --> 01:16:34.250 align:start position:0% on the blockchain right So eventually cannot<01:16:31.620> mean<01:16:32.100> like<01:16:32.400> in<01:16:32.520> 100<01:16:32.640> years<01:16:33.060> right<01:16:33.960> so 01:16:34.250 --> 01:16:34.260 align:start position:0% cannot mean like in 100 years right so 01:16:34.260 --> 01:16:38.090 align:start position:0% cannot mean like in 100 years right so if<01:16:34.440> you<01:16:34.560> if<01:16:34.980> you<01:16:35.280> find<01:16:35.880> say<01:16:36.179> I<01:16:36.840> will<01:16:37.020> only<01:16:37.620> allow 01:16:38.090 --> 01:16:38.100 align:start position:0% if you if you find say I will only allow 01:16:38.100 --> 01:16:41.330 align:start position:0% if you if you find say I will only allow increment<01:16:38.760> of<01:16:39.000> time<01:16:39.300> up<01:16:39.719> to<01:16:39.900> some<01:16:40.080> limit<01:16:40.340> yes 01:16:41.330 --> 01:16:41.340 align:start position:0% increment of time up to some limit yes 01:16:41.340 --> 01:16:45.070 align:start position:0% increment of time up to some limit yes you<01:16:41.820> can<01:16:41.940> you<01:16:42.600> can<01:16:42.780> call<01:16:42.960> it<01:16:43.199> as<01:16:43.380> a<01:16:44.000> bounded 01:16:45.070 --> 01:16:45.080 align:start position:0% you can you can call it as a bounded 01:16:45.080 --> 01:16:49.130 align:start position:0% you can you can call it as a bounded version<01:16:46.080> of<01:16:46.679> that<01:16:46.860> property<01:16:47.280> but<01:16:48.120> you<01:16:48.780> cannot 01:16:49.130 --> 01:16:49.140 align:start position:0% version of that property but you cannot 01:16:49.140 --> 01:16:52.550 align:start position:0% version of that property but you cannot you<01:16:49.800> cannot<01:16:50.159> use<01:16:50.580> it<01:16:50.760> as<01:16:50.940> a<01:16:51.179> theoretical<01:16:52.020> thing 01:16:52.550 --> 01:16:52.560 align:start position:0% you cannot use it as a theoretical thing 01:16:52.560 --> 01:16:55.669 align:start position:0% you cannot use it as a theoretical thing like<01:16:52.920> you<01:16:53.460> know<01:16:53.520> I<01:16:53.760> have<01:16:53.940> a<01:16:54.179> state<01:16:54.480> which<01:16:55.320> I 01:16:55.669 --> 01:16:55.679 align:start position:0% like you know I have a state which I 01:16:55.679 --> 01:16:57.470 align:start position:0% like you know I have a state which I don't<01:16:55.739> know<01:16:55.920> what<01:16:56.100> it<01:16:56.280> is<01:16:56.400> and<01:16:56.880> then<01:16:57.060> I<01:16:57.239> will 01:16:57.470 --> 01:16:57.480 align:start position:0% don't know what it is and then I will 01:16:57.480 --> 01:16:59.810 align:start position:0% don't know what it is and then I will transition<01:16:57.900> to<01:16:58.140> another<01:16:58.260> state<01:16:58.679> which<01:16:59.580> I 01:16:59.810 --> 01:16:59.820 align:start position:0% transition to another state which I 01:16:59.820 --> 01:17:03.050 align:start position:0% transition to another state which I don't<01:16:59.880> know<01:17:00.060> which<01:17:00.300> uh<01:17:01.080> what<01:17:01.620> it<01:17:01.739> is<01:17:01.860> and<01:17:02.699> in 01:17:03.050 --> 01:17:03.060 align:start position:0% don't know which uh what it is and in 01:17:03.060 --> 01:17:05.510 align:start position:0% don't know which uh what it is and in that<01:17:03.239> case<01:17:03.480> you<01:17:03.960> will<01:17:04.080> need<01:17:04.320> to<01:17:04.560> know<01:17:04.800> if<01:17:05.340> the 01:17:05.510 --> 01:17:05.520 align:start position:0% that case you will need to know if the 01:17:05.520 --> 01:17:09.229 align:start position:0% that case you will need to know if the original<01:17:05.640> state<01:17:06.360> was<01:17:07.020> actually<01:17:07.320> possible<01:17:08.239> and 01:17:09.229 --> 01:17:09.239 align:start position:0% original state was actually possible and 01:17:09.239 --> 01:17:12.830 align:start position:0% original state was actually possible and and<01:17:09.659> things<01:17:10.140> like<01:17:10.320> that<01:17:10.440> so<01:17:11.239> it<01:17:12.239> kind<01:17:12.360> of<01:17:12.540> works 01:17:12.830 --> 01:17:12.840 align:start position:0% and things like that so it kind of works 01:17:12.840 --> 01:17:16.370 align:start position:0% and things like that so it kind of works on<01:17:12.900> on<01:17:13.620> a<01:17:13.860> concrete<01:17:14.340> on<01:17:15.179> on<01:17:15.420> concrete<01:17:15.960> States 01:17:16.370 --> 01:17:16.380 align:start position:0% on on a concrete on on concrete States 01:17:16.380 --> 01:17:19.610 align:start position:0% on on a concrete on on concrete States so<01:17:17.280> you<01:17:17.580> always<01:17:17.699> have<01:17:18.080> concrete<01:17:19.080> data<01:17:19.380> and<01:17:19.500> you 01:17:19.610 --> 01:17:19.620 align:start position:0% so you always have concrete data and you 01:17:19.620 --> 01:17:21.169 align:start position:0% so you always have concrete data and you need<01:17:19.739> to<01:17:19.860> put<01:17:19.980> like<01:17:20.280> boundaries<01:17:20.820> on<01:17:21.000> the 01:17:21.169 --> 01:17:21.179 align:start position:0% need to put like boundaries on the 01:17:21.179 --> 01:17:23.270 align:start position:0% need to put like boundaries on the things<01:17:21.360> that<01:17:21.659> you<01:17:21.840> that<01:17:22.080> you<01:17:22.260> can<01:17:22.320> do<01:17:22.560> so<01:17:23.100> if 01:17:23.270 --> 01:17:23.280 align:start position:0% things that you that you can do so if 01:17:23.280 --> 01:17:27.649 align:start position:0% things that you that you can do so if you<01:17:23.460> say<01:17:23.760> a<01:17:24.300> user<01:17:24.840> should<01:17:25.340> eventually<01:17:26.659> uh 01:17:27.649 --> 01:17:27.659 align:start position:0% you say a user should eventually uh 01:17:27.659 --> 01:17:30.770 align:start position:0% you say a user should eventually uh receive<01:17:28.199> this<01:17:28.739> amount<01:17:29.100> and<01:17:29.940> eventually<01:17:30.360> means 01:17:30.770 --> 01:17:30.780 align:start position:0% receive this amount and eventually means 01:17:30.780 --> 01:17:32.450 align:start position:0% receive this amount and eventually means like<01:17:31.020> in<01:17:31.320> a<01:17:31.500> number<01:17:31.560> of<01:17:31.679> transactions<01:17:32.159> and<01:17:32.340> a 01:17:32.450 --> 01:17:32.460 align:start position:0% like in a number of transactions and a 01:17:32.460 --> 01:17:34.810 align:start position:0% like in a number of transactions and a number<01:17:32.580> of<01:17:32.699> blocks<01:17:33.179> or<01:17:33.239> timestamp<01:17:33.780> then<01:17:34.500> yes 01:17:34.810 --> 01:17:34.820 align:start position:0% number of blocks or timestamp then yes 01:17:34.820 --> 01:17:37.430 align:start position:0% number of blocks or timestamp then yes otherwise<01:17:35.820> it's<01:17:36.659> it's<01:17:36.840> more<01:17:37.080> like<01:17:37.260> a 01:17:37.430 --> 01:17:37.440 align:start position:0% otherwise it's it's more like a 01:17:37.440 --> 01:17:39.830 align:start position:0% otherwise it's it's more like a theoretical<01:17:38.000> proof<01:17:39.000> that<01:17:39.179> you're<01:17:39.300> doing<01:17:39.540> and 01:17:39.830 --> 01:17:39.840 align:start position:0% theoretical proof that you're doing and 01:17:39.840 --> 01:17:41.450 align:start position:0% theoretical proof that you're doing and you<01:17:40.199> probably<01:17:40.380> need<01:17:40.620> another<01:17:40.739> type<01:17:41.040> of<01:17:41.159> tool 01:17:41.450 --> 01:17:41.460 align:start position:0% you probably need another type of tool 01:17:41.460 --> 01:17:43.850 align:start position:0% you probably need another type of tool yeah<01:17:42.120> I<01:17:42.300> guess<01:17:42.480> I'm<01:17:43.020> curious<01:17:43.320> even<01:17:43.560> if<01:17:43.739> you 01:17:43.850 --> 01:17:43.860 align:start position:0% yeah I guess I'm curious even if you 01:17:43.860 --> 01:17:45.290 align:start position:0% yeah I guess I'm curious even if you took<01:17:44.040> like<01:17:44.219> the<01:17:44.460> bounded<01:17:44.940> case<01:17:45.060> because 01:17:45.290 --> 01:17:45.300 align:start position:0% took like the bounded case because 01:17:45.300 --> 01:17:46.669 align:start position:0% took like the bounded case because that's<01:17:45.480> fair<01:17:45.719> that<01:17:46.020> you're<01:17:46.199> dealing<01:17:46.560> with 01:17:46.669 --> 01:17:46.679 align:start position:0% that's fair that you're dealing with 01:17:46.679 --> 01:17:48.770 align:start position:0% that's fair that you're dealing with like<01:17:46.860> concrete<01:17:47.280> traces<01:17:47.699> here<01:17:47.880> it<01:17:48.420> seems<01:17:48.659> like 01:17:48.770 --> 01:17:48.780 align:start position:0% like concrete traces here it seems like 01:17:48.780 --> 01:17:50.630 align:start position:0% like concrete traces here it seems like that's<01:17:49.020> not<01:17:49.320> or<01:17:49.679> it's<01:17:49.800> not<01:17:49.980> intuitive<01:17:50.340> to<01:17:50.580> me 01:17:50.630 --> 01:17:50.640 align:start position:0% that's not or it's not intuitive to me 01:17:50.640 --> 01:17:52.189 align:start position:0% that's not or it's not intuitive to me anyway<01:17:50.820> how<01:17:51.120> you<01:17:51.300> would<01:17:51.420> Express<01:17:51.600> that<01:17:51.960> as 01:17:52.189 --> 01:17:52.199 align:start position:0% anyway how you would Express that as 01:17:52.199 --> 01:17:54.169 align:start position:0% anyway how you would Express that as like<01:17:52.500> one<01:17:52.739> of<01:17:52.860> these<01:17:53.040> invariants<01:17:53.520> so<01:17:53.880> you<01:17:54.060> you 01:17:54.169 --> 01:17:54.179 align:start position:0% like one of these invariants so you you 01:17:54.179 --> 01:17:56.810 align:start position:0% like one of these invariants so you you will<01:17:54.360> you<01:17:55.020> will<01:17:55.199> do<01:17:55.380> something<01:17:55.620> like<01:17:55.980> this<01:17:56.159> you 01:17:56.810 --> 01:17:56.820 align:start position:0% will you will do something like this you 01:17:56.820 --> 01:18:01.010 align:start position:0% will you will do something like this you will<01:17:57.000> put<01:17:57.300> a<01:17:57.719> function<01:17:58.260> that<01:17:58.920> says<01:17:59.300> uh<01:18:00.300> and<01:18:00.719> and 01:18:01.010 --> 01:18:01.020 align:start position:0% will put a function that says uh and and 01:18:01.020 --> 01:18:02.870 align:start position:0% will put a function that says uh and and you<01:18:01.440> will<01:18:01.500> need<01:18:01.739> a 01:18:02.870 --> 01:18:02.880 align:start position:0% you will need a 01:18:02.880 --> 01:18:06.410 align:start position:0% you will need a state<01:18:03.719> to<01:18:04.020> track<01:18:04.260> down<01:18:04.560> like<01:18:04.920> uh<01:18:05.640> you<01:18:05.880> you<01:18:06.120> do<01:18:06.300> a 01:18:06.410 --> 01:18:06.420 align:start position:0% state to track down like uh you you do a 01:18:06.420 --> 01:18:08.810 align:start position:0% state to track down like uh you you do a deposit<01:18:06.900> and<01:18:07.739> you<01:18:07.920> will<01:18:08.040> need<01:18:08.219> a<01:18:08.400> user<01:18:08.699> to 01:18:08.810 --> 01:18:08.820 align:start position:0% deposit and you will need a user to 01:18:08.820 --> 01:18:11.090 align:start position:0% deposit and you will need a user to eventually<01:18:09.120> receive<01:18:09.659> something<01:18:09.900> right<01:18:10.380> so 01:18:11.090 --> 01:18:11.100 align:start position:0% eventually receive something right so 01:18:11.100 --> 01:18:12.890 align:start position:0% eventually receive something right so you<01:18:11.460> will<01:18:11.640> need<01:18:11.820> to<01:18:12.060> have<01:18:12.239> a<01:18:12.420> state<01:18:12.600> that 01:18:12.890 --> 01:18:12.900 align:start position:0% you will need to have a state that 01:18:12.900 --> 01:18:16.370 align:start position:0% you will need to have a state that tracks<01:18:13.440> deposit<01:18:13.980> like<01:18:14.159> a<01:18:14.400> mapping<01:18:14.760> right<01:18:15.600> and 01:18:16.370 --> 01:18:16.380 align:start position:0% tracks deposit like a mapping right and 01:18:16.380 --> 01:18:18.169 align:start position:0% tracks deposit like a mapping right and you<01:18:16.620> have<01:18:16.739> a<01:18:16.920> function<01:18:17.159> that<01:18:17.580> is<01:18:17.940> your 01:18:18.169 --> 01:18:18.179 align:start position:0% you have a function that is your 01:18:18.179 --> 01:18:20.990 align:start position:0% you have a function that is your invariant<01:18:18.719> so<01:18:19.560> if 01:18:20.990 --> 01:18:21.000 align:start position:0% invariant so if 01:18:21.000 --> 01:18:23.689 align:start position:0% invariant so if um<01:18:21.060> and<01:18:21.719> then<01:18:21.960> you<01:18:22.140> receive<01:18:22.560> the<01:18:23.159> address<01:18:23.280> of<01:18:23.580> a 01:18:23.689 --> 01:18:23.699 align:start position:0% um and then you receive the address of a 01:18:23.699 --> 01:18:26.930 align:start position:0% um and then you receive the address of a user<01:18:24.000> and<01:18:24.540> you<01:18:24.659> check<01:18:24.840> in<01:18:25.020> the<01:18:25.140> mapping<01:18:25.520> uh<01:18:26.520> if 01:18:26.930 --> 01:18:26.940 align:start position:0% user and you check in the mapping uh if 01:18:26.940 --> 01:18:29.149 align:start position:0% user and you check in the mapping uh if if<01:18:27.360> the<01:18:27.840> time 01:18:29.149 --> 01:18:29.159 align:start position:0% if the time 01:18:29.159 --> 01:18:32.510 align:start position:0% if the time um<01:18:29.219> between<01:18:29.760> the<01:18:30.300> last<01:18:30.540> deposit<01:18:31.199> is<01:18:31.980> in<01:18:32.400> this 01:18:32.510 --> 01:18:32.520 align:start position:0% um between the last deposit is in this 01:18:32.520 --> 01:18:34.250 align:start position:0% um between the last deposit is in this range<01:18:32.940> then<01:18:33.480> you<01:18:33.659> were<01:18:33.840> going<01:18:33.960> to<01:18:34.080> check 01:18:34.250 --> 01:18:34.260 align:start position:0% range then you were going to check 01:18:34.260 --> 01:18:36.830 align:start position:0% range then you were going to check something<01:18:34.560> and<01:18:35.280> if<01:18:35.460> if<01:18:35.699> the<01:18:36.060> time<01:18:36.239> in<01:18:36.420> this<01:18:36.600> in 01:18:36.830 --> 01:18:36.840 align:start position:0% something and if if the time in this in 01:18:36.840 --> 01:18:38.030 align:start position:0% something and if if the time in this in this<01:18:36.960> other<01:18:37.140> range<01:18:37.440> you're<01:18:37.620> going<01:18:37.800> to<01:18:37.920> check 01:18:38.030 --> 01:18:38.040 align:start position:0% this other range you're going to check 01:18:38.040 --> 01:18:40.189 align:start position:0% this other range you're going to check some<01:18:38.280> something<01:18:38.580> else<01:18:38.880> so<01:18:39.480> it<01:18:39.600> will<01:18:39.780> be<01:18:39.960> like 01:18:40.189 --> 01:18:40.199 align:start position:0% some something else so it will be like 01:18:40.199 --> 01:18:44.149 align:start position:0% some something else so it will be like randomly<01:18:40.920> checking<01:18:41.520> in<01:18:41.880> in<01:18:42.239> transactions 01:18:44.149 --> 01:18:44.159 align:start position:0% randomly checking in in transactions 01:18:44.159 --> 01:18:46.610 align:start position:0% randomly checking in in transactions um<01:18:44.219> and<01:18:44.880> with<01:18:45.360> that<01:18:45.540> you<01:18:46.020> will<01:18:46.199> be<01:18:46.320> able<01:18:46.440> to 01:18:46.610 --> 01:18:46.620 align:start position:0% um and with that you will be able to 01:18:46.620 --> 01:18:47.530 align:start position:0% um and with that you will be able to cover 01:18:47.530 --> 01:18:47.540 align:start position:0% cover 01:18:47.540 --> 01:18:50.810 align:start position:0% cover uh<01:18:48.540> given<01:18:49.380> the<01:18:49.560> fact<01:18:49.739> that<01:18:50.100> you're<01:18:50.400> going<01:18:50.699> to 01:18:50.810 --> 01:18:50.820 align:start position:0% uh given the fact that you're going to 01:18:50.820 --> 01:18:52.610 align:start position:0% uh given the fact that you're going to generate<01:18:51.239> enough<01:18:51.420> transactions<01:18:52.140> and<01:18:52.380> enough 01:18:52.610 --> 01:18:52.620 align:start position:0% generate enough transactions and enough 01:18:52.620 --> 01:18:54.770 align:start position:0% generate enough transactions and enough time<01:18:52.980> times<01:18:53.219> right<01:18:53.640> so<01:18:54.120> it<01:18:54.300> seems<01:18:54.540> like<01:18:54.600> the 01:18:54.770 --> 01:18:54.780 align:start position:0% time times right so it seems like the 01:18:54.780 --> 01:18:56.930 align:start position:0% time times right so it seems like the answer<01:18:54.960> is<01:18:55.199> it's<01:18:55.620> capable<01:18:56.219> of<01:18:56.400> doing<01:18:56.580> it<01:18:56.760> but 01:18:56.930 --> 01:18:56.940 align:start position:0% answer is it's capable of doing it but 01:18:56.940 --> 01:18:58.669 align:start position:0% answer is it's capable of doing it but it<01:18:57.120> requires<01:18:57.540> some<01:18:57.780> like<01:18:57.960> kind<01:18:58.140> of<01:18:58.260> manual 01:18:58.669 --> 01:18:58.679 align:start position:0% it requires some like kind of manual 01:18:58.679 --> 01:19:00.470 align:start position:0% it requires some like kind of manual adjustment<01:18:59.280> of<01:18:59.460> the<01:18:59.580> code<01:18:59.699> almost<01:18:59.940> to<01:19:00.300> add 01:19:00.470 --> 01:19:00.480 align:start position:0% adjustment of the code almost to add 01:19:00.480 --> 01:19:03.470 align:start position:0% adjustment of the code almost to add state<01:19:00.780> of<01:19:00.900> it<01:19:01.140> so<01:19:01.320> yeah<01:19:01.500> you<01:19:01.679> will<01:19:01.860> you<01:19:02.159> so<01:19:02.820> if 01:19:03.470 --> 01:19:03.480 align:start position:0% state of it so yeah you will you so if 01:19:03.480 --> 01:19:05.630 align:start position:0% state of it so yeah you will you so if the<01:19:03.719> if<01:19:04.260> the<01:19:04.500> property<01:19:04.800> that<01:19:04.920> you<01:19:05.100> are<01:19:05.280> testing 01:19:05.630 --> 01:19:05.640 align:start position:0% the if the property that you are testing 01:19:05.640 --> 01:19:09.290 align:start position:0% the if the property that you are testing requires<01:19:06.540> to<01:19:07.260> add<01:19:07.620> State<01:19:07.980> yes<01:19:08.400> you<01:19:08.880> will<01:19:09.060> need 01:19:09.290 --> 01:19:09.300 align:start position:0% requires to add State yes you will need 01:19:09.300 --> 01:19:12.470 align:start position:0% requires to add State yes you will need to<01:19:09.420> add<01:19:09.719> whatever<01:19:10.380> state<01:19:10.920> is<01:19:11.460> needed<01:19:11.880> it<01:19:12.300> won't 01:19:12.470 --> 01:19:12.480 align:start position:0% to add whatever state is needed it won't 01:19:12.480 --> 01:19:14.930 align:start position:0% to add whatever state is needed it won't be<01:19:12.600> able<01:19:12.780> to<01:19:12.960> track<01:19:13.199> state<01:19:13.560> outside 01:19:14.930 --> 01:19:14.940 align:start position:0% be able to track state outside 01:19:14.940 --> 01:19:16.729 align:start position:0% be able to track state outside right<01:19:15.179> the<01:19:15.659> only<01:19:15.719> thing<01:19:15.960> that<01:19:16.140> will<01:19:16.380> be 01:19:16.729 --> 01:19:16.739 align:start position:0% right the only thing that will be 01:19:16.739 --> 01:19:20.090 align:start position:0% right the only thing that will be tracked<01:19:17.159> outside<01:19:17.400> is<01:19:18.199> the<01:19:19.199> increment<01:19:19.620> between 01:19:20.090 --> 01:19:20.100 align:start position:0% tracked outside is the increment between 01:19:20.100 --> 01:19:24.229 align:start position:0% tracked outside is the increment between between<01:19:21.060> the<01:19:21.840> uh<01:19:22.620> different<01:19:22.920> blocks 01:19:24.229 --> 01:19:24.239 align:start position:0% between the uh different blocks 01:19:24.239 --> 01:19:26.209 align:start position:0% between the uh different blocks for<01:19:24.659> instance<01:19:24.960> so<01:19:25.500> that<01:19:25.620> that<01:19:25.860> will<01:19:26.100> be 01:19:26.209 --> 01:19:26.219 align:start position:0% for instance so that that will be 01:19:26.219 --> 01:19:28.610 align:start position:0% for instance so that that will be tracked<01:19:26.640> uh<01:19:27.120> outside<01:19:27.360> a<01:19:27.780> new<01:19:27.960> Aquino<01:19:28.380> will 01:19:28.610 --> 01:19:28.620 align:start position:0% tracked uh outside a new Aquino will 01:19:28.620 --> 01:19:30.709 align:start position:0% tracked uh outside a new Aquino will show<01:19:28.800> you<01:19:28.920> from<01:19:29.640> in<01:19:30.000> between<01:19:30.239> this 01:19:30.709 --> 01:19:30.719 align:start position:0% show you from in between this 01:19:30.719 --> 01:19:32.390 align:start position:0% show you from in between this transactions<01:19:31.260> and<01:19:31.440> this<01:19:31.560> transaction<01:19:31.920> I<01:19:32.280> have 01:19:32.390 --> 01:19:32.400 align:start position:0% transactions and this transaction I have 01:19:32.400 --> 01:19:34.669 align:start position:0% transactions and this transaction I have 10<01:19:32.699> blocks<01:19:33.179> that<01:19:33.600> will<01:19:33.780> be<01:19:33.960> tracked<01:19:34.320> uh 01:19:34.669 --> 01:19:34.679 align:start position:0% 10 blocks that will be tracked uh 01:19:34.679 --> 01:19:36.649 align:start position:0% 10 blocks that will be tracked uh outside<01:19:34.920> but<01:19:35.280> everything<01:19:35.520> else<01:19:35.880> if<01:19:36.420> you<01:19:36.540> need 01:19:36.649 --> 01:19:36.659 align:start position:0% outside but everything else if you need 01:19:36.659 --> 01:19:39.410 align:start position:0% outside but everything else if you need to<01:19:36.780> do<01:19:36.900> a<01:19:37.080> mapping<01:19:37.440> between<01:19:38.040> users<01:19:38.699> and<01:19:39.000> and 01:19:39.410 --> 01:19:39.420 align:start position:0% to do a mapping between users and and 01:19:39.420 --> 01:19:41.090 align:start position:0% to do a mapping between users and and the<01:19:39.719> time<01:19:39.900> between 01:19:41.090 --> 01:19:41.100 align:start position:0% the time between 01:19:41.100 --> 01:19:43.250 align:start position:0% the time between certain<01:19:41.760> operation<01:19:42.239> you<01:19:42.659> will<01:19:42.780> need<01:19:42.960> to<01:19:43.080> keep 01:19:43.250 --> 01:19:43.260 align:start position:0% certain operation you will need to keep 01:19:43.260 --> 01:19:46.430 align:start position:0% certain operation you will need to keep that<01:19:43.560> in<01:19:43.980> a<01:19:44.159> different<01:19:44.280> in<01:19:44.820> installation<01:19:45.780> in<01:19:46.020> a 01:19:46.430 --> 01:19:46.440 align:start position:0% that in a different in installation in a 01:19:46.440 --> 01:19:51.229 align:start position:0% that in a different in installation in a different<01:19:46.560> bio<01:19:46.920> I<01:19:47.760> see<01:19:47.940> great<01:19:48.239> thank<01:19:48.480> you 01:19:51.229 --> 01:19:51.239 align:start position:0% 01:19:51.239 --> 01:19:54.169 align:start position:0% all<01:19:51.719> right<01:19:51.780> so<01:19:52.460> we<01:19:53.460> have 01:19:54.169 --> 01:19:54.179 align:start position:0% all right so we have 01:19:54.179 --> 01:19:58.669 align:start position:0% all right so we have some<01:19:54.659> other<01:19:54.780> questions 01:19:58.669 --> 01:19:58.679 align:start position:0% 01:19:58.679 --> 01:20:00.169 align:start position:0% hi 01:20:00.169 --> 01:20:00.179 align:start position:0% hi 01:20:00.179 --> 01:20:02.149 align:start position:0% hi um<01:20:00.300> is<01:20:00.540> there<01:20:00.659> any<01:20:00.780> feature<01:20:01.320> that<01:20:01.500> allow<01:20:01.860> me<01:20:02.040> to 01:20:02.149 --> 01:20:02.159 align:start position:0% um is there any feature that allow me to 01:20:02.159 --> 01:20:04.370 align:start position:0% um is there any feature that allow me to guide<01:20:02.460> the<01:20:02.699> future<01:20:02.940> or<01:20:03.360> the<01:20:03.600> domain<01:20:03.840> of<01:20:04.020> values 01:20:04.370 --> 01:20:04.380 align:start position:0% guide the future or the domain of values 01:20:04.380 --> 01:20:06.470 align:start position:0% guide the future or the domain of values that<01:20:04.620> I<01:20:04.800> want<01:20:04.920> to<01:20:05.040> try 01:20:06.470 --> 01:20:06.480 align:start position:0% that I want to try 01:20:06.480 --> 01:20:10.070 align:start position:0% that I want to try um so<01:20:07.440> in<01:20:07.739> order<01:20:07.920> to<01:20:08.159> in<01:20:08.820> order<01:20:09.000> to<01:20:09.360> guide<01:20:09.719> the 01:20:10.070 --> 01:20:10.080 align:start position:0% um so in order to in order to guide the 01:20:10.080 --> 01:20:12.709 align:start position:0% um so in order to in order to guide the the<01:20:10.380> faster<01:20:10.620> into<01:20:10.920> a<01:20:11.219> particular<01:20:11.520> State<01:20:12.060> the 01:20:12.709 --> 01:20:12.719 align:start position:0% the faster into a particular State the 01:20:12.719 --> 01:20:15.830 align:start position:0% the faster into a particular State the easiest<01:20:12.960> way<01:20:13.199> to<01:20:13.380> do<01:20:13.560> it<01:20:13.679> is<01:20:14.219> to<01:20:14.460> add 01:20:15.830 --> 01:20:15.840 align:start position:0% easiest way to do it is to add 01:20:15.840 --> 01:20:18.830 align:start position:0% easiest way to do it is to add um<01:20:15.960> is<01:20:16.320> is<01:20:16.620> to<01:20:16.860> add<01:20:17.040> a<01:20:17.580> small<01:20:18.179> piece<01:20:18.540> of<01:20:18.600> code 01:20:18.830 --> 01:20:18.840 align:start position:0% um is is to add a small piece of code 01:20:18.840 --> 01:20:22.330 align:start position:0% um is is to add a small piece of code that<01:20:19.620> will<01:20:19.800> be<01:20:19.920> auxiliary<01:20:20.520> code<01:20:20.760> in<01:20:21.239> order<01:20:21.360> to 01:20:22.330 --> 01:20:22.340 align:start position:0% that will be auxiliary code in order to 01:20:22.340 --> 01:20:25.310 align:start position:0% that will be auxiliary code in order to uh<01:20:23.340> move<01:20:23.699> the<01:20:24.000> state<01:20:24.300> from<01:20:24.840> your<01:20:25.020> contract 01:20:25.310 --> 01:20:25.320 align:start position:0% uh move the state from your contract 01:20:25.320 --> 01:20:27.890 align:start position:0% uh move the state from your contract into<01:20:25.500> something<01:20:25.739> else<01:20:26.040> like<01:20:26.520> for<01:20:26.940> instance<01:20:27.179> if 01:20:27.890 --> 01:20:27.900 align:start position:0% into something else like for instance if 01:20:27.900 --> 01:20:30.709 align:start position:0% into something else like for instance if you<01:20:28.080> have<01:20:28.320> if<01:20:28.860> you<01:20:28.980> have<01:20:29.159> a<01:20:29.340> contract<01:20:29.699> uh<01:20:30.179> the 01:20:30.709 --> 01:20:30.719 align:start position:0% you have if you have a contract uh the 01:20:30.719 --> 01:20:34.130 align:start position:0% you have if you have a contract uh the protocol<01:20:31.020> that<01:20:31.260> requires<01:20:31.820> a<01:20:32.820> deposit<01:20:33.540> with<01:20:33.900> a 01:20:34.130 --> 01:20:34.140 align:start position:0% protocol that requires a deposit with a 01:20:34.140 --> 01:20:38.030 align:start position:0% protocol that requires a deposit with a particular<01:20:35.000> uh<01:20:36.000> property<01:20:36.360> let's<01:20:36.659> say<01:20:36.900> that<01:20:37.320> uh 01:20:38.030 --> 01:20:38.040 align:start position:0% particular uh property let's say that uh 01:20:38.040 --> 01:20:41.030 align:start position:0% particular uh property let's say that uh you<01:20:38.219> have<01:20:38.400> three<01:20:38.880> parameters<01:20:39.600> and<01:20:40.140> you<01:20:40.320> need<01:20:40.560> a 01:20:41.030 --> 01:20:41.040 align:start position:0% you have three parameters and you need a 01:20:41.040 --> 01:20:44.030 align:start position:0% you have three parameters and you need a deposit<01:20:41.580> that<01:20:42.300> has<01:20:42.540> uh<01:20:43.380> that<01:20:43.620> has<01:20:43.739> digital 01:20:44.030 --> 01:20:44.040 align:start position:0% deposit that has uh that has digital 01:20:44.040 --> 01:20:47.450 align:start position:0% deposit that has uh that has digital parameter<01:20:44.520> in<01:20:45.360> in<01:20:45.780> in<01:20:46.020> the<01:20:46.739> Sim<01:20:46.920> in<01:20:47.159> the<01:20:47.340> same 01:20:47.450 --> 01:20:47.460 align:start position:0% parameter in in in the Sim in the same 01:20:47.460 --> 01:20:49.550 align:start position:0% parameter in in in the Sim in the same number<01:20:47.699> or<01:20:48.000> in<01:20:48.420> numbers<01:20:48.600> in<01:20:48.900> which<01:20:49.020> in<01:20:49.260> which 01:20:49.550 --> 01:20:49.560 align:start position:0% number or in numbers in which in which 01:20:49.560 --> 01:20:51.830 align:start position:0% number or in numbers in which in which are<01:20:49.739> difficult<01:20:50.219> to<01:20:51.000> find<01:20:51.120> you<01:20:51.360> can<01:20:51.480> have<01:20:51.659> this 01:20:51.830 --> 01:20:51.840 align:start position:0% are difficult to find you can have this 01:20:51.840 --> 01:20:52.910 align:start position:0% are difficult to find you can have this piece<01:20:52.199> of<01:20:52.260> code 01:20:52.910 --> 01:20:52.920 align:start position:0% piece of code 01:20:52.920 --> 01:20:56.090 align:start position:0% piece of code but<01:20:53.880> it's<01:20:54.659> important<01:20:55.020> to<01:20:55.260> let<01:20:55.380> the<01:20:55.560> kidnap<01:20:55.920> to 01:20:56.090 --> 01:20:56.100 align:start position:0% but it's important to let the kidnap to 01:20:56.100 --> 01:20:57.770 align:start position:0% but it's important to let the kidnap to explore<01:20:56.400> freely<01:20:56.760> at<01:20:57.060> the<01:20:57.239> same<01:20:57.300> time<01:20:57.420> that<01:20:57.659> you 01:20:57.770 --> 01:20:57.780 align:start position:0% explore freely at the same time that you 01:20:57.780 --> 01:21:00.290 align:start position:0% explore freely at the same time that you are<01:20:57.900> allowing<01:20:58.320> information<01:20:58.860> so<01:20:59.820> it's<01:21:00.000> it's 01:21:00.290 --> 01:21:00.300 align:start position:0% are allowing information so it's it's 01:21:00.300 --> 01:21:04.130 align:start position:0% are allowing information so it's it's actually<01:21:00.600> important<01:21:01.320> to<01:21:02.040> know<01:21:02.880> that<01:21:03.239> as<01:21:03.900> an 01:21:04.130 --> 01:21:04.140 align:start position:0% actually important to know that as an 01:21:04.140 --> 01:21:06.530 align:start position:0% actually important to know that as an auditor<01:21:04.560> or<01:21:04.739> as<01:21:04.920> a<01:21:05.040> developer<01:21:05.460> you<01:21:06.000> are<01:21:06.120> adding 01:21:06.530 --> 01:21:06.540 align:start position:0% auditor or as a developer you are adding 01:21:06.540 --> 01:21:08.930 align:start position:0% auditor or as a developer you are adding information<01:21:06.719> into<01:21:07.140> into<01:21:07.560> not<01:21:08.219> just<01:21:08.460> using<01:21:08.820> it 01:21:08.930 --> 01:21:08.940 align:start position:0% information into into not just using it 01:21:08.940 --> 01:21:11.930 align:start position:0% information into into not just using it as<01:21:09.120> a<01:21:09.300> black<01:21:09.360> box<01:21:09.620> right<01:21:10.620> so<01:21:11.219> every<01:21:11.580> state 01:21:11.930 --> 01:21:11.940 align:start position:0% as a black box right so every state 01:21:11.940 --> 01:21:14.270 align:start position:0% as a black box right so every state transition<01:21:12.420> that<01:21:13.020> is<01:21:13.199> non-trivial<01:21:13.860> to<01:21:14.100> find 01:21:14.270 --> 01:21:14.280 align:start position:0% transition that is non-trivial to find 01:21:14.280 --> 01:21:17.270 align:start position:0% transition that is non-trivial to find or<01:21:14.820> is<01:21:15.060> really<01:21:15.239> really<01:21:15.420> important<01:21:15.980> you<01:21:16.980> you 01:21:17.270 --> 01:21:17.280 align:start position:0% or is really really important you you 01:21:17.280 --> 01:21:20.149 align:start position:0% or is really really important you you can<01:21:17.520> have<01:21:17.699> it<01:21:17.880> and<01:21:18.420> make<01:21:18.719> sure<01:21:18.960> that<01:21:19.320> it<01:21:19.980> can 01:21:20.149 --> 01:21:20.159 align:start position:0% can have it and make sure that it can 01:21:20.159 --> 01:21:22.010 align:start position:0% can have it and make sure that it can eventually<01:21:20.580> execute<01:21:21.120> it<01:21:21.300> because<01:21:21.540> it's<01:21:21.780> going 01:21:22.010 --> 01:21:22.020 align:start position:0% eventually execute it because it's going 01:21:22.020 --> 01:21:24.470 align:start position:0% eventually execute it because it's going to<01:21:22.140> be<01:21:22.320> another<01:21:22.560> another<01:21:22.980> transaction<01:21:23.580> to<01:21:23.940> to 01:21:24.470 --> 01:21:24.480 align:start position:0% to be another another transaction to to 01:21:24.480 --> 01:21:27.050 align:start position:0% to be another another transaction to to execute<01:21:24.840> but<01:21:25.320> at<01:21:25.500> the<01:21:25.620> same<01:21:25.800> time<01:21:26.040> you<01:21:26.699> want<01:21:26.940> to 01:21:27.050 --> 01:21:27.060 align:start position:0% execute but at the same time you want to 01:21:27.060 --> 01:21:29.750 align:start position:0% execute but at the same time you want to allow<01:21:27.480> the<01:21:27.780> tool<01:21:28.199> to<01:21:28.560> explore<01:21:28.920> things<01:21:29.520> that 01:21:29.750 --> 01:21:29.760 align:start position:0% allow the tool to explore things that 01:21:29.760 --> 01:21:31.850 align:start position:0% allow the tool to explore things that you<01:21:29.940> don't<01:21:30.060> expect<01:21:30.300> because<01:21:31.020> if<01:21:31.380> you<01:21:31.560> just 01:21:31.850 --> 01:21:31.860 align:start position:0% you don't expect because if you just 01:21:31.860 --> 01:21:34.970 align:start position:0% you don't expect because if you just restrict<01:21:32.400> says<01:21:33.239> I<01:21:33.659> only<01:21:33.780> expect<01:21:34.080> users<01:21:34.620> to<01:21:34.800> do 01:21:34.970 --> 01:21:34.980 align:start position:0% restrict says I only expect users to do 01:21:34.980 --> 01:21:38.450 align:start position:0% restrict says I only expect users to do these<01:21:35.280> type<01:21:35.400> of<01:21:35.520> deposits<01:21:36.239> then<01:21:37.140> you<01:21:37.560> can<01:21:37.739> you 01:21:38.450 --> 01:21:38.460 align:start position:0% these type of deposits then you can you 01:21:38.460 --> 01:21:40.850 align:start position:0% these type of deposits then you can you can<01:21:38.580> be<01:21:38.880> surprised<01:21:39.360> later<01:21:39.600> because<01:21:40.440> there 01:21:40.850 --> 01:21:40.860 align:start position:0% can be surprised later because there 01:21:40.860 --> 01:21:42.830 align:start position:0% can be surprised later because there there<01:21:41.159> is<01:21:41.460> a<01:21:41.820> way<01:21:41.940> to<01:21:42.239> break<01:21:42.360> your<01:21:42.600> your 01:21:42.830 --> 01:21:42.840 align:start position:0% there is a way to break your your 01:21:42.840 --> 01:21:44.510 align:start position:0% there is a way to break your your property<01:21:43.260> using<01:21:43.739> things<01:21:44.040> that<01:21:44.280> you<01:21:44.400> don't 01:21:44.510 --> 01:21:44.520 align:start position:0% property using things that you don't 01:21:44.520 --> 01:21:45.770 align:start position:0% property using things that you don't expect 01:21:45.770 --> 01:21:45.780 align:start position:0% expect 01:21:45.780 --> 01:21:47.709 align:start position:0% expect okay<01:21:46.380> thanks 01:21:47.709 --> 01:21:47.719 align:start position:0% okay thanks 01:21:47.719 --> 01:21:50.090 align:start position:0% okay thanks and<01:21:48.719> it<01:21:49.020> comes<01:21:49.260> down<01:21:49.380> to<01:21:49.560> the<01:21:49.739> previous 01:21:50.090 --> 01:21:50.100 align:start position:0% and it comes down to the previous 01:21:50.100 --> 01:21:52.910 align:start position:0% and it comes down to the previous question<01:21:50.520> where<01:21:50.940> either<01:21:51.659> you<01:21:51.960> start<01:21:52.260> with<01:21:52.560> a 01:21:52.910 --> 01:21:52.920 align:start position:0% question where either you start with a 01:21:52.920 --> 01:21:54.410 align:start position:0% question where either you start with a lot<01:21:53.040> of<01:21:53.159> requirements<01:21:53.760> and<01:21:53.940> a<01:21:54.120> lot<01:21:54.179> of<01:21:54.239> you 01:21:54.410 --> 01:21:54.420 align:start position:0% lot of requirements and a lot of you 01:21:54.420 --> 01:21:55.669 align:start position:0% lot of requirements and a lot of you know<01:21:54.540> restriction<01:21:54.900> in<01:21:55.140> what<01:21:55.320> you<01:21:55.440> are<01:21:55.560> trying 01:21:55.669 --> 01:21:55.679 align:start position:0% know restriction in what you are trying 01:21:55.679 --> 01:21:58.610 align:start position:0% know restriction in what you are trying to<01:21:55.860> explore<01:21:56.159> and<01:21:57.060> if<01:21:57.659> it<01:21:57.840> odds<01:21:58.320> you<01:21:58.380> are<01:21:58.560> going 01:21:58.610 --> 01:21:58.620 align:start position:0% to explore and if it odds you are going 01:21:58.620 --> 01:22:01.250 align:start position:0% to explore and if it odds you are going to<01:21:58.739> remove<01:21:59.340> some<01:21:59.699> of<01:21:59.820> the<01:21:59.940> restriction<01:22:00.360> or<01:22:01.020> you 01:22:01.250 --> 01:22:01.260 align:start position:0% to remove some of the restriction or you 01:22:01.260 --> 01:22:02.930 align:start position:0% to remove some of the restriction or you start<01:22:01.380> this<01:22:01.560> opposing<01:22:01.980> Direction<01:22:02.100> you<01:22:02.699> don't 01:22:02.930 --> 01:22:02.940 align:start position:0% start this opposing Direction you don't 01:22:02.940 --> 01:22:04.850 align:start position:0% start this opposing Direction you don't have<01:22:03.060> any<01:22:03.179> restriction<01:22:03.719> and<01:22:04.080> you<01:22:04.260> know<01:22:04.380> you<01:22:04.620> go 01:22:04.850 --> 01:22:04.860 align:start position:0% have any restriction and you know you go 01:22:04.860 --> 01:22:16.850 align:start position:0% have any restriction and you know you go more<01:22:05.460> and<01:22:05.640> more<01:22:05.820> restricted 01:22:16.850 --> 01:22:16.860 align:start position:0% 01:22:16.860 --> 01:22:45.229 align:start position:0% foreign 01:22:45.229 --> 01:22:45.239 align:start position:0% 01:22:45.239 --> 01:22:51.189 align:start position:0% yeah 01:22:51.189 --> 01:22:51.199 align:start position:0% 01:22:51.199 --> 01:22:57.430 align:start position:0% thank<01:22:52.199> you 01:22:57.430 --> 01:22:57.440 align:start position:0% 01:22:57.440 --> 01:22:59.110 align:start position:0% okay 01:22:59.110 --> 01:22:59.120 align:start position:0% okay 01:22:59.120 --> 01:23:02.870 align:start position:0% okay so<01:23:00.120> did<01:23:00.239> anyone<01:23:00.900> manage<01:23:01.500> to<01:23:01.620> at<01:23:01.860> least<01:23:02.040> uh 01:23:02.870 --> 01:23:02.880 align:start position:0% so did anyone manage to at least uh 01:23:02.880 --> 01:23:06.410 align:start position:0% so did anyone manage to at least uh Still<01:23:03.300> Still<01:23:03.719> start<01:23:04.620> to<01:23:05.239> create<01:23:06.239> the 01:23:06.410 --> 01:23:06.420 align:start position:0% Still Still start to create the 01:23:06.420 --> 01:23:09.169 align:start position:0% Still Still start to create the Constructor<01:23:06.780> or<01:23:07.140> even<01:23:07.440> run<01:23:07.679> it<01:23:07.920> uh<01:23:08.580> to<01:23:09.000> have 01:23:09.169 --> 01:23:09.179 align:start position:0% Constructor or even run it uh to have 01:23:09.179 --> 01:23:10.430 align:start position:0% Constructor or even run it uh to have some 01:23:10.430 --> 01:23:10.440 align:start position:0% some 01:23:10.440 --> 01:23:13.010 align:start position:0% some some<01:23:10.739> invariant 01:23:13.010 --> 01:23:13.020 align:start position:0% some invariant 01:23:13.020 --> 01:23:15.290 align:start position:0% some invariant or<01:23:13.560> even<01:23:13.679> think<01:23:13.920> about<01:23:14.100> the<01:23:14.400> invariant<01:23:15.120> that 01:23:15.290 --> 01:23:15.300 align:start position:0% or even think about the invariant that 01:23:15.300 --> 01:23:24.490 align:start position:0% or even think about the invariant that you<01:23:15.420> need 01:23:24.490 --> 01:23:24.500 align:start position:0% 01:23:24.500 --> 01:23:29.470 align:start position:0% thank<01:23:25.500> you 01:23:29.470 --> 01:23:29.480 align:start position:0% 01:23:29.480 --> 01:23:32.330 align:start position:0% so<01:23:30.480> in<01:23:30.719> a<01:23:31.080> couple<01:23:31.140> of<01:23:31.260> minutes<01:23:31.440> we'll<01:23:31.739> go<01:23:31.980> over 01:23:32.330 --> 01:23:32.340 align:start position:0% so in a couple of minutes we'll go over 01:23:32.340 --> 01:23:35.390 align:start position:0% so in a couple of minutes we'll go over the<01:23:32.640> conclusions<01:23:33.239> and<01:23:33.960> I<01:23:34.199> will<01:23:34.320> show<01:23:34.620> the<01:23:34.920> the 01:23:35.390 --> 01:23:35.400 align:start position:0% the conclusions and I will show the the 01:23:35.400 --> 01:23:37.669 align:start position:0% the conclusions and I will show the the solution 01:23:37.669 --> 01:23:37.679 align:start position:0% solution 01:23:37.679 --> 01:23:43.550 align:start position:0% solution um 01:23:43.550 --> 01:23:43.560 align:start position:0% 01:23:43.560 --> 01:23:45.169 align:start position:0% but<01:23:43.860> yeah<01:23:44.040> happy<01:23:44.219> to<01:23:44.400> take<01:23:44.520> any<01:23:44.640> additional 01:23:45.169 --> 01:23:45.179 align:start position:0% but yeah happy to take any additional 01:23:45.179 --> 01:23:58.610 align:start position:0% but yeah happy to take any additional questions 01:23:58.610 --> 01:23:58.620 align:start position:0% 01:23:58.620 --> 01:24:18.590 align:start position:0% thank<01:23:58.739> you 01:24:18.590 --> 01:24:18.600 align:start position:0% 01:24:18.600 --> 01:24:22.550 align:start position:0% just<01:24:19.440> from<01:24:19.739> an<01:24:19.920> implementation<01:24:20.900> uh<01:24:21.900> side<01:24:22.260> I'm 01:24:22.550 --> 01:24:22.560 align:start position:0% just from an implementation uh side I'm 01:24:22.560 --> 01:24:23.689 align:start position:0% just from an implementation uh side I'm curious<01:24:22.860> what 01:24:23.689 --> 01:24:23.699 align:start position:0% curious what 01:24:23.699 --> 01:24:26.930 align:start position:0% curious what um<01:24:23.960> what<01:24:24.960> actual<01:24:25.260> like<01:24:25.739> virtual<01:24:26.340> machine<01:24:26.580> do 01:24:26.930 --> 01:24:26.940 align:start position:0% um what actual like virtual machine do 01:24:26.940 --> 01:24:32.350 align:start position:0% um what actual like virtual machine do you<01:24:27.120> use<01:24:27.239> to<01:24:27.540> deploy<01:24:27.900> and<01:24:28.140> execute<01:24:28.739> contracts 01:24:32.350 --> 01:24:32.360 align:start position:0% 01:24:32.360 --> 01:24:37.250 align:start position:0% so<01:24:33.360> we<01:24:34.140> we<01:24:34.320> use<01:24:34.560> havm<01:24:35.699> uh<01:24:36.600> which<01:24:36.840> is<01:24:37.020> the 01:24:37.250 --> 01:24:37.260 align:start position:0% so we we use havm uh which is the 01:24:37.260 --> 01:24:39.590 align:start position:0% so we we use havm uh which is the Virtual<01:24:37.620> Machine<01:24:37.860> written<01:24:38.699> in<01:24:38.820> Haskell<01:24:39.239> I 01:24:39.590 --> 01:24:39.600 align:start position:0% Virtual Machine written in Haskell I 01:24:39.600 --> 01:24:42.649 align:start position:0% Virtual Machine written in Haskell I know<01:24:39.780> that<01:24:40.080> it's<01:24:40.800> in<01:24:40.980> the<01:24:41.159> process<01:24:41.340> of<01:24:41.699> uh 01:24:42.649 --> 01:24:42.659 align:start position:0% know that it's in the process of uh 01:24:42.659 --> 01:24:45.470 align:start position:0% know that it's in the process of uh improving<01:24:43.320> and<01:24:43.679> rewriting<01:24:44.640> so<01:24:44.820> it<01:24:44.940> was<01:24:45.120> moved 01:24:45.470 --> 01:24:45.480 align:start position:0% improving and rewriting so it was moved 01:24:45.480 --> 01:24:48.189 align:start position:0% improving and rewriting so it was moved from<01:24:45.719> the<01:24:46.020> adaptable<01:24:46.800> into<01:24:47.159> the<01:24:47.400> ethereum 01:24:48.189 --> 01:24:48.199 align:start position:0% from the adaptable into the ethereum 01:24:48.199 --> 01:24:51.530 align:start position:0% from the adaptable into the ethereum repository<01:24:49.199> so<01:24:49.560> we<01:24:49.920> are<01:24:50.159> eager<01:24:50.520> to<01:24:50.820> test<01:24:51.120> new 01:24:51.530 --> 01:24:51.540 align:start position:0% repository so we are eager to test new 01:24:51.540 --> 01:24:55.070 align:start position:0% repository so we are eager to test new features 01:24:55.070 --> 01:24:55.080 align:start position:0% 01:24:55.080 --> 01:24:57.709 align:start position:0% but<01:24:55.500> yeah<01:24:56.159> um<01:24:56.280> if<01:24:56.640> you<01:24:56.820> use<01:24:57.000> the<01:24:57.300> Tino 01:24:57.709 --> 01:24:57.719 align:start position:0% but yeah um if you use the Tino 01:24:57.719 --> 01:25:00.350 align:start position:0% but yeah um if you use the Tino companion<01:24:58.620> tool<01:24:58.980> to<01:24:59.400> deploy<01:25:00.000> your<01:25:00.120> contract 01:25:00.350 --> 01:25:00.360 align:start position:0% companion tool to deploy your contract 01:25:00.360 --> 01:25:03.229 align:start position:0% companion tool to deploy your contract it's<01:25:00.540> going<01:25:00.719> to<01:25:00.780> use<01:25:00.900> ganache 01:25:03.229 --> 01:25:03.239 align:start position:0% it's going to use ganache 01:25:03.239 --> 01:25:05.510 align:start position:0% it's going to use ganache um and<01:25:04.080> you<01:25:04.199> will<01:25:04.380> serialize<01:25:04.860> into<01:25:05.040> a<01:25:05.280> Json 01:25:05.510 --> 01:25:05.520 align:start position:0% um and you will serialize into a Json 01:25:05.520 --> 01:25:08.149 align:start position:0% um and you will serialize into a Json file<01:25:05.880> and<01:25:06.300> you<01:25:06.420> can<01:25:06.540> then<01:25:06.659> load<01:25:07.080> it<01:25:07.199> into<01:25:07.679> into 01:25:08.149 --> 01:25:08.159 align:start position:0% file and you can then load it into into 01:25:08.159 --> 01:25:12.750 align:start position:0% file and you can then load it into into that 01:25:12.750 --> 01:25:12.760 align:start position:0% 01:25:12.760 --> 01:25:15.530 align:start position:0% [Music] 01:25:15.530 --> 01:25:15.540 align:start position:0% [Music] 01:25:15.540 --> 01:25:18.990 align:start position:0% [Music] okay 01:25:18.990 --> 01:25:19.000 align:start position:0% 01:25:19.000 --> 01:25:34.790 align:start position:0% [Music] 01:25:34.790 --> 01:25:34.800 align:start position:0% 01:25:34.800 --> 01:25:38.450 align:start position:0% uh<01:25:35.520> solution<01:25:35.940> okay<01:25:36.739> yeah<01:25:37.739> we're<01:25:37.920> going<01:25:38.340> to 01:25:38.450 --> 01:25:38.460 align:start position:0% uh solution okay yeah we're going to 01:25:38.460 --> 01:25:41.090 align:start position:0% uh solution okay yeah we're going to quickly<01:25:39.120> go<01:25:39.360> over<01:25:39.480> the<01:25:39.719> solution<01:25:40.080> uh<01:25:40.679> so<01:25:40.920> we 01:25:41.090 --> 01:25:41.100 align:start position:0% quickly go over the solution uh so we 01:25:41.100 --> 01:25:43.550 align:start position:0% quickly go over the solution uh so we can<01:25:41.280> have<01:25:41.640> a<01:25:41.880> couple<01:25:41.940> of<01:25:42.060> minutes<01:25:42.300> for<01:25:42.780> for 01:25:43.550 --> 01:25:43.560 align:start position:0% can have a couple of minutes for for 01:25:43.560 --> 01:25:46.430 align:start position:0% can have a couple of minutes for for this<01:25:43.860> so<01:25:44.280> the<01:25:44.520> solution<01:25:44.760> requires<01:25:45.420> first<01:25:45.900> to 01:25:46.430 --> 01:25:46.440 align:start position:0% this so the solution requires first to 01:25:46.440 --> 01:25:49.130 align:start position:0% this so the solution requires first to uh<01:25:47.159> deploy<01:25:47.699> have<01:25:48.179> a<01:25:48.300> contract<01:25:48.540> with<01:25:48.780> enough 01:25:49.130 --> 01:25:49.140 align:start position:0% uh deploy have a contract with enough 01:25:49.140 --> 01:25:53.270 align:start position:0% uh deploy have a contract with enough amount<01:25:49.560> of<01:25:49.679> heater<01:25:50.420> uh<01:25:51.420> to<01:25:51.840> to<01:25:52.140> match<01:25:52.739> what<01:25:53.100> is 01:25:53.270 --> 01:25:53.280 align:start position:0% amount of heater uh to to match what is 01:25:53.280 --> 01:25:55.010 align:start position:0% amount of heater uh to to match what is deployed 01:25:55.010 --> 01:25:55.020 align:start position:0% deployed 01:25:55.020 --> 01:25:56.870 align:start position:0% deployed um<01:25:55.080> and<01:25:56.040> then 01:25:56.870 --> 01:25:56.880 align:start position:0% um and then 01:25:56.880 --> 01:26:00.709 align:start position:0% um and then um<01:25:56.940> you<01:25:57.239> can<01:25:57.360> see<01:25:57.600> here<01:25:58.040> uh<01:25:59.040> in<01:25:59.460> we<01:25:59.880> we<01:25:59.940> deployed 01:26:00.709 --> 01:26:00.719 align:start position:0% um you can see here uh in we we deployed 01:26:00.719 --> 01:26:04.189 align:start position:0% um you can see here uh in we we deployed all<01:26:01.199> the<01:26:01.320> contracts<01:26:01.739> that<01:26:01.920> we<01:26:02.100> need<01:26:02.280> and<01:26:02.580> send 01:26:04.189 --> 01:26:04.199 align:start position:0% all the contracts that we need and send 01:26:04.199 --> 01:26:07.070 align:start position:0% all the contracts that we need and send um<01:26:04.320> the<01:26:04.860> amount<01:26:05.100> of<01:26:05.219> eater<01:26:05.880> that<01:26:06.540> every 01:26:07.070 --> 01:26:07.080 align:start position:0% um the amount of eater that every 01:26:07.080 --> 01:26:10.070 align:start position:0% um the amount of eater that every contract<01:26:07.560> needs<01:26:07.920> and<01:26:08.580> then<01:26:08.760> what<01:26:09.120> is<01:26:09.300> uh<01:26:09.719> what 01:26:10.070 --> 01:26:10.080 align:start position:0% contract needs and then what is uh what 01:26:10.080 --> 01:26:12.050 align:start position:0% contract needs and then what is uh what we're<01:26:10.320> going<01:26:10.620> to<01:26:10.739> use<01:26:11.040> we're<01:26:11.460> going<01:26:11.639> to<01:26:11.760> use<01:26:11.820> a 01:26:12.050 --> 01:26:12.060 align:start position:0% we're going to use we're going to use a 01:26:12.060 --> 01:26:13.430 align:start position:0% we're going to use we're going to use a simple<01:26:12.179> very<01:26:12.420> simple<01:26:12.600> property<01:26:13.020> that<01:26:13.320> is 01:26:13.430 --> 01:26:13.440 align:start position:0% simple very simple property that is 01:26:13.440 --> 01:26:15.410 align:start position:0% simple very simple property that is going<01:26:13.620> to<01:26:13.679> say<01:26:13.860> that<01:26:14.219> the<01:26:14.760> balance<01:26:15.060> of<01:26:15.239> the 01:26:15.410 --> 01:26:15.420 align:start position:0% going to say that the balance of the 01:26:15.420 --> 01:26:18.649 align:start position:0% going to say that the balance of the receiver<01:26:15.780> is<01:26:16.500> at<01:26:16.739> least<01:26:16.860> 10<01:26:17.219> liter<01:26:17.699> so<01:26:18.300> we 01:26:18.649 --> 01:26:18.659 align:start position:0% receiver is at least 10 liter so we 01:26:18.659 --> 01:26:21.830 align:start position:0% receiver is at least 10 liter so we don't<01:26:18.840> actually<01:26:19.380> need<01:26:20.280> to<01:26:20.520> follow<01:26:21.300> exactly 01:26:21.830 --> 01:26:21.840 align:start position:0% don't actually need to follow exactly 01:26:21.840 --> 01:26:24.229 align:start position:0% don't actually need to follow exactly what<01:26:22.199> the<01:26:22.440> exercise<01:26:22.679> says<01:26:23.159> about<01:26:23.280> draining 01:26:24.229 --> 01:26:24.239 align:start position:0% what the exercise says about draining 01:26:24.239 --> 01:26:27.530 align:start position:0% what the exercise says about draining completely<01:26:24.780> the<01:26:25.139> contract<01:26:25.500> if<01:26:26.280> we<01:26:26.460> have<01:26:26.760> one 01:26:27.530 --> 01:26:27.540 align:start position:0% completely the contract if we have one 01:26:27.540 --> 01:26:29.689 align:start position:0% completely the contract if we have one transaction<01:26:27.960> that<01:26:28.260> allows<01:26:28.620> you<01:26:28.739> to<01:26:28.920> reduce 01:26:29.689 --> 01:26:29.699 align:start position:0% transaction that allows you to reduce 01:26:29.699 --> 01:26:32.870 align:start position:0% transaction that allows you to reduce the<01:26:30.120> balance<01:26:30.480> of<01:26:30.900> the<01:26:31.139> receiver<01:26:31.500> then<01:26:32.400> then 01:26:32.870 --> 01:26:32.880 align:start position:0% the balance of the receiver then then 01:26:32.880 --> 01:26:36.110 align:start position:0% the balance of the receiver then then it's<01:26:33.480> then<01:26:33.840> something<01:26:34.080> is<01:26:34.380> wrong<01:26:34.679> and<01:26:35.340> uh 01:26:36.110 --> 01:26:36.120 align:start position:0% it's then something is wrong and uh 01:26:36.120 --> 01:26:37.970 align:start position:0% it's then something is wrong and uh definitely<01:26:36.480> uh<01:26:37.020> it<01:26:37.260> will<01:26:37.320> it<01:26:37.500> will<01:26:37.739> eventually 01:26:37.970 --> 01:26:37.980 align:start position:0% definitely uh it will it will eventually 01:26:37.980 --> 01:26:40.010 align:start position:0% definitely uh it will it will eventually be<01:26:38.219> drained<01:26:38.639> so 01:26:40.010 --> 01:26:40.020 align:start position:0% be drained so 01:26:40.020 --> 01:26:43.550 align:start position:0% be drained so yeah<01:26:41.000> so<01:26:42.000> quickly<01:26:42.300> if<01:26:42.480> you<01:26:42.600> run<01:26:42.780> it<01:26:43.020> you<01:26:43.440> will 01:26:43.550 --> 01:26:43.560 align:start position:0% yeah so quickly if you run it you will 01:26:43.560 --> 01:26:46.129 align:start position:0% yeah so quickly if you run it you will see<01:26:43.800> something<01:26:44.040> like<01:26:44.280> this 01:26:46.129 --> 01:26:46.139 align:start position:0% see something like this 01:26:46.139 --> 01:26:49.189 align:start position:0% see something like this um<01:26:46.199> in<01:26:46.679> which<01:26:46.800> well<01:26:47.159> the<01:26:47.580> uh<01:26:47.719> deflection<01:26:48.719> has<01:26:49.020> a 01:26:49.189 --> 01:26:49.199 align:start position:0% um in which well the uh deflection has a 01:26:49.199 --> 01:26:52.070 align:start position:0% um in which well the uh deflection has a has<01:26:49.380> a<01:26:49.560> parameter<01:26:49.980> that<01:26:50.280> is<01:26:50.460> the<01:26:50.639> the<01:26:51.300> borrower 01:26:52.070 --> 01:26:52.080 align:start position:0% has a parameter that is the the borrower 01:26:52.080 --> 01:26:56.090 align:start position:0% has a parameter that is the the borrower and<01:26:52.620> we<01:26:52.739> can<01:26:52.920> control<01:26:53.159> this<01:26:53.580> to<01:26:54.060> in<01:26:54.540> order<01:26:54.659> to 01:26:56.090 --> 01:26:56.100 align:start position:0% and we can control this to in order to 01:26:56.100 --> 01:26:59.030 align:start position:0% and we can control this to in order to um<01:26:56.159> reduce<01:26:56.760> the<01:26:57.179> amount<01:26:57.420> of<01:26:57.659> balance 01:26:59.030 --> 01:26:59.040 align:start position:0% um reduce the amount of balance 01:26:59.040 --> 01:27:01.490 align:start position:0% um reduce the amount of balance all<01:26:59.580> right<01:26:59.760> uh<01:27:00.480> so<01:27:00.659> yeah<01:27:00.840> you<01:27:01.020> want<01:27:01.139> to<01:27:01.260> go<01:27:01.380> into 01:27:01.490 --> 01:27:01.500 align:start position:0% all right uh so yeah you want to go into 01:27:01.500 --> 01:27:06.709 align:start position:0% all right uh so yeah you want to go into the<01:27:01.800> conclusion<01:27:02.460> okay 01:27:06.709 --> 01:27:06.719 align:start position:0% 01:27:06.719 --> 01:27:08.270 align:start position:0% um<01:27:06.840> yeah<01:27:07.080> we're<01:27:07.260> the<01:27:07.500> second<01:27:07.620> exercise<01:27:07.860> on 01:27:08.270 --> 01:27:08.280 align:start position:0% um yeah we're the second exercise on 01:27:08.280 --> 01:27:10.790 align:start position:0% um yeah we're the second exercise on them<01:27:08.400> ruinable<01:27:08.880> D5<01:27:09.300> but<01:27:09.600> uh<01:27:10.320> we<01:27:10.560> are<01:27:10.679> running 01:27:10.790 --> 01:27:10.800 align:start position:0% them ruinable D5 but uh we are running 01:27:10.800 --> 01:27:12.950 align:start position:0% them ruinable D5 but uh we are running out<01:27:10.980> of<01:27:11.100> time 01:27:12.950 --> 01:27:12.960 align:start position:0% out of time 01:27:12.960 --> 01:27:14.810 align:start position:0% out of time this<01:27:13.440> idea<01:27:13.860> was<01:27:13.980> the<01:27:14.100> same<01:27:14.219> we<01:27:14.400> are<01:27:14.520> defining 01:27:14.810 --> 01:27:14.820 align:start position:0% this idea was the same we are defining 01:27:14.820 --> 01:27:16.250 align:start position:0% this idea was the same we are defining an<01:27:14.940> initialization 01:27:16.250 --> 01:27:16.260 align:start position:0% an initialization 01:27:16.260 --> 01:27:19.070 align:start position:0% an initialization which<01:27:17.100> was<01:27:17.340> a<01:27:17.460> bit<01:27:17.580> more<01:27:17.699> complex<01:27:18.060> and<01:27:18.600> if<01:27:18.900> you 01:27:19.070 --> 01:27:19.080 align:start position:0% which was a bit more complex and if you 01:27:19.080 --> 01:27:20.450 align:start position:0% which was a bit more complex and if you go<01:27:19.199> through<01:27:19.380> this<01:27:19.560> exercise<01:27:19.739> with<01:27:20.219> something 01:27:20.450 --> 01:27:20.460 align:start position:0% go through this exercise with something 01:27:20.460 --> 01:27:22.729 align:start position:0% go through this exercise with something a<01:27:20.760> bit<01:27:20.820> more<01:27:21.000> specific<01:27:21.420> is<01:27:22.139> that<01:27:22.320> there<01:27:22.440> is<01:27:22.620> a 01:27:22.729 --> 01:27:22.739 align:start position:0% a bit more specific is that there is a 01:27:22.739 --> 01:27:25.250 align:start position:0% a bit more specific is that there is a callback<01:27:23.100> from<01:27:24.060> the<01:27:24.239> contract<01:27:24.540> to<01:27:24.719> the<01:27:24.900> caller 01:27:25.250 --> 01:27:25.260 align:start position:0% callback from the contract to the caller 01:27:25.260 --> 01:27:27.169 align:start position:0% callback from the contract to the caller so<01:27:25.679> on<01:27:25.920> the<01:27:26.040> Kindle<01:27:26.400> test<01:27:26.580> you<01:27:26.760> need<01:27:26.940> to<01:27:27.000> have 01:27:27.169 --> 01:27:27.179 align:start position:0% so on the Kindle test you need to have 01:27:27.179 --> 01:27:28.910 align:start position:0% so on the Kindle test you need to have like<01:27:27.360> also<01:27:27.659> the<01:27:27.840> Callback<01:27:28.080> to<01:27:28.320> implement<01:27:28.560> the 01:27:28.910 --> 01:27:28.920 align:start position:0% like also the Callback to implement the 01:27:28.920 --> 01:27:30.410 align:start position:0% like also the Callback to implement the flashlight 01:27:30.410 --> 01:27:30.420 align:start position:0% flashlight 01:27:30.420 --> 01:27:31.270 align:start position:0% flashlight but<01:27:30.840> yeah 01:27:31.270 --> 01:27:31.280 align:start position:0% but yeah 01:27:31.280 --> 01:27:36.229 align:start position:0% but yeah [Music] 01:27:36.229 --> 01:27:36.239 align:start position:0% 01:27:36.239 --> 01:27:38.209 align:start position:0% so<01:27:36.540> this<01:27:36.659> is<01:27:36.780> something<01:27:37.080> we<01:27:37.440> kind<01:27:37.620> of<01:27:37.739> touch<01:27:37.980> on 01:27:38.209 --> 01:27:38.219 align:start position:0% so this is something we kind of touch on 01:27:38.219 --> 01:27:40.310 align:start position:0% so this is something we kind of touch on a<01:27:38.400> bit<01:27:38.520> during<01:27:38.699> your<01:27:38.940> discussion<01:27:39.360> what<01:27:40.139> about 01:27:40.310 --> 01:27:40.320 align:start position:0% a bit during your discussion what about 01:27:40.320 --> 01:27:42.410 align:start position:0% a bit during your discussion what about the<01:27:40.620> other<01:27:40.739> tools<01:27:41.280> so<01:27:41.639> there<01:27:41.940> are<01:27:42.120> a<01:27:42.179> couple<01:27:42.300> of 01:27:42.410 --> 01:27:42.420 align:start position:0% the other tools so there are a couple of 01:27:42.420 --> 01:27:44.750 align:start position:0% the other tools so there are a couple of other<01:27:42.659> further<01:27:43.199> out<01:27:43.500> there<01:27:43.739> there<01:27:44.159> is<01:27:44.400> Dub 01:27:44.750 --> 01:27:44.760 align:start position:0% other further out there there is Dub 01:27:44.760 --> 01:27:47.330 align:start position:0% other further out there there is Dub Brony<01:27:45.360> Foundry<01:27:46.020> at<01:27:46.620> least<01:27:46.739> this<01:27:46.860> one<01:27:47.040> are<01:27:47.219> open 01:27:47.330 --> 01:27:47.340 align:start position:0% Brony Foundry at least this one are open 01:27:47.340 --> 01:27:48.970 align:start position:0% Brony Foundry at least this one are open source 01:27:48.970 --> 01:27:48.980 align:start position:0% source 01:27:48.980 --> 01:27:53.090 align:start position:0% source this<01:27:49.980> funnel<01:27:50.460> might<01:27:50.699> be<01:27:50.880> a<01:27:51.060> bit<01:27:51.239> uh<01:27:52.020> better<01:27:52.620> for 01:27:53.090 --> 01:27:53.100 align:start position:0% this funnel might be a bit uh better for 01:27:53.100 --> 01:27:55.070 align:start position:0% this funnel might be a bit uh better for simple<01:27:53.400> tests<01:27:53.820> and<01:27:53.940> for<01:27:54.060> like<01:27:54.179> you<01:27:54.360> know<01:27:54.480> ease 01:27:55.070 --> 01:27:55.080 align:start position:0% simple tests and for like you know ease 01:27:55.080 --> 01:27:57.530 align:start position:0% simple tests and for like you know ease of<01:27:55.139> useful<01:27:55.620> uh<01:27:56.340> like<01:27:56.580> the<01:27:56.699> first<01:27:56.880> invariant 01:27:57.530 --> 01:27:57.540 align:start position:0% of useful uh like the first invariant 01:27:57.540 --> 01:27:59.030 align:start position:0% of useful uh like the first invariant because<01:27:57.840> they<01:27:58.080> are<01:27:58.199> integrated<01:27:58.500> within<01:27:58.920> the 01:27:59.030 --> 01:27:59.040 align:start position:0% because they are integrated within the 01:27:59.040 --> 01:28:01.189 align:start position:0% because they are integrated within the compilation<01:27:59.400> framework<01:27:59.940> but<01:28:00.600> in<01:28:00.900> the<01:28:01.020> long 01:28:01.189 --> 01:28:01.199 align:start position:0% compilation framework but in the long 01:28:01.199 --> 01:28:03.169 align:start position:0% compilation framework but in the long run<01:28:01.320> they<01:28:01.739> might<01:28:01.980> not<01:28:02.100> be<01:28:02.340> as<01:28:02.520> powerful<01:28:02.880> as<01:28:03.060> a 01:28:03.169 --> 01:28:03.179 align:start position:0% run they might not be as powerful as a 01:28:03.179 --> 01:28:04.910 align:start position:0% run they might not be as powerful as a Kinder<01:28:03.540> simply<01:28:04.020> because<01:28:04.199> we<01:28:04.440> have<01:28:04.620> you<01:28:04.800> know 01:28:04.910 --> 01:28:04.920 align:start position:0% Kinder simply because we have you know 01:28:04.920 --> 01:28:07.070 align:start position:0% Kinder simply because we have you know user<01:28:05.639> Kinder<01:28:05.940> for<01:28:06.120> a<01:28:06.179> couple<01:28:06.300> of<01:28:06.360> years<01:28:06.600> and<01:28:06.900> we 01:28:07.070 --> 01:28:07.080 align:start position:0% user Kinder for a couple of years and we 01:28:07.080 --> 01:28:09.110 align:start position:0% user Kinder for a couple of years and we have<01:28:07.260> tuned<01:28:07.800> it<01:28:07.920> you<01:28:08.159> know<01:28:08.219> where<01:28:08.460> that<01:28:08.760> it 01:28:09.110 --> 01:28:09.120 align:start position:0% have tuned it you know where that it 01:28:09.120 --> 01:28:11.770 align:start position:0% have tuned it you know where that it provides<01:28:09.540> the<01:28:10.380> best<01:28:10.500> value<01:28:10.739> that<01:28:11.040> we<01:28:11.159> can<01:28:11.280> do 01:28:11.770 --> 01:28:11.780 align:start position:0% provides the best value that we can do 01:28:11.780 --> 01:28:17.450 align:start position:0% provides the best value that we can do I'll<01:28:12.780> get<01:28:12.900> finished<01:28:13.139> okay<01:28:13.860> sorry<01:28:14.639> um<01:28:14.699> yeah 01:28:17.450 --> 01:28:17.460 align:start position:0% I'll get finished okay sorry um yeah 01:28:17.460 --> 01:28:21.830 align:start position:0% I'll get finished okay sorry um yeah okay<01:28:18.000> so<01:28:18.420> I<01:28:18.960> hope<01:28:19.199> you<01:28:19.320> enjoyed<01:28:19.800> the<01:28:20.639> workshop 01:28:21.830 --> 01:28:21.840 align:start position:0% okay so I hope you enjoyed the workshop 01:28:21.840 --> 01:28:23.450 align:start position:0% okay so I hope you enjoyed the workshop um<01:28:21.900> we<01:28:22.320> have<01:28:22.500> more<01:28:22.679> exercise<01:28:22.920> in<01:28:23.280> building 01:28:23.450 --> 01:28:23.460 align:start position:0% um we have more exercise in building 01:28:23.460 --> 01:28:24.950 align:start position:0% um we have more exercise in building secure<01:28:23.880> contract 01:28:24.950 --> 01:28:24.960 align:start position:0% secure contract 01:28:24.960 --> 01:28:26.629 align:start position:0% secure contract something<01:28:25.440> that<01:28:25.739> I<01:28:25.860> would<01:28:25.920> recommend<01:28:26.340> for<01:28:26.520> you 01:28:26.629 --> 01:28:26.639 align:start position:0% something that I would recommend for you 01:28:26.639 --> 01:28:28.370 align:start position:0% something that I would recommend for you is<01:28:26.820> to<01:28:26.940> try<01:28:27.120> to<01:28:27.239> write<01:28:27.420> invariant<01:28:27.960> you<01:28:28.139> know<01:28:28.260> in 01:28:28.370 --> 01:28:28.380 align:start position:0% is to try to write invariant you know in 01:28:28.380 --> 01:28:30.709 align:start position:0% is to try to write invariant you know in your<01:28:28.440> next<01:28:28.560> project<01:28:28.800> and<01:28:29.760> actually<01:28:30.000> who<01:28:30.540> is 01:28:30.709 --> 01:28:30.719 align:start position:0% your next project and actually who is 01:28:30.719 --> 01:28:32.570 align:start position:0% your next project and actually who is going<01:28:30.900> to<01:28:31.020> try<01:28:31.260> again<01:28:31.500> now<01:28:31.800> on<01:28:32.040> his<01:28:32.280> next 01:28:32.570 --> 01:28:32.580 align:start position:0% going to try again now on his next 01:28:32.580 --> 01:28:35.270 align:start position:0% going to try again now on his next project 01:28:35.270 --> 01:28:35.280 align:start position:0% 01:28:35.280 --> 01:28:37.490 align:start position:0% nice 01:28:37.490 --> 01:28:37.500 align:start position:0% nice 01:28:37.500 --> 01:28:39.720 align:start position:0% nice and<01:28:38.340> thank<01:28:38.520> you 01:28:39.720 --> 01:28:39.730 align:start position:0% and thank you 01:28:39.730 --> 01:28:42.590 align:start position:0% and thank you [Applause] 01:28:42.590 --> 01:28:42.600 align:start position:0% [Applause] 01:28:42.600 --> 01:28:44.570 align:start position:0% [Applause] So<01:28:43.260> today<01:28:43.800> we're<01:28:44.040> going<01:28:44.219> to<01:28:44.340> talk<01:28:44.460> about 01:28:44.570 --> 01:28:44.580 align:start position:0% So today we're going to talk about 01:28:44.580 --> 01:28:47.030 align:start position:0% So today we're going to talk about storage<01:28:44.940> proofs<01:28:45.420> I<01:28:45.900> want<01:28:45.960> to<01:28:46.139> introduce<01:28:46.560> this 01:28:47.030 --> 01:28:47.040 align:start position:0% storage proofs I want to introduce this 01:28:47.040 --> 01:28:49.330 align:start position:0% storage proofs I want to introduce this app 01:28:49.330 --> 01:28:49.340 align:start position:0% app 01:28:49.340 --> 01:28:50.890 align:start position:0% app yes 01:28:50.890 --> 01:28:50.900 align:start position:0% yes 01:28:50.900 --> 01:28:53.510 align:start position:0% yes I'm<01:28:51.900> gonna<01:28:52.020> present<01:28:52.500> you<01:28:52.679> storage<01:28:52.920> proofs<01:28:53.400> and 01:28:53.510 --> 01:28:53.520 align:start position:0% I'm gonna present you storage proofs and 01:28:53.520 --> 01:28:55.250 align:start position:0% I'm gonna present you storage proofs and explain<01:28:53.699> why<01:28:54.120> they're<01:28:54.360> cool<01:28:54.659> how<01:28:54.900> to<01:28:55.080> work 01:28:55.250 --> 01:28:55.260 align:start position:0% explain why they're cool how to work 01:28:55.260 --> 01:28:57.530 align:start position:0% explain why they're cool how to work with<01:28:55.560> them<01:28:55.860> why<01:28:56.400> you<01:28:56.639> need<01:28:56.760> to<01:28:56.880> link<01:28:57.120> to<01:28:57.420> work 01:28:57.530 --> 01:28:57.540 align:start position:0% with them why you need to link to work 01:28:57.540 --> 01:28:58.930 align:start position:0% with them why you need to link to work with<01:28:57.780> them 01:28:58.930 --> 01:28:58.940 align:start position:0% with them 01:28:58.940 --> 01:29:02.209 align:start position:0% with them and<01:28:59.940> yeah<01:29:00.360> a<01:29:00.780> bunch<01:29:00.960> of<01:29:01.080> other<01:29:01.380> things<01:29:01.739> why<01:29:02.100> is 01:29:02.209 --> 01:29:02.219 align:start position:0% and yeah a bunch of other things why is 01:29:02.219 --> 01:29:04.430 align:start position:0% and yeah a bunch of other things why is it<01:29:02.400> even<01:29:02.520> possible<01:29:03.000> all<01:29:03.840> the<01:29:04.020> complexities 01:29:04.430 --> 01:29:04.440 align:start position:0% it even possible all the complexities 01:29:04.440 --> 01:29:08.209 align:start position:0% it even possible all the complexities behind<01:29:04.920> the<01:29:05.100> trade-offs<01:29:06.000> and<01:29:06.780> so<01:29:06.900> on<01:29:07.080> so<01:29:07.440> a<01:29:08.040> few 01:29:08.209 --> 01:29:08.219 align:start position:0% behind the trade-offs and so on so a few 01:29:08.219 --> 01:29:10.189 align:start position:0% behind the trade-offs and so on so a few words<01:29:08.340> about<01:29:08.580> storage<01:29:08.820> Crews<01:29:09.300> why<01:29:09.840> I<01:29:10.080> really 01:29:10.189 --> 01:29:10.199 align:start position:0% words about storage Crews why I really 01:29:10.199 --> 01:29:12.530 align:start position:0% words about storage Crews why I really believe<01:29:10.380> that<01:29:10.560> they<01:29:10.739> are<01:29:10.860> cool<01:29:11.040> especially<01:29:11.760> uh 01:29:12.530 --> 01:29:12.540 align:start position:0% believe that they are cool especially uh 01:29:12.540 --> 01:29:14.810 align:start position:0% believe that they are cool especially uh nowadays<01:29:13.080> so<01:29:13.860> might<01:29:14.159> as<01:29:14.340> this<01:29:14.520> is<01:29:14.639> that 01:29:14.810 --> 01:29:14.820 align:start position:0% nowadays so might as this is that 01:29:14.820 --> 01:29:17.810 align:start position:0% nowadays so might as this is that ethereum<01:29:15.300> is<01:29:15.540> pretty<01:29:16.080> sharded<01:29:16.560> nowadays<01:29:17.159> and 01:29:17.810 --> 01:29:17.820 align:start position:0% ethereum is pretty sharded nowadays and 01:29:17.820 --> 01:29:20.390 align:start position:0% ethereum is pretty sharded nowadays and with<01:29:18.000> storage<01:29:18.239> truth<01:29:18.719> we<01:29:19.020> can<01:29:19.199> essentially 01:29:20.390 --> 01:29:20.400 align:start position:0% with storage truth we can essentially 01:29:20.400 --> 01:29:23.689 align:start position:0% with storage truth we can essentially read<01:29:21.060> the<01:29:21.659> state<01:29:21.840> in<01:29:22.440> a<01:29:22.679> almost<01:29:23.100> synchronous 01:29:23.689 --> 01:29:23.699 align:start position:0% read the state in a almost synchronous 01:29:23.699 --> 01:29:26.149 align:start position:0% read the state in a almost synchronous manner<01:29:24.120> which<01:29:24.659> is<01:29:24.840> a<01:29:25.260> pretty<01:29:25.560> pretty<01:29:25.860> nice 01:29:26.149 --> 01:29:26.159 align:start position:0% manner which is a pretty pretty nice 01:29:26.159 --> 01:29:27.430 align:start position:0% manner which is a pretty pretty nice thing<01:29:26.400> to<01:29:26.639> do 01:29:27.430 --> 01:29:27.440 align:start position:0% thing to do 01:29:27.440 --> 01:29:31.189 align:start position:0% thing to do given<01:29:28.440> the<01:29:28.980> circumstances 01:29:31.189 --> 01:29:31.199 align:start position:0% given the circumstances 01:29:31.199 --> 01:29:33.890 align:start position:0% given the circumstances um<01:29:31.260> yeah<01:29:32.100> and<01:29:32.639> maybe<01:29:32.880> also<01:29:33.480> let<01:29:33.659> me<01:29:33.780> explain 01:29:33.890 --> 01:29:33.900 align:start position:0% um yeah and maybe also let me explain 01:29:33.900 --> 01:29:36.530 align:start position:0% um yeah and maybe also let me explain why<01:29:34.199> is<01:29:34.380> it<01:29:34.500> even<01:29:34.620> possible<01:29:35.040> so<01:29:35.760> story<01:29:36.000> is 01:29:36.530 --> 01:29:36.540 align:start position:0% why is it even possible so story is 01:29:36.540 --> 01:29:38.030 align:start position:0% why is it even possible so story is essentially<01:29:36.840> this<01:29:37.080> idea<01:29:37.320> that<01:29:37.620> the<01:29:37.860> entire 01:29:38.030 --> 01:29:38.040 align:start position:0% essentially this idea that the entire 01:29:38.040 --> 01:29:39.770 align:start position:0% essentially this idea that the entire state<01:29:38.340> is<01:29:38.580> committed<01:29:38.940> in<01:29:39.060> a<01:29:39.179> cryptographic 01:29:39.770 --> 01:29:39.780 align:start position:0% state is committed in a cryptographic 01:29:39.780 --> 01:29:41.090 align:start position:0% state is committed in a cryptographic manner 01:29:41.090 --> 01:29:41.100 align:start position:0% manner 01:29:41.100 --> 01:29:42.649 align:start position:0% manner um<01:29:41.159> using<01:29:41.639> some<01:29:41.820> data<01:29:42.300> structure<01:29:42.540> like 01:29:42.649 --> 01:29:42.659 align:start position:0% um using some data structure like 01:29:42.659 --> 01:29:44.450 align:start position:0% um using some data structure like Miracle<01:29:43.020> trees<01:29:43.320> Marco<01:29:43.739> Patricia<01:29:43.980> trees<01:29:44.340> and 01:29:44.450 --> 01:29:44.460 align:start position:0% Miracle trees Marco Patricia trees and 01:29:44.460 --> 01:29:45.530 align:start position:0% Miracle trees Marco Patricia trees and so<01:29:44.580> on 01:29:45.530 --> 01:29:45.540 align:start position:0% so on 01:29:45.540 --> 01:29:47.149 align:start position:0% so on um<01:29:45.600> and<01:29:45.780> yeah<01:29:45.900> we<01:29:46.139> can<01:29:46.260> essentially<01:29:46.620> verify 01:29:47.149 --> 01:29:47.159 align:start position:0% um and yeah we can essentially verify 01:29:47.159 --> 01:29:50.450 align:start position:0% um and yeah we can essentially verify any<01:29:47.820> specific<01:29:48.300> piece<01:29:48.780> of<01:29:48.840> State<01:29:49.020> at<01:29:49.920> any<01:29:50.219> point 01:29:50.450 --> 01:29:50.460 align:start position:0% any specific piece of State at any point 01:29:50.460 --> 01:29:53.750 align:start position:0% any specific piece of State at any point in<01:29:50.699> time<01:29:50.880> on<01:29:51.540> any<01:29:51.840> domain<01:29:52.560> which<01:29:53.340> is<01:29:53.520> pretty 01:29:53.750 --> 01:29:53.760 align:start position:0% in time on any domain which is pretty 01:29:53.760 --> 01:29:55.669 align:start position:0% in time on any domain which is pretty nice<01:29:54.000> and<01:29:54.300> does<01:29:54.480> introduce<01:29:54.900> additional<01:29:55.320> trust 01:29:55.669 --> 01:29:55.679 align:start position:0% nice and does introduce additional trust 01:29:55.679 --> 01:29:57.290 align:start position:0% nice and does introduce additional trust assumptions<01:29:56.100> you<01:29:56.699> just<01:29:56.820> rely<01:29:57.120> on<01:29:57.239> the 01:29:57.290 --> 01:29:57.300 align:start position:0% assumptions you just rely on the 01:29:57.300 --> 01:29:59.870 align:start position:0% assumptions you just rely on the security<01:29:57.480> of<01:29:57.840> like<01:29:58.020> the<01:29:58.139> base<01:29:58.440> chain 01:29:59.870 --> 01:29:59.880 align:start position:0% security of like the base chain 01:29:59.880 --> 01:30:02.149 align:start position:0% security of like the base chain um<01:29:59.940> so<01:30:00.179> yeah<01:30:00.300> that's<01:30:00.719> like<01:30:01.139> storage<01:30:01.620> proofs 01:30:02.149 --> 01:30:02.159 align:start position:0% um so yeah that's like storage proofs 01:30:02.159 --> 01:30:04.610 align:start position:0% um so yeah that's like storage proofs tldr<01:30:02.760> where<01:30:03.060> they're<01:30:03.360> cool 01:30:04.610 --> 01:30:04.620 align:start position:0% tldr where they're cool 01:30:04.620 --> 01:30:08.290 align:start position:0% tldr where they're cool now<01:30:05.340> a<01:30:05.639> bit<01:30:05.760> of<01:30:05.940> like<01:30:06.120> sponsored<01:30:06.719> section<01:30:07.020> of 01:30:08.290 --> 01:30:08.300 align:start position:0% now a bit of like sponsored section of 01:30:08.300 --> 01:30:11.090 align:start position:0% now a bit of like sponsored section of sponsored<01:30:09.300> sections<01:30:09.780> so<01:30:10.080> uh<01:30:10.500> what<01:30:10.800> we're 01:30:11.090 --> 01:30:11.100 align:start position:0% sponsored sections so uh what we're 01:30:11.100 --> 01:30:14.330 align:start position:0% sponsored sections so uh what we're doing<01:30:11.219> at<01:30:11.400> harvardus<01:30:12.060> so<01:30:12.900> our<01:30:13.440> like<01:30:13.739> goal<01:30:14.219> is 01:30:14.330 --> 01:30:14.340 align:start position:0% doing at harvardus so our like goal is 01:30:14.340 --> 01:30:17.030 align:start position:0% doing at harvardus so our like goal is to<01:30:14.639> make<01:30:14.880> smart<01:30:15.719> contracts<01:30:16.199> sell<01:30:16.320> for<01:30:16.560> in<01:30:16.860> a 01:30:17.030 --> 01:30:17.040 align:start position:0% to make smart contracts sell for in a 01:30:17.040 --> 01:30:19.669 align:start position:0% to make smart contracts sell for in a way<01:30:17.159> by<01:30:18.120> providing<01:30:18.659> access<01:30:19.020> to<01:30:19.199> historical 01:30:19.669 --> 01:30:19.679 align:start position:0% way by providing access to historical 01:30:19.679 --> 01:30:20.930 align:start position:0% way by providing access to historical state 01:30:20.930 --> 01:30:20.940 align:start position:0% state 01:30:20.940 --> 01:30:23.870 align:start position:0% state uh<01:30:21.600> we<01:30:21.780> like<01:30:22.199> I<01:30:22.440> said<01:30:22.560> might<01:30:22.980> as<01:30:23.219> this<01:30:23.460> is<01:30:23.639> that 01:30:23.870 --> 01:30:23.880 align:start position:0% uh we like I said might as this is that 01:30:23.880 --> 01:30:25.669 align:start position:0% uh we like I said might as this is that ethereum<01:30:24.420> is<01:30:24.600> pretty<01:30:24.719> short<01:30:24.960> that<01:30:25.139> nowadays 01:30:25.669 --> 01:30:25.679 align:start position:0% ethereum is pretty short that nowadays 01:30:25.679 --> 01:30:27.950 align:start position:0% ethereum is pretty short that nowadays we<01:30:25.920> want<01:30:26.040> to<01:30:26.159> unchart<01:30:26.580> it<01:30:26.820> by<01:30:27.420> using<01:30:27.780> storage 01:30:27.950 --> 01:30:27.960 align:start position:0% we want to unchart it by using storage 01:30:27.960 --> 01:30:31.129 align:start position:0% we want to unchart it by using storage proofs<01:30:28.620> and<01:30:29.460> we<01:30:29.880> want<01:30:30.000> to<01:30:30.120> enable<01:30:30.420> synchronous 01:30:31.129 --> 01:30:31.139 align:start position:0% proofs and we want to enable synchronous 01:30:31.139 --> 01:30:32.990 align:start position:0% proofs and we want to enable synchronous data<01:30:31.500> reads<01:30:31.739> because<01:30:31.860> today<01:30:32.100> we<01:30:32.460> do<01:30:32.639> not<01:30:32.820> have 01:30:32.990 --> 01:30:33.000 align:start position:0% data reads because today we do not have 01:30:33.000 --> 01:30:35.629 align:start position:0% data reads because today we do not have really<01:30:33.300> nice<01:30:34.020> ways<01:30:34.380> to<01:30:34.560> make<01:30:34.800> synchronous 01:30:35.629 --> 01:30:35.639 align:start position:0% really nice ways to make synchronous 01:30:35.639 --> 01:30:37.669 align:start position:0% really nice ways to make synchronous data<01:30:36.060> access<01:30:36.120> without<01:30:36.480> introducing<01:30:37.139> New 01:30:37.669 --> 01:30:37.679 align:start position:0% data access without introducing New 01:30:37.679 --> 01:30:40.310 align:start position:0% data access without introducing New State<01:30:37.980> uh<01:30:38.400> new<01:30:38.639> trust<01:30:38.880> assumptions<01:30:39.300> so<01:30:40.139> yeah 01:30:40.310 --> 01:30:40.320 align:start position:0% State uh new trust assumptions so yeah 01:30:40.320 --> 01:30:42.229 align:start position:0% State uh new trust assumptions so yeah that's<01:30:40.500> we<01:30:40.739> do<01:30:40.920> and<01:30:41.040> how<01:30:41.219> we<01:30:41.340> achieve<01:30:41.699> that<01:30:41.820> we 01:30:42.229 --> 01:30:42.239 align:start position:0% that's we do and how we achieve that we 01:30:42.239 --> 01:30:44.090 align:start position:0% that's we do and how we achieve that we achieve<01:30:42.600> that<01:30:42.719> by<01:30:42.960> using<01:30:43.440> obviously<01:30:43.860> storage 01:30:44.090 --> 01:30:44.100 align:start position:0% achieve that by using obviously storage 01:30:44.100 --> 01:30:48.410 align:start position:0% achieve that by using obviously storage proofs<01:30:44.639> we<01:30:45.000> use<01:30:45.179> snark<01:30:45.480> Starks<01:30:46.139> and<01:30:46.679> NPC<01:30:47.420> I 01:30:48.410 --> 01:30:48.420 align:start position:0% proofs we use snark Starks and NPC I 01:30:48.420 --> 01:30:50.330 align:start position:0% proofs we use snark Starks and NPC I will<01:30:48.540> get<01:30:48.719> why<01:30:49.320> we<01:30:49.560> even<01:30:49.739> use<01:30:49.980> all<01:30:50.159> this 01:30:50.330 --> 01:30:50.340 align:start position:0% will get why we even use all this 01:30:50.340 --> 01:30:52.669 align:start position:0% will get why we even use all this tooling<01:30:50.760> but<01:30:51.480> first<01:30:51.900> a<01:30:52.139> few<01:30:52.260> words<01:30:52.440> about 01:30:52.669 --> 01:30:52.679 align:start position:0% tooling but first a few words about 01:30:52.679 --> 01:30:54.830 align:start position:0% tooling but first a few words about storage<01:30:52.980> rules<01:30:53.460> what<01:30:53.639> these<01:30:53.940> are<01:30:54.060> and<01:30:54.420> and<01:30:54.600> so 01:30:54.830 --> 01:30:54.840 align:start position:0% storage rules what these are and and so 01:30:54.840 --> 01:30:56.330 align:start position:0% storage rules what these are and and so on 01:30:56.330 --> 01:30:56.340 align:start position:0% on 01:30:56.340 --> 01:30:58.729 align:start position:0% on it's<01:30:56.940> so<01:30:57.120> tricky<01:30:57.480> actually<01:30:57.659> I<01:30:58.020> I<01:30:58.320> need<01:30:58.500> to<01:30:58.620> be 01:30:58.729 --> 01:30:58.739 align:start position:0% it's so tricky actually I I need to be 01:30:58.739 --> 01:31:01.310 align:start position:0% it's so tricky actually I I need to be multitasking<01:30:59.639> okay<01:31:00.239> so<01:31:00.600> uh<01:31:00.900> what<01:31:01.080> we're<01:31:01.199> gonna 01:31:01.310 --> 01:31:01.320 align:start position:0% multitasking okay so uh what we're gonna 01:31:01.320 --> 01:31:04.370 align:start position:0% multitasking okay so uh what we're gonna cover<01:31:01.620> in<01:31:02.159> today's<01:31:02.460> Workshop<01:31:03.000> so<01:31:03.900> all<01:31:04.199> the 01:31:04.370 --> 01:31:04.380 align:start position:0% cover in today's Workshop so all the 01:31:04.380 --> 01:31:05.990 align:start position:0% cover in today's Workshop so all the basics<01:31:04.739> required<01:31:05.340> to<01:31:05.460> like<01:31:05.699> understand 01:31:05.990 --> 01:31:06.000 align:start position:0% basics required to like understand 01:31:06.000 --> 01:31:09.590 align:start position:0% basics required to like understand properly<01:31:06.900> this<01:31:07.679> primitive<01:31:08.159> how<01:31:09.000> to<01:31:09.120> like<01:31:09.300> work 01:31:09.590 --> 01:31:09.600 align:start position:0% properly this primitive how to like work 01:31:09.600 --> 01:31:11.870 align:start position:0% properly this primitive how to like work with<01:31:09.840> it<01:31:10.020> uh<01:31:10.800> how<01:31:10.980> you<01:31:11.100> can<01:31:11.219> generate<01:31:11.580> these 01:31:11.870 --> 01:31:11.880 align:start position:0% with it uh how you can generate these 01:31:11.880 --> 01:31:14.149 align:start position:0% with it uh how you can generate these proofs<01:31:12.120> why<01:31:12.360> they're<01:31:12.600> pretty<01:31:12.900> useful<01:31:13.260> and<01:31:13.920> how 01:31:14.149 --> 01:31:14.159 align:start position:0% proofs why they're pretty useful and how 01:31:14.159 --> 01:31:16.970 align:start position:0% proofs why they're pretty useful and how actually<01:31:14.400> you<01:31:14.820> can<01:31:15.080> access<01:31:16.080> this<01:31:16.500> commitments 01:31:16.970 --> 01:31:16.980 align:start position:0% actually you can access this commitments 01:31:16.980 --> 01:31:18.649 align:start position:0% actually you can access this commitments I'll<01:31:17.100> get<01:31:17.280> later<01:31:17.460> what<01:31:17.880> we<01:31:18.360> call<01:31:18.480> the 01:31:18.649 --> 01:31:18.659 align:start position:0% I'll get later what we call the 01:31:18.659 --> 01:31:22.129 align:start position:0% I'll get later what we call the commitment<01:31:19.159> in<01:31:20.159> a<01:31:20.340> process<01:31:21.000> manner 01:31:22.129 --> 01:31:22.139 align:start position:0% commitment in a process manner 01:31:22.139 --> 01:31:24.950 align:start position:0% commitment in a process manner and<01:31:22.800> how<01:31:23.100> we<01:31:23.219> make<01:31:23.400> smart<01:31:23.639> contracts<01:31:24.300> software 01:31:24.950 --> 01:31:24.960 align:start position:0% and how we make smart contracts software 01:31:24.960 --> 01:31:28.910 align:start position:0% and how we make smart contracts software and<01:31:25.260> enable<01:31:25.760> historical<01:31:26.760> data<01:31:27.420> reads 01:31:28.910 --> 01:31:28.920 align:start position:0% and enable historical data reads 01:31:28.920 --> 01:31:30.830 align:start position:0% and enable historical data reads cool<01:31:29.580> so 01:31:30.830 --> 01:31:30.840 align:start position:0% cool so 01:31:30.840 --> 01:31:33.410 align:start position:0% cool so um 01:31:33.410 --> 01:31:33.420 align:start position:0% 01:31:33.420 --> 01:31:36.530 align:start position:0% it's<01:31:34.020> pretty<01:31:34.260> that's<01:31:34.980> pretty<01:31:35.280> tricky 01:31:36.530 --> 01:31:36.540 align:start position:0% it's pretty that's pretty tricky 01:31:36.540 --> 01:31:39.229 align:start position:0% it's pretty that's pretty tricky so<01:31:37.260> about<01:31:37.800> the<01:31:38.100> background<01:31:38.400> that<01:31:38.820> I<01:31:39.000> want<01:31:39.120> you 01:31:39.229 --> 01:31:39.239 align:start position:0% so about the background that I want you 01:31:39.239 --> 01:31:41.330 align:start position:0% so about the background that I want you to<01:31:39.480> have<01:31:39.659> for<01:31:39.960> this<01:31:40.080> Workshop<01:31:40.500> so<01:31:40.980> we're<01:31:41.159> gonna 01:31:41.330 --> 01:31:41.340 align:start position:0% to have for this Workshop so we're gonna 01:31:41.340 --> 01:31:44.570 align:start position:0% to have for this Workshop so we're gonna like<01:31:41.940> start<01:31:42.239> from<01:31:42.659> the<01:31:43.260> biggest<01:31:43.440> Basics<01:31:43.980> so 01:31:44.570 --> 01:31:44.580 align:start position:0% like start from the biggest Basics so 01:31:44.580 --> 01:31:46.250 align:start position:0% like start from the biggest Basics so what<01:31:44.760> is<01:31:44.880> the<01:31:45.000> hashing<01:31:45.300> function<01:31:45.600> just<01:31:45.900> a<01:31:46.139> very 01:31:46.250 --> 01:31:46.260 align:start position:0% what is the hashing function just a very 01:31:46.260 --> 01:31:48.350 align:start position:0% what is the hashing function just a very quick<01:31:46.440> reminder<01:31:46.739> I<01:31:47.580> hope<01:31:47.699> it<01:31:47.820> will<01:31:48.000> take<01:31:48.120> less 01:31:48.350 --> 01:31:48.360 align:start position:0% quick reminder I hope it will take less 01:31:48.360 --> 01:31:50.750 align:start position:0% quick reminder I hope it will take less than<01:31:48.540> a<01:31:48.659> minute<01:31:48.860> uh<01:31:49.860> like<01:31:50.159> generalized 01:31:50.750 --> 01:31:50.760 align:start position:0% than a minute uh like generalized 01:31:50.760 --> 01:31:53.390 align:start position:0% than a minute uh like generalized blockchain<01:31:51.060> Anatomy<01:31:51.659> how<01:31:52.320> I<01:31:52.500> ethereum<01:31:52.920> header 01:31:53.390 --> 01:31:53.400 align:start position:0% blockchain Anatomy how I ethereum header 01:31:53.400 --> 01:31:55.729 align:start position:0% blockchain Anatomy how I ethereum header looks<01:31:53.940> like<01:31:54.000> why<01:31:54.420> ethereum<01:31:54.840> they're<01:31:55.320> not<01:31:55.560> like 01:31:55.729 --> 01:31:55.739 align:start position:0% looks like why ethereum they're not like 01:31:55.739 --> 01:31:58.790 align:start position:0% looks like why ethereum they're not like pretty<01:31:56.100> on<01:31:56.699> only<01:31:57.120> like<01:31:57.360> ethereum<01:31:57.900> focused<01:31:58.260> uh 01:31:58.790 --> 01:31:58.800 align:start position:0% pretty on only like ethereum focused uh 01:31:58.800 --> 01:32:00.410 align:start position:0% pretty on only like ethereum focused uh however<01:31:59.100> I<01:31:59.460> think<01:31:59.580> that<01:31:59.760> for<01:31:59.940> the<01:32:00.060> sake<01:32:00.239> of 01:32:00.410 --> 01:32:00.420 align:start position:0% however I think that for the sake of 01:32:00.420 --> 01:32:01.790 align:start position:0% however I think that for the sake of this<01:32:00.600> Workshop<01:32:00.900> it's<01:32:01.199> the<01:32:01.440> best<01:32:01.560> to<01:32:01.679> like 01:32:01.790 --> 01:32:01.800 align:start position:0% this Workshop it's the best to like 01:32:01.800 --> 01:32:04.250 align:start position:0% this Workshop it's the best to like present<01:32:02.100> on<01:32:02.280> this<01:32:02.340> concrete<01:32:02.699> example<01:32:03.600> Miracle 01:32:04.250 --> 01:32:04.260 align:start position:0% present on this concrete example Miracle 01:32:04.260 --> 01:32:06.229 align:start position:0% present on this concrete example Miracle trees<01:32:04.620> explain<01:32:04.800> me<01:32:05.100> like<01:32:05.219> on<01:32:05.460> five<01:32:05.639> I<01:32:06.060> will 01:32:06.229 --> 01:32:06.239 align:start position:0% trees explain me like on five I will 01:32:06.239 --> 01:32:09.770 align:start position:0% trees explain me like on five I will just<01:32:06.480> quickly<01:32:07.460> explain<01:32:08.460> the<01:32:08.880> idea<01:32:09.179> how<01:32:09.600> it 01:32:09.770 --> 01:32:09.780 align:start position:0% just quickly explain the idea how it 01:32:09.780 --> 01:32:12.410 align:start position:0% just quickly explain the idea how it works<01:32:10.139> and<01:32:10.920> what<01:32:11.280> is<01:32:11.400> America<01:32:11.580> Patricia<01:32:12.239> tree 01:32:12.410 --> 01:32:12.420 align:start position:0% works and what is America Patricia tree 01:32:12.420 --> 01:32:13.790 align:start position:0% works and what is America Patricia tree without<01:32:12.780> really<01:32:13.139> going<01:32:13.320> too<01:32:13.500> much<01:32:13.620> into 01:32:13.790 --> 01:32:13.800 align:start position:0% without really going too much into 01:32:13.800 --> 01:32:15.590 align:start position:0% without really going too much into digitals 01:32:15.590 --> 01:32:15.600 align:start position:0% digitals 01:32:15.600 --> 01:32:19.669 align:start position:0% digitals um yeah<01:32:16.040> finally<01:32:17.040> no<01:32:18.000> not<01:32:18.239> finally<01:32:18.600> uh<01:32:19.500> the 01:32:19.669 --> 01:32:19.679 align:start position:0% um yeah finally no not finally uh the 01:32:19.679 --> 01:32:22.250 align:start position:0% um yeah finally no not finally uh the anatomy<01:32:20.159> the<01:32:20.340> ethereum<01:32:20.820> state 01:32:22.250 --> 01:32:22.260 align:start position:0% anatomy the ethereum state 01:32:22.260 --> 01:32:24.410 align:start position:0% anatomy the ethereum state it's<01:32:22.440> pretty<01:32:22.800> important<01:32:23.460> to<01:32:23.820> like<01:32:24.000> deal<01:32:24.179> with 01:32:24.410 --> 01:32:24.420 align:start position:0% it's pretty important to like deal with 01:32:24.420 --> 01:32:27.110 align:start position:0% it's pretty important to like deal with this<01:32:24.719> uh<01:32:25.020> with<01:32:25.739> this<01:32:25.920> primitive<01:32:26.340> and<01:32:26.760> finally 01:32:27.110 --> 01:32:27.120 align:start position:0% this uh with this primitive and finally 01:32:27.120 --> 01:32:29.930 align:start position:0% this uh with this primitive and finally how<01:32:27.480> to<01:32:27.600> deal<01:32:27.780> with<01:32:27.960> the<01:32:28.080> storage<01:32:28.260> layout 01:32:29.930 --> 01:32:29.940 align:start position:0% how to deal with the storage layout 01:32:29.940 --> 01:32:33.229 align:start position:0% how to deal with the storage layout cool<01:32:30.600> so<01:32:31.020> touching<01:32:31.800> function<01:32:32.100> essential<01:32:33.060> is 01:32:33.229 --> 01:32:33.239 align:start position:0% cool so touching function essential is 01:32:33.239 --> 01:32:34.910 align:start position:0% cool so touching function essential is this<01:32:33.420> idea 01:32:34.910 --> 01:32:34.920 align:start position:0% this idea 01:32:34.920 --> 01:32:37.070 align:start position:0% this idea essentially<01:32:35.639> it's<01:32:35.820> this<01:32:36.120> idea<01:32:36.420> that<01:32:36.659> I<01:32:36.960> can 01:32:37.070 --> 01:32:37.080 align:start position:0% essentially it's this idea that I can 01:32:37.080 --> 01:32:39.770 align:start position:0% essentially it's this idea that I can have<01:32:37.320> a<01:32:37.800> function<01:32:38.219> that<01:32:38.580> takes<01:32:38.699> some<01:32:38.940> input 01:32:39.770 --> 01:32:39.780 align:start position:0% have a function that takes some input 01:32:39.780 --> 01:32:42.490 align:start position:0% have a function that takes some input of<01:32:40.380> any<01:32:40.560> size<01:32:40.800> and<01:32:41.219> it<01:32:41.400> always<01:32:41.639> always<01:32:42.120> return 01:32:42.490 --> 01:32:42.500 align:start position:0% of any size and it always always return 01:32:42.500 --> 01:32:45.290 align:start position:0% of any size and it always always return an<01:32:43.500> output<01:32:43.800> of<01:32:44.040> a<01:32:44.159> fixed<01:32:44.460> size<01:32:44.580> and<01:32:44.880> now<01:32:45.060> what's 01:32:45.290 --> 01:32:45.300 align:start position:0% an output of a fixed size and now what's 01:32:45.300 --> 01:32:48.590 align:start position:0% an output of a fixed size and now what's also<01:32:45.659> important<01:32:46.040> there<01:32:47.040> is<01:32:47.219> no<01:32:47.580> input<01:32:48.000> there 01:32:48.590 --> 01:32:48.600 align:start position:0% also important there is no input there 01:32:48.600 --> 01:32:50.149 align:start position:0% also important there is no input there are<01:32:48.780> no<01:32:48.840> two<01:32:49.020> inputs<01:32:49.380> that<01:32:49.500> will<01:32:49.620> generate<01:32:49.980> the 01:32:50.149 --> 01:32:50.159 align:start position:0% are no two inputs that will generate the 01:32:50.159 --> 01:32:53.510 align:start position:0% are no two inputs that will generate the same<01:32:50.340> output<01:32:50.699> and<01:32:51.600> you<01:32:51.840> cannot<01:32:52.139> reverse<01:32:52.620> the 01:32:53.510 --> 01:32:53.520 align:start position:0% same output and you cannot reverse the 01:32:53.520 --> 01:32:55.129 align:start position:0% same output and you cannot reverse the hashing<01:32:53.880> function<01:32:54.179> so<01:32:54.360> it<01:32:54.480> means<01:32:54.659> that<01:32:54.780> given 01:32:55.129 --> 01:32:55.139 align:start position:0% hashing function so it means that given 01:32:55.139 --> 01:32:56.510 align:start position:0% hashing function so it means that given the<01:32:55.260> output<01:32:55.500> you<01:32:55.739> don't<01:32:55.920> know<01:32:56.040> what<01:32:56.219> is<01:32:56.340> the 01:32:56.510 --> 01:32:56.520 align:start position:0% the output you don't know what is the 01:32:56.520 --> 01:32:58.430 align:start position:0% the output you don't know what is the input<01:32:56.820> and<01:32:57.300> this<01:32:57.420> is<01:32:57.540> not<01:32:57.719> what<01:32:57.960> we<01:32:58.080> call<01:32:58.199> like 01:32:58.430 --> 01:32:58.440 align:start position:0% input and this is not what we call like 01:32:58.440 --> 01:33:00.470 align:start position:0% input and this is not what we call like Collision<01:32:58.800> resistance<01:32:59.460> pretty<01:33:00.179> useful 01:33:00.470 --> 01:33:00.480 align:start position:0% Collision resistance pretty useful 01:33:00.480 --> 01:33:02.570 align:start position:0% Collision resistance pretty useful primitive<01:33:00.840> like<01:33:01.020> used<01:33:01.199> in<01:33:01.380> blockchains<01:33:01.980> uh<01:33:02.340> I 01:33:02.570 --> 01:33:02.580 align:start position:0% primitive like used in blockchains uh I 01:33:02.580 --> 01:33:04.070 align:start position:0% primitive like used in blockchains uh I will<01:33:02.760> and<01:33:03.120> I<01:33:03.300> think<01:33:03.420> that's<01:33:03.600> that's<01:33:03.900> pretty 01:33:04.070 --> 01:33:04.080 align:start position:0% will and I think that's that's pretty 01:33:04.080 --> 01:33:05.510 align:start position:0% will and I think that's that's pretty much<01:33:04.199> what<01:33:04.380> I<01:33:04.560> assume<01:33:04.860> that<01:33:04.980> everyone<01:33:05.100> is<01:33:05.340> like 01:33:05.510 --> 01:33:05.520 align:start position:0% much what I assume that everyone is like 01:33:05.520 --> 01:33:08.810 align:start position:0% much what I assume that everyone is like familiar<01:33:06.000> with<01:33:06.239> like<01:33:06.659> yeah<01:33:07.080> okay<01:33:07.980> why<01:33:08.580> is<01:33:08.699> it 01:33:08.810 --> 01:33:08.820 align:start position:0% familiar with like yeah okay why is it 01:33:08.820 --> 01:33:12.229 align:start position:0% familiar with like yeah okay why is it important 01:33:12.229 --> 01:33:12.239 align:start position:0% 01:33:12.239 --> 01:33:14.590 align:start position:0% um<01:33:12.300> so<01:33:12.659> generalized<01:33:13.380> blockchain 01:33:14.590 --> 01:33:14.600 align:start position:0% um so generalized blockchain 01:33:14.600 --> 01:33:16.850 align:start position:0% um so generalized blockchain Anatomy<01:33:15.600> so<01:33:15.780> why<01:33:16.020> we<01:33:16.199> call<01:33:16.320> it<01:33:16.500> a<01:33:16.679> chain 01:33:16.850 --> 01:33:16.860 align:start position:0% Anatomy so why we call it a chain 01:33:16.860 --> 01:33:19.729 align:start position:0% Anatomy so why we call it a chain because<01:33:17.280> we<01:33:17.639> have<01:33:18.000> a<01:33:18.300> bunch<01:33:18.659> of<01:33:18.780> blocks<01:33:19.199> mined 01:33:19.729 --> 01:33:19.739 align:start position:0% because we have a bunch of blocks mined 01:33:19.739 --> 01:33:22.129 align:start position:0% because we have a bunch of blocks mined together<01:33:19.860> like<01:33:20.400> linked<01:33:21.120> together<01:33:21.239> because 01:33:22.129 --> 01:33:22.139 align:start position:0% together like linked together because 01:33:22.139 --> 01:33:24.530 align:start position:0% together like linked together because each<01:33:22.860> block<01:33:23.100> contains<01:33:23.699> the<01:33:24.000> reference<01:33:24.360> the 01:33:24.530 --> 01:33:24.540 align:start position:0% each block contains the reference the 01:33:24.540 --> 01:33:27.169 align:start position:0% each block contains the reference the parent<01:33:24.719> hash<01:33:25.280> and<01:33:26.280> the<01:33:26.580> previous<01:33:26.699> header 01:33:27.169 --> 01:33:27.179 align:start position:0% parent hash and the previous header 01:33:27.179 --> 01:33:28.310 align:start position:0% parent hash and the previous header contains<01:33:27.600> the<01:33:27.719> reference<01:33:27.960> of<01:33:28.080> the<01:33:28.199> parent 01:33:28.310 --> 01:33:28.320 align:start position:0% contains the reference of the parent 01:33:28.320 --> 01:33:30.590 align:start position:0% contains the reference of the parent hash<01:33:28.739> which<01:33:29.219> is<01:33:29.340> pretty<01:33:29.520> cool<01:33:29.760> and<01:33:29.940> let<01:33:30.420> me 01:33:30.590 --> 01:33:30.600 align:start position:0% hash which is pretty cool and let me 01:33:30.600 --> 01:33:32.930 align:start position:0% hash which is pretty cool and let me remind<01:33:30.719> what<01:33:31.020> the<01:33:31.260> hash<01:33:31.620> the<01:33:32.159> parent<01:33:32.520> hash<01:33:32.820> or 01:33:32.930 --> 01:33:32.940 align:start position:0% remind what the hash the parent hash or 01:33:32.940 --> 01:33:35.870 align:start position:0% remind what the hash the parent hash or the<01:33:33.060> block<01:33:33.239> hash<01:33:33.600> of<01:33:34.440> uh<01:33:34.920> on<01:33:35.159> ethereum<01:33:35.520> is<01:33:35.760> it's 01:33:35.870 --> 01:33:35.880 align:start position:0% the block hash of uh on ethereum is it's 01:33:35.880 --> 01:33:38.390 align:start position:0% the block hash of uh on ethereum is it's essentially<01:33:36.179> the<01:33:36.360> hash<01:33:36.600> of<01:33:36.719> the<01:33:36.840> header<01:33:37.560> uh 01:33:38.390 --> 01:33:38.400 align:start position:0% essentially the hash of the header uh 01:33:38.400 --> 01:33:40.490 align:start position:0% essentially the hash of the header uh pretty<01:33:38.639> important<01:33:39.120> to<01:33:39.659> deal<01:33:39.900> with<01:33:40.260> this 01:33:40.490 --> 01:33:40.500 align:start position:0% pretty important to deal with this 01:33:40.500 --> 01:33:42.229 align:start position:0% pretty important to deal with this Primitives<01:33:41.040> and<01:33:41.340> make<01:33:41.520> smart<01:33:41.760> contracts 01:33:42.229 --> 01:33:42.239 align:start position:0% Primitives and make smart contracts 01:33:42.239 --> 01:33:44.830 align:start position:0% Primitives and make smart contracts software<01:33:42.600> so<01:33:42.900> accessing<01:33:43.380> six<01:33:43.560> Oracle<01:33:43.980> state 01:33:44.830 --> 01:33:44.840 align:start position:0% software so accessing six Oracle state 01:33:44.840 --> 01:33:47.930 align:start position:0% software so accessing six Oracle state do<01:33:45.840> you<01:33:46.020> just<01:33:46.260> keep<01:33:46.440> that<01:33:46.620> in<01:33:46.739> mind 01:33:47.930 --> 01:33:47.940 align:start position:0% do you just keep that in mind 01:33:47.940 --> 01:33:51.830 align:start position:0% do you just keep that in mind let's<01:33:48.719> get<01:33:49.139> to<01:33:49.320> the<01:33:49.500> next<01:33:49.679> part<01:33:49.980> so 01:33:51.830 --> 01:33:51.840 align:start position:0% let's get to the next part so 01:33:51.840 --> 01:33:54.649 align:start position:0% let's get to the next part so um no 01:33:54.649 --> 01:33:54.659 align:start position:0% 01:33:54.659 --> 01:33:58.790 align:start position:0% ah<01:33:55.380> I<01:33:56.280> think<01:33:56.400> I'm<01:33:56.699> missing<01:33:57.179> one<01:33:57.780> slide 01:33:58.790 --> 01:33:58.800 align:start position:0% ah I think I'm missing one slide 01:33:58.800 --> 01:34:02.930 align:start position:0% ah I think I'm missing one slide no<01:33:59.340> it's<01:33:59.699> the<01:33:59.940> correct<01:34:00.239> one<01:34:00.900> okay<01:34:01.679> so<01:34:02.219> uh<01:34:02.760> this 01:34:02.930 --> 01:34:02.940 align:start position:0% no it's the correct one okay so uh this 01:34:02.940 --> 01:34:04.910 align:start position:0% no it's the correct one okay so uh this is<01:34:03.060> an<01:34:03.120> ethereum<01:34:03.480> block<01:34:03.659> header<01:34:04.080> uh<01:34:04.500> as<01:34:04.620> I<01:34:04.739> said 01:34:04.910 --> 01:34:04.920 align:start position:0% is an ethereum block header uh as I said 01:34:04.920 --> 01:34:06.649 align:start position:0% is an ethereum block header uh as I said we're<01:34:05.100> gonna<01:34:05.219> go<01:34:05.520> through<01:34:05.699> the<01:34:05.940> example<01:34:06.420> of 01:34:06.649 --> 01:34:06.659 align:start position:0% we're gonna go through the example of 01:34:06.659 --> 01:34:09.830 align:start position:0% we're gonna go through the example of ethereum<01:34:07.260> concretely<01:34:07.739> so<01:34:08.580> a<01:34:09.060> bit<01:34:09.179> of<01:34:09.300> anatomy 01:34:09.830 --> 01:34:09.840 align:start position:0% ethereum concretely so a bit of anatomy 01:34:09.840 --> 01:34:12.290 align:start position:0% ethereum concretely so a bit of anatomy so<01:34:10.500> to<01:34:10.800> access<01:34:10.980> State<01:34:11.340> obviously<01:34:11.760> we<01:34:11.880> need<01:34:12.060> the 01:34:12.290 --> 01:34:12.300 align:start position:0% so to access State obviously we need the 01:34:12.300 --> 01:34:13.850 align:start position:0% so to access State obviously we need the state<01:34:12.540> route<01:34:12.780> what<01:34:13.020> is<01:34:13.139> the<01:34:13.260> state<01:34:13.380> route<01:34:13.620> is 01:34:13.850 --> 01:34:13.860 align:start position:0% state route what is the state route is 01:34:13.860 --> 01:34:16.610 align:start position:0% state route what is the state route is the<01:34:13.980> root<01:34:14.340> of<01:34:14.460> the<01:34:14.520> miracle<01:34:14.940> Patricia<01:34:15.420> tree<01:34:15.659> of 01:34:16.610 --> 01:34:16.620 align:start position:0% the root of the miracle Patricia tree of 01:34:16.620 --> 01:34:17.930 align:start position:0% the root of the miracle Patricia tree of the<01:34:16.800> ethereum<01:34:17.100> state 01:34:17.930 --> 01:34:17.940 align:start position:0% the ethereum state 01:34:17.940 --> 01:34:19.850 align:start position:0% the ethereum state we<01:34:18.420> also<01:34:18.780> have<01:34:18.840> the<01:34:18.960> transactions<01:34:19.380> rule<01:34:19.679> which 01:34:19.850 --> 01:34:19.860 align:start position:0% we also have the transactions rule which 01:34:19.860 --> 01:34:21.770 align:start position:0% we also have the transactions rule which is<01:34:19.920> pretty<01:34:20.040> useful<01:34:20.400> if<01:34:20.639> you<01:34:20.760> want<01:34:21.000> to<01:34:21.179> access 01:34:21.770 --> 01:34:21.780 align:start position:0% is pretty useful if you want to access 01:34:21.780 --> 01:34:23.450 align:start position:0% is pretty useful if you want to access historical<01:34:22.440> transactions<01:34:23.040> like<01:34:23.219> their 01:34:23.450 --> 01:34:23.460 align:start position:0% historical transactions like their 01:34:23.460 --> 01:34:26.330 align:start position:0% historical transactions like their entire<01:34:23.760> body<01:34:24.380> and<01:34:25.380> receive<01:34:25.739> truth<01:34:26.040> so<01:34:26.219> it's 01:34:26.330 --> 01:34:26.340 align:start position:0% entire body and receive truth so it's 01:34:26.340 --> 01:34:29.570 align:start position:0% entire body and receive truth so it's really<01:34:26.580> useful<01:34:26.880> to<01:34:27.179> access<01:34:27.440> any<01:34:28.440> events<01:34:28.860> logs 01:34:29.570 --> 01:34:29.580 align:start position:0% really useful to access any events logs 01:34:29.580 --> 01:34:32.090 align:start position:0% really useful to access any events logs and<01:34:29.880> and<01:34:30.300> so<01:34:30.540> on<01:34:30.659> and<01:34:31.139> all<01:34:31.380> of<01:34:31.500> these<01:34:31.739> are<01:34:31.920> like 01:34:32.090 --> 01:34:32.100 align:start position:0% and and so on and all of these are like 01:34:32.100 --> 01:34:34.370 align:start position:0% and and so on and all of these are like root<01:34:32.639> of<01:34:32.760> the<01:34:32.820> American<01:34:32.940> Patricia<01:34:33.600> tree 01:34:34.370 --> 01:34:34.380 align:start position:0% root of the American Patricia tree 01:34:34.380 --> 01:34:37.010 align:start position:0% root of the American Patricia tree America<01:34:34.679> Patricia<01:34:35.340> 3's<01:34:35.760> America<01:34:36.420> 3<01:34:36.780> just 01:34:37.010 --> 01:34:37.020 align:start position:0% America Patricia 3's America 3 just 01:34:37.020 --> 01:34:39.350 align:start position:0% America Patricia 3's America 3 just think<01:34:37.139> of<01:34:37.320> it<01:34:37.440> in<01:34:37.620> that<01:34:37.739> way<01:34:38.280> and<01:34:39.179> most 01:34:39.350 --> 01:34:39.360 align:start position:0% think of it in that way and most 01:34:39.360 --> 01:34:41.510 align:start position:0% think of it in that way and most importantly<01:34:39.780> we<01:34:40.380> have<01:34:40.440> the<01:34:40.560> parent<01:34:40.739> hash<01:34:41.159> and 01:34:41.510 --> 01:34:41.520 align:start position:0% importantly we have the parent hash and 01:34:41.520 --> 01:34:43.729 align:start position:0% importantly we have the parent hash and with<01:34:41.699> the<01:34:41.820> parent<01:34:41.940> hash<01:34:42.360> we<01:34:42.659> can<01:34:42.900> in<01:34:43.199> a<01:34:43.320> way<01:34:43.440> go 01:34:43.729 --> 01:34:43.739 align:start position:0% with the parent hash we can in a way go 01:34:43.739 --> 01:34:48.050 align:start position:0% with the parent hash we can in a way go go<01:34:44.040> backwards<01:34:45.120> I<01:34:45.840> think<01:34:46.080> that's<01:34:46.560> it<01:34:47.400> let's<01:34:47.820> get 01:34:48.050 --> 01:34:48.060 align:start position:0% go backwards I think that's it let's get 01:34:48.060 --> 01:34:50.149 align:start position:0% go backwards I think that's it let's get to<01:34:48.360> Miracle<01:34:49.020> tree<01:34:49.139> so<01:34:49.380> essentially<01:34:49.739> it's<01:34:49.920> this 01:34:50.149 --> 01:34:50.159 align:start position:0% to Miracle tree so essentially it's this 01:34:50.159 --> 01:34:52.910 align:start position:0% to Miracle tree so essentially it's this idea<01:34:50.520> that<01:34:51.120> I<01:34:51.360> can<01:34:51.540> take<01:34:52.139> whatever<01:34:52.380> amount<01:34:52.800> of 01:34:52.910 --> 01:34:52.920 align:start position:0% idea that I can take whatever amount of 01:34:52.920 --> 01:34:55.189 align:start position:0% idea that I can take whatever amount of data<01:34:53.340> and<01:34:54.060> I<01:34:54.179> can<01:34:54.360> commit<01:34:54.840> it<01:34:54.900> in<01:34:55.080> a 01:34:55.189 --> 01:34:55.199 align:start position:0% data and I can commit it in a 01:34:55.199 --> 01:34:58.189 align:start position:0% data and I can commit it in a cryptographic<01:34:55.739> manner<01:34:56.040> by<01:34:56.820> using<01:34:57.300> this<01:34:57.840> data 01:34:58.189 --> 01:34:58.199 align:start position:0% cryptographic manner by using this data 01:34:58.199 --> 01:35:00.590 align:start position:0% cryptographic manner by using this data structure<01:34:58.620> so<01:34:59.400> on<01:34:59.820> the 01:35:00.590 --> 01:35:00.600 align:start position:0% structure so on the 01:35:00.600 --> 01:35:03.229 align:start position:0% structure so on the left<01:35:01.260> side<01:35:01.500> we<01:35:02.040> see<01:35:02.159> a<01:35:02.400> standard<01:35:02.699> Merkle<01:35:03.060> tree 01:35:03.229 --> 01:35:03.239 align:start position:0% left side we see a standard Merkle tree 01:35:03.239 --> 01:35:05.030 align:start position:0% left side we see a standard Merkle tree so<01:35:03.659> essentially<01:35:03.960> all<01:35:04.320> the<01:35:04.440> data<01:35:04.620> goes<01:35:04.860> to<01:35:04.920> the 01:35:05.030 --> 01:35:05.040 align:start position:0% so essentially all the data goes to the 01:35:05.040 --> 01:35:07.010 align:start position:0% so essentially all the data goes to the bottom<01:35:05.280> and<01:35:05.460> we<01:35:05.639> essentially<01:35:06.000> hash<01:35:06.300> it<01:35:06.480> you 01:35:07.010 --> 01:35:07.020 align:start position:0% bottom and we essentially hash it you 01:35:07.020 --> 01:35:08.209 align:start position:0% bottom and we essentially hash it you know<01:35:07.139> what<01:35:07.199> the<01:35:07.380> hashing<01:35:07.679> function<01:35:07.920> is<01:35:07.980> then 01:35:08.209 --> 01:35:08.219 align:start position:0% know what the hashing function is then 01:35:08.219 --> 01:35:09.290 align:start position:0% know what the hashing function is then we<01:35:08.400> combine<01:35:08.580> these<01:35:08.760> two<01:35:08.820> hashes<01:35:09.179> together 01:35:09.290 --> 01:35:09.300 align:start position:0% we combine these two hashes together 01:35:09.300 --> 01:35:12.709 align:start position:0% we combine these two hashes together with<01:35:09.600> hashtag<01:35:10.080> we<01:35:10.800> keep<01:35:10.980> doing<01:35:11.159> that<01:35:11.400> until<01:35:11.719> we 01:35:12.709 --> 01:35:12.719 align:start position:0% with hashtag we keep doing that until we 01:35:12.719 --> 01:35:14.149 align:start position:0% with hashtag we keep doing that until we get<01:35:12.840> to<01:35:12.960> essentially<01:35:13.320> one<01:35:13.500> hush<01:35:13.800> and<01:35:13.980> this<01:35:14.100> is 01:35:14.149 --> 01:35:14.159 align:start position:0% get to essentially one hush and this is 01:35:14.159 --> 01:35:16.310 align:start position:0% get to essentially one hush and this is what<01:35:14.280> we<01:35:14.400> call<01:35:14.460> the<01:35:14.639> root<01:35:15.420> mark<01:35:15.780> up<01:35:16.020> to<01:35:16.199> three 01:35:16.310 --> 01:35:16.320 align:start position:0% what we call the root mark up to three 01:35:16.320 --> 01:35:18.169 align:start position:0% what we call the root mark up to three shot<01:35:16.500> three<01:35:16.679> modified<01:35:17.280> Miracle<01:35:17.699> Patricia<01:35:18.060> 2 01:35:18.169 --> 01:35:18.179 align:start position:0% shot three modified Miracle Patricia 2 01:35:18.179 --> 01:35:21.290 align:start position:0% shot three modified Miracle Patricia 2 to<01:35:18.420> be<01:35:18.540> exactly<01:35:19.219> the<01:35:20.219> data<01:35:20.520> structure<01:35:21.060> that<01:35:21.179> we 01:35:21.290 --> 01:35:21.300 align:start position:0% to be exactly the data structure that we 01:35:21.300 --> 01:35:23.030 align:start position:0% to be exactly the data structure that we use<01:35:21.480> in<01:35:21.659> ethereum 01:35:23.030 --> 01:35:23.040 align:start position:0% use in ethereum 01:35:23.040 --> 01:35:26.270 align:start position:0% use in ethereum um<01:35:23.159> what<01:35:23.820> you<01:35:23.940> see<01:35:24.060> here<01:35:24.300> I<01:35:24.900> hope<01:35:25.139> you<01:35:25.320> see<01:35:25.560> on 01:35:26.270 --> 01:35:26.280 align:start position:0% um what you see here I hope you see on 01:35:26.280 --> 01:35:28.070 align:start position:0% um what you see here I hope you see on the<01:35:26.400> top<01:35:26.460> we<01:35:26.639> have<01:35:26.760> the<01:35:26.880> state<01:35:27.060> route 01:35:28.070 --> 01:35:28.080 align:start position:0% the top we have the state route 01:35:28.080 --> 01:35:30.050 align:start position:0% the top we have the state route and<01:35:28.620> essentially<01:35:29.040> the<01:35:29.280> state<01:35:29.460> route<01:35:29.699> is<01:35:29.880> the 01:35:30.050 --> 01:35:30.060 align:start position:0% and essentially the state route is the 01:35:30.060 --> 01:35:31.970 align:start position:0% and essentially the state route is the root<01:35:30.480> of<01:35:30.540> this<01:35:30.719> tree<01:35:30.960> and<01:35:31.320> now<01:35:31.440> how<01:35:31.620> it<01:35:31.739> works 01:35:31.970 --> 01:35:31.980 align:start position:0% root of this tree and now how it works 01:35:31.980 --> 01:35:33.830 align:start position:0% root of this tree and now how it works and<01:35:32.100> how<01:35:32.340> you<01:35:32.460> should<01:35:32.580> think<01:35:32.760> of<01:35:32.940> this<01:35:33.179> of<01:35:33.600> this 01:35:33.830 --> 01:35:33.840 align:start position:0% and how you should think of this of this 01:35:33.840 --> 01:35:36.050 align:start position:0% and how you should think of this of this it's<01:35:34.080> a<01:35:34.320> pretty<01:35:34.500> complex<01:35:35.040> data<01:35:35.520> structure<01:35:35.820> I 01:35:36.050 --> 01:35:36.060 align:start position:0% it's a pretty complex data structure I 01:35:36.060 --> 01:35:37.570 align:start position:0% it's a pretty complex data structure I don't<01:35:36.179> want<01:35:36.300> you<01:35:36.420> to<01:35:36.540> bother<01:35:36.780> with<01:35:37.080> it<01:35:37.320> today 01:35:37.570 --> 01:35:37.580 align:start position:0% don't want you to bother with it today 01:35:37.580 --> 01:35:41.330 align:start position:0% don't want you to bother with it today but<01:35:38.580> essentially<01:35:39.260> we<01:35:40.260> have<01:35:40.440> three<01:35:40.800> types<01:35:41.159> of 01:35:41.330 --> 01:35:41.340 align:start position:0% but essentially we have three types of 01:35:41.340 --> 01:35:44.270 align:start position:0% but essentially we have three types of like<01:35:41.699> notes<01:35:42.120> we<01:35:42.420> have<01:35:42.600> Leaf<01:35:43.560> nodes<01:35:43.800> extension 01:35:44.270 --> 01:35:44.280 align:start position:0% like notes we have Leaf nodes extension 01:35:44.280 --> 01:35:47.629 align:start position:0% like notes we have Leaf nodes extension notes<01:35:44.760> and<01:35:45.060> Branch<01:35:45.480> notes<01:35:45.960> so<01:35:46.800> Leaf<01:35:47.460> nodes 01:35:47.629 --> 01:35:47.639 align:start position:0% notes and Branch notes so Leaf nodes 01:35:47.639 --> 01:35:49.850 align:start position:0% notes and Branch notes so Leaf nodes contain<01:35:48.000> data<01:35:48.360> Branch<01:35:48.719> nodes<01:35:49.020> contain<01:35:49.380> data 01:35:49.850 --> 01:35:49.860 align:start position:0% contain data Branch nodes contain data 01:35:49.860 --> 01:35:52.189 align:start position:0% contain data Branch nodes contain data and<01:35:50.580> extension<01:35:51.120> nodes<01:35:51.420> like<01:35:51.780> on<01:35:51.960> the<01:35:52.080> high 01:35:52.189 --> 01:35:52.199 align:start position:0% and extension nodes like on the high 01:35:52.199 --> 01:35:53.870 align:start position:0% and extension nodes like on the high level<01:35:52.380> just<01:35:52.860> help<01:35:53.100> us<01:35:53.280> to<01:35:53.460> like<01:35:53.580> sort<01:35:53.760> of 01:35:53.870 --> 01:35:53.880 align:start position:0% level just help us to like sort of 01:35:53.880 --> 01:35:56.030 align:start position:0% level just help us to like sort of navigate<01:35:54.120> in<01:35:54.540> that<01:35:54.719> tree<01:35:54.900> but<01:35:55.560> to<01:35:55.679> be<01:35:55.800> honest 01:35:56.030 --> 01:35:56.040 align:start position:0% navigate in that tree but to be honest 01:35:56.040 --> 01:35:57.890 align:start position:0% navigate in that tree but to be honest to<01:35:56.760> deal<01:35:56.820> with<01:35:57.000> storage<01:35:57.179> truth<01:35:57.600> you<01:35:57.780> don't 01:35:57.890 --> 01:35:57.900 align:start position:0% to deal with storage truth you don't 01:35:57.900 --> 01:35:59.750 align:start position:0% to deal with storage truth you don't really<01:35:58.020> need<01:35:58.320> to<01:35:58.440> understand<01:35:58.620> this<01:35:59.100> part<01:35:59.280> but 01:35:59.750 --> 01:35:59.760 align:start position:0% really need to understand this part but 01:35:59.760 --> 01:36:02.149 align:start position:0% really need to understand this part but to<01:36:00.000> like<01:36:00.179> build<01:36:00.600> on<01:36:01.080> the<01:36:01.139> low<01:36:01.260> level<01:36:01.500> as<01:36:01.800> we<01:36:01.980> do 01:36:02.149 --> 01:36:02.159 align:start position:0% to like build on the low level as we do 01:36:02.159 --> 01:36:04.610 align:start position:0% to like build on the low level as we do obviously<01:36:02.940> we<01:36:03.060> need<01:36:03.239> to<01:36:03.480> we<01:36:04.199> need<01:36:04.380> to<01:36:04.440> do 01:36:04.610 --> 01:36:04.620 align:start position:0% obviously we need to we need to do 01:36:04.620 --> 01:36:07.070 align:start position:0% obviously we need to we need to do pretty<01:36:05.100> pretty<01:36:05.760> a<01:36:06.000> lot<01:36:06.120> with<01:36:06.300> that<01:36:06.480> with<01:36:06.719> that 01:36:07.070 --> 01:36:07.080 align:start position:0% pretty pretty a lot with that with that 01:36:07.080 --> 01:36:07.850 align:start position:0% pretty pretty a lot with that with that part 01:36:07.850 --> 01:36:07.860 align:start position:0% part 01:36:07.860 --> 01:36:09.050 align:start position:0% part okay 01:36:09.050 --> 01:36:09.060 align:start position:0% okay 01:36:09.060 --> 01:36:12.169 align:start position:0% okay so<01:36:09.780> ethereum<01:36:10.320> State<01:36:10.560> how<01:36:11.460> is<01:36:11.580> it<01:36:11.699> constructed 01:36:12.169 --> 01:36:12.179 align:start position:0% so ethereum State how is it constructed 01:36:12.179 --> 01:36:14.390 align:start position:0% so ethereum State how is it constructed most<01:36:13.020> important<01:36:13.320> takeaway<01:36:13.679> it's<01:36:13.920> a<01:36:14.100> two<01:36:14.219> level 01:36:14.390 --> 01:36:14.400 align:start position:0% most important takeaway it's a two level 01:36:14.400 --> 01:36:16.550 align:start position:0% most important takeaway it's a two level structure<01:36:14.940> so<01:36:15.659> I<01:36:15.840> mentioned<01:36:16.080> that<01:36:16.260> the<01:36:16.440> state 01:36:16.550 --> 01:36:16.560 align:start position:0% structure so I mentioned that the state 01:36:16.560 --> 01:36:18.229 align:start position:0% structure so I mentioned that the state route<01:36:16.860> is<01:36:17.100> the<01:36:17.400> commitment<01:36:17.699> of<01:36:17.940> the<01:36:18.000> entire 01:36:18.229 --> 01:36:18.239 align:start position:0% route is the commitment of the entire 01:36:18.239 --> 01:36:20.090 align:start position:0% route is the commitment of the entire state<01:36:18.540> but<01:36:19.020> it's<01:36:19.199> not<01:36:19.320> really<01:36:19.500> true<01:36:19.800> because 01:36:20.090 --> 01:36:20.100 align:start position:0% state but it's not really true because 01:36:20.100 --> 01:36:22.129 align:start position:0% state but it's not really true because ethereum<01:36:20.940> is<01:36:21.060> a 01:36:22.129 --> 01:36:22.139 align:start position:0% ethereum is a 01:36:22.139 --> 01:36:25.250 align:start position:0% ethereum is a does<01:36:22.560> it<01:36:22.739> still<01:36:22.860> okay<01:36:23.219> it<01:36:23.400> works<01:36:23.840> it's<01:36:24.840> uh<01:36:25.020> it's 01:36:25.250 --> 01:36:25.260 align:start position:0% does it still okay it works it's uh it's 01:36:25.260 --> 01:36:26.570 align:start position:0% does it still okay it works it's uh it's account<01:36:25.440> based 01:36:26.570 --> 01:36:26.580 align:start position:0% account based 01:36:26.580 --> 01:36:28.189 align:start position:0% account based um<01:36:26.699> and<01:36:27.000> essentially<01:36:27.360> the<01:36:27.540> state<01:36:27.659> route<01:36:27.960> is 01:36:28.189 --> 01:36:28.199 align:start position:0% um and essentially the state route is 01:36:28.199 --> 01:36:30.530 align:start position:0% um and essentially the state route is the<01:36:28.500> commitment<01:36:29.400> of<01:36:29.699> all<01:36:29.940> the<01:36:30.060> accounts<01:36:30.420> that 01:36:30.530 --> 01:36:30.540 align:start position:0% the commitment of all the accounts that 01:36:30.540 --> 01:36:32.689 align:start position:0% the commitment of all the accounts that exist<01:36:30.780> on<01:36:30.960> ethereum<01:36:31.380> and<01:36:31.920> what<01:36:32.100> an<01:36:32.280> account<01:36:32.400> is 01:36:32.689 --> 01:36:32.699 align:start position:0% exist on ethereum and what an account is 01:36:32.699 --> 01:36:34.550 align:start position:0% exist on ethereum and what an account is made<01:36:32.880> of<01:36:33.000> it's<01:36:33.179> made<01:36:33.360> of<01:36:33.540> a<01:36:33.659> balance 01:36:34.550 --> 01:36:34.560 align:start position:0% made of it's made of a balance 01:36:34.560 --> 01:36:36.770 align:start position:0% made of it's made of a balance like<01:36:35.100> the<01:36:35.219> if<01:36:35.400> balance<01:36:35.820> it's<01:36:36.300> announced 01:36:36.770 --> 01:36:36.780 align:start position:0% like the if balance it's announced 01:36:36.780 --> 01:36:40.129 align:start position:0% like the if balance it's announced transaction<01:36:37.620> counter<01:36:38.280> storage<01:36:39.000> route<01:36:39.420> the 01:36:40.129 --> 01:36:40.139 align:start position:0% transaction counter storage route the 01:36:40.139 --> 01:36:42.290 align:start position:0% transaction counter storage route the storage<01:36:40.320> route<01:36:40.620> is<01:36:41.100> like<01:36:41.580> the<01:36:41.820> root<01:36:42.120> of 01:36:42.290 --> 01:36:42.300 align:start position:0% storage route is like the root of 01:36:42.300 --> 01:36:44.330 align:start position:0% storage route is like the root of another<01:36:42.420> America<01:36:42.780> Patricia<01:36:43.440> tree<01:36:43.679> and<01:36:44.219> this 01:36:44.330 --> 01:36:44.340 align:start position:0% another America Patricia tree and this 01:36:44.340 --> 01:36:46.910 align:start position:0% another America Patricia tree and this America<01:36:44.520> Patricia<01:36:45.120> 3<01:36:45.420> contains<01:36:45.960> the<01:36:46.139> key 01:36:46.910 --> 01:36:46.920 align:start position:0% America Patricia 3 contains the key 01:36:46.920 --> 01:36:49.850 align:start position:0% America Patricia 3 contains the key value<01:36:47.219> database<01:36:47.880> that<01:36:48.600> holds<01:36:49.199> like 01:36:49.850 --> 01:36:49.860 align:start position:0% value database that holds like 01:36:49.860 --> 01:36:52.610 align:start position:0% value database that holds like the<01:36:50.340> mapping<01:36:50.880> from<01:36:51.239> storage<01:36:51.600> key<01:36:51.960> to<01:36:52.260> its 01:36:52.610 --> 01:36:52.620 align:start position:0% the mapping from storage key to its 01:36:52.620 --> 01:36:54.169 align:start position:0% the mapping from storage key to its actual<01:36:52.860> value 01:36:54.169 --> 01:36:54.179 align:start position:0% actual value 01:36:54.179 --> 01:36:56.270 align:start position:0% actual value and<01:36:54.659> finally<01:36:54.900> we<01:36:55.080> have<01:36:55.199> the<01:36:55.380> code<01:36:55.440> it's 01:36:56.270 --> 01:36:56.280 align:start position:0% and finally we have the code it's 01:36:56.280 --> 01:36:58.250 align:start position:0% and finally we have the code it's essentially<01:36:57.000> the<01:36:57.179> hash<01:36:57.420> of<01:36:57.600> the<01:36:57.719> of<01:36:58.080> the 01:36:58.250 --> 01:36:58.260 align:start position:0% essentially the hash of the of the 01:36:58.260 --> 01:36:59.209 align:start position:0% essentially the hash of the of the bytecode 01:36:59.209 --> 01:36:59.219 align:start position:0% bytecode 01:36:59.219 --> 01:37:01.729 align:start position:0% bytecode so<01:36:59.820> main<01:37:00.179> takeaway<01:37:00.600> first<01:37:01.139> we<01:37:01.500> access 01:37:01.729 --> 01:37:01.739 align:start position:0% so main takeaway first we access 01:37:01.739 --> 01:37:04.010 align:start position:0% so main takeaway first we access accounts<01:37:02.340> and<01:37:03.000> once<01:37:03.360> we<01:37:03.540> have<01:37:03.659> the<01:37:03.840> account 01:37:04.010 --> 01:37:04.020 align:start position:0% accounts and once we have the account 01:37:04.020 --> 01:37:06.470 align:start position:0% accounts and once we have the account storage<01:37:04.380> root<01:37:04.800> we<01:37:04.920> can<01:37:05.040> access<01:37:05.219> is<01:37:05.580> it's<01:37:06.060> it's 01:37:06.470 --> 01:37:06.480 align:start position:0% storage root we can access is it's it's 01:37:06.480 --> 01:37:07.729 align:start position:0% storage root we can access is it's it's the 01:37:07.729 --> 01:37:07.739 align:start position:0% the 01:37:07.739 --> 01:37:09.350 align:start position:0% the okay 01:37:09.350 --> 01:37:09.360 align:start position:0% okay 01:37:09.360 --> 01:37:10.189 align:start position:0% okay um 01:37:10.189 --> 01:37:10.199 align:start position:0% um 01:37:10.199 --> 01:37:13.610 align:start position:0% um cool<01:37:10.739> so<01:37:11.100> to<01:37:11.400> sum<01:37:11.520> it<01:37:11.699> up<01:37:12.080> like<01:37:13.080> the<01:37:13.320> background 01:37:13.610 --> 01:37:13.620 align:start position:0% cool so to sum it up like the background 01:37:13.620 --> 01:37:16.250 align:start position:0% cool so to sum it up like the background so<01:37:13.980> main<01:37:14.219> takeaways<01:37:14.760> given<01:37:15.540> the<01:37:15.840> block<01:37:15.960> stay 01:37:16.250 --> 01:37:16.260 align:start position:0% so main takeaways given the block stay 01:37:16.260 --> 01:37:19.490 align:start position:0% so main takeaways given the block stay true<01:37:16.440> to<01:37:16.739> you<01:37:16.860> can<01:37:16.980> recreate<01:37:17.760> any 01:37:19.490 --> 01:37:19.500 align:start position:0% true to you can recreate any 01:37:19.500 --> 01:37:22.790 align:start position:0% true to you can recreate any any<01:37:20.040> state<01:37:20.400> for<01:37:21.179> this<01:37:21.360> specific<01:37:21.659> block<01:37:21.960> on 01:37:22.790 --> 01:37:22.800 align:start position:0% any state for this specific block on 01:37:22.800 --> 01:37:23.810 align:start position:0% any state for this specific block on this<01:37:22.920> network 01:37:23.810 --> 01:37:23.820 align:start position:0% this network 01:37:23.820 --> 01:37:26.330 align:start position:0% this network and<01:37:24.540> given<01:37:24.900> an<01:37:25.020> initial<01:37:25.320> trusted<01:37:25.860> blockage 01:37:26.330 --> 01:37:26.340 align:start position:0% and given an initial trusted blockage 01:37:26.340 --> 01:37:28.790 align:start position:0% and given an initial trusted blockage you<01:37:27.000> can<01:37:27.179> essentially<01:37:27.540> recreate<01:37:28.260> all<01:37:28.560> the 01:37:28.790 --> 01:37:28.800 align:start position:0% you can essentially recreate all the 01:37:28.800 --> 01:37:31.310 align:start position:0% you can essentially recreate all the previous<01:37:29.100> headers<01:37:29.699> which<01:37:30.480> is<01:37:30.659> pretty<01:37:30.900> pretty 01:37:31.310 --> 01:37:31.320 align:start position:0% previous headers which is pretty pretty 01:37:31.320 --> 01:37:34.129 align:start position:0% previous headers which is pretty pretty cool<01:37:31.560> and<01:37:31.980> important<01:37:32.400> to<01:37:32.580> get<01:37:32.880> the<01:37:33.540> ideas<01:37:33.719> that 01:37:34.129 --> 01:37:34.139 align:start position:0% cool and important to get the ideas that 01:37:34.139 --> 01:37:35.930 align:start position:0% cool and important to get the ideas that I<01:37:34.260> will<01:37:34.380> explain<01:37:34.500> like<01:37:34.739> pretty<01:37:34.980> soon 01:37:35.930 --> 01:37:35.940 align:start position:0% I will explain like pretty soon 01:37:35.940 --> 01:37:38.689 align:start position:0% I will explain like pretty soon okay<01:37:36.420> so<01:37:37.260> as<01:37:37.560> it's<01:37:37.739> gonna<01:37:37.920> be<01:37:38.040> a<01:37:38.159> workshop<01:37:38.460> it's 01:37:38.689 --> 01:37:38.699 align:start position:0% okay so as it's gonna be a workshop it's 01:37:38.699 --> 01:37:41.870 align:start position:0% okay so as it's gonna be a workshop it's a<01:37:38.880> short<01:37:39.060> one<01:37:39.300> so<01:37:39.840> I<01:37:40.199> won't<01:37:40.440> let<01:37:41.040> you<01:37:41.219> code<01:37:41.460> but 01:37:41.870 --> 01:37:41.880 align:start position:0% a short one so I won't let you code but 01:37:41.880 --> 01:37:43.610 align:start position:0% a short one so I won't let you code but I<01:37:42.060> will<01:37:42.239> show<01:37:42.480> you<01:37:42.600> some<01:37:42.840> concrete<01:37:43.199> examples 01:37:43.610 --> 01:37:43.620 align:start position:0% I will show you some concrete examples 01:37:43.620 --> 01:37:46.370 align:start position:0% I will show you some concrete examples so<01:37:44.460> what<01:37:44.760> I<01:37:44.940> want<01:37:45.179> you<01:37:45.300> to<01:37:45.480> like<01:37:45.840> go<01:37:46.199> through 01:37:46.370 --> 01:37:46.380 align:start position:0% so what I want you to like go through 01:37:46.380 --> 01:37:49.790 align:start position:0% so what I want you to like go through with<01:37:46.800> me<01:37:46.980> today<01:37:47.159> is<01:37:47.820> how<01:37:48.179> we<01:37:48.360> can<01:37:48.659> prove<01:37:49.560> the 01:37:49.790 --> 01:37:49.800 align:start position:0% with me today is how we can prove the 01:37:49.800 --> 01:37:52.189 align:start position:0% with me today is how we can prove the ownership<01:37:50.159> of<01:37:50.520> Alliance<01:37:51.000> profile<01:37:51.360> on<01:37:51.840> another 01:37:52.189 --> 01:37:52.199 align:start position:0% ownership of Alliance profile on another 01:37:52.199 --> 01:37:53.209 align:start position:0% ownership of Alliance profile on another chain 01:37:53.209 --> 01:37:53.219 align:start position:0% chain 01:37:53.219 --> 01:37:54.970 align:start position:0% chain so 01:37:54.970 --> 01:37:54.980 align:start position:0% so 01:37:54.980 --> 01:37:57.590 align:start position:0% so a<01:37:55.980> bit<01:37:56.219> of<01:37:56.340> background<01:37:56.580> lens<01:37:56.940> profiles<01:37:57.540> are 01:37:57.590 --> 01:37:57.600 align:start position:0% a bit of background lens profiles are 01:37:57.600 --> 01:38:00.649 align:start position:0% a bit of background lens profiles are represented<01:37:58.080> as<01:37:58.199> nfts<01:37:58.800> and<01:37:59.639> lens<01:38:00.060> is<01:38:00.239> deployed 01:38:00.649 --> 01:38:00.659 align:start position:0% represented as nfts and lens is deployed 01:38:00.659 --> 01:38:05.229 align:start position:0% represented as nfts and lens is deployed on<01:38:00.840> polygon<01:38:01.500> I<01:38:02.219> think<01:38:02.360> that's<01:38:03.360> it<01:38:03.860> how<01:38:04.860> do<01:38:04.980> we 01:38:05.229 --> 01:38:05.239 align:start position:0% on polygon I think that's it how do we 01:38:05.239 --> 01:38:08.689 align:start position:0% on polygon I think that's it how do we get<01:38:06.239> to<01:38:06.420> this<01:38:06.600> so<01:38:07.320> first<01:38:07.679> of<01:38:07.800> all<01:38:07.920> the<01:38:08.520> question 01:38:08.689 --> 01:38:08.699 align:start position:0% get to this so first of all the question 01:38:08.699 --> 01:38:10.430 align:start position:0% get to this so first of all the question that<01:38:08.940> we<01:38:09.060> need<01:38:09.179> to<01:38:09.300> answer<01:38:09.480> to<01:38:09.719> ourselves<01:38:10.139> is 01:38:10.430 --> 01:38:10.440 align:start position:0% that we need to answer to ourselves is 01:38:10.440 --> 01:38:13.129 align:start position:0% that we need to answer to ourselves is how<01:38:11.219> does<01:38:11.400> Polygon<01:38:11.940> commit<01:38:12.239> to<01:38:12.420> ethereum<01:38:12.840> L1 01:38:13.129 --> 01:38:13.139 align:start position:0% how does Polygon commit to ethereum L1 01:38:13.139 --> 01:38:15.470 align:start position:0% how does Polygon commit to ethereum L1 because<01:38:13.860> if<01:38:14.159> we<01:38:14.280> want<01:38:14.460> to<01:38:14.580> like<01:38:15.000> let's<01:38:15.300> say 01:38:15.470 --> 01:38:15.480 align:start position:0% because if we want to like let's say 01:38:15.480 --> 01:38:17.750 align:start position:0% because if we want to like let's say prove<01:38:15.960> the<01:38:16.080> ownership<01:38:16.440> of<01:38:16.800> a<01:38:16.920> lens<01:38:17.100> profile<01:38:17.460> on 01:38:17.750 --> 01:38:17.760 align:start position:0% prove the ownership of a lens profile on 01:38:17.760 --> 01:38:19.970 align:start position:0% prove the ownership of a lens profile on optimism<01:38:18.659> we<01:38:18.900> need<01:38:19.020> to<01:38:19.080> know<01:38:19.260> the<01:38:19.500> state<01:38:19.739> route 01:38:19.970 --> 01:38:19.980 align:start position:0% optimism we need to know the state route 01:38:19.980 --> 01:38:24.229 align:start position:0% optimism we need to know the state route of<01:38:20.600> polygon<01:38:21.600> but<01:38:22.560> there<01:38:23.040> is<01:38:23.219> material<01:38:23.639> one<01:38:24.060> in 01:38:24.229 --> 01:38:24.239 align:start position:0% of polygon but there is material one in 01:38:24.239 --> 01:38:26.390 align:start position:0% of polygon but there is material one in the<01:38:24.360> middle<01:38:24.480> so<01:38:24.840> how<01:38:25.739> do<01:38:25.860> we<01:38:25.980> actually<01:38:26.100> access 01:38:26.390 --> 01:38:26.400 align:start position:0% the middle so how do we actually access 01:38:26.400 --> 01:38:29.629 align:start position:0% the middle so how do we actually access this<01:38:26.699> on<01:38:26.820> each<01:38:27.000> terminal<01:38:27.300> one<01:38:27.600> primarily<01:38:28.639> so 01:38:29.629 --> 01:38:29.639 align:start position:0% this on each terminal one primarily so 01:38:29.639 --> 01:38:32.390 align:start position:0% this on each terminal one primarily so uh<01:38:30.239> polygon<01:38:30.900> is<01:38:31.020> a<01:38:31.139> commitment<01:38:31.440> commit<01:38:32.040> commit 01:38:32.390 --> 01:38:32.400 align:start position:0% uh polygon is a commitment commit commit 01:38:32.400 --> 01:38:33.350 align:start position:0% uh polygon is a commitment commit commit chain 01:38:33.350 --> 01:38:33.360 align:start position:0% chain 01:38:33.360 --> 01:38:36.590 align:start position:0% chain and<01:38:34.020> it<01:38:34.199> commits<01:38:34.620> to<01:38:34.800> to<01:38:35.040> ethereum<01:38:35.460> a<01:38:36.239> bunch<01:38:36.480> of 01:38:36.590 --> 01:38:36.600 align:start position:0% and it commits to to ethereum a bunch of 01:38:36.600 --> 01:38:38.270 align:start position:0% and it commits to to ethereum a bunch of things<01:38:36.840> every 01:38:38.270 --> 01:38:38.280 align:start position:0% things every 01:38:38.280 --> 01:38:40.910 align:start position:0% things every some<01:38:38.760> amount<01:38:39.000> of<01:38:39.179> time<01:38:39.360> and<01:38:40.139> essentially<01:38:40.500> on 01:38:40.910 --> 01:38:40.920 align:start position:0% some amount of time and essentially on 01:38:40.920 --> 01:38:43.370 align:start position:0% some amount of time and essentially on L1<01:38:41.280> we<01:38:41.580> do<01:38:41.760> not<01:38:41.880> validate<01:38:42.420> the<01:38:42.900> entire<01:38:43.080> State 01:38:43.370 --> 01:38:43.380 align:start position:0% L1 we do not validate the entire State 01:38:43.380 --> 01:38:44.990 align:start position:0% L1 we do not validate the entire State transition<01:38:43.739> but<01:38:44.100> we<01:38:44.219> just<01:38:44.400> verify<01:38:44.820> the 01:38:44.990 --> 01:38:45.000 align:start position:0% transition but we just verify the 01:38:45.000 --> 01:38:47.830 align:start position:0% transition but we just verify the consensus<01:38:45.900> of<01:38:46.380> polygon<01:38:47.040> and<01:38:47.580> this 01:38:47.830 --> 01:38:47.840 align:start position:0% consensus of polygon and this 01:38:47.840 --> 01:38:50.870 align:start position:0% consensus of polygon and this checkpoints<01:38:48.840> how<01:38:49.080> they<01:38:49.380> call<01:38:49.560> it<01:38:49.880> essentially 01:38:50.870 --> 01:38:50.880 align:start position:0% checkpoints how they call it essentially 01:38:50.880 --> 01:38:54.470 align:start position:0% checkpoints how they call it essentially contain<01:38:51.540> uh<01:38:52.320> State<01:38:53.100> routes<01:38:53.580> and<01:38:54.060> so<01:38:54.179> I<01:38:54.360> mean 01:38:54.470 --> 01:38:54.480 align:start position:0% contain uh State routes and so I mean 01:38:54.480 --> 01:38:57.649 align:start position:0% contain uh State routes and so I mean not<01:38:54.840> directly<01:38:55.260> but<01:38:55.500> we<01:38:55.739> can<01:38:55.980> access<01:38:56.760> them<01:38:57.179> and 01:38:57.649 --> 01:38:57.659 align:start position:0% not directly but we can access them and 01:38:57.659 --> 01:39:01.129 align:start position:0% not directly but we can access them and let's<01:38:58.080> get<01:38:58.440> to<01:38:58.620> this<01:38:58.920> to<01:38:59.639> this<01:38:59.940> part 01:39:01.129 --> 01:39:01.139 align:start position:0% let's get to this to this part 01:39:01.139 --> 01:39:04.450 align:start position:0% let's get to this to this part so<01:39:01.800> this<01:39:02.100> is<01:39:02.219> taken<01:39:02.699> from<01:39:03.420> polygons 01:39:04.450 --> 01:39:04.460 align:start position:0% so this is taken from polygons 01:39:04.460 --> 01:39:07.310 align:start position:0% so this is taken from polygons documentation<01:39:05.480> and<01:39:06.480> this<01:39:06.719> is<01:39:06.840> how<01:39:07.139> a 01:39:07.310 --> 01:39:07.320 align:start position:0% documentation and this is how a 01:39:07.320 --> 01:39:09.709 align:start position:0% documentation and this is how a checkpoint<01:39:07.739> looks<01:39:08.159> like<01:39:08.280> so<01:39:09.120> as<01:39:09.300> you<01:39:09.480> can<01:39:09.600> see 01:39:09.709 --> 01:39:09.719 align:start position:0% checkpoint looks like so as you can see 01:39:09.719 --> 01:39:11.930 align:start position:0% checkpoint looks like so as you can see the<01:39:10.139> checkpoint<01:39:10.500> is<01:39:10.739> made<01:39:10.860> of<01:39:10.980> a<01:39:11.100> proposal<01:39:11.639> so 01:39:11.930 --> 01:39:11.940 align:start position:0% the checkpoint is made of a proposal so 01:39:11.940 --> 01:39:13.490 align:start position:0% the checkpoint is made of a proposal so who<01:39:12.179> proposed<01:39:12.659> The<01:39:12.719> Block 01:39:13.490 --> 01:39:13.500 align:start position:0% who proposed The Block 01:39:13.500 --> 01:39:16.250 align:start position:0% who proposed The Block start<01:39:14.100> lock<01:39:14.340> and<01:39:14.580> block<01:39:14.900> give<01:39:15.900> me<01:39:16.020> a<01:39:16.139> second 01:39:16.250 --> 01:39:16.260 align:start position:0% start lock and block give me a second 01:39:16.260 --> 01:39:18.410 align:start position:0% start lock and block give me a second I'll<01:39:16.500> get<01:39:16.679> to<01:39:16.800> this<01:39:16.980> and<01:39:17.639> most<01:39:17.880> importantly<01:39:18.239> we 01:39:18.410 --> 01:39:18.420 align:start position:0% I'll get to this and most importantly we 01:39:18.420 --> 01:39:20.450 align:start position:0% I'll get to this and most importantly we have<01:39:18.540> the<01:39:18.600> root<01:39:18.900> question<01:39:19.020> so<01:39:19.800> the<01:39:19.980> root<01:39:20.159> hush 01:39:20.450 --> 01:39:20.460 align:start position:0% have the root question so the root hush 01:39:20.460 --> 01:39:22.370 align:start position:0% have the root question so the root hush is<01:39:20.639> essentially<01:39:21.000> a<01:39:21.420> Merkle<01:39:21.900> tree<01:39:22.020> not<01:39:22.199> America 01:39:22.370 --> 01:39:22.380 align:start position:0% is essentially a Merkle tree not America 01:39:22.380 --> 01:39:25.370 align:start position:0% is essentially a Merkle tree not America Patricia<01:39:22.980> tree<01:39:23.159> that<01:39:23.880> contains<01:39:24.480> all<01:39:25.199> the 01:39:25.370 --> 01:39:25.380 align:start position:0% Patricia tree that contains all the 01:39:25.380 --> 01:39:27.950 align:start position:0% Patricia tree that contains all the headers<01:39:25.860> and<01:39:26.520> which<01:39:26.699> headers<01:39:27.179> the<01:39:27.420> headers<01:39:27.780> in 01:39:27.950 --> 01:39:27.960 align:start position:0% headers and which headers the headers in 01:39:27.960 --> 01:39:30.770 align:start position:0% headers and which headers the headers in the<01:39:28.080> range<01:39:28.320> of<01:39:28.500> start<01:39:28.739> block<01:39:29.040> and<01:39:29.520> end<01:39:29.760> block 01:39:30.770 --> 01:39:30.780 align:start position:0% the range of start block and end block 01:39:30.780 --> 01:39:32.030 align:start position:0% the range of start block and end block cool 01:39:32.030 --> 01:39:32.040 align:start position:0% cool 01:39:32.040 --> 01:39:34.250 align:start position:0% cool so<01:39:32.699> now 01:39:34.250 --> 01:39:34.260 align:start position:0% so now 01:39:34.260 --> 01:39:37.070 align:start position:0% so now if<01:39:34.800> we<01:39:34.920> get<01:39:35.159> back<01:39:35.280> to<01:39:35.520> the<01:39:35.639> previous<01:39:35.760> part<01:39:36.120> we 01:39:37.070 --> 01:39:37.080 align:start position:0% if we get back to the previous part we 01:39:37.080 --> 01:39:39.169 align:start position:0% if we get back to the previous part we can<01:39:37.260> essentially<01:39:37.620> prove<01:39:38.219> with<01:39:39.000> this 01:39:39.169 --> 01:39:39.179 align:start position:0% can essentially prove with this 01:39:39.179 --> 01:39:41.390 align:start position:0% can essentially prove with this commitment<01:39:39.600> that<01:39:39.900> we<01:39:40.080> know<01:39:40.260> the<01:39:40.500> valid<01:39:41.040> state 01:39:41.390 --> 01:39:41.400 align:start position:0% commitment that we know the valid state 01:39:41.400 --> 01:39:43.850 align:start position:0% commitment that we know the valid state route<01:39:41.639> of<01:39:42.000> polygon 01:39:43.850 --> 01:39:43.860 align:start position:0% route of polygon 01:39:43.860 --> 01:39:46.729 align:start position:0% route of polygon first<01:39:44.340> even<01:39:44.639> block 01:39:46.729 --> 01:39:46.739 align:start position:0% first even block 01:39:46.739 --> 01:39:49.129 align:start position:0% first even block okay<01:39:47.280> A<01:39:47.639> bit<01:39:47.820> of<01:39:47.940> Hands-On<01:39:48.360> so<01:39:48.659> we<01:39:48.900> want<01:39:49.020> to 01:39:49.129 --> 01:39:49.139 align:start position:0% okay A bit of Hands-On so we want to 01:39:49.139 --> 01:39:51.890 align:start position:0% okay A bit of Hands-On so we want to prove<01:39:49.560> that<01:39:50.219> I<01:39:50.460> own<01:39:50.639> a<01:39:50.880> lens<01:39:51.179> profile<01:39:51.600> on 01:39:51.890 --> 01:39:51.900 align:start position:0% prove that I own a lens profile on 01:39:51.900 --> 01:39:53.930 align:start position:0% prove that I own a lens profile on polygon<01:39:52.440> forever 01:39:53.930 --> 01:39:53.940 align:start position:0% polygon forever 01:39:53.940 --> 01:39:54.950 align:start position:0% polygon forever so 01:39:54.950 --> 01:39:54.960 align:start position:0% so 01:39:54.960 --> 01:39:58.250 align:start position:0% so number<01:39:55.320> one<01:39:55.620> we<01:39:56.340> go<01:39:56.580> to<01:39:56.699> the<01:39:56.880> contracts<01:39:57.360> we<01:39:58.020> see 01:39:58.250 --> 01:39:58.260 align:start position:0% number one we go to the contracts we see 01:39:58.260 --> 01:39:59.270 align:start position:0% number one we go to the contracts we see a<01:39:58.380> contract 01:39:59.270 --> 01:39:59.280 align:start position:0% a contract 01:39:59.280 --> 01:40:02.090 align:start position:0% a contract we<01:39:59.699> go<01:39:59.880> for<01:40:00.060> it<01:40:00.179> and<01:40:00.480> we<01:40:00.659> see<01:40:00.840> that<01:40:01.139> essentially 01:40:02.090 --> 01:40:02.100 align:start position:0% we go for it and we see that essentially 01:40:02.100 --> 01:40:04.010 align:start position:0% we go for it and we see that essentially there<01:40:02.460> is<01:40:02.580> a<01:40:02.639> bunch<01:40:02.760> of<01:40:03.000> logic<01:40:03.300> on<01:40:03.480> top<01:40:03.600> of<01:40:03.840> this 01:40:04.010 --> 01:40:04.020 align:start position:0% there is a bunch of logic on top of this 01:40:04.020 --> 01:40:05.930 align:start position:0% there is a bunch of logic on top of this erc721 01:40:05.930 --> 01:40:05.940 align:start position:0% erc721 01:40:05.940 --> 01:40:08.570 align:start position:0% erc721 this<01:40:06.480> is<01:40:06.600> like<01:40:06.780> the<01:40:07.139> basic<01:40:07.500> erc71<01:40:08.219> as<01:40:08.400> you<01:40:08.460> can 01:40:08.570 --> 01:40:08.580 align:start position:0% this is like the basic erc71 as you can 01:40:08.580 --> 01:40:10.669 align:start position:0% this is like the basic erc71 as you can see<01:40:08.639> it's<01:40:08.699> an<01:40:08.820> abstract<01:40:09.179> contract<01:40:09.540> and<01:40:10.440> it's 01:40:10.669 --> 01:40:10.679 align:start position:0% see it's an abstract contract and it's 01:40:10.679 --> 01:40:12.290 align:start position:0% see it's an abstract contract and it's slightly<01:40:11.040> modified 01:40:12.290 --> 01:40:12.300 align:start position:0% slightly modified 01:40:12.300 --> 01:40:13.850 align:start position:0% slightly modified instead<01:40:12.900> of<01:40:13.020> having<01:40:13.199> like<01:40:13.380> a<01:40:13.560> standard 01:40:13.850 --> 01:40:13.860 align:start position:0% instead of having like a standard 01:40:13.860 --> 01:40:16.490 align:start position:0% instead of having like a standard mapping<01:40:14.219> from<01:40:14.400> like<01:40:14.699> token<01:40:15.360> ID<01:40:15.480> to<01:40:15.840> its<01:40:16.199> owner 01:40:16.490 --> 01:40:16.500 align:start position:0% mapping from like token ID to its owner 01:40:16.500 --> 01:40:18.950 align:start position:0% mapping from like token ID to its owner we<01:40:16.980> have<01:40:17.100> like<01:40:17.280> token<01:40:17.699> ID<01:40:17.820> to<01:40:18.120> token<01:40:18.540> data 01:40:18.950 --> 01:40:18.960 align:start position:0% we have like token ID to token data 01:40:18.960 --> 01:40:22.550 align:start position:0% we have like token ID to token data token<01:40:19.620> data<01:40:19.920> is<01:40:19.980> a<01:40:20.219> struct<01:40:20.659> distract<01:40:21.659> is<01:40:22.080> 32 01:40:22.550 --> 01:40:22.560 align:start position:0% token data is a struct distract is 32 01:40:22.560 --> 01:40:24.709 align:start position:0% token data is a struct distract is 32 bytes<01:40:22.920> in<01:40:23.040> total<01:40:23.280> 20<01:40:23.639> bytes<01:40:24.179> is<01:40:24.300> the<01:40:24.420> actual 01:40:24.709 --> 01:40:24.719 align:start position:0% bytes in total 20 bytes is the actual 01:40:24.719 --> 01:40:26.629 align:start position:0% bytes in total 20 bytes is the actual owner<01:40:25.139> and<01:40:25.620> the<01:40:25.739> remaining<01:40:26.100> 12<01:40:26.219> bytes 01:40:26.629 --> 01:40:26.639 align:start position:0% owner and the remaining 12 bytes 01:40:26.639 --> 01:40:29.209 align:start position:0% owner and the remaining 12 bytes represent<01:40:26.940> one<01:40:27.300> the<01:40:27.600> token<01:40:27.900> was<01:40:28.020> minted 01:40:29.209 --> 01:40:29.219 align:start position:0% represent one the token was minted 01:40:29.219 --> 01:40:33.169 align:start position:0% represent one the token was minted okay<01:40:29.820> but<01:40:30.600> how<01:40:31.080> do<01:40:31.260> I<01:40:31.440> actually<01:40:31.760> prove<01:40:32.760> it<01:40:32.880> oh 01:40:33.169 --> 01:40:33.179 align:start position:0% okay but how do I actually prove it oh 01:40:33.179 --> 01:40:35.209 align:start position:0% okay but how do I actually prove it oh and<01:40:33.420> also<01:40:33.780> very<01:40:34.380> important<01:40:34.739> thing<01:40:34.980> when 01:40:35.209 --> 01:40:35.219 align:start position:0% and also very important thing when 01:40:35.219 --> 01:40:36.950 align:start position:0% and also very important thing when dealing<01:40:35.520> with<01:40:35.639> storage<01:40:35.880> layout<01:40:36.360> we<01:40:36.840> have 01:40:36.950 --> 01:40:36.960 align:start position:0% dealing with storage layout we have 01:40:36.960 --> 01:40:38.270 align:start position:0% dealing with storage layout we have something<01:40:37.199> that<01:40:37.500> is<01:40:37.560> called<01:40:37.739> like<01:40:37.920> slot 01:40:38.270 --> 01:40:38.280 align:start position:0% something that is called like slot 01:40:38.280 --> 01:40:41.990 align:start position:0% something that is called like slot indices<01:40:38.639> so<01:40:39.360> each<01:40:39.659> variable<01:40:40.139> has<01:40:40.980> a<01:40:41.280> given 01:40:41.990 --> 01:40:42.000 align:start position:0% indices so each variable has a given 01:40:42.000 --> 01:40:45.410 align:start position:0% indices so each variable has a given slot<01:40:42.420> like<01:40:42.659> in<01:40:42.840> the<01:40:43.080> some<01:40:43.980> sort<01:40:44.219> of<01:40:44.420> meta 01:40:45.410 --> 01:40:45.420 align:start position:0% slot like in the some sort of meta 01:40:45.420 --> 01:40:47.990 align:start position:0% slot like in the some sort of meta layout<01:40:45.719> I<01:40:46.020> call<01:40:46.139> it<01:40:46.260> like<01:40:46.440> that<01:40:46.620> it's<01:40:46.980> from<01:40:47.280> the 01:40:47.990 --> 01:40:48.000 align:start position:0% layout I call it like that it's from the 01:40:48.000 --> 01:40:50.090 align:start position:0% layout I call it like that it's from the right<01:40:48.120> way<01:40:48.300> anyways 01:40:50.090 --> 01:40:50.100 align:start position:0% right way anyways 01:40:50.100 --> 01:40:53.270 align:start position:0% right way anyways this<01:40:50.580> mapping<01:40:51.060> it<01:40:51.960> has<01:40:52.260> like<01:40:52.440> the<01:40:52.620> slot<01:40:52.920> index 01:40:53.270 --> 01:40:53.280 align:start position:0% this mapping it has like the slot index 01:40:53.280 --> 01:40:56.270 align:start position:0% this mapping it has like the slot index too<01:40:53.580> I<01:40:54.420> will<01:40:54.600> get<01:40:54.780> to<01:40:55.080> this<01:40:55.380> part<01:40:55.620> in<01:40:56.100> a<01:40:56.219> second 01:40:56.270 --> 01:40:56.280 align:start position:0% too I will get to this part in a second 01:40:56.280 --> 01:40:58.970 align:start position:0% too I will get to this part in a second why<01:40:56.639> it's<01:40:56.820> two<01:40:57.080> and<01:40:58.080> we<01:40:58.320> have<01:40:58.440> a<01:40:58.560> mapping<01:40:58.800> from 01:40:58.970 --> 01:40:58.980 align:start position:0% why it's two and we have a mapping from 01:40:58.980 --> 01:41:02.390 align:start position:0% why it's two and we have a mapping from token<01:40:59.400> ID<01:40:59.520> so<01:41:00.360> you<01:41:00.719> win<01:41:00.960> to<01:41:01.380> 32<01:41:01.800> bytes<01:41:02.040> of<01:41:02.159> data 01:41:02.390 --> 01:41:02.400 align:start position:0% token ID so you win to 32 bytes of data 01:41:02.400 --> 01:41:04.610 align:start position:0% token ID so you win to 32 bytes of data represented<01:41:03.360> as<01:41:03.480> a<01:41:03.600> structure<01:41:04.020> just<01:41:04.320> think<01:41:04.440> of 01:41:04.610 --> 01:41:04.620 align:start position:0% represented as a structure just think of 01:41:04.620 --> 01:41:06.709 align:start position:0% represented as a structure just think of it<01:41:04.739> as<01:41:04.920> some<01:41:05.159> bytes 01:41:06.709 --> 01:41:06.719 align:start position:0% it as some bytes 01:41:06.719 --> 01:41:07.930 align:start position:0% it as some bytes okay 01:41:07.930 --> 01:41:07.940 align:start position:0% okay 01:41:07.940 --> 01:41:11.810 align:start position:0% okay so<01:41:08.940> uh<01:41:09.540> I<01:41:09.780> guess<01:41:09.900> most<01:41:10.199> of<01:41:10.320> you<01:41:10.440> use<01:41:10.620> heart<01:41:10.800> hot 01:41:11.810 --> 01:41:11.820 align:start position:0% so uh I guess most of you use heart hot 01:41:11.820 --> 01:41:13.970 align:start position:0% so uh I guess most of you use heart hot so<01:41:12.300> I'm<01:41:12.540> gonna<01:41:12.659> present<01:41:13.080> on<01:41:13.320> on<01:41:13.560> hard<01:41:13.739> Hut 01:41:13.970 --> 01:41:13.980 align:start position:0% so I'm gonna present on on hard Hut 01:41:13.980 --> 01:41:16.310 align:start position:0% so I'm gonna present on on hard Hut there<01:41:14.280> is<01:41:14.400> a<01:41:14.639> very<01:41:14.760> very<01:41:14.940> cool<01:41:15.239> tool<01:41:15.659> to<01:41:16.199> deal 01:41:16.310 --> 01:41:16.320 align:start position:0% there is a very very cool tool to deal 01:41:16.320 --> 01:41:17.570 align:start position:0% there is a very very cool tool to deal with<01:41:16.560> storage<01:41:16.800> layouts<01:41:17.280> it's<01:41:17.400> called 01:41:17.570 --> 01:41:17.580 align:start position:0% with storage layouts it's called 01:41:17.580 --> 01:41:19.970 align:start position:0% with storage layouts it's called obviously<01:41:18.000> hard<01:41:18.179> hot<01:41:18.420> storage<01:41:18.719> layout<01:41:19.260> this 01:41:19.970 --> 01:41:19.980 align:start position:0% obviously hard hot storage layout this 01:41:19.980 --> 01:41:21.709 align:start position:0% obviously hard hot storage layout this is<01:41:20.040> how<01:41:20.280> you<01:41:20.460> install<01:41:21.000> it<01:41:21.239> it's<01:41:21.360> literally 01:41:21.709 --> 01:41:21.719 align:start position:0% is how you install it it's literally 01:41:21.719 --> 01:41:24.530 align:start position:0% is how you install it it's literally yarn<01:41:22.380> install<01:41:22.800> hardcode<01:41:23.520> storage<01:41:23.760> layout<01:41:24.179> you 01:41:24.530 --> 01:41:24.540 align:start position:0% yarn install hardcode storage layout you 01:41:24.540 --> 01:41:27.530 align:start position:0% yarn install hardcode storage layout you add<01:41:24.840> one<01:41:25.020> comment<01:41:25.380> to<01:41:25.620> your<01:41:25.800> heart<01:41:25.980> config<01:41:26.639> you 01:41:27.530 --> 01:41:27.540 align:start position:0% add one comment to your heart config you 01:41:27.540 --> 01:41:29.270 align:start position:0% add one comment to your heart config you write<01:41:27.840> a<01:41:28.020> new<01:41:28.139> script<01:41:28.380> that<01:41:28.920> contains 01:41:29.270 --> 01:41:29.280 align:start position:0% write a new script that contains 01:41:29.280 --> 01:41:31.550 align:start position:0% write a new script that contains literally<01:41:29.699> eight<01:41:30.060> lines<01:41:30.300> of<01:41:30.480> code<01:41:30.600> you<01:41:31.320> run 01:41:31.550 --> 01:41:31.560 align:start position:0% literally eight lines of code you run 01:41:31.560 --> 01:41:34.189 align:start position:0% literally eight lines of code you run the<01:41:31.739> script<01:41:31.980> and<01:41:32.340> you<01:41:32.460> get<01:41:32.580> this<01:41:32.760> weird<01:41:32.940> table 01:41:34.189 --> 01:41:34.199 align:start position:0% the script and you get this weird table 01:41:34.199 --> 01:41:35.810 align:start position:0% the script and you get this weird table and<01:41:34.679> what<01:41:34.920> does<01:41:35.100> it<01:41:35.219> what<01:41:35.460> does<01:41:35.580> it<01:41:35.699> really 01:41:35.810 --> 01:41:35.820 align:start position:0% and what does it what does it really 01:41:35.820 --> 01:41:37.910 align:start position:0% and what does it what does it really tell<01:41:36.119> you<01:41:36.239> and<01:41:36.659> oh<01:41:36.900> and<01:41:37.080> by<01:41:37.199> the<01:41:37.320> way<01:41:37.380> why<01:41:37.679> this 01:41:37.910 --> 01:41:37.920 align:start position:0% tell you and oh and by the way why this 01:41:37.920 --> 01:41:39.950 align:start position:0% tell you and oh and by the way why this tool<01:41:38.219> is<01:41:38.280> pretty<01:41:38.400> useful<01:41:38.760> as<01:41:39.420> you<01:41:39.600> see<01:41:39.719> this 01:41:39.950 --> 01:41:39.960 align:start position:0% tool is pretty useful as you see this 01:41:39.960 --> 01:41:43.010 align:start position:0% tool is pretty useful as you see this contract<01:41:40.320> is<01:41:40.500> abstract<01:41:41.060> so<01:41:42.060> some<01:41:42.840> other 01:41:43.010 --> 01:41:43.020 align:start position:0% contract is abstract so some other 01:41:43.020 --> 01:41:44.270 align:start position:0% contract is abstract so some other contracts 01:41:44.270 --> 01:41:44.280 align:start position:0% contracts 01:41:44.280 --> 01:41:46.790 align:start position:0% contracts then<01:41:45.119> does<01:41:45.420> it<01:41:45.540> still 01:41:46.790 --> 01:41:46.800 align:start position:0% then does it still 01:41:46.800 --> 01:41:48.709 align:start position:0% then does it still yeah<01:41:47.280> some<01:41:47.460> countries<01:41:47.820> can<01:41:48.000> inherit<01:41:48.360> from<01:41:48.540> it 01:41:48.709 --> 01:41:48.719 align:start position:0% yeah some countries can inherit from it 01:41:48.719 --> 01:41:50.870 align:start position:0% yeah some countries can inherit from it and<01:41:49.320> obviously<01:41:49.679> why<01:41:49.920> we<01:41:50.100> inherit<01:41:50.460> the<01:41:50.699> storage 01:41:50.870 --> 01:41:50.880 align:start position:0% and obviously why we inherit the storage 01:41:50.880 --> 01:41:52.370 align:start position:0% and obviously why we inherit the storage layout<01:41:51.300> I<01:41:51.540> mean<01:41:51.659> this<01:41:51.780> does<01:41:52.020> this<01:41:52.260> in 01:41:52.370 --> 01:41:52.380 align:start position:0% layout I mean this does this in 01:41:52.380 --> 01:41:54.950 align:start position:0% layout I mean this does this in synthesis<01:41:52.860> can<01:41:53.159> can<01:41:53.639> get<01:41:53.880> more<01:41:54.119> trickier 01:41:54.950 --> 01:41:54.960 align:start position:0% synthesis can can get more trickier 01:41:54.960 --> 01:41:57.470 align:start position:0% synthesis can can get more trickier because<01:41:55.500> it<01:41:55.800> also 01:41:57.470 --> 01:41:57.480 align:start position:0% because it also 01:41:57.480 --> 01:42:01.149 align:start position:0% because it also okay<01:41:58.139> so<01:41:58.980> that's 01:42:01.149 --> 01:42:01.159 align:start position:0% okay so that's 01:42:01.159 --> 01:42:03.890 align:start position:0% okay so that's it's<01:42:02.159> pretty<01:42:02.460> hard<01:42:02.699> to<01:42:02.880> coordinate<01:42:03.360> like<01:42:03.659> one 01:42:03.890 --> 01:42:03.900 align:start position:0% it's pretty hard to coordinate like one 01:42:03.900 --> 01:42:06.229 align:start position:0% it's pretty hard to coordinate like one hand<01:42:04.080> with<01:42:04.320> another<01:42:04.500> hand<01:42:04.920> even<01:42:05.880> though<01:42:06.060> I'm 01:42:06.229 --> 01:42:06.239 align:start position:0% hand with another hand even though I'm 01:42:06.239 --> 01:42:09.410 align:start position:0% hand with another hand even though I'm Italian<01:42:06.420> okay<01:42:06.840> anyways 01:42:09.410 --> 01:42:09.420 align:start position:0% Italian okay anyways 01:42:09.420 --> 01:42:12.830 align:start position:0% Italian okay anyways um<01:42:09.540> yeah<01:42:10.500> we<01:42:10.920> know<01:42:11.100> this<01:42:11.400> slot<01:42:11.820> in<01:42:12.300> the<01:42:12.420> in<01:42:12.659> the 01:42:12.830 --> 01:42:12.840 align:start position:0% um yeah we know this slot in the in the 01:42:12.840 --> 01:42:16.189 align:start position:0% um yeah we know this slot in the in the index<01:42:13.380> and<01:42:13.739> that's<01:42:13.860> how<01:42:14.340> we<01:42:14.460> get<01:42:14.820> it<01:42:15.000> we<01:42:15.900> have<01:42:16.020> a 01:42:16.189 --> 01:42:16.199 align:start position:0% index and that's how we get it we have a 01:42:16.199 --> 01:42:18.310 align:start position:0% index and that's how we get it we have a column<01:42:16.500> that<01:42:16.860> is<01:42:17.040> called 01:42:18.310 --> 01:42:18.320 align:start position:0% column that is called 01:42:18.320 --> 01:42:21.890 align:start position:0% column that is called storage<01:42:19.320> slot<01:42:20.040> and<01:42:20.699> as<01:42:20.820> you<01:42:21.000> see<01:42:21.119> underscore 01:42:21.890 --> 01:42:21.900 align:start position:0% storage slot and as you see underscore 01:42:21.900 --> 01:42:24.290 align:start position:0% storage slot and as you see underscore token<01:42:22.380> data<01:42:22.739> is<01:42:22.860> marked<01:42:23.219> as<01:42:23.340> two<01:42:23.580> and<01:42:24.179> that's 01:42:24.290 --> 01:42:24.300 align:start position:0% token data is marked as two and that's 01:42:24.300 --> 01:42:27.050 align:start position:0% token data is marked as two and that's it<01:42:24.480> okay<01:42:24.960> but<01:42:25.380> what<01:42:25.860> do<01:42:26.040> we<01:42:26.159> do<01:42:26.280> with<01:42:26.340> it<01:42:26.520> how<01:42:26.940> do 01:42:27.050 --> 01:42:27.060 align:start position:0% it okay but what do we do with it how do 01:42:27.060 --> 01:42:29.990 align:start position:0% it okay but what do we do with it how do we<01:42:27.179> get<01:42:27.300> this<01:42:27.719> storage<01:42:28.260> key 01:42:29.990 --> 01:42:30.000 align:start position:0% we get this storage key 01:42:30.000 --> 01:42:32.209 align:start position:0% we get this storage key and<01:42:30.659> yeah<01:42:30.960> that's<01:42:31.320> that's<01:42:31.619> it<01:42:31.800> let<01:42:31.980> me<01:42:32.100> check 01:42:32.209 --> 01:42:32.219 align:start position:0% and yeah that's that's it let me check 01:42:32.219 --> 01:42:34.669 align:start position:0% and yeah that's that's it let me check the<01:42:32.460> time<01:42:32.639> okay 01:42:34.669 --> 01:42:34.679 align:start position:0% the time okay 01:42:34.679 --> 01:42:35.930 align:start position:0% the time okay um<01:42:34.739> so 01:42:35.930 --> 01:42:35.940 align:start position:0% um so 01:42:35.940 --> 01:42:37.790 align:start position:0% um so a<01:42:36.420> bit<01:42:36.540> of<01:42:36.659> Hands-On<01:42:37.080> how<01:42:37.380> do<01:42:37.440> we<01:42:37.560> get<01:42:37.619> the 01:42:37.790 --> 01:42:37.800 align:start position:0% a bit of Hands-On how do we get the 01:42:37.800 --> 01:42:41.270 align:start position:0% a bit of Hands-On how do we get the actual<01:42:38.100> searches<01:42:38.520> it<01:42:39.119> sounds<01:42:39.360> scary<01:42:40.020> and<01:42:40.800> it's 01:42:41.270 --> 01:42:41.280 align:start position:0% actual searches it sounds scary and it's 01:42:41.280 --> 01:42:43.129 align:start position:0% actual searches it sounds scary and it's meant<01:42:41.580> to<01:42:41.699> be<01:42:41.760> scary<01:42:42.000> so 01:42:43.129 --> 01:42:43.139 align:start position:0% meant to be scary so 01:42:43.139 --> 01:42:45.229 align:start position:0% meant to be scary so we<01:42:43.500> know<01:42:43.619> the<01:42:43.739> slot<01:42:43.920> index<01:42:44.280> the<01:42:44.639> storage<01:42:44.820> index 01:42:45.229 --> 01:42:45.239 align:start position:0% we know the slot index the storage index 01:42:45.239 --> 01:42:49.870 align:start position:0% we know the slot index the storage index I<01:42:45.900> want<01:42:46.139> to<01:42:46.260> prove<01:42:46.679> that<01:42:47.100> it's<01:42:47.699> like<01:42:48.320> 0x35 01:42:49.870 --> 01:42:49.880 align:start position:0% I want to prove that it's like 0x35 01:42:49.880 --> 01:42:54.709 align:start position:0% I want to prove that it's like 0x35 owns<01:42:50.960> with<01:42:51.960> ID<01:42:52.320> 3594 01:42:54.709 --> 01:42:54.719 align:start position:0% owns with ID 3594 01:42:54.719 --> 01:42:57.709 align:start position:0% owns with ID 3594 how<01:42:55.199> do<01:42:55.380> we<01:42:55.500> get<01:42:55.619> the<01:42:55.800> storage<01:42:56.100> key 01:42:57.709 --> 01:42:57.719 align:start position:0% how do we get the storage key 01:42:57.719 --> 01:43:02.770 align:start position:0% how do we get the storage key we<01:42:58.139> essentially<01:42:58.500> do<01:42:58.739> this<01:42:58.920> operation<01:42:59.280> so<01:42:59.940> we 01:43:02.770 --> 01:43:02.780 align:start position:0% 01:43:02.780 --> 01:43:06.770 align:start position:0% concatenate<01:43:03.780> the<01:43:04.639> slot<01:43:05.639> I<01:43:06.179> mean<01:43:06.300> the<01:43:06.420> key<01:43:06.600> in 01:43:06.770 --> 01:43:06.780 align:start position:0% concatenate the slot I mean the key in 01:43:06.780 --> 01:43:09.350 align:start position:0% concatenate the slot I mean the key in the<01:43:06.900> mapping<01:43:07.199> which<01:43:07.860> is<01:43:07.980> 35.94<01:43:08.880> because<01:43:09.119> this 01:43:09.350 --> 01:43:09.360 align:start position:0% the mapping which is 35.94 because this 01:43:09.360 --> 01:43:11.390 align:start position:0% the mapping which is 35.94 because this is<01:43:09.480> the<01:43:09.600> token<01:43:09.960> ID<01:43:10.080> as<01:43:10.800> you<01:43:10.920> know<01:43:11.040> we<01:43:11.219> have<01:43:11.280> a 01:43:11.390 --> 01:43:11.400 align:start position:0% is the token ID as you know we have a 01:43:11.400 --> 01:43:13.070 align:start position:0% is the token ID as you know we have a mapping<01:43:11.699> from<01:43:11.820> token<01:43:12.119> ID<01:43:12.239> to<01:43:12.480> token<01:43:12.840> data 01:43:13.070 --> 01:43:13.080 align:start position:0% mapping from token ID to token data 01:43:13.080 --> 01:43:16.810 align:start position:0% mapping from token ID to token data token<01:43:13.560> data<01:43:13.860> contains<01:43:14.219> the<01:43:14.340> old<01:43:15.000> okay<01:43:15.480> so<01:43:15.900> we 01:43:16.810 --> 01:43:16.820 align:start position:0% token data contains the old okay so we 01:43:16.820 --> 01:43:20.629 align:start position:0% token data contains the old okay so we concatenate<01:43:17.820> this<01:43:18.000> with<01:43:18.360> the<01:43:18.600> storage<01:43:19.639> index 01:43:20.629 --> 01:43:20.639 align:start position:0% concatenate this with the storage index 01:43:20.639 --> 01:43:22.790 align:start position:0% concatenate this with the storage index we<01:43:21.300> hash<01:43:21.480> it<01:43:21.719> all<01:43:21.840> together<01:43:21.960> this<01:43:22.500> is<01:43:22.679> the 01:43:22.790 --> 01:43:22.800 align:start position:0% we hash it all together this is the 01:43:22.800 --> 01:43:25.430 align:start position:0% we hash it all together this is the storage<01:43:22.980> key<01:43:23.520> that<01:43:23.940> we<01:43:24.060> have<01:43:24.320> if<01:43:25.320> you're 01:43:25.430 --> 01:43:25.440 align:start position:0% storage key that we have if you're 01:43:25.440 --> 01:43:28.129 align:start position:0% storage key that we have if you're interested<01:43:25.860> how<01:43:26.280> to<01:43:26.460> deal<01:43:27.179> with<01:43:27.360> it<01:43:27.540> for<01:43:27.960> like 01:43:28.129 --> 01:43:28.139 align:start position:0% interested how to deal with it for like 01:43:28.139 --> 01:43:32.209 align:start position:0% interested how to deal with it for like more<01:43:28.320> complex<01:43:28.760> mappings<01:43:29.760> and<01:43:30.060> like 01:43:32.209 --> 01:43:32.219 align:start position:0% more complex mappings and like 01:43:32.219 --> 01:43:33.890 align:start position:0% more complex mappings and like layouts 01:43:33.890 --> 01:43:33.900 align:start position:0% layouts 01:43:33.900 --> 01:43:35.930 align:start position:0% layouts back<01:43:34.380> the<01:43:34.619> solidity<01:43:35.040> documentation<01:43:35.580> it's 01:43:35.930 --> 01:43:35.940 align:start position:0% back the solidity documentation it's 01:43:35.940 --> 01:43:38.270 align:start position:0% back the solidity documentation it's explained<01:43:36.480> pretty<01:43:36.659> well<01:43:36.900> so 01:43:38.270 --> 01:43:38.280 align:start position:0% explained pretty well so 01:43:38.280 --> 01:43:41.209 align:start position:0% explained pretty well so now<01:43:39.239> that's<01:43:39.719> to<01:43:40.080> make<01:43:40.199> sure<01:43:40.380> we<01:43:40.679> got<01:43:40.980> the 01:43:41.209 --> 01:43:41.219 align:start position:0% now that's to make sure we got the 01:43:41.219 --> 01:43:43.970 align:start position:0% now that's to make sure we got the proper<01:43:41.580> storage<01:43:42.540> key<01:43:42.900> let's<01:43:43.260> just<01:43:43.500> check<01:43:43.739> it 01:43:43.970 --> 01:43:43.980 align:start position:0% proper storage key let's just check it 01:43:43.980 --> 01:43:46.250 align:start position:0% proper storage key let's just check it how<01:43:44.159> we<01:43:44.280> can<01:43:44.400> check<01:43:44.520> it<01:43:44.760> super<01:43:45.420> easy<01:43:45.719> let's 01:43:46.250 --> 01:43:46.260 align:start position:0% how we can check it super easy let's 01:43:46.260 --> 01:43:48.550 align:start position:0% how we can check it super easy let's just<01:43:46.560> make<01:43:46.679> a<01:43:46.920> one<01:43:47.040> liter<01:43:47.340> PC<01:43:47.639> call 01:43:48.550 --> 01:43:48.560 align:start position:0% just make a one liter PC call 01:43:48.560 --> 01:43:51.530 align:start position:0% just make a one liter PC call to<01:43:49.560> get<01:43:49.679> this<01:43:49.980> storage<01:43:50.400> at<01:43:50.639> some<01:43:50.820> specific<01:43:51.119> key 01:43:51.530 --> 01:43:51.540 align:start position:0% to get this storage at some specific key 01:43:51.540 --> 01:43:52.810 align:start position:0% to get this storage at some specific key please 01:43:52.810 --> 01:43:52.820 align:start position:0% please 01:43:52.820 --> 01:43:57.050 align:start position:0% please if<01:43:53.820> get<01:43:54.119> storage<01:43:54.420> at<01:43:54.900> so<01:43:55.500> the<01:43:55.739> parameters<01:43:56.280> we 01:43:57.050 --> 01:43:57.060 align:start position:0% if get storage at so the parameters we 01:43:57.060 --> 01:43:58.790 align:start position:0% if get storage at so the parameters we want<01:43:57.179> to<01:43:57.300> access<01:43:57.480> the<01:43:57.780> storage<01:43:57.960> of<01:43:58.260> what<01:43:58.500> of 01:43:58.790 --> 01:43:58.800 align:start position:0% want to access the storage of what of 01:43:58.800 --> 01:44:02.510 align:start position:0% want to access the storage of what of the<01:43:59.159> lens<01:43:59.699> Hub<01:44:00.500> lens<01:44:01.500> cap<01:44:01.679> is<01:44:01.860> a<01:44:02.040> contract<01:44:02.280> that 01:44:02.510 --> 01:44:02.520 align:start position:0% the lens Hub lens cap is a contract that 01:44:02.520 --> 01:44:04.550 align:start position:0% the lens Hub lens cap is a contract that essentially<01:44:02.940> is<01:44:03.719> the<01:44:03.900> representation<01:44:04.380> of 01:44:04.550 --> 01:44:04.560 align:start position:0% essentially is the representation of 01:44:04.560 --> 01:44:08.390 align:start position:0% essentially is the representation of these<01:44:04.739> profiles<01:44:05.239> and<01:44:06.239> its<01:44:06.600> address<01:44:06.659> is<01:44:07.400> 0xdd4 01:44:08.390 --> 01:44:08.400 align:start position:0% these profiles and its address is 0xdd4 01:44:08.400 --> 01:44:13.149 align:start position:0% these profiles and its address is 0xdd4 and<01:44:09.000> so<01:44:09.119> on<01:44:09.360> and<01:44:10.320> this 01:44:13.149 --> 01:44:13.159 align:start position:0% 01:44:13.159 --> 01:44:17.510 align:start position:0% oh<01:44:14.159> is<01:44:15.060> it<01:44:15.179> better<01:44:15.360> oh<01:44:15.659> it's<01:44:15.960> much<01:44:16.080> better<01:44:16.520> and 01:44:17.510 --> 01:44:17.520 align:start position:0% oh is it better oh it's much better and 01:44:17.520 --> 01:44:22.790 align:start position:0% oh is it better oh it's much better and this<01:44:17.820> is<01:44:18.060> the<01:44:18.659> the<01:44:19.500> storage<01:44:19.920> key<01:44:20.639> is<01:44:21.500> 0x1<01:44:22.500> so 01:44:22.790 --> 01:44:22.800 align:start position:0% this is the the storage key is 0x1 so 01:44:22.800 --> 01:44:24.830 align:start position:0% this is the the storage key is 0x1 so essentially<01:44:23.219> that's<01:44:23.460> the<01:44:23.699> hash<01:44:23.820> the<01:44:24.119> 2E<01:44:24.659> got 01:44:24.830 --> 01:44:24.840 align:start position:0% essentially that's the hash the 2E got 01:44:24.840 --> 01:44:29.510 align:start position:0% essentially that's the hash the 2E got and<01:44:25.380> the<01:44:25.500> result<01:44:25.679> is<01:44:26.340> 0x000. 01:44:29.510 --> 01:44:29.520 align:start position:0% 01:44:29.520 --> 01:44:31.729 align:start position:0% and<01:44:30.000> we<01:44:30.239> know<01:44:30.360> that<01:44:30.480> it's<01:44:30.659> 32<01:44:31.020> bytes<01:44:31.320> of<01:44:31.440> data 01:44:31.729 --> 01:44:31.739 align:start position:0% and we know that it's 32 bytes of data 01:44:31.739 --> 01:44:34.669 align:start position:0% and we know that it's 32 bytes of data where<01:44:31.980> we<01:44:32.159> have<01:44:32.280> 20<01:44:32.639> and<01:44:33.000> 12.<01:44:33.540> so<01:44:33.780> let's<01:44:34.139> split 01:44:34.669 --> 01:44:34.679 align:start position:0% where we have 20 and 12. so let's split 01:44:34.679 --> 01:44:37.189 align:start position:0% where we have 20 and 12. so let's split it<01:44:34.800> into<01:44:34.980> 12<01:44:35.159> and<01:44:35.400> 20<01:44:35.580> bytes<01:44:36.060> and<01:44:36.600> what<01:44:36.780> we<01:44:37.020> have 01:44:37.189 --> 01:44:37.199 align:start position:0% it into 12 and 20 bytes and what we have 01:44:37.199 --> 01:44:39.590 align:start position:0% it into 12 and 20 bytes and what we have is 01:44:39.590 --> 01:44:39.600 align:start position:0% is 01:44:39.600 --> 01:44:42.590 align:start position:0% is some<01:44:40.260> number<01:44:40.500> like<01:44:40.860> you<01:44:41.040> can<01:44:41.340> see<01:44:41.460> Zero<01:44:42.000> x<01:44:42.239> a 01:44:42.590 --> 01:44:42.600 align:start position:0% some number like you can see Zero x a 01:44:42.600 --> 01:44:46.729 align:start position:0% some number like you can see Zero x a lot<01:44:42.719> of<01:44:42.900> zeros<01:44:43.320> then<01:44:43.679> 62<01:44:44.219> till<01:44:44.940> D<01:44:45.500> and<01:44:46.500> this 01:44:46.729 --> 01:44:46.739 align:start position:0% lot of zeros then 62 till D and this 01:44:46.739 --> 01:44:48.770 align:start position:0% lot of zeros then 62 till D and this looks<01:44:46.980> like<01:44:47.100> a<01:44:47.219> small<01:44:47.400> number<01:44:47.639> so<01:44:48.179> apparently 01:44:48.770 --> 01:44:48.780 align:start position:0% looks like a small number so apparently 01:44:48.780 --> 01:44:50.990 align:start position:0% looks like a small number so apparently it<01:44:48.960> is<01:44:49.139> a<01:44:49.320> timestamp<01:44:49.679> and<01:44:50.219> the<01:44:50.340> second<01:44:50.460> part<01:44:50.760> is 01:44:50.990 --> 01:44:51.000 align:start position:0% it is a timestamp and the second part is 01:44:51.000 --> 01:44:52.430 align:start position:0% it is a timestamp and the second part is like<01:44:51.179> 35 01:44:52.430 --> 01:44:52.440 align:start position:0% like 35 01:44:52.440 --> 01:44:55.850 align:start position:0% like 35 7<01:44:53.280> and<01:44:53.760> it's<01:44:53.940> literally<01:44:54.239> our<01:44:54.600> address<01:44:54.840> so<01:44:55.560> we 01:44:55.850 --> 01:44:55.860 align:start position:0% 7 and it's literally our address so we 01:44:55.860 --> 01:44:58.609 align:start position:0% 7 and it's literally our address so we got<01:44:55.980> it<01:44:56.159> correct<01:44:56.460> we<01:44:56.760> have<01:44:57.000> the<01:44:57.179> proper 01:44:58.609 --> 01:44:58.619 align:start position:0% got it correct we have the proper 01:44:58.619 --> 01:45:01.609 align:start position:0% got it correct we have the proper storage<01:44:59.280> key<01:44:59.639> cool 01:45:01.609 --> 01:45:01.619 align:start position:0% storage key cool 01:45:01.619 --> 01:45:03.189 align:start position:0% storage key cool foreign 01:45:03.189 --> 01:45:03.199 align:start position:0% foreign 01:45:03.199 --> 01:45:06.050 align:start position:0% foreign but<01:45:04.199> how<01:45:04.860> do<01:45:04.980> we<01:45:05.100> actually<01:45:05.280> get<01:45:05.639> to<01:45:05.820> storage 01:45:06.050 --> 01:45:06.060 align:start position:0% but how do we actually get to storage 01:45:06.060 --> 01:45:09.590 align:start position:0% but how do we actually get to storage proofs<01:45:06.600> so<01:45:07.400> blurb<01:45:08.400> standardized<01:45:09.000> method<01:45:09.239> in 01:45:09.590 --> 01:45:09.600 align:start position:0% proofs so blurb standardized method in 01:45:09.600 --> 01:45:11.570 align:start position:0% proofs so blurb standardized method in like<01:45:09.780> the<01:45:10.020> Json<01:45:10.380> or<01:45:10.560> PC<01:45:10.920> standard<01:45:11.340> for 01:45:11.570 --> 01:45:11.580 align:start position:0% like the Json or PC standard for 01:45:11.580 --> 01:45:14.090 align:start position:0% like the Json or PC standard for ethereum<01:45:12.060> clients<01:45:12.600> and<01:45:13.380> this<01:45:13.679> method<01:45:13.980> is 01:45:14.090 --> 01:45:14.100 align:start position:0% ethereum clients and this method is 01:45:14.100 --> 01:45:16.189 align:start position:0% ethereum clients and this method is called<01:45:14.280> eth<01:45:14.580> get<01:45:14.940> proof<01:45:15.239> which<01:45:15.719> essentially 01:45:16.189 --> 01:45:16.199 align:start position:0% called eth get proof which essentially 01:45:16.199 --> 01:45:20.390 align:start position:0% called eth get proof which essentially given<01:45:16.940> the<01:45:17.940> contract<01:45:18.420> address<01:45:18.659> so<01:45:19.080> I'm<01:45:20.040> better 01:45:20.390 --> 01:45:20.400 align:start position:0% given the contract address so I'm better 01:45:20.400 --> 01:45:22.310 align:start position:0% given the contract address so I'm better call<01:45:20.699> it<01:45:20.880> account<01:45:21.179> address<01:45:21.540> in<01:45:21.900> this<01:45:22.020> specific 01:45:22.310 --> 01:45:22.320 align:start position:0% call it account address in this specific 01:45:22.320 --> 01:45:24.649 align:start position:0% call it account address in this specific case<01:45:22.560> allows<01:45:23.340> us<01:45:23.460> to<01:45:23.639> generate<01:45:23.940> a<01:45:24.119> state<01:45:24.239> proof 01:45:24.649 --> 01:45:24.659 align:start position:0% case allows us to generate a state proof 01:45:24.659 --> 01:45:27.950 align:start position:0% case allows us to generate a state proof and<01:45:25.619> the<01:45:25.860> last<01:45:26.219> argument<01:45:26.639> I<01:45:27.000> mean<01:45:27.179> the<01:45:27.659> sorry 01:45:27.950 --> 01:45:27.960 align:start position:0% and the last argument I mean the sorry 01:45:27.960 --> 01:45:29.930 align:start position:0% and the last argument I mean the sorry the<01:45:28.199> second<01:45:28.380> argument<01:45:28.800> is<01:45:29.340> an<01:45:29.460> array<01:45:29.760> that 01:45:29.930 --> 01:45:29.940 align:start position:0% the second argument is an array that 01:45:29.940 --> 01:45:32.750 align:start position:0% the second argument is an array that contains<01:45:30.300> all<01:45:30.480> this<01:45:30.659> Storage<01:45:31.280> storage<01:45:32.280> keys 01:45:32.750 --> 01:45:32.760 align:start position:0% contains all this Storage storage keys 01:45:32.760 --> 01:45:35.570 align:start position:0% contains all this Storage storage keys that<01:45:33.119> we<01:45:33.300> want<01:45:33.420> to<01:45:33.540> prove<01:45:34.320> uh<01:45:35.219> there<01:45:35.460> is 01:45:35.570 --> 01:45:35.580 align:start position:0% that we want to prove uh there is 01:45:35.580 --> 01:45:37.149 align:start position:0% that we want to prove uh there is another<01:45:35.699> argument<01:45:36.179> which<01:45:36.420> is 01:45:37.149 --> 01:45:37.159 align:start position:0% another argument which is 01:45:37.159 --> 01:45:39.530 align:start position:0% another argument which is 0x1a<01:45:38.159> it's<01:45:38.580> essentially<01:45:38.940> the<01:45:39.119> block<01:45:39.239> number 01:45:39.530 --> 01:45:39.540 align:start position:0% 0x1a it's essentially the block number 01:45:39.540 --> 01:45:42.290 align:start position:0% 0x1a it's essentially the block number for<01:45:39.960> which<01:45:40.199> we<01:45:40.380> prove<01:45:40.619> the<01:45:40.800> state 01:45:42.290 --> 01:45:42.300 align:start position:0% for which we prove the state 01:45:42.300 --> 01:45:45.109 align:start position:0% for which we prove the state um<01:45:42.360> yeah<01:45:42.719> let's<01:45:43.139> call<01:45:43.440> this<01:45:43.679> method<01:45:44.040> oh<01:45:44.760> by<01:45:45.000> the 01:45:45.109 --> 01:45:45.119 align:start position:0% um yeah let's call this method oh by the 01:45:45.119 --> 01:45:46.850 align:start position:0% um yeah let's call this method oh by the way<01:45:45.239> uh<01:45:45.600> you<01:45:45.780> might<01:45:45.900> have<01:45:46.020> a<01:45:46.139> question<01:45:46.260> how<01:45:46.619> do 01:45:46.850 --> 01:45:46.860 align:start position:0% way uh you might have a question how do 01:45:46.860 --> 01:45:49.430 align:start position:0% way uh you might have a question how do we<01:45:46.980> deal<01:45:47.219> with<01:45:47.639> this<01:45:47.940> method<01:45:48.300> on<01:45:48.540> non-evm 01:45:49.430 --> 01:45:49.440 align:start position:0% we deal with this method on non-evm 01:45:49.440 --> 01:45:52.970 align:start position:0% we deal with this method on non-evm chains<01:45:50.060> because<01:45:51.060> for<01:45:51.420> example<01:45:51.800> on<01:45:52.800> some 01:45:52.970 --> 01:45:52.980 align:start position:0% chains because for example on some 01:45:52.980 --> 01:45:54.709 align:start position:0% chains because for example on some specific<01:45:53.340> Roll-Ups<01:45:54.000> this<01:45:54.179> method<01:45:54.420> is<01:45:54.540> like 01:45:54.709 --> 01:45:54.719 align:start position:0% specific Roll-Ups this method is like 01:45:54.719 --> 01:45:57.290 align:start position:0% specific Roll-Ups this method is like not<01:45:54.840> supported<01:45:55.320> actually<01:45:55.860> it's<01:45:56.100> not<01:45:56.400> a<01:45:56.880> big 01:45:57.290 --> 01:45:57.300 align:start position:0% not supported actually it's not a big 01:45:57.300 --> 01:45:59.030 align:start position:0% not supported actually it's not a big deal<01:45:57.480> because<01:45:57.900> if<01:45:58.199> you<01:45:58.320> think<01:45:58.440> of<01:45:58.560> it<01:45:58.679> we<01:45:58.920> just 01:45:59.030 --> 01:45:59.040 align:start position:0% deal because if you think of it we just 01:45:59.040 --> 01:46:01.250 align:start position:0% deal because if you think of it we just need<01:45:59.280> the<01:45:59.460> database<01:45:59.940> and<01:46:00.659> on<01:46:00.900> top<01:46:01.020> of<01:46:01.139> this 01:46:01.250 --> 01:46:01.260 align:start position:0% need the database and on top of this 01:46:01.260 --> 01:46:02.750 align:start position:0% need the database and on top of this database<01:46:01.679> we<01:46:01.920> can<01:46:02.040> literally<01:46:02.280> build<01:46:02.580> this 01:46:02.750 --> 01:46:02.760 align:start position:0% database we can literally build this 01:46:02.760 --> 01:46:05.270 align:start position:0% database we can literally build this method<01:46:03.360> we<01:46:03.900> just<01:46:04.260> need<01:46:04.440> to<01:46:04.500> know<01:46:04.679> how<01:46:04.980> the 01:46:05.270 --> 01:46:05.280 align:start position:0% method we just need to know how the 01:46:05.280 --> 01:46:08.050 align:start position:0% method we just need to know how the storage<01:46:06.179> is<01:46:06.480> constructed 01:46:08.050 --> 01:46:08.060 align:start position:0% storage is constructed 01:46:08.060 --> 01:46:12.050 align:start position:0% storage is constructed okay<01:46:09.060> this<01:46:09.659> is<01:46:09.719> the<01:46:09.900> proof<01:46:10.199> it<01:46:10.920> looks<01:46:11.219> scary<01:46:11.340> it 01:46:12.050 --> 01:46:12.060 align:start position:0% okay this is the proof it looks scary it 01:46:12.060 --> 01:46:14.390 align:start position:0% okay this is the proof it looks scary it is<01:46:12.179> scary<01:46:12.380> this<01:46:13.380> entire<01:46:13.679> object<01:46:14.040> is<01:46:14.219> four 01:46:14.390 --> 01:46:14.400 align:start position:0% is scary this entire object is four 01:46:14.400 --> 01:46:17.390 align:start position:0% is scary this entire object is four kilobytes<01:46:14.880> of<01:46:15.060> data<01:46:15.420> and<01:46:16.139> now<01:46:16.380> I<01:46:16.980> mentioned 01:46:17.390 --> 01:46:17.400 align:start position:0% kilobytes of data and now I mentioned 01:46:17.400 --> 01:46:20.270 align:start position:0% kilobytes of data and now I mentioned before<01:46:17.820> that<01:46:18.480> the<01:46:19.080> state<01:46:19.619> is<01:46:19.920> like<01:46:20.040> a<01:46:20.159> two 01:46:20.270 --> 01:46:20.280 align:start position:0% before that the state is like a two 01:46:20.280 --> 01:46:22.310 align:start position:0% before that the state is like a two level<01:46:20.460> structure<01:46:21.000> first<01:46:21.600> we<01:46:21.840> have<01:46:21.960> a<01:46:22.080> proof 01:46:22.310 --> 01:46:22.320 align:start position:0% level structure first we have a proof 01:46:22.320 --> 01:46:24.350 align:start position:0% level structure first we have a proof for<01:46:22.500> the<01:46:22.619> account<01:46:22.739> itself<01:46:23.280> and<01:46:24.000> then<01:46:24.119> we<01:46:24.239> have 01:46:24.350 --> 01:46:24.360 align:start position:0% for the account itself and then we have 01:46:24.360 --> 01:46:27.290 align:start position:0% for the account itself and then we have the<01:46:24.600> proof<01:46:25.020> for<01:46:25.920> the<01:46:26.280> storage<01:46:26.460> I<01:46:26.820> mean<01:46:26.940> for<01:46:27.119> the 01:46:27.290 --> 01:46:27.300 align:start position:0% the proof for the storage I mean for the 01:46:27.300 --> 01:46:30.410 align:start position:0% the proof for the storage I mean for the actual<01:46:27.540> storage<01:46:27.780> slot<01:46:28.400> it<01:46:29.400> is<01:46:29.580> scary<01:46:29.760> it's 01:46:30.410 --> 01:46:30.420 align:start position:0% actual storage slot it is scary it's 01:46:30.420 --> 01:46:33.410 align:start position:0% actual storage slot it is scary it's meant<01:46:30.719> to<01:46:30.840> be<01:46:30.960> scary<01:46:31.340> one<01:46:32.340> proof<01:46:32.760> is<01:46:32.940> like<01:46:33.179> more 01:46:33.410 --> 01:46:33.420 align:start position:0% meant to be scary one proof is like more 01:46:33.420 --> 01:46:37.310 align:start position:0% meant to be scary one proof is like more or<01:46:33.600> less<01:46:33.659> 600<01:46:34.440> bytes<01:46:35.600> 700<01:46:36.600> bytes<01:46:37.020> it<01:46:37.199> really 01:46:37.310 --> 01:46:37.320 align:start position:0% or less 600 bytes 700 bytes it really 01:46:37.320 --> 01:46:39.350 align:start position:0% or less 600 bytes 700 bytes it really depends<01:46:37.980> like<01:46:38.100> bigger<01:46:38.460> the<01:46:38.639> storage<01:46:38.820> is<01:46:39.119> than 01:46:39.350 --> 01:46:39.360 align:start position:0% depends like bigger the storage is than 01:46:39.360 --> 01:46:41.209 align:start position:0% depends like bigger the storage is than bigger<01:46:39.780> the<01:46:39.900> proof<01:46:40.199> is<01:46:40.320> and<01:46:40.860> also<01:46:41.040> more 01:46:41.209 --> 01:46:41.219 align:start position:0% bigger the proof is and also more 01:46:41.219 --> 01:46:43.129 align:start position:0% bigger the proof is and also more accounts<01:46:41.639> we<01:46:41.820> have<01:46:42.000> than<01:46:42.239> bigger<01:46:42.780> the<01:46:42.900> account 01:46:43.129 --> 01:46:43.139 align:start position:0% accounts we have than bigger the account 01:46:43.139 --> 01:46:44.450 align:start position:0% accounts we have than bigger the account proof<01:46:43.619> is 01:46:44.450 --> 01:46:44.460 align:start position:0% proof is 01:46:44.460 --> 01:46:47.930 align:start position:0% proof is so<01:46:45.119> that's<01:46:45.360> a<01:46:45.540> lot<01:46:45.659> of<01:46:45.780> cool<01:46:45.900> data<01:46:46.380> if<01:46:47.520> um<01:46:47.520> if 01:46:47.930 --> 01:46:47.940 align:start position:0% so that's a lot of cool data if um if 01:46:47.940 --> 01:46:51.229 align:start position:0% so that's a lot of cool data if um if you<01:46:48.060> can<01:46:48.179> imagine<01:46:48.360> you<01:46:49.139> can<01:46:49.320> imagine<01:46:49.820> uh<01:46:50.820> and 01:46:51.229 --> 01:46:51.239 align:start position:0% you can imagine you can imagine uh and 01:46:51.239 --> 01:46:52.970 align:start position:0% you can imagine you can imagine uh and yeah<01:46:51.420> that's<01:46:51.780> that's<01:46:52.020> pretty<01:46:52.320> bad<01:46:52.560> why 01:46:52.970 --> 01:46:52.980 align:start position:0% yeah that's that's pretty bad why 01:46:52.980 --> 01:46:54.830 align:start position:0% yeah that's that's pretty bad why because<01:46:53.219> we<01:46:53.460> need<01:46:53.639> to<01:46:53.760> pause<01:46:54.060> this<01:46:54.300> proof<01:46:54.659> on 01:46:54.830 --> 01:46:54.840 align:start position:0% because we need to pause this proof on 01:46:54.840 --> 01:46:57.350 align:start position:0% because we need to pause this proof on the<01:46:55.020> Chain<01:46:55.139> so<01:46:55.500> it's<01:46:55.679> a<01:46:55.860> lot<01:46:55.980> of<01:46:56.100> cool<01:46:56.280> data<01:46:56.760> but 01:46:57.350 --> 01:46:57.360 align:start position:0% the Chain so it's a lot of cool data but 01:46:57.360 --> 01:47:00.109 align:start position:0% the Chain so it's a lot of cool data but okay<01:46:57.540> let's<01:46:58.080> let's<01:46:58.380> try 01:47:00.109 --> 01:47:00.119 align:start position:0% okay let's let's try 01:47:00.119 --> 01:47:02.750 align:start position:0% okay let's let's try what's<01:47:00.600> going<01:47:00.840> to<01:47:00.960> be<01:47:01.020> the<01:47:01.199> cost<01:47:01.320> on<01:47:01.679> like<01:47:02.040> an 01:47:02.750 --> 01:47:02.760 align:start position:0% what's going to be the cost on like an 01:47:02.760 --> 01:47:05.870 align:start position:0% what's going to be the cost on like an evm<01:47:03.179> chain<01:47:03.420> that's<01:47:04.139> the<01:47:04.440> cost<01:47:04.560> it's<01:47:04.860> like<01:47:05.040> 600k 01:47:05.870 --> 01:47:05.880 align:start position:0% evm chain that's the cost it's like 600k 01:47:05.880 --> 01:47:09.890 align:start position:0% evm chain that's the cost it's like 600k of<01:47:06.179> gas<01:47:06.420> that's<01:47:07.260> a<01:47:07.440> lot<01:47:07.820> that<01:47:08.820> kills<01:47:09.540> almost 01:47:09.890 --> 01:47:09.900 align:start position:0% of gas that's a lot that kills almost 01:47:09.900 --> 01:47:12.290 align:start position:0% of gas that's a lot that kills almost every<01:47:10.440> single<01:47:10.860> application<01:47:11.699> that<01:47:12.119> you<01:47:12.179> want 01:47:12.290 --> 01:47:12.300 align:start position:0% every single application that you want 01:47:12.300 --> 01:47:14.510 align:start position:0% every single application that you want to<01:47:12.480> build<01:47:12.600> on<01:47:12.840> top<01:47:13.020> of<01:47:13.139> this<01:47:13.260> nice<01:47:13.440> primitive 01:47:14.510 --> 01:47:14.520 align:start position:0% to build on top of this nice primitive 01:47:14.520 --> 01:47:16.970 align:start position:0% to build on top of this nice primitive so<01:47:15.300> it's<01:47:15.719> pretty<01:47:15.900> bad<01:47:16.139> and<01:47:16.380> why<01:47:16.560> is<01:47:16.679> it<01:47:16.860> that 01:47:16.970 --> 01:47:16.980 align:start position:0% so it's pretty bad and why is it that 01:47:16.980 --> 01:47:19.970 align:start position:0% so it's pretty bad and why is it that bad<01:47:17.300> so<01:47:18.300> I<01:47:18.900> explained<01:47:19.320> on<01:47:19.619> the<01:47:19.739> high<01:47:19.800> level 01:47:19.970 --> 01:47:19.980 align:start position:0% bad so I explained on the high level 01:47:19.980 --> 01:47:21.770 align:start position:0% bad so I explained on the high level what<01:47:20.280> Merkel<01:47:20.639> trees<01:47:20.880> are<01:47:20.940> America<01:47:21.179> Patricia 01:47:21.770 --> 01:47:21.780 align:start position:0% what Merkel trees are America Patricia 01:47:21.780 --> 01:47:23.930 align:start position:0% what Merkel trees are America Patricia trees<01:47:22.320> are<01:47:22.500> on<01:47:22.980> ethereum<01:47:23.400> we<01:47:23.520> use<01:47:23.639> Marco 01:47:23.930 --> 01:47:23.940 align:start position:0% trees are on ethereum we use Marco 01:47:23.940 --> 01:47:25.910 align:start position:0% trees are on ethereum we use Marco Patricia<01:47:24.360> trees<01:47:24.719> and<01:47:25.260> essentially<01:47:25.500> there<01:47:25.739> is 01:47:25.910 --> 01:47:25.920 align:start position:0% Patricia trees and essentially there is 01:47:25.920 --> 01:47:27.890 align:start position:0% Patricia trees and essentially there is a<01:47:26.040> trade-off<01:47:26.400> that<01:47:26.820> when<01:47:27.300> using<01:47:27.600> Miracle 01:47:27.890 --> 01:47:27.900 align:start position:0% a trade-off that when using Miracle 01:47:27.900 --> 01:47:29.510 align:start position:0% a trade-off that when using Miracle Patricia<01:47:28.260> trees<01:47:28.440> the<01:47:28.619> proof<01:47:28.800> is<01:47:28.920> a<01:47:29.159> slightly 01:47:29.510 --> 01:47:29.520 align:start position:0% Patricia trees the proof is a slightly 01:47:29.520 --> 01:47:32.990 align:start position:0% Patricia trees the proof is a slightly bigger<01:47:29.880> it's<01:47:30.659> like<01:47:31.080> harder<01:47:31.619> to<01:47:32.100> decode<01:47:32.880> it 01:47:32.990 --> 01:47:33.000 align:start position:0% bigger it's like harder to decode it 01:47:33.000 --> 01:47:34.550 align:start position:0% bigger it's like harder to decode it because<01:47:33.179> actually<01:47:33.360> we<01:47:33.659> need<01:47:33.780> to<01:47:33.840> do<01:47:34.020> some<01:47:34.320> a 01:47:34.550 --> 01:47:34.560 align:start position:0% because actually we need to do some a 01:47:34.560 --> 01:47:36.530 align:start position:0% because actually we need to do some a bit<01:47:34.679> of<01:47:34.860> decoding<01:47:35.280> there 01:47:36.530 --> 01:47:36.540 align:start position:0% bit of decoding there 01:47:36.540 --> 01:47:39.470 align:start position:0% bit of decoding there um<01:47:36.600> but<01:47:37.260> we<01:47:37.619> need<01:47:37.860> to<01:47:37.980> do<01:47:38.159> less<01:47:38.340> hashing<01:47:38.880> so 01:47:39.470 --> 01:47:39.480 align:start position:0% um but we need to do less hashing so 01:47:39.480 --> 01:47:41.510 align:start position:0% um but we need to do less hashing so this<01:47:39.719> is<01:47:39.780> a<01:47:39.960> trade-off<01:47:40.320> but<01:47:40.800> depending<01:47:41.219> where 01:47:41.510 --> 01:47:41.520 align:start position:0% this is a trade-off but depending where 01:47:41.520 --> 01:47:43.490 align:start position:0% this is a trade-off but depending where we<01:47:41.639> actually<01:47:41.760> verify<01:47:42.239> this<01:47:42.360> proof<01:47:42.719> it<01:47:43.320> might 01:47:43.490 --> 01:47:43.500 align:start position:0% we actually verify this proof it might 01:47:43.500 --> 01:47:46.070 align:start position:0% we actually verify this proof it might be<01:47:43.619> more<01:47:43.739> feasible<01:47:44.100> to<01:47:44.280> verify<01:47:44.699> like<01:47:45.659> prove 01:47:46.070 --> 01:47:46.080 align:start position:0% be more feasible to verify like prove 01:47:46.080 --> 01:47:47.330 align:start position:0% be more feasible to verify like prove that<01:47:46.139> is<01:47:46.260> based<01:47:46.440> on<01:47:46.500> record<01:47:46.679> Patricia<01:47:47.040> trees 01:47:47.330 --> 01:47:47.340 align:start position:0% that is based on record Patricia trees 01:47:47.340 --> 01:47:48.649 align:start position:0% that is based on record Patricia trees or<01:47:47.460> Miracle<01:47:47.820> trees 01:47:48.649 --> 01:47:48.659 align:start position:0% or Miracle trees 01:47:48.659 --> 01:47:51.890 align:start position:0% or Miracle trees okay<01:47:49.460> but<01:47:50.460> there<01:47:50.760> is<01:47:50.940> a<01:47:51.000> solution 01:47:51.890 --> 01:47:51.900 align:start position:0% okay but there is a solution 01:47:51.900 --> 01:47:54.890 align:start position:0% okay but there is a solution and<01:47:52.440> the<01:47:52.560> solution<01:47:52.860> is<01:47:53.100> what<01:47:53.520> if<01:47:53.699> we<01:47:53.940> snarkify 01:47:54.890 --> 01:47:54.900 align:start position:0% and the solution is what if we snarkify 01:47:54.900 --> 01:47:57.649 align:start position:0% and the solution is what if we snarkify such<01:47:55.500> such<01:47:55.800> a<01:47:56.040> proof<01:47:56.340> and<01:47:56.940> we<01:47:57.119> verify<01:47:57.480> this 01:47:57.649 --> 01:47:57.659 align:start position:0% such such a proof and we verify this 01:47:57.659 --> 01:47:59.930 align:start position:0% such such a proof and we verify this proof<01:47:57.960> inside<01:47:58.080> the<01:47:58.320> Stark<01:47:59.040> why<01:47:59.460> is<01:47:59.639> it<01:47:59.760> cool 01:47:59.930 --> 01:47:59.940 align:start position:0% proof inside the Stark why is it cool 01:47:59.940 --> 01:48:02.270 align:start position:0% proof inside the Stark why is it cool because<01:48:00.300> we<01:48:01.260> can<01:48:01.440> like<01:48:01.560> let's<01:48:01.800> say<01:48:01.980> that<01:48:02.159> I'm 01:48:02.270 --> 01:48:02.280 align:start position:0% because we can like let's say that I'm 01:48:02.280 --> 01:48:04.609 align:start position:0% because we can like let's say that I'm gonna<01:48:02.400> verify<01:48:02.940> this<01:48:03.119> proof<01:48:03.480> inside<01:48:03.600> the<01:48:03.960> craft 01:48:04.609 --> 01:48:04.619 align:start position:0% gonna verify this proof inside the craft 01:48:04.619 --> 01:48:07.729 align:start position:0% gonna verify this proof inside the craft craft<01:48:04.980> 16<01:48:05.219> circuit 01:48:07.729 --> 01:48:07.739 align:start position:0% craft 16 circuit 01:48:07.739 --> 01:48:09.649 align:start position:0% craft 16 circuit um<01:48:07.800> and<01:48:08.159> yeah<01:48:08.280> the<01:48:08.699> verification<01:48:09.119> costs<01:48:09.600> more 01:48:09.649 --> 01:48:09.659 align:start position:0% um and yeah the verification costs more 01:48:09.659 --> 01:48:13.010 align:start position:0% um and yeah the verification costs more or<01:48:09.840> less<01:48:09.900> like<01:48:10.520> 210k<01:48:11.520> gas<01:48:11.760> the<01:48:12.360> proof<01:48:12.659> is<01:48:12.780> like 01:48:13.010 --> 01:48:13.020 align:start position:0% or less like 210k gas the proof is like 01:48:13.020 --> 01:48:15.950 align:start position:0% or less like 210k gas the proof is like way<01:48:13.320> less<01:48:13.560> than<01:48:13.800> 600<01:48:14.460> bytes<01:48:15.000> so<01:48:15.420> it's<01:48:15.540> good<01:48:15.780> so 01:48:15.950 --> 01:48:15.960 align:start position:0% way less than 600 bytes so it's good so 01:48:15.960 --> 01:48:17.510 align:start position:0% way less than 600 bytes so it's good so essentially<01:48:16.320> get<01:48:16.560> rid<01:48:16.739> of<01:48:16.860> the<01:48:17.040> cold<01:48:17.159> data 01:48:17.510 --> 01:48:17.520 align:start position:0% essentially get rid of the cold data 01:48:17.520 --> 01:48:19.910 align:start position:0% essentially get rid of the cold data because<01:48:17.639> the<01:48:17.880> proof<01:48:18.060> itself<01:48:18.360> can<01:48:18.659> be<01:48:18.780> the 01:48:19.910 --> 01:48:19.920 align:start position:0% because the proof itself can be the 01:48:19.920 --> 01:48:22.729 align:start position:0% because the proof itself can be the private<01:48:20.639> input<01:48:20.880> to<01:48:21.060> the<01:48:21.239> Circuit 01:48:22.729 --> 01:48:22.739 align:start position:0% private input to the Circuit 01:48:22.739 --> 01:48:25.310 align:start position:0% private input to the Circuit um yeah<01:48:23.219> we<01:48:23.639> can<01:48:23.760> like<01:48:23.940> use<01:48:24.239> multiple<01:48:24.900> proving 01:48:25.310 --> 01:48:25.320 align:start position:0% um yeah we can like use multiple proving 01:48:25.320 --> 01:48:27.229 align:start position:0% um yeah we can like use multiple proving system<01:48:25.500> depending<01:48:26.040> on<01:48:26.280> the<01:48:26.460> on<01:48:26.880> the<01:48:27.060> actual 01:48:27.229 --> 01:48:27.239 align:start position:0% system depending on the on the actual 01:48:27.239 --> 01:48:30.169 align:start position:0% system depending on the on the actual use<01:48:27.480> case<01:48:27.780> and<01:48:28.440> now<01:48:28.619> why<01:48:28.980> is<01:48:29.280> it<01:48:29.460> like<01:48:29.880> very 01:48:30.169 --> 01:48:30.179 align:start position:0% use case and now why is it like very 01:48:30.179 --> 01:48:31.970 align:start position:0% use case and now why is it like very very<01:48:30.360> cool<01:48:30.600> so<01:48:30.900> first<01:48:31.020> of<01:48:31.199> all<01:48:31.260> it<01:48:31.619> removes 01:48:31.970 --> 01:48:31.980 align:start position:0% very cool so first of all it removes 01:48:31.980 --> 01:48:33.410 align:start position:0% very cool so first of all it removes call<01:48:32.159> data 01:48:33.410 --> 01:48:33.420 align:start position:0% call data 01:48:33.420 --> 01:48:36.109 align:start position:0% call data second<01:48:33.840> model<01:48:34.139> it<01:48:34.920> allows<01:48:35.219> us<01:48:35.340> to<01:48:35.580> deal<01:48:35.820> with 01:48:36.109 --> 01:48:36.119 align:start position:0% second model it allows us to deal with 01:48:36.119 --> 01:48:38.930 align:start position:0% second model it allows us to deal with very<01:48:36.480> UNH<01:48:36.960> unfriendly<01:48:37.560> hashing<01:48:37.980> functions<01:48:38.460> or 01:48:38.930 --> 01:48:38.940 align:start position:0% very UNH unfriendly hashing functions or 01:48:38.940 --> 01:48:41.750 align:start position:0% very UNH unfriendly hashing functions or the<01:48:39.119> evm<01:48:39.540> is<01:48:40.260> the<01:48:40.619> ones<01:48:40.860> that<01:48:41.100> we<01:48:41.460> don't<01:48:41.580> have 01:48:41.750 --> 01:48:41.760 align:start position:0% the evm is the ones that we don't have 01:48:41.760 --> 01:48:45.830 align:start position:0% the evm is the ones that we don't have pre-compiled<01:48:42.420> for<01:48:42.540> like<01:48:43.199> let's<01:48:43.500> say<01:48:43.679> Peterson 01:48:45.830 --> 01:48:45.840 align:start position:0% pre-compiled for like let's say Peterson 01:48:45.840 --> 01:48:48.169 align:start position:0% pre-compiled for like let's say Peterson um<01:48:46.040> so<01:48:47.040> it<01:48:47.159> might<01:48:47.280> be<01:48:47.400> like<01:48:47.580> super<01:48:47.760> expensive 01:48:48.169 --> 01:48:48.179 align:start position:0% um so it might be like super expensive 01:48:48.179 --> 01:48:49.790 align:start position:0% um so it might be like super expensive to<01:48:48.420> verify<01:48:48.659> such<01:48:48.900> a<01:48:49.080> proof<01:48:49.260> on<01:48:49.380> the<01:48:49.440> evm 01:48:49.790 --> 01:48:49.800 align:start position:0% to verify such a proof on the evm 01:48:49.800 --> 01:48:50.930 align:start position:0% to verify such a proof on the evm because<01:48:49.980> first<01:48:50.159> of<01:48:50.340> all<01:48:50.400> that's<01:48:50.580> a<01:48:50.760> lot<01:48:50.820> of 01:48:50.930 --> 01:48:50.940 align:start position:0% because first of all that's a lot of 01:48:50.940 --> 01:48:52.850 align:start position:0% because first of all that's a lot of cool<01:48:51.060> data<01:48:51.480> and<01:48:51.900> the<01:48:52.020> hashing<01:48:52.380> function<01:48:52.679> is 01:48:52.850 --> 01:48:52.860 align:start position:0% cool data and the hashing function is 01:48:52.860 --> 01:48:55.070 align:start position:0% cool data and the hashing function is pretty<01:48:53.040> like<01:48:53.219> unfriendly<01:48:53.820> but<01:48:54.420> what<01:48:54.719> if<01:48:54.900> we 01:48:55.070 --> 01:48:55.080 align:start position:0% pretty like unfriendly but what if we 01:48:55.080 --> 01:48:56.810 align:start position:0% pretty like unfriendly but what if we can<01:48:55.260> like<01:48:55.440> do<01:48:55.800> it<01:48:55.920> inside<01:48:56.040> the<01:48:56.280> snark<01:48:56.520> and<01:48:56.699> just 01:48:56.810 --> 01:48:56.820 align:start position:0% can like do it inside the snark and just 01:48:56.820 --> 01:49:00.050 align:start position:0% can like do it inside the snark and just verify<01:48:57.119> snark<01:48:57.619> and<01:48:58.619> yeah<01:48:58.980> so<01:48:59.639> another 01:49:00.050 --> 01:49:00.060 align:start position:0% verify snark and yeah so another 01:49:00.060 --> 01:49:02.990 align:start position:0% verify snark and yeah so another benefits<01:49:00.900> this<01:49:01.619> really<01:49:02.040> really<01:49:02.340> helps<01:49:02.820> in 01:49:02.990 --> 01:49:03.000 align:start position:0% benefits this really really helps in 01:49:03.000 --> 01:49:05.209 align:start position:0% benefits this really really helps in obstructing<01:49:03.600> the<01:49:03.840> way<01:49:04.020> how<01:49:04.500> we<01:49:04.739> verify<01:49:05.100> this 01:49:05.209 --> 01:49:05.219 align:start position:0% obstructing the way how we verify this 01:49:05.219 --> 01:49:06.709 align:start position:0% obstructing the way how we verify this proofs<01:49:05.639> because<01:49:05.940> you<01:49:06.179> don't<01:49:06.300> need<01:49:06.480> to<01:49:06.600> have 01:49:06.709 --> 01:49:06.719 align:start position:0% proofs because you don't need to have 01:49:06.719 --> 01:49:09.590 align:start position:0% proofs because you don't need to have like<01:49:06.960> one<01:49:07.260> generalized<01:49:07.860> verifier<01:49:08.340> for<01:49:09.179> each 01:49:09.590 --> 01:49:09.600 align:start position:0% like one generalized verifier for each 01:49:09.600 --> 01:49:12.070 align:start position:0% like one generalized verifier for each type<01:49:09.960> of<01:49:10.440> of<01:49:10.679> proof 01:49:12.070 --> 01:49:12.080 align:start position:0% type of of proof 01:49:12.080 --> 01:49:14.390 align:start position:0% type of of proof but<01:49:13.080> you<01:49:13.320> can<01:49:13.440> essentially<01:49:13.800> obstruct<01:49:14.159> it 01:49:14.390 --> 01:49:14.400 align:start position:0% but you can essentially obstruct it 01:49:14.400 --> 01:49:17.090 align:start position:0% but you can essentially obstruct it behind<01:49:14.760> behind<01:49:15.420> the<01:49:15.540> behind<01:49:15.960> the<01:49:16.020> snark<01:49:16.320> which 01:49:17.090 --> 01:49:17.100 align:start position:0% behind behind the behind the snark which 01:49:17.100 --> 01:49:19.729 align:start position:0% behind behind the behind the snark which is<01:49:17.219> which<01:49:17.520> is<01:49:17.760> great<01:49:17.940> uh<01:49:18.900> these<01:49:19.199> numbers<01:49:19.320> were 01:49:19.729 --> 01:49:19.739 align:start position:0% is which is great uh these numbers were 01:49:19.739 --> 01:49:23.689 align:start position:0% is which is great uh these numbers were taken<01:49:20.219> from<01:49:20.460> a<01:49:20.820> very<01:49:21.000> nice<01:49:21.800> article<01:49:22.800> written 01:49:23.689 --> 01:49:23.699 align:start position:0% taken from a very nice article written 01:49:23.699 --> 01:49:26.870 align:start position:0% taken from a very nice article written by<01:49:24.000> a16z<01:49:24.840> like<01:49:25.199> a<01:49:25.320> bunch<01:49:25.560> of<01:49:25.739> uh<01:49:26.219> a<01:49:26.460> few<01:49:26.520> a<01:49:26.699> few 01:49:26.870 --> 01:49:26.880 align:start position:0% by a16z like a bunch of uh a few a few 01:49:26.880 --> 01:49:28.430 align:start position:0% by a16z like a bunch of uh a few a few months<01:49:27.060> ago 01:49:28.430 --> 01:49:28.440 align:start position:0% months ago 01:49:28.440 --> 01:49:30.709 align:start position:0% months ago um<01:49:28.560> yeah<01:49:29.219> and<01:49:29.400> I<01:49:29.520> think<01:49:29.699> that's<01:49:29.940> pretty<01:49:30.480> much 01:49:30.709 --> 01:49:30.719 align:start position:0% um yeah and I think that's pretty much 01:49:30.719 --> 01:49:34.310 align:start position:0% um yeah and I think that's pretty much it<01:49:31.020> let's<01:49:31.320> get<01:49:31.619> to<01:49:31.739> the<01:49:31.920> next<01:49:32.159> slide<01:49:32.520> so 01:49:34.310 --> 01:49:34.320 align:start position:0% it let's get to the next slide so 01:49:34.320 --> 01:49:37.010 align:start position:0% it let's get to the next slide so synchronous<01:49:35.100> cross<01:49:35.280> layer<01:49:35.639> State<01:49:35.820> access<01:49:36.179> so 01:49:37.010 --> 01:49:37.020 align:start position:0% synchronous cross layer State access so 01:49:37.020 --> 01:49:38.930 align:start position:0% synchronous cross layer State access so how<01:49:37.199> can<01:49:37.380> actually<01:49:37.560> a<01:49:37.920> control<01:49:38.040> deployed<01:49:38.639> on 01:49:38.930 --> 01:49:38.940 align:start position:0% how can actually a control deployed on 01:49:38.940 --> 01:49:41.270 align:start position:0% how can actually a control deployed on some<01:49:39.420> layer<01:49:39.780> access<01:49:40.139> the<01:49:40.500> state<01:49:40.679> of<01:49:40.920> another 01:49:41.270 --> 01:49:41.280 align:start position:0% some layer access the state of another 01:49:41.280 --> 01:49:43.669 align:start position:0% some layer access the state of another L2<01:49:42.000> or<01:49:42.179> L1 01:49:43.669 --> 01:49:43.679 align:start position:0% L2 or L1 01:49:43.679 --> 01:49:46.669 align:start position:0% L2 or L1 so<01:49:44.400> I<01:49:44.699> mentioned<01:49:45.060> that<01:49:45.360> we<01:49:45.900> always<01:49:46.080> need<01:49:46.500> the 01:49:46.669 --> 01:49:46.679 align:start position:0% so I mentioned that we always need the 01:49:46.679 --> 01:49:48.649 align:start position:0% so I mentioned that we always need the state<01:49:46.860> route<01:49:47.100> but<01:49:47.580> because<01:49:47.880> all<01:49:48.239> of<01:49:48.420> these 01:49:48.649 --> 01:49:48.659 align:start position:0% state route but because all of these 01:49:48.659 --> 01:49:50.990 align:start position:0% state route but because all of these systems<01:49:49.139> have<01:49:49.619> a<01:49:49.920> native<01:49:50.280> messaging<01:49:50.820> system 01:49:50.990 --> 01:49:51.000 align:start position:0% systems have a native messaging system 01:49:51.000 --> 01:49:53.090 align:start position:0% systems have a native messaging system we<01:49:51.719> can<01:49:51.840> send<01:49:52.020> the<01:49:52.199> small<01:49:52.380> commitments<01:49:52.980> like 01:49:53.090 --> 01:49:53.100 align:start position:0% we can send the small commitments like 01:49:53.100 --> 01:49:55.669 align:start position:0% we can send the small commitments like for<01:49:53.280> example<01:49:53.520> the<01:49:53.760> blockage<01:49:54.119> to<01:49:54.960> like<01:49:55.199> L1 01:49:55.669 --> 01:49:55.679 align:start position:0% for example the blockage to like L1 01:49:55.679 --> 01:49:58.910 align:start position:0% for example the blockage to like L1 usually<01:49:56.639> it<01:49:57.000> goes<01:49:57.300> off-road<01:49:57.780> one<01:49:58.020> and<01:49:58.679> and 01:49:58.910 --> 01:49:58.920 align:start position:0% usually it goes off-road one and and 01:49:58.920 --> 01:50:00.709 align:start position:0% usually it goes off-road one and and yeah<01:49:59.100> we<01:49:59.340> can<01:49:59.460> like<01:49:59.580> enroll<01:50:00.000> it<01:50:00.179> or<01:50:00.360> send<01:50:00.540> the 01:50:00.709 --> 01:50:00.719 align:start position:0% yeah we can like enroll it or send the 01:50:00.719 --> 01:50:02.390 align:start position:0% yeah we can like enroll it or send the state<01:50:00.840> through<01:50:01.080> directly<01:50:01.440> and<01:50:01.920> also<01:50:02.100> we<01:50:02.280> don't 01:50:02.390 --> 01:50:02.400 align:start position:0% state through directly and also we don't 01:50:02.400 --> 01:50:04.310 align:start position:0% state through directly and also we don't need<01:50:02.580> to<01:50:02.760> rely<01:50:03.060> on<01:50:03.179> messaging<01:50:03.540> but<01:50:03.780> we<01:50:03.960> can<01:50:04.080> for 01:50:04.310 --> 01:50:04.320 align:start position:0% need to rely on messaging but we can for 01:50:04.320 --> 01:50:07.010 align:start position:0% need to rely on messaging but we can for example<01:50:04.619> uh<01:50:05.460> rely<01:50:05.760> on<01:50:05.880> the<01:50:06.000> fact<01:50:06.179> that<01:50:06.420> polygon 01:50:07.010 --> 01:50:07.020 align:start position:0% example uh rely on the fact that polygon 01:50:07.020 --> 01:50:09.050 align:start position:0% example uh rely on the fact that polygon is<01:50:07.199> like<01:50:07.380> a<01:50:07.560> commit<01:50:07.860> chain<01:50:08.040> and<01:50:08.340> all<01:50:08.820> these 01:50:09.050 --> 01:50:09.060 align:start position:0% is like a commit chain and all these 01:50:09.060 --> 01:50:11.090 align:start position:0% is like a commit chain and all these Roll-Ups<01:50:09.600> like<01:50:09.719> commit<01:50:10.080> from<01:50:10.560> time<01:50:10.739> to<01:50:10.920> time 01:50:11.090 --> 01:50:11.100 align:start position:0% Roll-Ups like commit from time to time 01:50:11.100 --> 01:50:14.570 align:start position:0% Roll-Ups like commit from time to time they're<01:50:11.460> like<01:50:11.840> batches<01:50:12.840> and<01:50:13.500> and<01:50:13.679> so<01:50:13.920> on<01:50:14.040> so 01:50:14.570 --> 01:50:14.580 align:start position:0% they're like batches and and so on so 01:50:14.580 --> 01:50:16.070 align:start position:0% they're like batches and and so on so this<01:50:14.760> is<01:50:14.880> like<01:50:15.000> pretty<01:50:15.239> important<01:50:15.659> and<01:50:15.840> we 01:50:16.070 --> 01:50:16.080 align:start position:0% this is like pretty important and we 01:50:16.080 --> 01:50:18.350 align:start position:0% this is like pretty important and we sort<01:50:16.560> of<01:50:16.679> can<01:50:16.920> get<01:50:17.159> the<01:50:17.400> commitment<01:50:17.820> from 01:50:18.350 --> 01:50:18.360 align:start position:0% sort of can get the commitment from 01:50:18.360 --> 01:50:20.930 align:start position:0% sort of can get the commitment from which<01:50:18.600> we'll<01:50:18.840> recreate<01:50:19.440> the<01:50:19.560> state<01:50:19.940> directly 01:50:20.930 --> 01:50:20.940 align:start position:0% which we'll recreate the state directly 01:50:20.940 --> 01:50:22.609 align:start position:0% which we'll recreate the state directly on<01:50:21.179> on<01:50:21.360> another<01:50:21.600> one<01:50:21.900> and<01:50:22.020> then<01:50:22.139> send<01:50:22.320> it<01:50:22.500> to 01:50:22.609 --> 01:50:22.619 align:start position:0% on on another one and then send it to 01:50:22.619 --> 01:50:24.649 align:start position:0% on on another one and then send it to another 01:50:24.649 --> 01:50:24.659 align:start position:0% another 01:50:24.659 --> 01:50:27.229 align:start position:0% another um so<01:50:25.340> if 01:50:27.229 --> 01:50:27.239 align:start position:0% um so if 01:50:27.239 --> 01:50:29.810 align:start position:0% um so if let's<01:50:27.840> say<01:50:28.020> polygon<01:50:28.500> commits<01:50:28.980> another<01:50:29.219> one<01:50:29.580> I 01:50:29.810 --> 01:50:29.820 align:start position:0% let's say polygon commits another one I 01:50:29.820 --> 01:50:31.310 align:start position:0% let's say polygon commits another one I can<01:50:30.000> send<01:50:30.119> this<01:50:30.360> commitment<01:50:30.780> then<01:50:31.020> to<01:50:31.199> start 01:50:31.310 --> 01:50:31.320 align:start position:0% can send this commitment then to start 01:50:31.320 --> 01:50:32.629 align:start position:0% can send this commitment then to start and<01:50:31.619> I'm<01:50:31.800> starting<01:50:31.920> to<01:50:32.159> do<01:50:32.280> their<01:50:32.460> actual 01:50:32.629 --> 01:50:32.639 align:start position:0% and I'm starting to do their actual 01:50:32.639 --> 01:50:34.370 align:start position:0% and I'm starting to do their actual verification 01:50:34.370 --> 01:50:34.380 align:start position:0% verification 01:50:34.380 --> 01:50:37.910 align:start position:0% verification cool<01:50:34.860> so<01:50:35.580> now<01:50:35.900> how<01:50:36.900> do<01:50:37.020> we<01:50:37.199> actually<01:50:37.440> do<01:50:37.739> that 01:50:37.910 --> 01:50:37.920 align:start position:0% cool so now how do we actually do that 01:50:37.920 --> 01:50:40.010 align:start position:0% cool so now how do we actually do that so<01:50:38.219> let's<01:50:38.400> break<01:50:38.699> the<01:50:38.880> entire<01:50:39.119> flow<01:50:39.540> into<01:50:39.719> like 01:50:40.010 --> 01:50:40.020 align:start position:0% so let's break the entire flow into like 01:50:40.020 --> 01:50:41.330 align:start position:0% so let's break the entire flow into like smallest<01:50:40.500> pieces 01:50:41.330 --> 01:50:41.340 align:start position:0% smallest pieces 01:50:41.340 --> 01:50:43.189 align:start position:0% smallest pieces so<01:50:41.699> the<01:50:41.820> flow<01:50:42.000> is<01:50:42.239> the<01:50:42.360> following<01:50:42.659> we<01:50:42.900> need<01:50:43.080> to 01:50:43.189 --> 01:50:43.199 align:start position:0% so the flow is the following we need to 01:50:43.199 --> 01:50:45.229 align:start position:0% so the flow is the following we need to have<01:50:43.380> access<01:50:43.619> to<01:50:43.920> the<01:50:44.040> commitment<01:50:44.520> which<01:50:45.060> is 01:50:45.229 --> 01:50:45.239 align:start position:0% have access to the commitment which is 01:50:45.239 --> 01:50:47.390 align:start position:0% have access to the commitment which is either<01:50:45.480> a<01:50:45.780> block<01:50:45.900> hush<01:50:46.260> or<01:50:46.380> a<01:50:46.500> state<01:50:46.619> route 01:50:47.390 --> 01:50:47.400 align:start position:0% either a block hush or a state route 01:50:47.400 --> 01:50:50.149 align:start position:0% either a block hush or a state route and<01:50:47.940> again<01:50:48.239> we<01:50:48.480> can<01:50:48.600> get<01:50:48.780> it<01:50:48.900> or<01:50:49.260> I<01:50:49.500> either<01:50:49.860> by 01:50:50.149 --> 01:50:50.159 align:start position:0% and again we can get it or I either by 01:50:50.159 --> 01:50:52.310 align:start position:0% and again we can get it or I either by sending<01:50:50.520> a<01:50:50.639> message<01:50:50.900> relying<01:50:51.900> on<01:50:52.020> the<01:50:52.139> fact 01:50:52.310 --> 01:50:52.320 align:start position:0% sending a message relying on the fact 01:50:52.320 --> 01:50:53.090 align:start position:0% sending a message relying on the fact that 01:50:53.090 --> 01:50:53.100 align:start position:0% that 01:50:53.100 --> 01:50:55.609 align:start position:0% that is<01:50:53.760> this<01:50:54.000> chain<01:50:54.119> commit<01:50:54.540> so<01:50:54.780> in<01:50:55.080> a<01:50:55.199> sense<01:50:55.320> it's 01:50:55.609 --> 01:50:55.619 align:start position:0% is this chain commit so in a sense it's 01:50:55.619 --> 01:50:57.709 align:start position:0% is this chain commit so in a sense it's still<01:50:55.800> a<01:50:56.040> message<01:50:56.219> we<01:50:56.940> can<01:50:57.119> relate<01:50:57.480> in<01:50:57.659> an 01:50:57.709 --> 01:50:57.719 align:start position:0% still a message we can relate in an 01:50:57.719 --> 01:51:00.350 align:start position:0% still a message we can relate in an optimistic<01:50:58.199> manner<01:50:58.560> or<01:50:59.159> we<01:50:59.520> can<01:50:59.639> go<01:50:59.880> even<01:51:00.119> more 01:51:00.350 --> 01:51:00.360 align:start position:0% optimistic manner or we can go even more 01:51:00.360 --> 01:51:03.470 align:start position:0% optimistic manner or we can go even more crazy<01:51:00.600> and<01:51:00.900> verify<01:51:01.260> the<01:51:01.380> entire<01:51:01.619> consensus 01:51:03.470 --> 01:51:03.480 align:start position:0% crazy and verify the entire consensus 01:51:03.480 --> 01:51:05.750 align:start position:0% crazy and verify the entire consensus okay<01:51:04.020> so<01:51:04.440> this<01:51:04.560> is<01:51:04.679> Step<01:51:04.920> number<01:51:05.100> one<01:51:05.340> we<01:51:05.639> need 01:51:05.750 --> 01:51:05.760 align:start position:0% okay so this is Step number one we need 01:51:05.760 --> 01:51:08.390 align:start position:0% okay so this is Step number one we need to<01:51:05.880> get<01:51:06.000> the<01:51:06.179> commitment<01:51:06.540> step<01:51:07.020> number<01:51:07.260> two<01:51:07.560> we 01:51:08.390 --> 01:51:08.400 align:start position:0% to get the commitment step number two we 01:51:08.400 --> 01:51:10.370 align:start position:0% to get the commitment step number two we need<01:51:08.580> to<01:51:08.880> somehow<01:51:09.300> access<01:51:09.600> the<01:51:09.960> state<01:51:10.139> route 01:51:10.370 --> 01:51:10.380 align:start position:0% need to somehow access the state route 01:51:10.380 --> 01:51:12.410 align:start position:0% need to somehow access the state route so<01:51:10.619> the<01:51:10.739> commitments<01:51:11.219> of<01:51:11.340> the<01:51:11.520> state<01:51:11.699> from 01:51:12.410 --> 01:51:12.420 align:start position:0% so the commitments of the state from 01:51:12.420 --> 01:51:14.149 align:start position:0% so the commitments of the state from like<01:51:12.659> a<01:51:12.780> previous<01:51:12.960> block<01:51:13.260> or<01:51:13.500> the<01:51:13.679> actual<01:51:13.920> blog 01:51:14.149 --> 01:51:14.159 align:start position:0% like a previous block or the actual blog 01:51:14.159 --> 01:51:15.229 align:start position:0% like a previous block or the actual blog because<01:51:14.340> keep<01:51:14.639> in<01:51:14.760> mind<01:51:14.880> that<01:51:15.060> these 01:51:15.229 --> 01:51:15.239 align:start position:0% because keep in mind that these 01:51:15.239 --> 01:51:17.270 align:start position:0% because keep in mind that these commitments<01:51:15.719> are<01:51:15.840> only<01:51:16.080> block<01:51:16.380> hashes<01:51:16.920> and 01:51:17.270 --> 01:51:17.280 align:start position:0% commitments are only block hashes and 01:51:17.280 --> 01:51:18.709 align:start position:0% commitments are only block hashes and with<01:51:17.460> block<01:51:17.639> hashes<01:51:18.000> we<01:51:18.179> can<01:51:18.300> recreate 01:51:18.709 --> 01:51:18.719 align:start position:0% with block hashes we can recreate 01:51:18.719 --> 01:51:22.129 align:start position:0% with block hashes we can recreate headers<01:51:19.080> but<01:51:19.320> we<01:51:19.500> cannot<01:51:19.980> access<01:51:20.159> the<01:51:20.460> state 01:51:22.129 --> 01:51:22.139 align:start position:0% headers but we cannot access the state 01:51:22.139 --> 01:51:24.830 align:start position:0% headers but we cannot access the state okay<01:51:22.560> so<01:51:23.100> once<01:51:23.639> we<01:51:23.699> have<01:51:23.820> the<01:51:24.000> state<01:51:24.119> route<01:51:24.420> we 01:51:24.830 --> 01:51:24.840 align:start position:0% okay so once we have the state route we 01:51:24.840 --> 01:51:27.350 align:start position:0% okay so once we have the state route we obviously<01:51:25.139> need<01:51:25.320> to<01:51:25.500> verify<01:51:25.980> this<01:51:26.520> state 01:51:27.350 --> 01:51:27.360 align:start position:0% obviously need to verify this state 01:51:27.360 --> 01:51:30.649 align:start position:0% obviously need to verify this state storage<01:51:28.199> groups<01:51:29.159> okay<01:51:29.760> and<01:51:30.239> there<01:51:30.480> are 01:51:30.649 --> 01:51:30.659 align:start position:0% storage groups okay and there are 01:51:30.659 --> 01:51:33.050 align:start position:0% storage groups okay and there are multiple<01:51:31.080> pictures<01:51:31.440> to<01:51:31.860> do<01:51:31.980> that<01:51:32.159> all<01:51:32.760> of<01:51:32.940> them 01:51:33.050 --> 01:51:33.060 align:start position:0% multiple pictures to do that all of them 01:51:33.060 --> 01:51:35.330 align:start position:0% multiple pictures to do that all of them come<01:51:33.300> with<01:51:33.480> some<01:51:33.659> trade-offs<01:51:34.199> and<01:51:34.679> let's<01:51:34.980> go 01:51:35.330 --> 01:51:35.340 align:start position:0% come with some trade-offs and let's go 01:51:35.340 --> 01:51:38.570 align:start position:0% come with some trade-offs and let's go through<01:51:35.639> all<01:51:36.060> these<01:51:36.239> approaches 01:51:38.570 --> 01:51:38.580 align:start position:0% through all these approaches 01:51:38.580 --> 01:51:42.169 align:start position:0% through all these approaches so<01:51:39.360> approach<01:51:40.020> number<01:51:40.320> one<01:51:40.679> messaging 01:51:42.169 --> 01:51:42.179 align:start position:0% so approach number one messaging 01:51:42.179 --> 01:51:47.990 align:start position:0% so approach number one messaging so<01:51:43.139> I<01:51:43.920> can<01:51:44.040> send<01:51:44.280> the<01:51:44.580> message<01:51:44.820> from<01:51:45.540> let's<01:51:45.960> say 01:51:47.990 --> 01:51:48.000 align:start position:0% so I can send the message from let's say 01:51:48.000 --> 01:51:50.629 align:start position:0% so I can send the message from let's say optimism<01:51:48.920> to 01:51:50.629 --> 01:51:50.639 align:start position:0% optimism to 01:51:50.639 --> 01:51:53.390 align:start position:0% optimism to Eternal<01:51:50.940> one<01:51:51.239> I<01:51:51.900> can<01:51:52.020> get<01:51:52.199> the<01:51:52.380> optical<01:51:52.800> I<01:51:53.100> can 01:51:53.390 --> 01:51:53.400 align:start position:0% Eternal one I can get the optical I can 01:51:53.400 --> 01:51:54.770 align:start position:0% Eternal one I can get the optical I can get<01:51:53.520> the<01:51:53.639> blockers<01:51:54.000> by<01:51:54.119> just<01:51:54.360> calling<01:51:54.600> the 01:51:54.770 --> 01:51:54.780 align:start position:0% get the blockers by just calling the 01:51:54.780 --> 01:51:58.310 align:start position:0% get the blockers by just calling the proper<01:51:55.020> op<01:51:55.199> code<01:51:55.580> and<01:51:56.580> and<01:51:57.000> I<01:51:57.239> get<01:51:57.600> it<01:51:57.780> take 01:51:58.310 --> 01:51:58.320 align:start position:0% proper op code and and I get it take 01:51:58.320 --> 01:52:00.649 align:start position:0% proper op code and and I get it take some<01:51:58.500> time<01:51:58.679> but<01:51:59.100> still<01:51:59.340> I<01:51:59.639> get<01:51:59.760> it<01:51:59.940> this<01:52:00.480> is 01:52:00.649 --> 01:52:00.659 align:start position:0% some time but still I get it this is 01:52:00.659 --> 01:52:02.990 align:start position:0% some time but still I get it this is approach<01:52:00.960> number<01:52:01.139> one<01:52:01.380> so<01:52:02.040> we<01:52:02.400> rely<01:52:02.699> on<01:52:02.880> the 01:52:02.990 --> 01:52:03.000 align:start position:0% approach number one so we rely on the 01:52:03.000 --> 01:52:05.330 align:start position:0% approach number one so we rely on the built-in<01:52:03.300> messaging<01:52:03.719> system<01:52:03.900> which<01:52:04.860> is<01:52:05.040> I 01:52:05.330 --> 01:52:05.340 align:start position:0% built-in messaging system which is I 01:52:05.340 --> 01:52:07.430 align:start position:0% built-in messaging system which is I think<01:52:05.460> Fair<01:52:05.820> because<01:52:06.179> the<01:52:06.600> security<01:52:06.780> of<01:52:07.139> it<01:52:07.260> is 01:52:07.430 --> 01:52:07.440 align:start position:0% think Fair because the security of it is 01:52:07.440 --> 01:52:09.410 align:start position:0% think Fair because the security of it is equal<01:52:07.679> to<01:52:07.920> the<01:52:08.100> security<01:52:08.219> of<01:52:08.580> the<01:52:08.699> roll<01:52:08.820> up<01:52:09.000> and 01:52:09.410 --> 01:52:09.420 align:start position:0% equal to the security of the roll up and 01:52:09.420 --> 01:52:10.729 align:start position:0% equal to the security of the roll up and if<01:52:09.540> you're<01:52:09.659> deploying<01:52:10.080> an<01:52:10.139> application<01:52:10.500> of 01:52:10.729 --> 01:52:10.739 align:start position:0% if you're deploying an application of 01:52:10.739 --> 01:52:13.129 align:start position:0% if you're deploying an application of the<01:52:10.860> scroll<01:52:11.040> up<01:52:11.280> it's<01:52:11.760> a<01:52:11.940> fair<01:52:12.060> assumption<01:52:12.780> to 01:52:13.129 --> 01:52:13.139 align:start position:0% the scroll up it's a fair assumption to 01:52:13.139 --> 01:52:14.990 align:start position:0% the scroll up it's a fair assumption to do<01:52:13.260> so 01:52:14.990 --> 01:52:15.000 align:start position:0% do so 01:52:15.000 --> 01:52:18.109 align:start position:0% do so um<01:52:15.020> yeah<01:52:16.020> it<01:52:16.679> doesn't<01:52:16.920> oh<01:52:17.580> they<01:52:17.820> don't<01:52:17.940> know 01:52:18.109 --> 01:52:18.119 align:start position:0% um yeah it doesn't oh they don't know 01:52:18.119 --> 01:52:20.330 align:start position:0% um yeah it doesn't oh they don't know about<01:52:18.300> the<01:52:18.540> downsides<01:52:19.080> so<01:52:19.619> the<01:52:19.920> message<01:52:20.040> must 01:52:20.330 --> 01:52:20.340 align:start position:0% about the downsides so the message must 01:52:20.340 --> 01:52:21.950 align:start position:0% about the downsides so the message must be<01:52:20.520> delivered<01:52:20.820> so<01:52:21.000> it<01:52:21.179> introduces<01:52:21.719> a 01:52:21.950 --> 01:52:21.960 align:start position:0% be delivered so it introduces a 01:52:21.960 --> 01:52:24.290 align:start position:0% be delivered so it introduces a significant<01:52:22.380> delay<01:52:22.880> especially<01:52:23.880> when 01:52:24.290 --> 01:52:24.300 align:start position:0% significant delay especially when 01:52:24.300 --> 01:52:25.970 align:start position:0% significant delay especially when dealing<01:52:24.719> with<01:52:24.780> the<01:52:24.960> withdrawal<01:52:25.440> period<01:52:25.739> in 01:52:25.970 --> 01:52:25.980 align:start position:0% dealing with the withdrawal period in 01:52:25.980 --> 01:52:28.609 align:start position:0% dealing with the withdrawal period in the<01:52:26.100> in<01:52:26.280> in<01:52:26.460> the<01:52:26.699> middle<01:52:26.820> uh<01:52:27.780> and<01:52:28.020> it<01:52:28.199> requires 01:52:28.609 --> 01:52:28.619 align:start position:0% the in in the middle uh and it requires 01:52:28.619 --> 01:52:31.250 align:start position:0% the in in the middle uh and it requires we<01:52:28.980> it<01:52:29.699> requires<01:52:30.179> interacting<01:52:30.719> with<01:52:30.840> multiple 01:52:31.250 --> 01:52:31.260 align:start position:0% we it requires interacting with multiple 01:52:31.260 --> 01:52:32.689 align:start position:0% we it requires interacting with multiple layers<01:52:31.619> so<01:52:31.800> first<01:52:31.980> you<01:52:32.159> need<01:52:32.340> to<01:52:32.400> send<01:52:32.520> a 01:52:32.689 --> 01:52:32.699 align:start position:0% layers so first you need to send a 01:52:32.699 --> 01:52:33.770 align:start position:0% layers so first you need to send a message<01:52:32.820> and<01:52:33.060> then<01:52:33.179> actually<01:52:33.360> you<01:52:33.540> need<01:52:33.659> to 01:52:33.770 --> 01:52:33.780 align:start position:0% message and then actually you need to 01:52:33.780 --> 01:52:34.910 align:start position:0% message and then actually you need to consume<01:52:34.260> it 01:52:34.910 --> 01:52:34.920 align:start position:0% consume it 01:52:34.920 --> 01:52:36.590 align:start position:0% consume it so<01:52:35.520> it's 01:52:36.590 --> 01:52:36.600 align:start position:0% so it's 01:52:36.600 --> 01:52:39.109 align:start position:0% so it's it's<01:52:36.659> not<01:52:37.260> ideal 01:52:39.109 --> 01:52:39.119 align:start position:0% it's not ideal 01:52:39.119 --> 01:52:41.750 align:start position:0% it's not ideal but<01:52:39.840> the<01:52:40.260> trust<01:52:40.560> assumptions<01:52:40.980> are<01:52:41.340> pretty 01:52:41.750 --> 01:52:41.760 align:start position:0% but the trust assumptions are pretty 01:52:41.760 --> 01:52:44.090 align:start position:0% but the trust assumptions are pretty occasional 01:52:44.090 --> 01:52:44.100 align:start position:0% occasional 01:52:44.100 --> 01:52:47.209 align:start position:0% occasional another<01:52:44.639> approach<01:52:45.179> consensus<01:52:45.960> validation 01:52:47.209 --> 01:52:47.219 align:start position:0% another approach consensus validation 01:52:47.219 --> 01:52:49.850 align:start position:0% another approach consensus validation by<01:52:47.820> the<01:52:47.940> way<01:52:48.000> this<01:52:48.480> like<01:52:48.780> Gremlin<01:52:49.380> is<01:52:49.679> supposed 01:52:49.850 --> 01:52:49.860 align:start position:0% by the way this like Gremlin is supposed 01:52:49.860 --> 01:52:52.609 align:start position:0% by the way this like Gremlin is supposed to<01:52:50.040> verify<01:52:50.460> a<01:52:50.699> bunch<01:52:50.820> of<01:52:50.940> BLS<01:52:51.420> signatures<01:52:51.960> I<01:52:52.380> I 01:52:52.609 --> 01:52:52.619 align:start position:0% to verify a bunch of BLS signatures I I 01:52:52.619 --> 01:52:56.330 align:start position:0% to verify a bunch of BLS signatures I I hope<01:52:52.920> it's<01:52:53.840> self-explanatory<01:52:54.840> uh<01:52:55.800> okay<01:52:55.980> so 01:52:56.330 --> 01:52:56.340 align:start position:0% hope it's self-explanatory uh okay so 01:52:56.340 --> 01:52:59.450 align:start position:0% hope it's self-explanatory uh okay so maybe<01:52:56.820> a<01:52:57.179> few<01:52:57.360> a<01:52:57.780> bit<01:52:58.020> of<01:52:58.199> an<01:52:58.320> intro 01:52:59.450 --> 01:52:59.460 align:start position:0% maybe a few a bit of an intro 01:52:59.460 --> 01:53:02.209 align:start position:0% maybe a few a bit of an intro um<01:52:59.520> right<01:52:59.880> now<01:53:00.060> we<01:53:00.420> have<01:53:00.600> POS<01:53:01.080> as<01:53:01.619> the<01:53:01.860> native 01:53:02.209 --> 01:53:02.219 align:start position:0% um right now we have POS as the native 01:53:02.219 --> 01:53:04.250 align:start position:0% um right now we have POS as the native like<01:53:02.400> consensus<01:53:02.940> algorithm<01:53:03.540> on<01:53:03.840> ethereum 01:53:04.250 --> 01:53:04.260 align:start position:0% like consensus algorithm on ethereum 01:53:04.260 --> 01:53:06.410 align:start position:0% like consensus algorithm on ethereum which<01:53:04.800> is<01:53:04.980> pretty<01:53:05.159> great<01:53:05.520> because<01:53:05.760> verifying 01:53:06.410 --> 01:53:06.420 align:start position:0% which is pretty great because verifying 01:53:06.420 --> 01:53:09.890 align:start position:0% which is pretty great because verifying the<01:53:06.540> consensus<01:53:07.020> is<01:53:07.440> finally<01:53:08.540> doable<01:53:09.540> because 01:53:09.890 --> 01:53:09.900 align:start position:0% the consensus is finally doable because 01:53:09.900 --> 01:53:12.290 align:start position:0% the consensus is finally doable because before<01:53:10.260> like<01:53:10.739> verifying<01:53:11.340> the<01:53:11.820> hashing 01:53:12.290 --> 01:53:12.300 align:start position:0% before like verifying the hashing 01:53:12.300 --> 01:53:14.090 align:start position:0% before like verifying the hashing function<01:53:12.540> eth<01:53:12.960> hash<01:53:13.380> which<01:53:13.560> was<01:53:13.739> used<01:53:13.920> for 01:53:14.090 --> 01:53:14.100 align:start position:0% function eth hash which was used for 01:53:14.100 --> 01:53:16.850 align:start position:0% function eth hash which was used for proof<01:53:14.460> of<01:53:14.520> work<01:53:14.639> was<01:53:14.880> very<01:53:15.119> memory<01:53:15.480> intense<01:53:15.900> so 01:53:16.850 --> 01:53:16.860 align:start position:0% proof of work was very memory intense so 01:53:16.860 --> 01:53:20.149 align:start position:0% proof of work was very memory intense so not<01:53:17.280> possible<01:53:17.639> to<01:53:17.820> do<01:53:17.940> inside<01:53:18.179> the<01:53:18.480> snark 01:53:20.149 --> 01:53:20.159 align:start position:0% not possible to do inside the snark 01:53:20.159 --> 01:53:22.850 align:start position:0% not possible to do inside the snark um<01:53:20.280> on<01:53:20.940> chain<01:53:21.179> directly<01:53:21.719> so<01:53:22.020> it<01:53:22.260> was<01:53:22.440> almost 01:53:22.850 --> 01:53:22.860 align:start position:0% um on chain directly so it was almost 01:53:22.860 --> 01:53:24.770 align:start position:0% um on chain directly so it was almost impossible<01:53:23.400> to<01:53:23.639> do<01:53:23.760> so 01:53:24.770 --> 01:53:24.780 align:start position:0% impossible to do so 01:53:24.780 --> 01:53:27.350 align:start position:0% impossible to do so um<01:53:24.900> so<01:53:25.320> now<01:53:25.560> we<01:53:25.800> also<01:53:26.040> have<01:53:26.219> this<01:53:26.639> Workshop 01:53:27.350 --> 01:53:27.360 align:start position:0% um so now we also have this Workshop 01:53:27.360 --> 01:53:30.370 align:start position:0% um so now we also have this Workshop called<01:53:27.780> lmd<01:53:28.199> ghost<01:53:28.380> which<01:53:28.980> is<01:53:29.360> implementable 01:53:30.370 --> 01:53:30.380 align:start position:0% called lmd ghost which is implementable 01:53:30.380 --> 01:53:33.350 align:start position:0% called lmd ghost which is implementable but<01:53:31.380> doing<01:53:31.980> all<01:53:32.159> of<01:53:32.280> this<01:53:32.400> like<01:53:32.639> directly<01:53:33.060> is 01:53:33.350 --> 01:53:33.360 align:start position:0% but doing all of this like directly is 01:53:33.360 --> 01:53:35.149 align:start position:0% but doing all of this like directly is pretty<01:53:33.600> expensive<01:53:34.139> so<01:53:34.500> we<01:53:34.679> need<01:53:34.800> to<01:53:34.920> ideally 01:53:35.149 --> 01:53:35.159 align:start position:0% pretty expensive so we need to ideally 01:53:35.159 --> 01:53:36.890 align:start position:0% pretty expensive so we need to ideally wrap<01:53:35.520> inside<01:53:35.699> the<01:53:35.880> snark<01:53:36.119> but<01:53:36.420> there<01:53:36.659> is 01:53:36.890 --> 01:53:36.900 align:start position:0% wrap inside the snark but there is 01:53:36.900 --> 01:53:39.470 align:start position:0% wrap inside the snark but there is another<01:53:37.320> downside<01:53:37.860> so<01:53:38.219> a<01:53:38.880> few<01:53:39.060> words<01:53:39.239> about 01:53:39.470 --> 01:53:39.480 align:start position:0% another downside so a few words about 01:53:39.480 --> 01:53:41.590 align:start position:0% another downside so a few words about the<01:53:39.719> trust<01:53:40.080> assumptions 01:53:41.590 --> 01:53:41.600 align:start position:0% the trust assumptions 01:53:41.600 --> 01:53:44.030 align:start position:0% the trust assumptions you<01:53:42.600> well<01:53:42.960> you<01:53:43.199> verify<01:53:43.500> the<01:53:43.619> consensus 01:53:44.030 --> 01:53:44.040 align:start position:0% you well you verify the consensus 01:53:44.040 --> 01:53:46.370 align:start position:0% you well you verify the consensus directly<01:53:44.460> so<01:53:44.880> it's<01:53:45.239> it's<01:53:45.540> fine 01:53:46.370 --> 01:53:46.380 align:start position:0% directly so it's it's fine 01:53:46.380 --> 01:53:48.890 align:start position:0% directly so it's it's fine he<01:53:47.159> do<01:53:48.000> you<01:53:48.179> introduce<01:53:48.420> any<01:53:48.480> trust 01:53:48.890 --> 01:53:48.900 align:start position:0% he do you introduce any trust 01:53:48.900 --> 01:53:51.169 align:start position:0% he do you introduce any trust assumptions<01:53:49.320> not<01:53:50.040> really<01:53:50.280> but<01:53:50.880> the<01:53:51.060> biggest 01:53:51.169 --> 01:53:51.179 align:start position:0% assumptions not really but the biggest 01:53:51.179 --> 01:53:52.970 align:start position:0% assumptions not really but the biggest downside<01:53:51.659> that<01:53:51.900> generating<01:53:52.380> the<01:53:52.619> proof 01:53:52.970 --> 01:53:52.980 align:start position:0% downside that generating the proof 01:53:52.980 --> 01:53:56.810 align:start position:0% downside that generating the proof actually<01:53:53.280> takes<01:53:53.699> some<01:53:54.000> time<01:53:54.440> so<01:53:55.440> to<01:53:56.340> be<01:53:56.460> honest 01:53:56.810 --> 01:53:56.820 align:start position:0% actually takes some time so to be honest 01:53:56.820 --> 01:54:00.169 align:start position:0% actually takes some time so to be honest this<01:53:57.659> approach<01:53:58.020> is<01:53:58.500> feasible<01:53:59.340> but<01:53:59.699> comparing 01:54:00.169 --> 01:54:00.179 align:start position:0% this approach is feasible but comparing 01:54:00.179 --> 01:54:02.990 align:start position:0% this approach is feasible but comparing to<01:54:00.300> messaging<01:54:00.900> like<01:54:01.800> quite<01:54:02.159> often<01:54:02.400> is<01:54:02.580> like 01:54:02.990 --> 01:54:03.000 align:start position:0% to messaging like quite often is like 01:54:03.000 --> 01:54:05.629 align:start position:0% to messaging like quite often is like almost<01:54:03.360> the<01:54:03.659> same<01:54:03.840> and<01:54:04.500> you<01:54:04.739> pay<01:54:04.920> a<01:54:05.400> lot<01:54:05.460> of 01:54:05.629 --> 01:54:05.639 align:start position:0% almost the same and you pay a lot of 01:54:05.639 --> 01:54:07.669 align:start position:0% almost the same and you pay a lot of improving<01:54:06.300> time 01:54:07.669 --> 01:54:07.679 align:start position:0% improving time 01:54:07.679 --> 01:54:10.370 align:start position:0% improving time and<01:54:08.159> requires<01:54:08.639> like<01:54:08.760> having<01:54:09.000> more<01:54:09.659> advanced 01:54:10.370 --> 01:54:10.380 align:start position:0% and requires like having more advanced 01:54:10.380 --> 01:54:13.609 align:start position:0% and requires like having more advanced infrastructure<01:54:11.280> okay<01:54:12.179> last<01:54:12.659> approach<01:54:13.080> that 01:54:13.609 --> 01:54:13.619 align:start position:0% infrastructure okay last approach that 01:54:13.619 --> 01:54:16.550 align:start position:0% infrastructure okay last approach that we<01:54:13.920> actually<01:54:14.159> use<01:54:15.119> is<01:54:15.960> something<01:54:16.199> that<01:54:16.440> we 01:54:16.550 --> 01:54:16.560 align:start position:0% we actually use is something that we 01:54:16.560 --> 01:54:18.470 align:start position:0% we actually use is something that we call<01:54:16.679> like<01:54:16.800> an<01:54:16.980> optimistic<01:54:17.520> relator<01:54:17.880> based<01:54:18.360> on 01:54:18.470 --> 01:54:18.480 align:start position:0% call like an optimistic relator based on 01:54:18.480 --> 01:54:21.290 align:start position:0% call like an optimistic relator based on NPC<01:54:19.199> MPC<01:54:20.159> stands<01:54:20.520> for<01:54:20.580> multi-party 01:54:21.290 --> 01:54:21.300 align:start position:0% NPC MPC stands for multi-party 01:54:21.300 --> 01:54:25.010 align:start position:0% NPC MPC stands for multi-party computation<01:54:21.780> maybe<01:54:22.500> before<01:54:22.860> I<01:54:23.540> explain<01:54:24.540> how 01:54:25.010 --> 01:54:25.020 align:start position:0% computation maybe before I explain how 01:54:25.020 --> 01:54:27.350 align:start position:0% computation maybe before I explain how it<01:54:25.139> works<01:54:25.380> let<01:54:25.560> me<01:54:25.739> explain<01:54:25.860> the<01:54:26.340> the<01:54:26.760> image<01:54:27.119> I 01:54:27.350 --> 01:54:27.360 align:start position:0% it works let me explain the the image I 01:54:27.360 --> 01:54:29.629 align:start position:0% it works let me explain the the image I hope<01:54:27.480> it's<01:54:27.659> self-explanatory<01:54:28.619> so<01:54:29.340> it's<01:54:29.520> an 01:54:29.629 --> 01:54:29.639 align:start position:0% hope it's self-explanatory so it's an 01:54:29.639 --> 01:54:31.609 align:start position:0% hope it's self-explanatory so it's an NPC<01:54:30.000> protocol<01:54:30.360> we<01:54:30.659> have<01:54:30.840> multiple<01:54:31.199> parties 01:54:31.609 --> 01:54:31.619 align:start position:0% NPC protocol we have multiple parties 01:54:31.619 --> 01:54:35.030 align:start position:0% NPC protocol we have multiple parties it's<01:54:32.100> multiple<01:54:32.520> parties<01:54:33.139> attached<01:54:34.139> something 01:54:35.030 --> 01:54:35.040 align:start position:0% it's multiple parties attached something 01:54:35.040 --> 01:54:38.870 align:start position:0% it's multiple parties attached something then<01:54:35.940> we<01:54:36.119> have<01:54:36.360> an<01:54:36.960> observer<01:54:37.560> that<01:54:38.460> can 01:54:38.870 --> 01:54:38.880 align:start position:0% then we have an observer that can 01:54:38.880 --> 01:54:41.149 align:start position:0% then we have an observer that can challenge<01:54:39.239> it<01:54:39.600> and<01:54:39.960> then<01:54:40.080> we<01:54:40.320> have<01:54:40.500> finally 01:54:41.149 --> 01:54:41.159 align:start position:0% challenge it and then we have finally 01:54:41.159 --> 01:54:43.070 align:start position:0% challenge it and then we have finally the<01:54:41.400> commitment<01:54:41.820> given<01:54:42.179> to<01:54:42.360> a<01:54:42.480> specific<01:54:42.780> chain 01:54:43.070 --> 01:54:43.080 align:start position:0% the commitment given to a specific chain 01:54:43.080 --> 01:54:44.930 align:start position:0% the commitment given to a specific chain in<01:54:43.320> this<01:54:43.500> case<01:54:43.619> start<01:54:43.920> net<01:54:44.219> once<01:54:44.820> everything 01:54:44.930 --> 01:54:44.940 align:start position:0% in this case start net once everything 01:54:44.940 --> 01:54:46.129 align:start position:0% in this case start net once everything is<01:54:45.300> fine 01:54:46.129 --> 01:54:46.139 align:start position:0% is fine 01:54:46.139 --> 01:54:49.910 align:start position:0% is fine how<01:54:46.619> does<01:54:46.800> it<01:54:46.920> work<01:54:47.239> so<01:54:48.239> we<01:54:48.600> have<01:54:48.719> a<01:54:48.900> set<01:54:49.080> of 01:54:49.910 --> 01:54:49.920 align:start position:0% how does it work so we have a set of 01:54:49.920 --> 01:54:53.090 align:start position:0% how does it work so we have a set of trusted<01:54:50.760> three<01:54:50.940> layers<01:54:51.560> validators<01:54:52.560> however 01:54:53.090 --> 01:54:53.100 align:start position:0% trusted three layers validators however 01:54:53.100 --> 01:54:54.950 align:start position:0% trusted three layers validators however and<01:54:53.400> they<01:54:53.520> attested<01:54:54.060> a<01:54:54.239> specific<01:54:54.480> commitment 01:54:54.950 --> 01:54:54.960 align:start position:0% and they attested a specific commitment 01:54:54.960 --> 01:54:57.950 align:start position:0% and they attested a specific commitment is<01:54:55.199> valid<01:54:55.500> so<01:54:56.040> how<01:54:56.280> does<01:54:56.460> it<01:54:56.639> work<01:54:56.820> if<01:54:57.540> we<01:54:57.719> want 01:54:57.950 --> 01:54:57.960 align:start position:0% is valid so how does it work if we want 01:54:57.960 --> 01:55:01.310 align:start position:0% is valid so how does it work if we want to<01:54:58.320> get<01:54:59.100> the<01:54:59.400> commitment<01:55:00.179> acreated<01:55:01.020> block 01:55:01.310 --> 01:55:01.320 align:start position:0% to get the commitment acreated block 01:55:01.320 --> 01:55:04.189 align:start position:0% to get the commitment acreated block hash<01:55:01.739> of<01:55:02.340> block<01:55:02.580> number 01:55:04.189 --> 01:55:04.199 align:start position:0% hash of block number 01:55:04.199 --> 01:55:07.669 align:start position:0% hash of block number X<01:55:04.800> on<01:55:05.580> startnet<01:55:06.239> then<01:55:06.780> instead<01:55:07.080> of<01:55:07.199> sending<01:55:07.560> a 01:55:07.669 --> 01:55:07.679 align:start position:0% X on startnet then instead of sending a 01:55:07.679 --> 01:55:10.790 align:start position:0% X on startnet then instead of sending a message<01:55:07.800> that<01:55:08.100> will<01:55:08.219> be<01:55:08.340> delayed<01:55:08.699> with<01:55:09.000> a<01:55:09.800> like 01:55:10.790 --> 01:55:10.800 align:start position:0% message that will be delayed with a like 01:55:10.800 --> 01:55:12.950 align:start position:0% message that will be delayed with a like slightly<01:55:11.219> delayed<01:55:11.639> we<01:55:12.179> can<01:55:12.360> essentially<01:55:12.719> make 01:55:12.950 --> 01:55:12.960 align:start position:0% slightly delayed we can essentially make 01:55:12.960 --> 01:55:15.290 align:start position:0% slightly delayed we can essentially make an<01:55:13.139> offshing<01:55:13.560> call<01:55:13.739> just<01:55:14.340> get<01:55:14.699> the<01:55:14.880> latest<01:55:15.060> one 01:55:15.290 --> 01:55:15.300 align:start position:0% an offshing call just get the latest one 01:55:15.300 --> 01:55:16.490 align:start position:0% an offshing call just get the latest one and<01:55:15.480> essentially<01:55:15.840> relay<01:55:16.199> this<01:55:16.320> message 01:55:16.490 --> 01:55:16.500 align:start position:0% and essentially relay this message 01:55:16.500 --> 01:55:18.890 align:start position:0% and essentially relay this message directly<01:55:17.040> to<01:55:17.639> start<01:55:17.880> net<01:55:18.179> but<01:55:18.360> it<01:55:18.480> comes<01:55:18.719> with 01:55:18.890 --> 01:55:18.900 align:start position:0% directly to start net but it comes with 01:55:18.900 --> 01:55:20.870 align:start position:0% directly to start net but it comes with a<01:55:19.080> few<01:55:19.199> downsides<01:55:19.800> because<01:55:20.340> while<01:55:20.639> we 01:55:20.870 --> 01:55:20.880 align:start position:0% a few downsides because while we 01:55:20.880 --> 01:55:24.350 align:start position:0% a few downsides because while we introduce<01:55:21.239> some<01:55:21.840> trust<01:55:22.679> assumptions<01:55:23.119> uh<01:55:24.119> but 01:55:24.350 --> 01:55:24.360 align:start position:0% introduce some trust assumptions uh but 01:55:24.360 --> 01:55:26.270 align:start position:0% introduce some trust assumptions uh but still<01:55:24.540> it's<01:55:24.719> okay<01:55:24.780> okay<01:55:24.960> how<01:55:25.199> does<01:55:25.380> it<01:55:25.560> work<01:55:25.739> so 01:55:26.270 --> 01:55:26.280 align:start position:0% still it's okay okay how does it work so 01:55:26.280 --> 01:55:27.590 align:start position:0% still it's okay okay how does it work so it<01:55:26.340> works<01:55:26.639> in<01:55:26.760> a<01:55:26.880> way<01:55:26.940> that<01:55:27.119> we<01:55:27.239> have<01:55:27.300> a<01:55:27.480> bunch 01:55:27.590 --> 01:55:27.600 align:start position:0% it works in a way that we have a bunch 01:55:27.600 --> 01:55:29.570 align:start position:0% it works in a way that we have a bunch of<01:55:27.719> off<01:55:27.840> chain<01:55:28.080> actors<01:55:28.500> who<01:55:29.040> essentially<01:55:29.340> make 01:55:29.570 --> 01:55:29.580 align:start position:0% of off chain actors who essentially make 01:55:29.580 --> 01:55:31.970 align:start position:0% of off chain actors who essentially make this<01:55:29.760> calls<01:55:30.119> and<01:55:30.960> it<01:55:31.260> works<01:55:31.560> more<01:55:31.739> or<01:55:31.920> less 01:55:31.970 --> 01:55:31.980 align:start position:0% this calls and it works more or less 01:55:31.980 --> 01:55:34.850 align:start position:0% this calls and it works more or less like<01:55:32.159> a<01:55:32.400> multi-seek<01:55:33.000> but<01:55:33.659> the<01:55:33.900> reason<01:55:34.020> why<01:55:34.679> we 01:55:34.850 --> 01:55:34.860 align:start position:0% like a multi-seek but the reason why we 01:55:34.860 --> 01:55:37.790 align:start position:0% like a multi-seek but the reason why we have<01:55:34.980> NPC<01:55:35.460> is<01:55:35.639> because<01:55:35.880> more<01:55:36.780> validators<01:55:37.560> you 01:55:37.790 --> 01:55:37.800 align:start position:0% have NPC is because more validators you 01:55:37.800 --> 01:55:39.430 align:start position:0% have NPC is because more validators you have<01:55:37.920> than<01:55:38.159> obviously 01:55:39.430 --> 01:55:39.440 align:start position:0% have than obviously 01:55:39.440 --> 01:55:42.050 align:start position:0% have than obviously more<01:55:40.440> Securities<01:55:41.040> but 01:55:42.050 --> 01:55:42.060 align:start position:0% more Securities but 01:55:42.060 --> 01:55:43.970 align:start position:0% more Securities but more<01:55:42.600> validators<01:55:43.139> you<01:55:43.380> have<01:55:43.500> in<01:55:43.619> it<01:55:43.800> like 01:55:43.970 --> 01:55:43.980 align:start position:0% more validators you have in it like 01:55:43.980 --> 01:55:46.370 align:start position:0% more validators you have in it like standard<01:55:44.460> multi-sig<01:55:44.940> approach<01:55:45.300> you<01:55:46.199> have 01:55:46.370 --> 01:55:46.380 align:start position:0% standard multi-sig approach you have 01:55:46.380 --> 01:55:48.290 align:start position:0% standard multi-sig approach you have more<01:55:46.679> signatures<01:55:47.340> so 01:55:48.290 --> 01:55:48.300 align:start position:0% more signatures so 01:55:48.300 --> 01:55:50.510 align:start position:0% more signatures so more<01:55:48.900> in<01:55:49.199> a<01:55:49.380> way<01:55:49.440> decentralized<01:55:50.100> it<01:55:50.159> is<01:55:50.340> then 01:55:50.510 --> 01:55:50.520 align:start position:0% more in a way decentralized it is then 01:55:50.520 --> 01:55:52.790 align:start position:0% more in a way decentralized it is then it's<01:55:51.000> more<01:55:51.659> expensive<01:55:52.080> to<01:55:52.260> verify<01:55:52.619> because 01:55:52.790 --> 01:55:52.800 align:start position:0% it's more expensive to verify because 01:55:52.800 --> 01:55:54.530 align:start position:0% it's more expensive to verify because you<01:55:52.980> need<01:55:53.100> to<01:55:53.219> verify<01:55:53.580> multiple<01:55:53.940> signatures 01:55:54.530 --> 01:55:54.540 align:start position:0% you need to verify multiple signatures 01:55:54.540 --> 01:55:57.169 align:start position:0% you need to verify multiple signatures and<01:55:55.500> you<01:55:55.860> need<01:55:55.980> to<01:55:56.100> like<01:55:56.340> pause<01:55:56.940> the 01:55:57.169 --> 01:55:57.179 align:start position:0% and you need to like pause the 01:55:57.179 --> 01:55:59.330 align:start position:0% and you need to like pause the signatures<01:55:57.659> it's<01:55:57.900> a<01:55:58.080> lot<01:55:58.199> of<01:55:58.320> cool<01:55:58.440> data<01:55:58.920> such 01:55:59.330 --> 01:55:59.340 align:start position:0% signatures it's a lot of cool data such 01:55:59.340 --> 01:56:01.910 align:start position:0% signatures it's a lot of cool data such approach<01:55:59.699> is<01:55:59.880> not<01:56:00.060> feasible<01:56:00.480> on<01:56:01.139> chains 01:56:01.910 --> 01:56:01.920 align:start position:0% approach is not feasible on chains 01:56:01.920 --> 01:56:04.330 align:start position:0% approach is not feasible on chains Oracle<01:56:02.280> data<01:56:02.520> is<01:56:02.580> expensive<01:56:03.000> so<01:56:03.300> at<01:56:03.900> one 01:56:04.330 --> 01:56:04.340 align:start position:0% Oracle data is expensive so at one 01:56:04.340 --> 01:56:07.850 align:start position:0% Oracle data is expensive so at one optimistic<01:56:05.340> rollups<01:56:05.880> and<01:56:06.600> yeah 01:56:07.850 --> 01:56:07.860 align:start position:0% optimistic rollups and yeah 01:56:07.860 --> 01:56:10.729 align:start position:0% optimistic rollups and yeah okay<01:56:08.340> so<01:56:08.639> how<01:56:08.820> does<01:56:09.000> it<01:56:09.179> work<01:56:09.300> uh<01:56:09.900> what<01:56:10.260> is<01:56:10.440> uh 01:56:10.729 --> 01:56:10.739 align:start position:0% okay so how does it work uh what is uh 01:56:10.739 --> 01:56:13.550 align:start position:0% okay so how does it work uh what is uh actually<01:56:10.980> NPC<01:56:11.580> part<01:56:11.760> doing<01:56:12.060> the<01:56:12.300> MPC<01:56:12.719> part<01:56:12.900> is 01:56:13.550 --> 01:56:13.560 align:start position:0% actually NPC part doing the MPC part is 01:56:13.560 --> 01:56:16.010 align:start position:0% actually NPC part doing the MPC part is very<01:56:13.860> simple<01:56:14.040> it's<01:56:14.520> essentially<01:56:15.020> signing 01:56:16.010 --> 01:56:16.020 align:start position:0% very simple it's essentially signing 01:56:16.020 --> 01:56:19.370 align:start position:0% very simple it's essentially signing over<01:56:16.460> like<01:56:17.460> a<01:56:17.639> specific<01:56:18.000> curve<01:56:18.420> some<01:56:18.960> specific 01:56:19.370 --> 01:56:19.380 align:start position:0% over like a specific curve some specific 01:56:19.380 --> 01:56:20.990 align:start position:0% over like a specific curve some specific payload<01:56:19.920> and<01:56:20.040> the<01:56:20.159> payload<01:56:20.580> is<01:56:20.699> the 01:56:20.990 --> 01:56:21.000 align:start position:0% payload and the payload is the 01:56:21.000 --> 01:56:23.629 align:start position:0% payload and the payload is the commitment<01:56:21.360> itself<01:56:21.719> and<01:56:22.619> that's<01:56:22.800> it<01:56:22.980> okay<01:56:23.219> so 01:56:23.629 --> 01:56:23.639 align:start position:0% commitment itself and that's it okay so 01:56:23.639 --> 01:56:26.510 align:start position:0% commitment itself and that's it okay so this<01:56:23.820> is<01:56:23.940> how<01:56:24.300> we<01:56:25.020> actually<01:56:25.199> attest<01:56:25.860> but<01:56:26.280> now 01:56:26.510 --> 01:56:26.520 align:start position:0% this is how we actually attest but now 01:56:26.520 --> 01:56:28.550 align:start position:0% this is how we actually attest but now how<01:56:26.940> why<01:56:27.360> this<01:56:27.719> approach<01:56:28.260> is<01:56:28.380> called 01:56:28.550 --> 01:56:28.560 align:start position:0% how why this approach is called 01:56:28.560 --> 01:56:31.010 align:start position:0% how why this approach is called optimistic<01:56:29.159> and<01:56:29.400> why<01:56:29.639> it's<01:56:29.820> still<01:56:30.060> secure 01:56:31.010 --> 01:56:31.020 align:start position:0% optimistic and why it's still secure 01:56:31.020 --> 01:56:34.310 align:start position:0% optimistic and why it's still secure so<01:56:31.920> first<01:56:32.280> of<01:56:32.460> all<01:56:32.639> we<01:56:33.540> just<01:56:33.719> posted<01:56:34.080> some 01:56:34.310 --> 01:56:34.320 align:start position:0% so first of all we just posted some 01:56:34.320 --> 01:56:36.530 align:start position:0% so first of all we just posted some something<01:56:34.619> on<01:56:34.980> the<01:56:35.100> actual<01:56:35.340> L2<01:56:35.760> and<01:56:36.119> as<01:56:36.360> you 01:56:36.530 --> 01:56:36.540 align:start position:0% something on the actual L2 and as you 01:56:36.540 --> 01:56:38.810 align:start position:0% something on the actual L2 and as you may<01:56:36.659> know<01:56:36.840> we<01:56:37.260> can<01:56:37.440> send<01:56:37.560> messages<01:56:37.860> from<01:56:38.219> L1<01:56:38.580> to 01:56:38.810 --> 01:56:38.820 align:start position:0% may know we can send messages from L1 to 01:56:38.820 --> 01:56:42.350 align:start position:0% may know we can send messages from L1 to L2<01:56:39.600> and<01:56:39.960> such<01:56:40.080> a<01:56:40.320> message<01:56:40.500> can<01:56:40.920> contain<01:56:41.400> like 01:56:42.350 --> 01:56:42.360 align:start position:0% L2 and such a message can contain like 01:56:42.360 --> 01:56:43.910 align:start position:0% L2 and such a message can contain like the<01:56:42.600> proper<01:56:42.960> commitment<01:56:43.320> so<01:56:43.560> essentially 01:56:43.910 --> 01:56:43.920 align:start position:0% the proper commitment so essentially 01:56:43.920 --> 01:56:47.570 align:start position:0% the proper commitment so essentially even<01:56:44.159> if<01:56:44.460> the<01:56:44.639> validator<01:56:45.360> set<01:56:45.719> will<01:56:46.260> lie<01:56:46.619> L1 01:56:47.570 --> 01:56:47.580 align:start position:0% even if the validator set will lie L1 01:56:47.580 --> 01:56:49.430 align:start position:0% even if the validator set will lie L1 will<01:56:47.880> never<01:56:48.060> lie<01:56:48.480> so<01:56:48.659> you<01:56:48.840> can<01:56:48.960> just<01:56:49.139> challenge 01:56:49.430 --> 01:56:49.440 align:start position:0% will never lie so you can just challenge 01:56:49.440 --> 01:56:52.370 align:start position:0% will never lie so you can just challenge such<01:56:49.800> a<01:56:49.980> message<01:56:50.100> and<01:56:50.699> now<01:56:50.940> to<01:56:51.719> participate<01:56:52.199> in 01:56:52.370 --> 01:56:52.380 align:start position:0% such a message and now to participate in 01:56:52.380 --> 01:56:54.410 align:start position:0% such a message and now to participate in verifying<01:56:53.100> this<01:56:53.400> validators<01:56:54.000> it's<01:56:54.239> super 01:56:54.410 --> 01:56:54.420 align:start position:0% verifying this validators it's super 01:56:54.420 --> 01:56:56.810 align:start position:0% verifying this validators it's super easy<01:56:54.600> because<01:56:54.900> literally<01:56:55.320> two<01:56:55.800> RP<01:56:56.340> sequels 01:56:56.810 --> 01:56:56.820 align:start position:0% easy because literally two RP sequels 01:56:56.820 --> 01:56:58.970 align:start position:0% easy because literally two RP sequels one<01:56:57.480> call<01:56:57.719> is<01:56:58.020> gonna<01:56:58.260> check<01:56:58.500> the<01:56:58.739> actual 01:56:58.970 --> 01:56:58.980 align:start position:0% one call is gonna check the actual 01:56:58.980 --> 01:57:01.070 align:start position:0% one call is gonna check the actual commitment<01:56:59.400> on<01:56:59.699> the<01:56:59.820> actual<01:57:00.060> chain<01:57:00.300> and<01:57:00.900> the 01:57:01.070 --> 01:57:01.080 align:start position:0% commitment on the actual chain and the 01:57:01.080 --> 01:57:03.709 align:start position:0% commitment on the actual chain and the other<01:57:01.199> one<01:57:01.440> checks<01:57:01.980> like<01:57:02.400> what<01:57:03.179> is<01:57:03.360> the 01:57:03.709 --> 01:57:03.719 align:start position:0% other one checks like what is the 01:57:03.719 --> 01:57:06.890 align:start position:0% other one checks like what is the claimed<01:57:04.260> Commitment<01:57:04.679> if<01:57:05.340> you<01:57:05.460> disagree 01:57:06.890 --> 01:57:06.900 align:start position:0% claimed Commitment if you disagree 01:57:06.900 --> 01:57:09.530 align:start position:0% claimed Commitment if you disagree you<01:57:07.440> just<01:57:07.679> send<01:57:07.920> a<01:57:08.100> message<01:57:08.280> it<01:57:08.699> costs<01:57:09.060> roughly 01:57:09.530 --> 01:57:09.540 align:start position:0% you just send a message it costs roughly 01:57:09.540 --> 01:57:12.350 align:start position:0% you just send a message it costs roughly 60<01:57:10.260> K<01:57:10.679> of<01:57:10.920> gas 01:57:12.350 --> 01:57:12.360 align:start position:0% 60 K of gas 01:57:12.360 --> 01:57:15.350 align:start position:0% 60 K of gas and<01:57:12.840> that's<01:57:12.960> it<01:57:13.199> everyone<01:57:13.739> can<01:57:14.040> do<01:57:14.219> that 01:57:15.350 --> 01:57:15.360 align:start position:0% and that's it everyone can do that 01:57:15.360 --> 01:57:16.010 align:start position:0% and that's it everyone can do that um 01:57:16.010 --> 01:57:16.020 align:start position:0% um 01:57:16.020 --> 01:57:18.770 align:start position:0% um and<01:57:16.739> again<01:57:16.920> the<01:57:17.580> fraud<01:57:17.940> proving<01:57:18.300> window<01:57:18.420> is 01:57:18.770 --> 01:57:18.780 align:start position:0% and again the fraud proving window is 01:57:18.780 --> 01:57:21.410 align:start position:0% and again the fraud proving window is pretty<01:57:19.020> short<01:57:19.199> because<01:57:20.119> it's<01:57:21.119> essentially 01:57:21.410 --> 01:57:21.420 align:start position:0% pretty short because it's essentially 01:57:21.420 --> 01:57:23.209 align:start position:0% pretty short because it's essentially how<01:57:21.659> long<01:57:21.780> it<01:57:21.960> will<01:57:22.139> take<01:57:22.260> to<01:57:22.500> generate<01:57:23.099> like 01:57:23.209 --> 01:57:23.219 align:start position:0% how long it will take to generate like 01:57:23.219 --> 01:57:25.129 align:start position:0% how long it will take to generate like the<01:57:23.400> proof<01:57:23.639> of<01:57:23.699> consensus<01:57:24.179> if<01:57:24.599> it's<01:57:24.719> possible 01:57:25.129 --> 01:57:25.139 align:start position:0% the proof of consensus if it's possible 01:57:25.139 --> 01:57:27.770 align:start position:0% the proof of consensus if it's possible or<01:57:26.099> how<01:57:26.520> long<01:57:26.639> does<01:57:26.820> it<01:57:27.000> take<01:57:27.119> to<01:57:27.239> deliver<01:57:27.420> the 01:57:27.770 --> 01:57:27.780 align:start position:0% or how long does it take to deliver the 01:57:27.780 --> 01:57:29.990 align:start position:0% or how long does it take to deliver the message<01:57:27.960> and<01:57:28.920> what<01:57:29.040> is<01:57:29.280> pretty<01:57:29.460> cool<01:57:29.639> in<01:57:29.820> this 01:57:29.990 --> 01:57:30.000 align:start position:0% message and what is pretty cool in this 01:57:30.000 --> 01:57:32.450 align:start position:0% message and what is pretty cool in this approach<01:57:30.300> it's<01:57:30.599> not<01:57:30.840> gas<01:57:31.080> intensive<01:57:31.679> we 01:57:32.450 --> 01:57:32.460 align:start position:0% approach it's not gas intensive we 01:57:32.460 --> 01:57:35.689 align:start position:0% approach it's not gas intensive we verify<01:57:32.880> just<01:57:33.060> one<01:57:33.239> signature<01:57:33.980> so<01:57:34.980> that's 01:57:35.689 --> 01:57:35.699 align:start position:0% verify just one signature so that's 01:57:35.699 --> 01:57:37.129 align:start position:0% verify just one signature so that's about<01:57:35.940> this<01:57:36.179> approach 01:57:37.129 --> 01:57:37.139 align:start position:0% about this approach 01:57:37.139 --> 01:57:39.530 align:start position:0% about this approach let's<01:57:37.920> make<01:57:38.159> a<01:57:38.280> recap<01:57:38.580> and<01:57:38.940> let's<01:57:39.119> identify 01:57:39.530 --> 01:57:39.540 align:start position:0% let's make a recap and let's identify 01:57:39.540 --> 01:57:41.089 align:start position:0% let's make a recap and let's identify the<01:57:39.719> trade-offs 01:57:41.089 --> 01:57:41.099 align:start position:0% the trade-offs 01:57:41.099 --> 01:57:43.669 align:start position:0% the trade-offs so<01:57:41.639> we<01:57:42.000> have<01:57:42.119> three<01:57:42.420> approaches<01:57:42.960> the<01:57:43.560> first 01:57:43.669 --> 01:57:43.679 align:start position:0% so we have three approaches the first 01:57:43.679 --> 01:57:45.770 align:start position:0% so we have three approaches the first one<01:57:43.860> is<01:57:44.040> messaging<01:57:44.580> the<01:57:45.300> second<01:57:45.480> one<01:57:45.659> is 01:57:45.770 --> 01:57:45.780 align:start position:0% one is messaging the second one is 01:57:45.780 --> 01:57:47.810 align:start position:0% one is messaging the second one is validating<01:57:46.199> the<01:57:46.380> consensus<01:57:46.860> and<01:57:47.580> the<01:57:47.699> third 01:57:47.810 --> 01:57:47.820 align:start position:0% validating the consensus and the third 01:57:47.820 --> 01:57:50.990 align:start position:0% validating the consensus and the third one<01:57:48.060> is<01:57:48.239> having<01:57:48.900> this<01:57:49.199> optimistic<01:57:49.679> layer<01:57:50.099> so<01:57:50.760> I 01:57:50.990 --> 01:57:51.000 align:start position:0% one is having this optimistic layer so I 01:57:51.000 --> 01:57:55.129 align:start position:0% one is having this optimistic layer so I categorize<01:57:51.480> it<01:57:51.719> in<01:57:52.219> four<01:57:53.480> categories<01:57:54.480> the 01:57:55.129 --> 01:57:55.139 align:start position:0% categorize it in four categories the 01:57:55.139 --> 01:57:58.430 align:start position:0% categorize it in four categories the first<01:57:55.320> one<01:57:55.500> is<01:57:55.860> latency<01:57:56.540> the<01:57:57.540> second<01:57:57.719> one<01:57:58.080> is 01:57:58.430 --> 01:57:58.440 align:start position:0% first one is latency the second one is 01:57:58.440 --> 01:58:01.970 align:start position:0% first one is latency the second one is the<01:57:58.980> gas<01:57:59.159> cost<01:57:59.460> the<01:58:00.420> third<01:58:00.599> one<01:58:00.780> is<01:58:01.020> trust<01:58:01.679> and 01:58:01.970 --> 01:58:01.980 align:start position:0% the gas cost the third one is trust and 01:58:01.980 --> 01:58:03.770 align:start position:0% the gas cost the third one is trust and the<01:58:02.099> last<01:58:02.219> one<01:58:02.400> is<01:58:02.580> what<01:58:03.060> is<01:58:03.179> the<01:58:03.300> off-ching 01:58:03.770 --> 01:58:03.780 align:start position:0% the last one is what is the off-ching 01:58:03.780 --> 01:58:06.229 align:start position:0% the last one is what is the off-ching computation<01:58:04.260> overhead<01:58:04.860> why<01:58:05.520> do<01:58:05.699> I<01:58:05.820> even<01:58:05.940> list 01:58:06.229 --> 01:58:06.239 align:start position:0% computation overhead why do I even list 01:58:06.239 --> 01:58:08.450 align:start position:0% computation overhead why do I even list it<01:58:06.420> because<01:58:06.599> if<01:58:06.960> we<01:58:07.139> do<01:58:07.320> some<01:58:07.560> sort<01:58:07.800> of<01:58:07.920> proving 01:58:08.450 --> 01:58:08.460 align:start position:0% it because if we do some sort of proving 01:58:08.460 --> 01:58:10.010 align:start position:0% it because if we do some sort of proving then<01:58:08.760> obviously<01:58:09.179> it<01:58:09.300> takes<01:58:09.420> time<01:58:09.659> because<01:58:09.840> we 01:58:10.010 --> 01:58:10.020 align:start position:0% then obviously it takes time because we 01:58:10.020 --> 01:58:11.570 align:start position:0% then obviously it takes time because we need<01:58:10.139> to<01:58:10.260> generate<01:58:10.560> the<01:58:10.739> proof 01:58:11.570 --> 01:58:11.580 align:start position:0% need to generate the proof 01:58:11.580 --> 01:58:15.350 align:start position:0% need to generate the proof so<01:58:12.179> messaging<01:58:12.780> in<01:58:13.320> terms<01:58:13.560> of<01:58:13.619> latency<01:58:14.099> we<01:58:15.060> are 01:58:15.350 --> 01:58:15.360 align:start position:0% so messaging in terms of latency we are 01:58:15.360 --> 01:58:17.629 align:start position:0% so messaging in terms of latency we are quite<01:58:15.599> sad<01:58:15.900> because<01:58:16.440> well<01:58:16.860> the<01:58:17.099> message<01:58:17.280> needs 01:58:17.629 --> 01:58:17.639 align:start position:0% quite sad because well the message needs 01:58:17.639 --> 01:58:19.850 align:start position:0% quite sad because well the message needs to<01:58:17.699> get<01:58:17.820> delivered<01:58:18.300> so<01:58:18.840> once<01:58:19.560> the<01:58:19.679> message 01:58:19.850 --> 01:58:19.860 align:start position:0% to get delivered so once the message 01:58:19.860 --> 01:58:23.510 align:start position:0% to get delivered so once the message gets<01:58:20.280> delivered<01:58:20.639> to<01:58:20.940> some<01:58:21.540> specific<01:58:22.020> L2<01:58:22.619> L1 01:58:23.510 --> 01:58:23.520 align:start position:0% gets delivered to some specific L2 L1 01:58:23.520 --> 01:58:25.910 align:start position:0% gets delivered to some specific L2 L1 will<01:58:24.119> be<01:58:24.780> able<01:58:24.960> to<01:58:25.080> generate<01:58:25.380> already<01:58:25.619> new 01:58:25.910 --> 01:58:25.920 align:start position:0% will be able to generate already new 01:58:25.920 --> 01:58:27.589 align:start position:0% will be able to generate already new block<01:58:26.099> so<01:58:26.340> we<01:58:26.460> don't<01:58:26.580> have<01:58:26.760> like<01:58:27.000> access<01:58:27.239> to 01:58:27.589 --> 01:58:27.599 align:start position:0% block so we don't have like access to 01:58:27.599 --> 01:58:29.450 align:start position:0% block so we don't have like access to the<01:58:27.840> newest<01:58:28.320> values 01:58:29.450 --> 01:58:29.460 align:start position:0% the newest values 01:58:29.460 --> 01:58:32.149 align:start position:0% the newest values in<01:58:29.760> terms<01:58:29.880> of<01:58:30.000> gas<01:58:30.179> cost<01:58:30.480> it's<01:58:31.440> not<01:58:31.679> bad<01:58:31.860> but 01:58:32.149 --> 01:58:32.159 align:start position:0% in terms of gas cost it's not bad but 01:58:32.159 --> 01:58:33.709 align:start position:0% in terms of gas cost it's not bad but it's<01:58:32.340> not<01:58:32.520> perfect<01:58:32.699> because<01:58:33.119> we<01:58:33.480> need<01:58:33.599> to 01:58:33.709 --> 01:58:33.719 align:start position:0% it's not perfect because we need to 01:58:33.719 --> 01:58:35.270 align:start position:0% it's not perfect because we need to interact<01:58:34.080> with<01:58:34.320> two<01:58:34.500> chains<01:58:34.860> at<01:58:34.980> the<01:58:35.159> same 01:58:35.270 --> 01:58:35.280 align:start position:0% interact with two chains at the same 01:58:35.280 --> 01:58:36.830 align:start position:0% interact with two chains at the same time<01:58:35.400> so<01:58:35.699> first<01:58:35.880> we<01:58:36.060> need<01:58:36.239> to<01:58:36.360> send<01:58:36.540> a<01:58:36.719> message 01:58:36.830 --> 01:58:36.840 align:start position:0% time so first we need to send a message 01:58:36.840 --> 01:58:38.629 align:start position:0% time so first we need to send a message and<01:58:37.139> consume<01:58:37.739> it 01:58:38.629 --> 01:58:38.639 align:start position:0% and consume it 01:58:38.639 --> 01:58:40.669 align:start position:0% and consume it in<01:58:39.119> terms<01:58:39.300> of<01:58:39.420> trust<01:58:39.719> we<01:58:39.960> are<01:58:40.199> pretty<01:58:40.380> happy 01:58:40.669 --> 01:58:40.679 align:start position:0% in terms of trust we are pretty happy 01:58:40.679 --> 01:58:43.729 align:start position:0% in terms of trust we are pretty happy because<01:58:41.520> we<01:58:42.119> trust<01:58:42.719> the<01:58:42.960> roll<01:58:43.080> up<01:58:43.260> itself<01:58:43.560> and 01:58:43.729 --> 01:58:43.739 align:start position:0% because we trust the roll up itself and 01:58:43.739 --> 01:58:45.649 align:start position:0% because we trust the roll up itself and it's<01:58:43.860> a<01:58:44.040> fair<01:58:44.159> assumption 01:58:45.649 --> 01:58:45.659 align:start position:0% it's a fair assumption 01:58:45.659 --> 01:58:47.570 align:start position:0% it's a fair assumption option<01:58:46.260> computation<01:58:46.739> overhead<01:58:47.099> we're<01:58:47.340> very 01:58:47.570 --> 01:58:47.580 align:start position:0% option computation overhead we're very 01:58:47.580 --> 01:58:49.970 align:start position:0% option computation overhead we're very happy<01:58:47.820> because<01:58:48.119> there<01:58:48.420> is<01:58:48.599> no<01:58:48.960> computation<01:58:49.560> to 01:58:49.970 --> 01:58:49.980 align:start position:0% happy because there is no computation to 01:58:49.980 --> 01:58:53.209 align:start position:0% happy because there is no computation to do<01:58:50.280> off-chain<01:58:50.960> verifying<01:58:51.960> the<01:58:52.080> consensus<01:58:52.560> so 01:58:53.209 --> 01:58:53.219 align:start position:0% do off-chain verifying the consensus so 01:58:53.219 --> 01:58:54.830 align:start position:0% do off-chain verifying the consensus so in<01:58:53.340> terms<01:58:53.520> of<01:58:53.580> latency<01:58:53.940> we<01:58:54.239> are<01:58:54.420> side<01:58:54.599> because 01:58:54.830 --> 01:58:54.840 align:start position:0% in terms of latency we are side because 01:58:54.840 --> 01:58:56.990 align:start position:0% in terms of latency we are side because we<01:58:55.020> need<01:58:55.139> to<01:58:55.260> generate<01:58:55.560> the<01:58:55.739> proof 01:58:56.990 --> 01:58:57.000 align:start position:0% we need to generate the proof 01:58:57.000 --> 01:58:58.430 align:start position:0% we need to generate the proof that<01:58:57.239> we've<01:58:57.420> done<01:58:57.599> it<01:58:57.719> it<01:58:57.840> takes<01:58:58.020> a<01:58:58.199> bit<01:58:58.320> of 01:58:58.430 --> 01:58:58.440 align:start position:0% that we've done it it takes a bit of 01:58:58.440 --> 01:59:01.970 align:start position:0% that we've done it it takes a bit of time<01:58:58.679> in<01:58:59.219> terms<01:58:59.400> of<01:58:59.460> gas<01:58:59.699> cost<01:58:59.940> we<01:59:00.780> are<01:59:01.020> I<01:59:01.860> would 01:59:01.970 --> 01:59:01.980 align:start position:0% time in terms of gas cost we are I would 01:59:01.980 --> 01:59:04.010 align:start position:0% time in terms of gas cost we are I would say<01:59:02.159> sad<01:59:02.520> because<01:59:02.880> we<01:59:03.239> need<01:59:03.360> to<01:59:03.480> verify<01:59:03.840> the 01:59:04.010 --> 01:59:04.020 align:start position:0% say sad because we need to verify the 01:59:04.020 --> 01:59:05.930 align:start position:0% say sad because we need to verify the actual<01:59:04.260> ZK<01:59:04.619> proof<01:59:04.980> which<01:59:05.099> is<01:59:05.280> way<01:59:05.760> more 01:59:05.930 --> 01:59:05.940 align:start position:0% actual ZK proof which is way more 01:59:05.940 --> 01:59:08.990 align:start position:0% actual ZK proof which is way more expensive<01:59:06.480> than<01:59:06.840> just 01:59:08.990 --> 01:59:09.000 align:start position:0% expensive than just 01:59:09.000 --> 01:59:11.089 align:start position:0% expensive than just consuming<01:59:09.659> a<01:59:09.840> message<01:59:10.020> or<01:59:10.440> verifying<01:59:10.980> a 01:59:11.089 --> 01:59:11.099 align:start position:0% consuming a message or verifying a 01:59:11.099 --> 01:59:13.430 align:start position:0% consuming a message or verifying a signature<01:59:11.580> in<01:59:12.300> terms<01:59:12.420> of<01:59:12.480> trust<01:59:12.840> we<01:59:13.080> are<01:59:13.260> happy 01:59:13.430 --> 01:59:13.440 align:start position:0% signature in terms of trust we are happy 01:59:13.440 --> 01:59:15.890 align:start position:0% signature in terms of trust we are happy because<01:59:13.739> we<01:59:13.980> verify<01:59:14.340> the<01:59:14.460> consensus<01:59:14.880> itself 01:59:15.890 --> 01:59:15.900 align:start position:0% because we verify the consensus itself 01:59:15.900 --> 01:59:18.290 align:start position:0% because we verify the consensus itself and<01:59:16.860> computation<01:59:17.400> overhead<01:59:17.880> it's 01:59:18.290 --> 01:59:18.300 align:start position:0% and computation overhead it's 01:59:18.300 --> 01:59:19.609 align:start position:0% and computation overhead it's significant<01:59:18.719> right<01:59:18.960> because<01:59:19.199> we<01:59:19.380> need<01:59:19.500> to 01:59:19.609 --> 01:59:19.619 align:start position:0% significant right because we need to 01:59:19.619 --> 01:59:21.050 align:start position:0% significant right because we need to generate<01:59:19.860> the<01:59:19.980> proof 01:59:21.050 --> 01:59:21.060 align:start position:0% generate the proof 01:59:21.060 --> 01:59:22.550 align:start position:0% generate the proof Final<01:59:21.480> Approach 01:59:22.550 --> 01:59:22.560 align:start position:0% Final Approach 01:59:22.560 --> 01:59:25.550 align:start position:0% Final Approach this<01:59:23.099> optimistic<01:59:23.699> layer<01:59:24.239> so<01:59:25.080> in<01:59:25.260> terms<01:59:25.500> of 01:59:25.550 --> 01:59:25.560 align:start position:0% this optimistic layer so in terms of 01:59:25.560 --> 01:59:27.410 align:start position:0% this optimistic layer so in terms of latency<01:59:25.920> we're<01:59:26.159> happy<01:59:26.340> because<01:59:26.580> we<01:59:26.940> simply 01:59:27.410 --> 01:59:27.420 align:start position:0% latency we're happy because we simply 01:59:27.420 --> 01:59:29.149 align:start position:0% latency we're happy because we simply make<01:59:27.540> a<01:59:27.719> claim<01:59:27.960> and<01:59:28.080> we<01:59:28.260> post<01:59:28.619> it<01:59:28.860> on<01:59:28.980> the<01:59:29.099> other 01:59:29.149 --> 01:59:29.159 align:start position:0% make a claim and we post it on the other 01:59:29.159 --> 01:59:31.669 align:start position:0% make a claim and we post it on the other chain<01:59:29.520> that's<01:59:29.880> it<01:59:30.119> gas<01:59:30.659> cost<01:59:30.960> we're<01:59:31.500> very 01:59:31.669 --> 01:59:31.679 align:start position:0% chain that's it gas cost we're very 01:59:31.679 --> 01:59:33.169 align:start position:0% chain that's it gas cost we're very happy<01:59:31.860> because<01:59:32.159> the 01:59:33.169 --> 01:59:33.179 align:start position:0% happy because the 01:59:33.179 --> 01:59:35.629 align:start position:0% happy because the well<01:59:33.599> we<01:59:33.900> just<01:59:34.020> verify<01:59:34.320> a<01:59:34.440> signature 01:59:35.629 --> 01:59:35.639 align:start position:0% well we just verify a signature 01:59:35.639 --> 01:59:38.030 align:start position:0% well we just verify a signature in<01:59:35.940> terms<01:59:36.179> of<01:59:36.300> trust<01:59:36.780> well<01:59:37.139> we<01:59:37.440> are<01:59:37.679> not<01:59:37.800> that 01:59:38.030 --> 01:59:38.040 align:start position:0% in terms of trust well we are not that 01:59:38.040 --> 01:59:39.950 align:start position:0% in terms of trust well we are not that happy<01:59:38.280> but<01:59:38.580> also<01:59:38.820> not<01:59:39.000> that<01:59:39.179> sad<01:59:39.420> at<01:59:39.659> the<01:59:39.780> same 01:59:39.950 --> 01:59:39.960 align:start position:0% happy but also not that sad at the same 01:59:39.960 --> 01:59:42.229 align:start position:0% happy but also not that sad at the same time<01:59:40.139> because<01:59:40.679> it<01:59:41.099> still<01:59:41.520> can<01:59:41.699> be<01:59:41.880> challenged 01:59:42.229 --> 01:59:42.239 align:start position:0% time because it still can be challenged 01:59:42.239 --> 01:59:44.450 align:start position:0% time because it still can be challenged in<01:59:42.420> an<01:59:42.599> optimistic<01:59:43.080> manner<01:59:43.440> using<01:59:44.099> a<01:59:44.219> fraud 01:59:44.450 --> 01:59:44.460 align:start position:0% in an optimistic manner using a fraud 01:59:44.460 --> 01:59:45.790 align:start position:0% in an optimistic manner using a fraud proof 01:59:45.790 --> 01:59:45.800 align:start position:0% proof 01:59:45.800 --> 01:59:48.350 align:start position:0% proof computation<01:59:46.800> option<01:59:47.460> computation<01:59:47.940> overhead 01:59:48.350 --> 01:59:48.360 align:start position:0% computation option computation overhead 01:59:48.360 --> 01:59:50.330 align:start position:0% computation option computation overhead are<01:59:48.900> pretty<01:59:49.080> happy<01:59:49.320> because<01:59:49.560> we<01:59:49.860> participate 01:59:50.330 --> 01:59:50.340 align:start position:0% are pretty happy because we participate 01:59:50.340 --> 01:59:52.910 align:start position:0% are pretty happy because we participate like<01:59:50.520> an<01:59:50.699> MPC<01:59:51.179> protocol<01:59:51.960> so<01:59:52.320> essentially<01:59:52.679> the 01:59:52.910 --> 01:59:52.920 align:start position:0% like an MPC protocol so essentially the 01:59:52.920 --> 01:59:54.830 align:start position:0% like an MPC protocol so essentially the overhead<01:59:53.340> comes<01:59:53.820> mostly<01:59:54.060> from<01:59:54.300> communication 01:59:54.830 --> 01:59:54.840 align:start position:0% overhead comes mostly from communication 01:59:54.840 --> 01:59:57.770 align:start position:0% overhead comes mostly from communication not<01:59:55.739> computation<01:59:56.340> itself 01:59:57.770 --> 01:59:57.780 align:start position:0% not computation itself 01:59:57.780 --> 02:00:00.830 align:start position:0% not computation itself cool<01:59:58.440> so<01:59:59.099> this<01:59:59.460> is<01:59:59.580> part<01:59:59.820> number<02:00:00.000> one<02:00:00.300> these 02:00:00.830 --> 02:00:00.840 align:start position:0% cool so this is part number one these 02:00:00.840 --> 02:00:03.229 align:start position:0% cool so this is part number one these are<02:00:00.900> the<02:00:01.139> three<02:00:01.560> approaches<02:00:02.219> obviously<02:00:02.760> I'm 02:00:03.229 --> 02:00:03.239 align:start position:0% are the three approaches obviously I'm 02:00:03.239 --> 02:00:04.729 align:start position:0% are the three approaches obviously I'm not<02:00:03.420> gonna<02:00:03.540> say<02:00:03.780> which<02:00:04.080> one<02:00:04.260> is<02:00:04.440> the<02:00:04.619> best 02:00:04.729 --> 02:00:04.739 align:start position:0% not gonna say which one is the best 02:00:04.739 --> 02:00:06.709 align:start position:0% not gonna say which one is the best because<02:00:05.280> all<02:00:05.940> of<02:00:06.060> them<02:00:06.179> come<02:00:06.360> with<02:00:06.540> some 02:00:06.709 --> 02:00:06.719 align:start position:0% because all of them come with some 02:00:06.719 --> 02:00:08.270 align:start position:0% because all of them come with some trade-offs 02:00:08.270 --> 02:00:08.280 align:start position:0% trade-offs 02:00:08.280 --> 02:00:11.149 align:start position:0% trade-offs um<02:00:08.400> okay<02:00:08.900> accessing<02:00:09.900> the<02:00:10.080> headers<02:00:10.440> I<02:00:11.040> hope 02:00:11.149 --> 02:00:11.159 align:start position:0% um okay accessing the headers I hope 02:00:11.159 --> 02:00:12.709 align:start position:0% um okay accessing the headers I hope it's<02:00:11.280> self-explanatory<02:00:12.119> because<02:00:12.420> we 02:00:12.709 --> 02:00:12.719 align:start position:0% it's self-explanatory because we 02:00:12.719 --> 02:00:15.109 align:start position:0% it's self-explanatory because we literally<02:00:13.500> unroll<02:00:14.040> something<02:00:14.699> from<02:00:15.000> The 02:00:15.109 --> 02:00:15.119 align:start position:0% literally unroll something from The 02:00:15.119 --> 02:00:17.030 align:start position:0% literally unroll something from The Trusted<02:00:15.540> input 02:00:17.030 --> 02:00:17.040 align:start position:0% Trusted input 02:00:17.040 --> 02:00:19.010 align:start position:0% Trusted input and<02:00:17.400> The<02:00:17.520> Trusted<02:00:17.880> input<02:00:18.179> is<02:00:18.360> again<02:00:18.480> a<02:00:18.840> block 02:00:19.010 --> 02:00:19.020 align:start position:0% and The Trusted input is again a block 02:00:19.020 --> 02:00:22.850 align:start position:0% and The Trusted input is again a block hush<02:00:19.440> for<02:00:19.800> a<02:00:20.040> specific<02:00:20.340> block<02:00:20.760> X<02:00:21.060> and<02:00:22.020> if<02:00:22.619> you 02:00:22.850 --> 02:00:22.860 align:start position:0% hush for a specific block X and if you 02:00:22.860 --> 02:00:24.950 align:start position:0% hush for a specific block X and if you follow<02:00:23.280> the<02:00:23.639> initial<02:00:23.940> slides<02:00:24.420> that's 02:00:24.950 --> 02:00:24.960 align:start position:0% follow the initial slides that's 02:00:24.960 --> 02:00:26.870 align:start position:0% follow the initial slides that's essentially<02:00:25.380> each<02:00:25.739> block<02:00:26.040> we<02:00:26.400> given<02:00:26.760> a 02:00:26.870 --> 02:00:26.880 align:start position:0% essentially each block we given a 02:00:26.880 --> 02:00:28.070 align:start position:0% essentially each block we given a blockage<02:00:27.179> you<02:00:27.420> can<02:00:27.480> recreate<02:00:27.840> the<02:00:27.960> block 02:00:28.070 --> 02:00:28.080 align:start position:0% blockage you can recreate the block 02:00:28.080 --> 02:00:30.350 align:start position:0% blockage you can recreate the block header<02:00:28.560> and<02:00:29.099> knowing<02:00:29.460> the<02:00:29.580> block<02:00:29.699> header<02:00:30.179> we 02:00:30.350 --> 02:00:30.360 align:start position:0% header and knowing the block header we 02:00:30.360 --> 02:00:31.430 align:start position:0% header and knowing the block header we can 02:00:31.430 --> 02:00:31.440 align:start position:0% can 02:00:31.440 --> 02:00:33.589 align:start position:0% can access<02:00:32.040> the<02:00:32.340> parent<02:00:32.460> question<02:00:32.820> by<02:00:33.300> knowing 02:00:33.589 --> 02:00:33.599 align:start position:0% access the parent question by knowing 02:00:33.599 --> 02:00:34.910 align:start position:0% access the parent question by knowing the<02:00:33.659> parent<02:00:33.780> hash<02:00:34.139> you<02:00:34.320> can<02:00:34.380> recreate<02:00:34.800> the 02:00:34.910 --> 02:00:34.920 align:start position:0% the parent hash you can recreate the 02:00:34.920 --> 02:00:36.890 align:start position:0% the parent hash you can recreate the previous<02:00:35.040> block<02:00:35.280> header<02:00:35.760> to<02:00:36.119> essentially<02:00:36.540> go 02:00:36.890 --> 02:00:36.900 align:start position:0% previous block header to essentially go 02:00:36.900 --> 02:00:40.010 align:start position:0% previous block header to essentially go to<02:00:37.139> the<02:00:37.380> Genesis<02:00:38.040> block<02:00:38.760> so<02:00:39.239> given<02:00:39.599> this<02:00:39.840> very 02:00:40.010 --> 02:00:40.020 align:start position:0% to the Genesis block so given this very 02:00:40.020 --> 02:00:41.990 align:start position:0% to the Genesis block so given this very small<02:00:40.260> input<02:00:40.679> we<02:00:40.980> can<02:00:41.099> essentially<02:00:41.460> unroll 02:00:41.990 --> 02:00:42.000 align:start position:0% small input we can essentially unroll 02:00:42.000 --> 02:00:44.149 align:start position:0% small input we can essentially unroll the<02:00:42.420> state<02:00:42.659> or<02:00:42.960> whatever<02:00:43.139> was<02:00:43.500> present<02:00:43.800> on<02:00:43.980> the 02:00:44.149 --> 02:00:44.159 align:start position:0% the state or whatever was present on the 02:00:44.159 --> 02:00:46.490 align:start position:0% the state or whatever was present on the chain<02:00:44.280> from<02:00:44.880> this<02:00:45.000> block<02:00:45.239> till<02:00:45.840> the<02:00:46.080> Journey's 02:00:46.490 --> 02:00:46.500 align:start position:0% chain from this block till the Journey's 02:00:46.500 --> 02:00:47.629 align:start position:0% chain from this block till the Journey's block 02:00:47.629 --> 02:00:47.639 align:start position:0% block 02:00:47.639 --> 02:00:50.930 align:start position:0% block okay<02:00:48.119> so<02:00:49.020> as<02:00:49.860> I<02:00:49.980> said<02:00:50.159> I'm<02:00:50.460> gonna<02:00:50.639> explain 02:00:50.930 --> 02:00:50.940 align:start position:0% okay so as I said I'm gonna explain 02:00:50.940 --> 02:00:53.870 align:start position:0% okay so as I said I'm gonna explain everything<02:00:51.480> on<02:00:52.380> on<02:00:52.800> the<02:00:52.980> example<02:00:53.219> of<02:00:53.400> ethereum 02:00:53.870 --> 02:00:53.880 align:start position:0% everything on on the example of ethereum 02:00:53.880 --> 02:00:57.229 align:start position:0% everything on on the example of ethereum and<02:00:54.599> today<02:00:55.199> all<02:00:55.739> the<02:00:55.980> block<02:00:56.099> headers<02:00:56.580> together 02:00:57.229 --> 02:00:57.239 align:start position:0% and today all the block headers together 02:00:57.239 --> 02:01:00.830 align:start position:0% and today all the block headers together are<02:00:57.719> like<02:00:57.960> roughly<02:00:58.500> seven<02:00:58.800> gigabytes<02:00:59.280> of<02:00:59.460> data 02:01:00.830 --> 02:01:00.840 align:start position:0% are like roughly seven gigabytes of data 02:01:00.840 --> 02:01:03.589 align:start position:0% are like roughly seven gigabytes of data so<02:01:01.199> it's<02:01:01.380> quite<02:01:01.560> a<02:01:01.739> lot<02:01:01.800> but<02:01:02.699> okay<02:01:02.820> this<02:01:03.239> is<02:01:03.300> how 02:01:03.589 --> 02:01:03.599 align:start position:0% so it's quite a lot but okay this is how 02:01:03.599 --> 02:01:05.149 align:start position:0% so it's quite a lot but okay this is how we<02:01:03.780> actually<02:01:04.199> do<02:01:04.560> that<02:01:04.679> this<02:01:04.860> is<02:01:04.920> the<02:01:05.040> high 02:01:05.149 --> 02:01:05.159 align:start position:0% we actually do that this is the high 02:01:05.159 --> 02:01:06.530 align:start position:0% we actually do that this is the high level<02:01:05.340> concept<02:01:05.820> and<02:01:06.060> what<02:01:06.239> are<02:01:06.420> the 02:01:06.530 --> 02:01:06.540 align:start position:0% level concept and what are the 02:01:06.540 --> 02:01:07.550 align:start position:0% level concept and what are the approaches 02:01:07.550 --> 02:01:07.560 align:start position:0% approaches 02:01:07.560 --> 02:01:09.350 align:start position:0% approaches so<02:01:08.159> the<02:01:08.400> first<02:01:08.520> one<02:01:08.699> we<02:01:08.880> call<02:01:09.000> it<02:01:09.179> like 02:01:09.350 --> 02:01:09.360 align:start position:0% so the first one we call it like 02:01:09.360 --> 02:01:11.629 align:start position:0% so the first one we call it like on-train<02:01:09.780> accumulation<02:01:10.320> so<02:01:10.980> essentially<02:01:11.400> we 02:01:11.629 --> 02:01:11.639 align:start position:0% on-train accumulation so essentially we 02:01:11.639 --> 02:01:13.609 align:start position:0% on-train accumulation so essentially we do<02:01:11.820> this<02:01:12.119> procedure<02:01:12.780> this<02:01:13.139> computation 02:01:13.609 --> 02:01:13.619 align:start position:0% do this procedure this computation 02:01:13.619 --> 02:01:16.490 align:start position:0% do this procedure this computation directly<02:01:14.520> on<02:01:14.699> the<02:01:14.820> Chain<02:01:15.000> so<02:01:15.300> we<02:01:15.480> provide<02:01:15.840> all 02:01:16.490 --> 02:01:16.500 align:start position:0% directly on the Chain so we provide all 02:01:16.500 --> 02:01:18.229 align:start position:0% directly on the Chain so we provide all these<02:01:16.800> properly<02:01:17.159> encoded<02:01:17.639> block<02:01:17.760> headers 02:01:18.229 --> 02:01:18.239 align:start position:0% these properly encoded block headers 02:01:18.239 --> 02:01:20.629 align:start position:0% these properly encoded block headers inside<02:01:19.080> the<02:01:19.320> call<02:01:19.440> data 02:01:20.629 --> 02:01:20.639 align:start position:0% inside the call data 02:01:20.639 --> 02:01:23.209 align:start position:0% inside the call data and<02:01:21.420> the<02:01:21.960> blockers<02:01:22.260> that<02:01:22.500> we<02:01:22.619> might<02:01:22.860> receive 02:01:23.209 --> 02:01:23.219 align:start position:0% and the blockers that we might receive 02:01:23.219 --> 02:01:25.310 align:start position:0% and the blockers that we might receive as<02:01:23.520> like<02:01:23.699> The<02:01:23.820> Trusted<02:01:24.239> input<02:01:24.540> by<02:01:24.840> sending<02:01:25.139> a 02:01:25.310 --> 02:01:25.320 align:start position:0% as like The Trusted input by sending a 02:01:25.320 --> 02:01:27.530 align:start position:0% as like The Trusted input by sending a message<02:01:25.500> relaying<02:01:26.400> it<02:01:26.460> in<02:01:26.580> optimistic<02:01:27.179> manner 02:01:27.530 --> 02:01:27.540 align:start position:0% message relaying it in optimistic manner 02:01:27.540 --> 02:01:29.990 align:start position:0% message relaying it in optimistic manner or<02:01:27.960> validating<02:01:28.380> the<02:01:28.619> consensus 02:01:29.990 --> 02:01:30.000 align:start position:0% or validating the consensus 02:01:30.000 --> 02:01:33.050 align:start position:0% or validating the consensus and<02:01:30.900> yeah<02:01:31.440> like<02:01:31.739> recursively<02:01:32.400> go<02:01:32.639> through<02:01:32.820> all 02:01:33.050 --> 02:01:33.060 align:start position:0% and yeah like recursively go through all 02:01:33.060 --> 02:01:35.629 align:start position:0% and yeah like recursively go through all these<02:01:33.239> headers<02:01:33.659> and<02:01:34.260> and<02:01:34.380> verify<02:01:34.800> them<02:01:35.040> but 02:01:35.629 --> 02:01:35.639 align:start position:0% these headers and and verify them but 02:01:35.639 --> 02:01:38.270 align:start position:0% these headers and and verify them but there<02:01:36.179> are<02:01:36.360> many<02:01:36.780> many<02:01:36.960> downsides<02:01:37.739> because 02:01:38.270 --> 02:01:38.280 align:start position:0% there are many many downsides because 02:01:38.280 --> 02:01:40.609 align:start position:0% there are many many downsides because first<02:01:38.639> of<02:01:38.760> all<02:01:38.880> it's<02:01:39.599> very<02:01:39.960> cool<02:01:40.199> data 02:01:40.609 --> 02:01:40.619 align:start position:0% first of all it's very cool data 02:01:40.619 --> 02:01:42.290 align:start position:0% first of all it's very cool data intensive<02:01:41.159> it's<02:01:41.639> very<02:01:41.880> computational 02:01:42.290 --> 02:01:42.300 align:start position:0% intensive it's very computational 02:01:42.300 --> 02:01:44.990 align:start position:0% intensive it's very computational intensive<02:01:43.080> and<02:01:43.679> now<02:01:43.860> we<02:01:44.040> can<02:01:44.219> store<02:01:44.460> all<02:01:44.820> these 02:01:44.990 --> 02:01:45.000 align:start position:0% intensive and now we can store all these 02:01:45.000 --> 02:01:47.450 align:start position:0% intensive and now we can store all these headers<02:01:45.360> on<02:01:46.080> the<02:01:46.199> actual<02:01:46.500> chain<02:01:46.739> but<02:01:47.040> you<02:01:47.340> know 02:01:47.450 --> 02:01:47.460 align:start position:0% headers on the actual chain but you know 02:01:47.460 --> 02:01:49.010 align:start position:0% headers on the actual chain but you know even<02:01:47.699> storing 02:01:49.010 --> 02:01:49.020 align:start position:0% even storing 02:01:49.020 --> 02:01:52.910 align:start position:0% even storing on<02:01:49.560> an<02:01:49.679> L2<02:01:50.099> storing<02:01:51.060> 7<02:01:51.179> gigabytes<02:01:51.719> of<02:01:51.840> data<02:01:52.260> is 02:01:52.910 --> 02:01:52.920 align:start position:0% on an L2 storing 7 gigabytes of data is 02:01:52.920 --> 02:01:55.129 align:start position:0% on an L2 storing 7 gigabytes of data is still<02:01:53.159> a<02:01:53.400> significant<02:01:53.760> cost<02:01:54.000> because<02:01:54.360> the 02:01:55.129 --> 02:01:55.139 align:start position:0% still a significant cost because the 02:01:55.139 --> 02:01:57.530 align:start position:0% still a significant cost because the state<02:01:55.320> on<02:01:55.500> an<02:01:55.679> L2<02:01:55.980> is<02:01:56.099> reflected<02:01:56.580> as<02:01:56.820> call<02:01:57.179> data 02:01:57.530 --> 02:01:57.540 align:start position:0% state on an L2 is reflected as call data 02:01:57.540 --> 02:02:01.430 align:start position:0% state on an L2 is reflected as call data on<02:01:57.659> L1<02:01:58.020> so<02:01:58.800> it's<02:01:59.520> still<02:01:59.880> expensive<02:02:00.420> either<02:02:00.659> way 02:02:01.430 --> 02:02:01.440 align:start position:0% on L1 so it's still expensive either way 02:02:01.440 --> 02:02:03.410 align:start position:0% on L1 so it's still expensive either way but<02:02:01.920> the<02:02:02.040> cool<02:02:02.159> thing<02:02:02.460> is<02:02:02.639> that<02:02:02.760> I<02:02:02.940> have<02:02:03.119> direct 02:02:03.410 --> 02:02:03.420 align:start position:0% but the cool thing is that I have direct 02:02:03.420 --> 02:02:06.169 align:start position:0% but the cool thing is that I have direct access<02:02:03.780> to<02:02:04.560> like<02:02:05.099> State<02:02:05.400> router<02:02:05.820> or<02:02:06.000> anything 02:02:06.169 --> 02:02:06.179 align:start position:0% access to like State router or anything 02:02:06.179 --> 02:02:09.290 align:start position:0% access to like State router or anything that<02:02:06.480> I<02:02:06.599> want<02:02:06.780> to<02:02:06.900> access 02:02:09.290 --> 02:02:09.300 align:start position:0% 02:02:09.300 --> 02:02:13.189 align:start position:0% next<02:02:09.780> approach<02:02:10.199> is<02:02:11.099> unchain<02:02:11.580> compression 02:02:13.189 --> 02:02:13.199 align:start position:0% next approach is unchain compression 02:02:13.199 --> 02:02:16.070 align:start position:0% next approach is unchain compression so<02:02:13.800> we<02:02:14.280> can<02:02:14.520> still<02:02:14.880> use<02:02:15.300> the<02:02:15.540> same<02:02:15.659> approaches 02:02:16.070 --> 02:02:16.080 align:start position:0% so we can still use the same approaches 02:02:16.080 --> 02:02:19.430 align:start position:0% so we can still use the same approaches previously<02:02:16.560> so<02:02:16.980> literally<02:02:17.340> unroll<02:02:17.760> it<02:02:18.480> and 02:02:19.430 --> 02:02:19.440 align:start position:0% previously so literally unroll it and 02:02:19.440 --> 02:02:21.709 align:start position:0% previously so literally unroll it and process<02:02:20.040> this<02:02:20.340> seven<02:02:20.580> gigabytes<02:02:21.119> of<02:02:21.239> data<02:02:21.540> but 02:02:21.709 --> 02:02:21.719 align:start position:0% process this seven gigabytes of data but 02:02:21.719 --> 02:02:23.810 align:start position:0% process this seven gigabytes of data but instead<02:02:22.080> of<02:02:22.139> like<02:02:22.320> storing<02:02:22.800> then<02:02:23.340> we<02:02:23.580> can<02:02:23.639> just 02:02:23.810 --> 02:02:23.820 align:start position:0% instead of like storing then we can just 02:02:23.820 --> 02:02:25.790 align:start position:0% instead of like storing then we can just update<02:02:24.119> the<02:02:24.300> miracle<02:02:24.599> tree<02:02:24.780> it's<02:02:25.440> a<02:02:25.679> nice 02:02:25.790 --> 02:02:25.800 align:start position:0% update the miracle tree it's a nice 02:02:25.800 --> 02:02:27.770 align:start position:0% update the miracle tree it's a nice approach<02:02:26.159> but<02:02:26.460> comes<02:02:26.940> again<02:02:27.119> with<02:02:27.360> a<02:02:27.540> few<02:02:27.599> dump 02:02:27.770 --> 02:02:27.780 align:start position:0% approach but comes again with a few dump 02:02:27.780 --> 02:02:30.350 align:start position:0% approach but comes again with a few dump sites<02:02:28.199> it's<02:02:28.920> very<02:02:29.159> computationally<02:02:29.820> intense 02:02:30.350 --> 02:02:30.360 align:start position:0% sites it's very computationally intense 02:02:30.360 --> 02:02:31.970 align:start position:0% sites it's very computationally intense because<02:02:30.719> if<02:02:31.139> we<02:02:31.199> have<02:02:31.380> like<02:02:31.500> millions<02:02:31.860> of 02:02:31.970 --> 02:02:31.980 align:start position:0% because if we have like millions of 02:02:31.980 --> 02:02:34.129 align:start position:0% because if we have like millions of headers<02:02:32.340> we<02:02:32.580> need<02:02:32.760> to<02:02:32.880> perform<02:02:33.360> millions<02:02:33.960> of 02:02:34.129 --> 02:02:34.139 align:start position:0% headers we need to perform millions of 02:02:34.139 --> 02:02:36.530 align:start position:0% headers we need to perform millions of hashes<02:02:34.560> on<02:02:34.980> the<02:02:35.099> Chain<02:02:35.300> that's<02:02:36.300> that's 02:02:36.530 --> 02:02:36.540 align:start position:0% hashes on the Chain that's that's 02:02:36.540 --> 02:02:39.169 align:start position:0% hashes on the Chain that's that's expensive<02:02:37.139> but<02:02:37.619> at<02:02:37.739> least<02:02:37.920> we<02:02:38.159> we<02:02:38.460> save<02:02:38.699> on<02:02:39.000> on 02:02:39.169 --> 02:02:39.179 align:start position:0% expensive but at least we we save on on 02:02:39.179 --> 02:02:42.169 align:start position:0% expensive but at least we we save on on storing<02:02:39.659> data<02:02:40.460> and<02:02:41.460> also<02:02:41.639> we<02:02:41.760> need<02:02:41.880> to<02:02:41.940> update 02:02:42.169 --> 02:02:42.179 align:start position:0% storing data and also we need to update 02:02:42.179 --> 02:02:43.550 align:start position:0% storing data and also we need to update the<02:02:42.300> miracle<02:02:42.599> tree<02:02:42.780> which<02:02:43.020> is<02:02:43.080> which<02:02:43.380> is 02:02:43.550 --> 02:02:43.560 align:start position:0% the miracle tree which is which is 02:02:43.560 --> 02:02:45.470 align:start position:0% the miracle tree which is which is another<02:02:43.679> cost 02:02:45.470 --> 02:02:45.480 align:start position:0% another cost 02:02:45.480 --> 02:02:46.129 align:start position:0% another cost um 02:02:46.129 --> 02:02:46.139 align:start position:0% um 02:02:46.139 --> 02:02:49.070 align:start position:0% um last<02:02:46.739> downside<02:02:47.219> is<02:02:48.000> that<02:02:48.179> we<02:02:48.300> need<02:02:48.480> to<02:02:48.659> index 02:02:49.070 --> 02:02:49.080 align:start position:0% last downside is that we need to index 02:02:49.080 --> 02:02:50.930 align:start position:0% last downside is that we need to index all<02:02:49.500> the<02:02:49.619> headers<02:02:49.920> that<02:02:50.099> have<02:02:50.280> been<02:02:50.460> processed 02:02:50.930 --> 02:02:50.940 align:start position:0% all the headers that have been processed 02:02:50.940 --> 02:02:53.030 align:start position:0% all the headers that have been processed why<02:02:51.360> we<02:02:51.599> need<02:02:51.719> to<02:02:51.780> index<02:02:52.080> them<02:02:52.320> because<02:02:52.500> if<02:02:52.860> I 02:02:53.030 --> 02:02:53.040 align:start position:0% why we need to index them because if I 02:02:53.040 --> 02:02:54.109 align:start position:0% why we need to index them because if I want<02:02:53.219> to 02:02:54.109 --> 02:02:54.119 align:start position:0% want to 02:02:54.119 --> 02:02:58.010 align:start position:0% want to up<02:02:54.659> the<02:02:54.900> access<02:02:55.440> a<02:02:56.219> specific<02:02:56.580> block<02:02:56.820> header<02:02:57.300> I 02:02:58.010 --> 02:02:58.020 align:start position:0% up the access a specific block header I 02:02:58.020 --> 02:02:59.450 align:start position:0% up the access a specific block header I need<02:02:58.139> to<02:02:58.260> provide<02:02:58.500> a<02:02:58.619> miracle<02:02:58.980> tab<02:02:59.219> because<02:02:59.340> as 02:02:59.450 --> 02:02:59.460 align:start position:0% need to provide a miracle tab because as 02:02:59.460 --> 02:03:01.729 align:start position:0% need to provide a miracle tab because as we<02:02:59.639> update<02:02:59.880> the<02:03:00.060> miracle<02:03:00.360> 3<02:03:00.480> and<02:03:01.440> we<02:03:01.560> just 02:03:01.729 --> 02:03:01.739 align:start position:0% we update the miracle 3 and we just 02:03:01.739 --> 02:03:03.830 align:start position:0% we update the miracle 3 and we just store<02:03:01.920> the<02:03:02.159> root<02:03:02.280> in<02:03:03.060> the<02:03:03.239> contract<02:03:03.480> itself 02:03:03.830 --> 02:03:03.840 align:start position:0% store the root in the contract itself 02:03:03.840 --> 02:03:05.510 align:start position:0% store the root in the contract itself then<02:03:04.199> I<02:03:04.380> need<02:03:04.440> to<02:03:04.560> know<02:03:04.619> the<02:03:04.800> path<02:03:04.920> right<02:03:05.159> so<02:03:05.400> I 02:03:05.510 --> 02:03:05.520 align:start position:0% then I need to know the path right so I 02:03:05.520 --> 02:03:07.790 align:start position:0% then I need to know the path right so I need<02:03:05.639> to<02:03:05.760> index<02:03:06.300> the<02:03:06.540> data<02:03:06.900> and<02:03:07.020> essentially 02:03:07.790 --> 02:03:07.800 align:start position:0% need to index the data and essentially 02:03:07.800 --> 02:03:09.950 align:start position:0% need to index the data and essentially once<02:03:08.639> I<02:03:08.820> it's<02:03:09.119> the<02:03:09.300> moment<02:03:09.480> that<02:03:09.659> I<02:03:09.780> want<02:03:09.900> to 02:03:09.950 --> 02:03:09.960 align:start position:0% once I it's the moment that I want to 02:03:09.960 --> 02:03:12.109 align:start position:0% once I it's the moment that I want to access<02:03:10.080> it<02:03:10.320> I<02:03:10.500> need<02:03:10.619> to<02:03:10.679> provide<02:03:10.980> the<02:03:11.219> miracle 02:03:12.109 --> 02:03:12.119 align:start position:0% access it I need to provide the miracle 02:03:12.119 --> 02:03:13.129 align:start position:0% access it I need to provide the miracle path 02:03:13.129 --> 02:03:13.139 align:start position:0% path 02:03:13.139 --> 02:03:15.709 align:start position:0% path this<02:03:13.560> approach<02:03:13.860> is<02:03:14.040> okay<02:03:14.400> it's 02:03:15.709 --> 02:03:15.719 align:start position:0% this approach is okay it's 02:03:15.719 --> 02:03:17.390 align:start position:0% this approach is okay it's I<02:03:16.260> wouldn't<02:03:16.440> say<02:03:16.619> way<02:03:16.800> better<02:03:17.040> than<02:03:17.219> the 02:03:17.390 --> 02:03:17.400 align:start position:0% I wouldn't say way better than the 02:03:17.400 --> 02:03:21.589 align:start position:0% I wouldn't say way better than the previous<02:03:17.580> one<02:03:17.820> but<02:03:18.239> it's<02:03:18.840> way<02:03:19.320> cheaper 02:03:21.589 --> 02:03:21.599 align:start position:0% previous one but it's way cheaper 02:03:21.599 --> 02:03:23.330 align:start position:0% previous one but it's way cheaper last<02:03:22.199> approach 02:03:23.330 --> 02:03:23.340 align:start position:0% last approach 02:03:23.340 --> 02:03:25.790 align:start position:0% last approach so<02:03:23.820> there<02:03:24.119> is<02:03:24.300> a<02:03:24.540> very<02:03:24.659> cool<02:03:24.900> primitive<02:03:25.440> called 02:03:25.790 --> 02:03:25.800 align:start position:0% so there is a very cool primitive called 02:03:25.800 --> 02:03:27.890 align:start position:0% so there is a very cool primitive called Merkel<02:03:26.340> mountain<02:03:26.520> ranges 02:03:27.890 --> 02:03:27.900 align:start position:0% Merkel mountain ranges 02:03:27.900 --> 02:03:31.129 align:start position:0% Merkel mountain ranges love<02:03:28.560> it<02:03:28.800> and<02:03:29.639> the<02:03:29.820> idea<02:03:30.060> is<02:03:30.239> let's<02:03:30.599> do<02:03:30.900> the 02:03:31.129 --> 02:03:31.139 align:start position:0% love it and the idea is let's do the 02:03:31.139 --> 02:03:32.510 align:start position:0% love it and the idea is let's do the same 02:03:32.510 --> 02:03:32.520 align:start position:0% same 02:03:32.520 --> 02:03:35.510 align:start position:0% same that<02:03:32.940> we<02:03:33.119> do<02:03:33.239> previously<02:03:33.719> inside<02:03:34.080> this<02:03:34.320> Arc<02:03:34.800> so 02:03:35.510 --> 02:03:35.520 align:start position:0% that we do previously inside this Arc so 02:03:35.520 --> 02:03:38.089 align:start position:0% that we do previously inside this Arc so we<02:03:35.699> can<02:03:35.820> provide<02:03:36.239> this<02:03:36.960> tremendous<02:03:37.679> amount<02:03:37.980> of 02:03:38.089 --> 02:03:38.099 align:start position:0% we can provide this tremendous amount of 02:03:38.099 --> 02:03:41.149 align:start position:0% we can provide this tremendous amount of data<02:03:38.520> as<02:03:39.060> a<02:03:39.239> private<02:03:39.480> input<02:03:39.719> to<02:03:39.840> the<02:03:40.020> circuit 02:03:41.149 --> 02:03:41.159 align:start position:0% data as a private input to the circuit 02:03:41.159 --> 02:03:43.430 align:start position:0% data as a private input to the circuit and<02:03:41.820> essentially<02:03:42.300> do<02:03:42.659> the<02:03:42.780> same<02:03:42.960> computation 02:03:43.430 --> 02:03:43.440 align:start position:0% and essentially do the same computation 02:03:43.440 --> 02:03:46.370 align:start position:0% and essentially do the same computation like<02:03:43.679> unrolling<02:03:44.420> inside<02:03:45.420> this<02:03:45.659> record<02:03:45.900> itself 02:03:46.370 --> 02:03:46.380 align:start position:0% like unrolling inside this record itself 02:03:46.380 --> 02:03:48.950 align:start position:0% like unrolling inside this record itself and<02:03:46.980> now<02:03:47.159> we<02:03:47.820> have<02:03:47.940> a<02:03:48.060> public<02:03:48.239> input<02:03:48.599> which<02:03:48.840> is 02:03:48.950 --> 02:03:48.960 align:start position:0% and now we have a public input which is 02:03:48.960 --> 02:03:50.209 align:start position:0% and now we have a public input which is the<02:03:49.080> blockage<02:03:49.440> so<02:03:49.679> essentially<02:03:50.040> the 02:03:50.209 --> 02:03:50.219 align:start position:0% the blockage so essentially the 02:03:50.219 --> 02:03:52.790 align:start position:0% the blockage so essentially the commitment<02:03:50.580> from<02:03:50.880> which<02:03:51.060> we<02:03:51.360> unroll<02:03:52.020> it 02:03:52.790 --> 02:03:52.800 align:start position:0% commitment from which we unroll it 02:03:52.800 --> 02:03:55.189 align:start position:0% commitment from which we unroll it so<02:03:53.520> the<02:03:53.820> trusted<02:03:54.179> input<02:03:54.480> the<02:03:54.659> public<02:03:54.780> input 02:03:55.189 --> 02:03:55.199 align:start position:0% so the trusted input the public input 02:03:55.199 --> 02:03:56.870 align:start position:0% so the trusted input the public input can<02:03:55.380> be<02:03:55.560> literally<02:03:55.860> asserted<02:03:56.400> when<02:03:56.580> we<02:03:56.699> do<02:03:56.820> the 02:03:56.870 --> 02:03:56.880 align:start position:0% can be literally asserted when we do the 02:03:56.880 --> 02:03:58.609 align:start position:0% can be literally asserted when we do the on-train<02:03:57.300> verification 02:03:58.609 --> 02:03:58.619 align:start position:0% on-train verification 02:03:58.619 --> 02:04:00.830 align:start position:0% on-train verification and<02:03:59.159> why<02:03:59.340> we<02:03:59.460> unroll<02:03:59.820> it<02:04:00.060> we<02:04:00.239> can<02:04:00.360> accumulate 02:04:00.830 --> 02:04:00.840 align:start position:0% and why we unroll it we can accumulate 02:04:00.840 --> 02:04:02.930 align:start position:0% and why we unroll it we can accumulate inside<02:04:01.020> the<02:04:01.260> miracle<02:04:01.560> tree<02:04:01.800> or<02:04:02.639> American 02:04:02.930 --> 02:04:02.940 align:start position:0% inside the miracle tree or American 02:04:02.940 --> 02:04:04.850 align:start position:0% inside the miracle tree or American mountain<02:04:03.360> range<02:04:03.780> why<02:04:04.139> American<02:04:04.440> mountain 02:04:04.850 --> 02:04:04.860 align:start position:0% mountain range why American mountain 02:04:04.860 --> 02:04:07.370 align:start position:0% mountain range why American mountain range<02:04:05.340> is<02:04:05.699> is<02:04:05.940> cool<02:04:06.239> because<02:04:06.599> well<02:04:06.900> let's 02:04:07.370 --> 02:04:07.380 align:start position:0% range is is cool because well let's 02:04:07.380 --> 02:04:09.709 align:start position:0% range is is cool because well let's imagine<02:04:07.560> that<02:04:07.860> you<02:04:07.980> want<02:04:08.159> to<02:04:08.280> have<02:04:08.460> like<02:04:08.760> seven 02:04:09.709 --> 02:04:09.719 align:start position:0% imagine that you want to have like seven 02:04:09.719 --> 02:04:11.689 align:start position:0% imagine that you want to have like seven gigabytes<02:04:10.500> of<02:04:10.619> data<02:04:10.920> processing<02:04:11.280> one<02:04:11.520> star 02:04:11.689 --> 02:04:11.699 align:start position:0% gigabytes of data processing one star 02:04:11.699 --> 02:04:13.370 align:start position:0% gigabytes of data processing one star like<02:04:11.880> the<02:04:12.060> proving<02:04:12.300> time<02:04:12.480> is<02:04:12.659> going<02:04:13.020> to<02:04:13.139> be 02:04:13.370 --> 02:04:13.380 align:start position:0% like the proving time is going to be 02:04:13.380 --> 02:04:15.229 align:start position:0% like the proving time is going to be horrible<02:04:13.739> and<02:04:14.040> why<02:04:14.280> would<02:04:14.580> you<02:04:14.820> even<02:04:14.880> like 02:04:15.229 --> 02:04:15.239 align:start position:0% horrible and why would you even like 02:04:15.239 --> 02:04:18.050 align:start position:0% horrible and why would you even like prove<02:04:16.560> this<02:04:16.980> commitment<02:04:17.400> for<02:04:17.699> like<02:04:17.880> the 02:04:18.050 --> 02:04:18.060 align:start position:0% prove this commitment for like the 02:04:18.060 --> 02:04:19.850 align:start position:0% prove this commitment for like the entire<02:04:18.360> history<02:04:18.599> like<02:04:19.139> do<02:04:19.320> you<02:04:19.500> really<02:04:19.619> need 02:04:19.850 --> 02:04:19.860 align:start position:0% entire history like do you really need 02:04:19.860 --> 02:04:23.390 align:start position:0% entire history like do you really need that<02:04:20.040> probably<02:04:20.639> not<02:04:20.940> so<02:04:21.840> let's<02:04:22.560> chunk<02:04:23.040> it<02:04:23.219> like 02:04:23.390 --> 02:04:23.400 align:start position:0% that probably not so let's chunk it like 02:04:23.400 --> 02:04:25.430 align:start position:0% that probably not so let's chunk it like into<02:04:23.580> smaller<02:04:24.000> pieces<02:04:24.420> and<02:04:24.900> Miracle<02:04:25.320> mountain 02:04:25.430 --> 02:04:25.440 align:start position:0% into smaller pieces and Miracle mountain 02:04:25.440 --> 02:04:27.830 align:start position:0% into smaller pieces and Miracle mountain ranges<02:04:26.040> are<02:04:26.280> pretty<02:04:26.580> cool<02:04:26.760> primitive<02:04:27.239> that 02:04:27.830 --> 02:04:27.840 align:start position:0% ranges are pretty cool primitive that 02:04:27.840 --> 02:04:30.589 align:start position:0% ranges are pretty cool primitive that allow<02:04:28.139> to<02:04:28.380> do<02:04:28.440> this<02:04:28.619> to<02:04:29.040> do<02:04:29.219> to<02:04:29.340> do<02:04:29.580> this 02:04:30.589 --> 02:04:30.599 align:start position:0% allow to do this to do to do this 02:04:30.599 --> 02:04:34.070 align:start position:0% allow to do this to do to do this to<02:04:31.080> give<02:04:31.260> you<02:04:31.380> like<02:04:31.619> a<02:04:32.159> bit<02:04:32.460> of<02:04:32.580> intuition<02:04:33.080> how 02:04:34.070 --> 02:04:34.080 align:start position:0% to give you like a bit of intuition how 02:04:34.080 --> 02:04:36.410 align:start position:0% to give you like a bit of intuition how how<02:04:34.260> does<02:04:34.440> it<02:04:34.619> work<02:04:34.800> it's<02:04:35.520> essential<02:04:35.940> think<02:04:36.239> of 02:04:36.410 --> 02:04:36.420 align:start position:0% how does it work it's essential think of 02:04:36.420 --> 02:04:38.810 align:start position:0% how does it work it's essential think of it<02:04:36.540> as<02:04:36.719> a<02:04:36.900> tree<02:04:37.020> of<02:04:37.260> trees 02:04:38.810 --> 02:04:38.820 align:start position:0% it as a tree of trees 02:04:38.820 --> 02:04:41.330 align:start position:0% it as a tree of trees um<02:04:38.940> yeah<02:04:39.239> so<02:04:39.659> once<02:04:40.380> we<02:04:40.440> do<02:04:40.619> all<02:04:40.800> this<02:04:40.920> proving 02:04:41.330 --> 02:04:41.340 align:start position:0% um yeah so once we do all this proving 02:04:41.340 --> 02:04:43.490 align:start position:0% um yeah so once we do all this proving like<02:04:41.460> of<02:04:41.699> chain<02:04:41.940> we<02:04:42.300> simply<02:04:42.659> verify<02:04:43.080> the<02:04:43.199> proof 02:04:43.490 --> 02:04:43.500 align:start position:0% like of chain we simply verify the proof 02:04:43.500 --> 02:04:45.470 align:start position:0% like of chain we simply verify the proof on<02:04:43.619> chain<02:04:43.920> as<02:04:44.580> you<02:04:44.699> know<02:04:44.820> like<02:04:44.940> refine<02:04:45.360> the 02:04:45.470 --> 02:04:45.480 align:start position:0% on chain as you know like refine the 02:04:45.480 --> 02:04:48.109 align:start position:0% on chain as you know like refine the proof<02:04:45.780> is<02:04:45.960> is<02:04:46.679> way<02:04:47.219> cheaper<02:04:47.520> than<02:04:47.699> doing<02:04:47.880> this 02:04:48.109 --> 02:04:48.119 align:start position:0% proof is is way cheaper than doing this 02:04:48.119 --> 02:04:49.669 align:start position:0% proof is is way cheaper than doing this directly<02:04:48.480> on<02:04:48.659> the<02:04:48.780> chain 02:04:49.669 --> 02:04:49.679 align:start position:0% directly on the chain 02:04:49.679 --> 02:04:52.669 align:start position:0% directly on the chain and<02:04:50.340> still<02:04:50.699> we<02:04:51.300> just<02:04:51.719> provide<02:04:52.020> a<02:04:52.139> miracle<02:04:52.500> path 02:04:52.669 --> 02:04:52.679 align:start position:0% and still we just provide a miracle path 02:04:52.679 --> 02:04:55.010 align:start position:0% and still we just provide a miracle path and<02:04:53.040> that's<02:04:53.159> it<02:04:53.820> we<02:04:54.239> essentially<02:04:54.599> have<02:04:54.840> access 02:04:55.010 --> 02:04:55.020 align:start position:0% and that's it we essentially have access 02:04:55.020 --> 02:04:57.350 align:start position:0% and that's it we essentially have access to<02:04:55.260> any<02:04:55.380> sort<02:04:55.619> of<02:04:55.739> data<02:04:56.040> we<02:04:56.159> want 02:04:57.350 --> 02:04:57.360 align:start position:0% to any sort of data we want 02:04:57.360 --> 02:05:00.709 align:start position:0% to any sort of data we want let's<02:04:57.780> do<02:04:58.020> a<02:04:58.139> recap<02:04:58.500> again<02:04:58.980> so<02:04:59.719> approach 02:05:00.709 --> 02:05:00.719 align:start position:0% let's do a recap again so approach 02:05:00.719 --> 02:05:03.290 align:start position:0% let's do a recap again so approach number<02:05:00.900> one<02:05:01.139> on<02:05:01.440> the<02:05:01.619> accumulation<02:05:02.159> on<02:05:03.000> chain 02:05:03.290 --> 02:05:03.300 align:start position:0% number one on the accumulation on chain 02:05:03.300 --> 02:05:06.229 align:start position:0% number one on the accumulation on chain compression<02:05:03.840> of<02:05:04.500> chain<02:05:04.800> compression<02:05:05.340> three 02:05:06.229 --> 02:05:06.239 align:start position:0% compression of chain compression three 02:05:06.239 --> 02:05:08.930 align:start position:0% compression of chain compression three categories<02:05:06.780> prover<02:05:07.440> overhead<02:05:07.920> gas<02:05:08.639> cost 02:05:08.930 --> 02:05:08.940 align:start position:0% categories prover overhead gas cost 02:05:08.940 --> 02:05:10.850 align:start position:0% categories prover overhead gas cost storage<02:05:09.540> cost 02:05:10.850 --> 02:05:10.860 align:start position:0% storage cost 02:05:10.860 --> 02:05:12.350 align:start position:0% storage cost actually<02:05:11.340> gas<02:05:11.760> costs<02:05:12.119> should<02:05:12.239> be 02:05:12.350 --> 02:05:12.360 align:start position:0% actually gas costs should be 02:05:12.360 --> 02:05:14.390 align:start position:0% actually gas costs should be computational<02:05:13.020> cost 02:05:14.390 --> 02:05:14.400 align:start position:0% computational cost 02:05:14.400 --> 02:05:16.370 align:start position:0% computational cost okay<02:05:14.820> so<02:05:15.060> prover<02:05:15.360> overhead<02:05:15.840> on-chain 02:05:16.370 --> 02:05:16.380 align:start position:0% okay so prover overhead on-chain 02:05:16.380 --> 02:05:18.350 align:start position:0% okay so prover overhead on-chain accumulation<02:05:16.800> do<02:05:17.400> we<02:05:17.520> prove<02:05:17.760> anything<02:05:17.940> well 02:05:18.350 --> 02:05:18.360 align:start position:0% accumulation do we prove anything well 02:05:18.360 --> 02:05:21.410 align:start position:0% accumulation do we prove anything well not<02:05:18.780> really<02:05:18.960> so<02:05:19.800> we<02:05:19.980> are<02:05:20.159> happy<02:05:20.420> answering 02:05:21.410 --> 02:05:21.420 align:start position:0% not really so we are happy answering 02:05:21.420 --> 02:05:27.050 align:start position:0% not really so we are happy answering compression<02:05:21.900> well 02:05:27.050 --> 02:05:27.060 align:start position:0% 02:05:27.060 --> 02:05:29.030 align:start position:0% we<02:05:27.599> still<02:05:27.780> like<02:05:28.020> need<02:05:28.199> to<02:05:28.320> update<02:05:28.619> the<02:05:28.679> miracle 02:05:29.030 --> 02:05:29.040 align:start position:0% we still like need to update the miracle 02:05:29.040 --> 02:05:31.250 align:start position:0% we still like need to update the miracle tree<02:05:29.099> I<02:05:29.460> think<02:05:29.520> actually<02:05:29.699> there<02:05:30.060> is<02:05:30.239> uh<02:05:30.719> there 02:05:31.250 --> 02:05:31.260 align:start position:0% tree I think actually there is uh there 02:05:31.260 --> 02:05:33.290 align:start position:0% tree I think actually there is uh there is<02:05:31.380> an<02:05:31.440> issue<02:05:31.739> here<02:05:31.920> so<02:05:32.400> I'll<02:05:32.639> just<02:05:32.880> skip<02:05:33.060> this 02:05:33.290 --> 02:05:33.300 align:start position:0% is an issue here so I'll just skip this 02:05:33.300 --> 02:05:35.870 align:start position:0% is an issue here so I'll just skip this part<02:05:33.480> after<02:05:33.960> in<02:05:34.320> compression<02:05:34.800> you're<02:05:35.460> very 02:05:35.870 --> 02:05:35.880 align:start position:0% part after in compression you're very 02:05:35.880 --> 02:05:38.689 align:start position:0% part after in compression you're very very<02:05:36.060> sad<02:05:36.480> because<02:05:36.960> well<02:05:37.800> we<02:05:38.099> need<02:05:38.219> to<02:05:38.340> prove 02:05:38.689 --> 02:05:38.699 align:start position:0% very sad because well we need to prove 02:05:38.699 --> 02:05:41.570 align:start position:0% very sad because well we need to prove actually<02:05:38.940> significant<02:05:39.900> computation<02:05:40.440> so<02:05:41.340> the 02:05:41.570 --> 02:05:41.580 align:start position:0% actually significant computation so the 02:05:41.580 --> 02:05:44.030 align:start position:0% actually significant computation so the proving<02:05:41.880> time<02:05:42.060> is<02:05:42.239> significant<02:05:42.719> okay<02:05:43.560> now<02:05:43.860> in 02:05:44.030 --> 02:05:44.040 align:start position:0% proving time is significant okay now in 02:05:44.040 --> 02:05:45.830 align:start position:0% proving time is significant okay now in terms<02:05:44.219> of<02:05:44.280> gas<02:05:44.520> cause<02:05:44.760> the<02:05:45.000> third<02:05:45.119> approach<02:05:45.540> is 02:05:45.830 --> 02:05:45.840 align:start position:0% terms of gas cause the third approach is 02:05:45.840 --> 02:05:47.570 align:start position:0% terms of gas cause the third approach is horrible<02:05:46.199> because<02:05:46.560> it<02:05:46.800> just<02:05:46.920> costs<02:05:47.340> a<02:05:47.460> lot 02:05:47.570 --> 02:05:47.580 align:start position:0% horrible because it just costs a lot 02:05:47.580 --> 02:05:49.669 align:start position:0% horrible because it just costs a lot because<02:05:48.179> we<02:05:48.480> do<02:05:48.659> the<02:05:48.780> entire<02:05:49.139> computation 02:05:49.669 --> 02:05:49.679 align:start position:0% because we do the entire computation 02:05:49.679 --> 02:05:52.550 align:start position:0% because we do the entire computation engine<02:05:50.520> compression<02:05:51.119> well<02:05:51.360> we're<02:05:52.080> a<02:05:52.440> bit 02:05:52.550 --> 02:05:52.560 align:start position:0% engine compression well we're a bit 02:05:52.560 --> 02:05:54.290 align:start position:0% engine compression well we're a bit happy<02:05:52.800> because<02:05:53.159> we<02:05:53.400> just<02:05:53.580> do<02:05:53.760> a<02:05:53.940> bit<02:05:54.119> of 02:05:54.290 --> 02:05:54.300 align:start position:0% happy because we just do a bit of 02:05:54.300 --> 02:05:56.990 align:start position:0% happy because we just do a bit of computation<02:05:54.960> but<02:05:55.500> still<02:05:55.920> it's<02:05:56.520> a<02:05:56.639> lot<02:05:56.760> of<02:05:56.880> cool 02:05:56.990 --> 02:05:57.000 align:start position:0% computation but still it's a lot of cool 02:05:57.000 --> 02:05:59.390 align:start position:0% computation but still it's a lot of cool data<02:05:57.360> a<02:05:57.540> lot<02:05:57.659> of<02:05:57.780> computation<02:05:58.260> but<02:05:58.619> at<02:05:59.280> least 02:05:59.390 --> 02:05:59.400 align:start position:0% data a lot of computation but at least 02:05:59.400 --> 02:06:02.629 align:start position:0% data a lot of computation but at least not<02:05:59.639> so<02:05:59.880> much<02:06:00.000> storage<02:06:00.320> storage<02:06:01.320> cost<02:06:01.739> uh<02:06:02.460> oh 02:06:02.629 --> 02:06:02.639 align:start position:0% not so much storage storage cost uh oh 02:06:02.639 --> 02:06:04.729 align:start position:0% not so much storage storage cost uh oh sorry<02:06:02.940> gas<02:06:03.300> cost<02:06:03.540> in<02:06:04.020> the<02:06:04.199> second<02:06:04.380> approach 02:06:04.729 --> 02:06:04.739 align:start position:0% sorry gas cost in the second approach 02:06:04.739 --> 02:06:06.290 align:start position:0% sorry gas cost in the second approach while<02:06:04.980> we<02:06:05.219> just<02:06:05.340> verify<02:06:05.699> approved<02:06:06.119> so<02:06:06.179> it's 02:06:06.290 --> 02:06:06.300 align:start position:0% while we just verify approved so it's 02:06:06.300 --> 02:06:07.850 align:start position:0% while we just verify approved so it's cool 02:06:07.850 --> 02:06:07.860 align:start position:0% cool 02:06:07.860 --> 02:06:10.070 align:start position:0% cool um<02:06:07.920> okay<02:06:08.280> storage<02:06:08.940> cost<02:06:09.300> for<02:06:09.780> the<02:06:09.960> first 02:06:10.070 --> 02:06:10.080 align:start position:0% um okay storage cost for the first 02:06:10.080 --> 02:06:13.010 align:start position:0% um okay storage cost for the first approach<02:06:10.440> well<02:06:10.800> seven<02:06:11.460> gigabytes<02:06:12.000> of<02:06:12.119> data<02:06:12.480> it 02:06:13.010 --> 02:06:13.020 align:start position:0% approach well seven gigabytes of data it 02:06:13.020 --> 02:06:15.350 align:start position:0% approach well seven gigabytes of data it is<02:06:13.139> horrible<02:06:13.500> so<02:06:13.860> we<02:06:13.980> are<02:06:14.159> very<02:06:14.280> set 02:06:15.350 --> 02:06:15.360 align:start position:0% is horrible so we are very set 02:06:15.360 --> 02:06:17.149 align:start position:0% is horrible so we are very set on<02:06:15.719> chain<02:06:15.960> compression 02:06:17.149 --> 02:06:17.159 align:start position:0% on chain compression 02:06:17.159 --> 02:06:19.790 align:start position:0% on chain compression uh<02:06:17.760> sorry<02:06:17.940> storage<02:06:18.900> cost<02:06:19.199> for<02:06:19.380> launching 02:06:19.790 --> 02:06:19.800 align:start position:0% uh sorry storage cost for launching 02:06:19.800 --> 02:06:21.950 align:start position:0% uh sorry storage cost for launching compression<02:06:20.280> we<02:06:20.639> just 02:06:21.950 --> 02:06:21.960 align:start position:0% compression we just 02:06:21.960 --> 02:06:23.810 align:start position:0% compression we just the root<02:06:22.560> of<02:06:22.679> the<02:06:22.800> miracle<02:06:23.040> tree<02:06:23.219> so<02:06:23.520> we<02:06:23.639> are 02:06:23.810 --> 02:06:23.820 align:start position:0% the root of the miracle tree so we are 02:06:23.820 --> 02:06:27.290 align:start position:0% the root of the miracle tree so we are happy<02:06:24.139> and<02:06:25.139> in<02:06:25.500> the<02:06:25.739> second<02:06:26.340> case<02:06:26.699> we're<02:06:26.940> even 02:06:27.290 --> 02:06:27.300 align:start position:0% happy and in the second case we're even 02:06:27.300 --> 02:06:29.149 align:start position:0% happy and in the second case we're even more<02:06:27.480> happy<02:06:27.719> because<02:06:28.020> we<02:06:28.320> again<02:06:28.679> we<02:06:28.980> just 02:06:29.149 --> 02:06:29.159 align:start position:0% more happy because we again we just 02:06:29.159 --> 02:06:31.310 align:start position:0% more happy because we again we just essentially<02:06:29.760> keep<02:06:30.000> updating<02:06:30.300> a<02:06:30.540> tree<02:06:30.780> and<02:06:31.020> we 02:06:31.310 --> 02:06:31.320 align:start position:0% essentially keep updating a tree and we 02:06:31.320 --> 02:06:33.169 align:start position:0% essentially keep updating a tree and we don't<02:06:31.440> even<02:06:31.619> need<02:06:31.860> to<02:06:31.980> post<02:06:32.159> a<02:06:32.400> lot<02:06:32.520> post<02:06:32.880> a<02:06:33.060> lot 02:06:33.169 --> 02:06:33.179 align:start position:0% don't even need to post a lot post a lot 02:06:33.179 --> 02:06:34.609 align:start position:0% don't even need to post a lot post a lot of<02:06:33.239> cool<02:06:33.360> data<02:06:33.780> because<02:06:33.840> the<02:06:34.020> cool<02:06:34.139> data<02:06:34.500> we 02:06:34.609 --> 02:06:34.619 align:start position:0% of cool data because the cool data we 02:06:34.619 --> 02:06:36.950 align:start position:0% of cool data because the cool data we passed<02:06:34.980> is<02:06:35.400> literally<02:06:35.699> just<02:06:35.940> the<02:06:36.119> proof<02:06:36.480> so 02:06:36.950 --> 02:06:36.960 align:start position:0% passed is literally just the proof so 02:06:36.960 --> 02:06:39.649 align:start position:0% passed is literally just the proof so we're<02:06:37.260> very<02:06:37.679> very<02:06:37.860> happy<02:06:38.580> but<02:06:39.060> again<02:06:39.239> I<02:06:39.540> don't 02:06:39.649 --> 02:06:39.659 align:start position:0% we're very very happy but again I don't 02:06:39.659 --> 02:06:41.629 align:start position:0% we're very very happy but again I don't want<02:06:39.780> to<02:06:39.840> say<02:06:40.020> that<02:06:40.260> all<02:06:40.500> of<02:06:40.739> the<02:06:41.099> one<02:06:41.400> of<02:06:41.460> these 02:06:41.629 --> 02:06:41.639 align:start position:0% want to say that all of the one of these 02:06:41.639 --> 02:06:43.669 align:start position:0% want to say that all of the one of these approaches<02:06:41.940> is<02:06:42.119> the<02:06:42.360> best<02:06:42.480> one<02:06:42.659> because<02:06:43.260> as 02:06:43.669 --> 02:06:43.679 align:start position:0% approaches is the best one because as 02:06:43.679 --> 02:06:45.770 align:start position:0% approaches is the best one because as you<02:06:43.860> see<02:06:43.980> there<02:06:44.340> are<02:06:44.580> trade-offs 02:06:45.770 --> 02:06:45.780 align:start position:0% you see there are trade-offs 02:06:45.780 --> 02:06:47.930 align:start position:0% you see there are trade-offs and 02:06:47.930 --> 02:06:47.940 align:start position:0% and 02:06:47.940 --> 02:06:50.750 align:start position:0% and yeah<02:06:48.420> so<02:06:49.199> this<02:06:49.500> part<02:06:49.679> is<02:06:50.040> actually<02:06:50.280> pretty 02:06:50.750 --> 02:06:50.760 align:start position:0% yeah so this part is actually pretty 02:06:50.760 --> 02:06:52.970 align:start position:0% yeah so this part is actually pretty easy<02:06:51.000> so<02:06:51.599> as<02:06:51.780> you<02:06:51.960> know<02:06:52.080> as<02:06:52.380> you<02:06:52.500> may<02:06:52.619> notice 02:06:52.970 --> 02:06:52.980 align:start position:0% easy so as you know as you may notice 02:06:52.980 --> 02:06:55.070 align:start position:0% easy so as you know as you may notice here<02:06:53.880> I<02:06:54.060> was<02:06:54.179> explaining<02:06:54.540> like<02:06:54.719> the<02:06:54.900> second 02:06:55.070 --> 02:06:55.080 align:start position:0% here I was explaining like the second 02:06:55.080 --> 02:06:57.050 align:start position:0% here I was explaining like the second step<02:06:55.440> when<02:06:55.860> it<02:06:56.219> comes<02:06:56.400> to<02:06:56.520> two<02:06:56.699> linguist 02:06:57.050 --> 02:06:57.060 align:start position:0% step when it comes to two linguist 02:06:57.060 --> 02:06:59.870 align:start position:0% step when it comes to two linguist storage<02:06:57.300> proofs<02:06:57.780> and<02:06:58.380> now<02:06:58.560> there<02:06:58.920> is<02:06:59.099> the<02:06:59.699> the 02:06:59.870 --> 02:06:59.880 align:start position:0% storage proofs and now there is the the 02:06:59.880 --> 02:07:01.370 align:start position:0% storage proofs and now there is the the last<02:07:00.060> part<02:07:00.239> which<02:07:00.420> is<02:07:00.599> essentially<02:07:00.900> verifying 02:07:01.370 --> 02:07:01.380 align:start position:0% last part which is essentially verifying 02:07:01.380 --> 02:07:04.250 align:start position:0% last part which is essentially verifying the<02:07:01.560> proof<02:07:01.739> itself<02:07:02.179> so<02:07:03.179> approach<02:07:03.780> number<02:07:04.020> one 02:07:04.250 --> 02:07:04.260 align:start position:0% the proof itself so approach number one 02:07:04.260 --> 02:07:05.990 align:start position:0% the proof itself so approach number one is<02:07:04.560> verifying<02:07:05.040> the<02:07:05.159> proof<02:07:05.400> directly<02:07:05.699> on<02:07:05.880> the 02:07:05.990 --> 02:07:06.000 align:start position:0% is verifying the proof directly on the 02:07:06.000 --> 02:07:08.149 align:start position:0% is verifying the proof directly on the Chain<02:07:06.179> approach<02:07:06.900> number<02:07:07.080> two<02:07:07.320> let's<02:07:07.739> verify 02:07:08.149 --> 02:07:08.159 align:start position:0% Chain approach number two let's verify 02:07:08.159 --> 02:07:09.350 align:start position:0% Chain approach number two let's verify the<02:07:08.280> proving<02:07:08.580> side<02:07:08.760> the<02:07:08.880> star<02:07:09.000> can<02:07:09.239> then 02:07:09.350 --> 02:07:09.360 align:start position:0% the proving side the star can then 02:07:09.360 --> 02:07:11.330 align:start position:0% the proving side the star can then verify<02:07:09.719> the<02:07:09.840> Stark<02:07:10.080> approach<02:07:10.920> number<02:07:11.040> three 02:07:11.330 --> 02:07:11.340 align:start position:0% verify the Stark approach number three 02:07:11.340 --> 02:07:13.850 align:start position:0% verify the Stark approach number three let's<02:07:11.760> verify<02:07:12.420> multiple<02:07:12.900> proofs<02:07:13.320> inside<02:07:13.560> the 02:07:13.850 --> 02:07:13.860 align:start position:0% let's verify multiple proofs inside the 02:07:13.860 --> 02:07:15.770 align:start position:0% let's verify multiple proofs inside the snark<02:07:14.159> and<02:07:14.340> then<02:07:14.460> verify<02:07:14.760> the<02:07:14.880> snark<02:07:15.239> we<02:07:15.659> can 02:07:15.770 --> 02:07:15.780 align:start position:0% snark and then verify the snark we can 02:07:15.780 --> 02:07:17.870 align:start position:0% snark and then verify the snark we can aggregate<02:07:16.199> multiple<02:07:16.500> sharks<02:07:16.920> together<02:07:17.040> and 02:07:17.870 --> 02:07:17.880 align:start position:0% aggregate multiple sharks together and 02:07:17.880 --> 02:07:19.729 align:start position:0% aggregate multiple sharks together and so<02:07:18.000> on<02:07:18.179> but<02:07:18.360> obviously<02:07:18.840> there<02:07:19.500> are<02:07:19.619> some 02:07:19.729 --> 02:07:19.739 align:start position:0% so on but obviously there are some 02:07:19.739 --> 02:07:20.990 align:start position:0% so on but obviously there are some trade-offs<02:07:20.280> especially<02:07:20.520> when<02:07:20.639> it<02:07:20.760> comes<02:07:20.880> to 02:07:20.990 --> 02:07:21.000 align:start position:0% trade-offs especially when it comes to 02:07:21.000 --> 02:07:22.550 align:start position:0% trade-offs especially when it comes to proving<02:07:21.360> time 02:07:22.550 --> 02:07:22.560 align:start position:0% proving time 02:07:22.560 --> 02:07:25.189 align:start position:0% proving time um<02:07:22.619> and<02:07:23.340> yeah<02:07:23.400> so<02:07:23.760> now<02:07:23.940> why<02:07:24.780> the<02:07:25.020> first 02:07:25.189 --> 02:07:25.199 align:start position:0% um and yeah so now why the first 02:07:25.199 --> 02:07:27.950 align:start position:0% um and yeah so now why the first approach<02:07:25.560> is<02:07:25.860> feasible<02:07:26.400> on<02:07:26.760> on<02:07:27.060> ZK<02:07:27.480> rollups 02:07:27.950 --> 02:07:27.960 align:start position:0% approach is feasible on on ZK rollups 02:07:27.960 --> 02:07:29.570 align:start position:0% approach is feasible on on ZK rollups for<02:07:28.020> example<02:07:28.260> on<02:07:28.380> structural<02:07:28.860> data<02:07:29.340> is<02:07:29.400> very 02:07:29.570 --> 02:07:29.580 align:start position:0% for example on structural data is very 02:07:29.580 --> 02:07:31.790 align:start position:0% for example on structural data is very cheap<02:07:29.820> and<02:07:30.420> what<02:07:30.599> we<02:07:30.719> want<02:07:30.900> to<02:07:31.020> avoid<02:07:31.320> in<02:07:31.560> this 02:07:31.790 --> 02:07:31.800 align:start position:0% cheap and what we want to avoid in this 02:07:31.800 --> 02:07:34.250 align:start position:0% cheap and what we want to avoid in this specific<02:07:32.099> processes<02:07:32.699> called<02:07:33.119> Data<02:07:33.599> so<02:07:34.080> this 02:07:34.250 --> 02:07:34.260 align:start position:0% specific processes called Data so this 02:07:34.260 --> 02:07:35.810 align:start position:0% specific processes called Data so this approach<02:07:34.560> is<02:07:34.679> for<02:07:34.920> example<02:07:35.099> feasible<02:07:35.580> on 02:07:35.810 --> 02:07:35.820 align:start position:0% approach is for example feasible on 02:07:35.820 --> 02:07:38.089 align:start position:0% approach is for example feasible on starknet<02:07:36.360> but<02:07:36.960> for<02:07:37.260> example<02:07:37.500> if<02:07:37.679> you<02:07:37.860> want<02:07:37.980> to 02:07:38.089 --> 02:07:38.099 align:start position:0% starknet but for example if you want to 02:07:38.099 --> 02:07:39.830 align:start position:0% starknet but for example if you want to verify<02:07:38.460> like<02:07:38.639> a<02:07:38.760> proof<02:07:39.000> on<02:07:39.119> optimism<02:07:39.480> or<02:07:39.719> a 02:07:39.830 --> 02:07:39.840 align:start position:0% verify like a proof on optimism or a 02:07:39.840 --> 02:07:41.570 align:start position:0% verify like a proof on optimism or a collate<02:07:40.080> is<02:07:40.260> very<02:07:40.380> expensive<02:07:40.800> you<02:07:41.280> want<02:07:41.460> to 02:07:41.570 --> 02:07:41.580 align:start position:0% collate is very expensive you want to 02:07:41.580 --> 02:07:43.609 align:start position:0% collate is very expensive you want to reduce<02:07:41.820> it<02:07:42.060> as<02:07:42.300> much<02:07:42.480> as<02:07:42.599> possible<02:07:42.960> so<02:07:43.440> for 02:07:43.609 --> 02:07:43.619 align:start position:0% reduce it as much as possible so for 02:07:43.619 --> 02:07:45.050 align:start position:0% reduce it as much as possible so for that<02:07:43.800> reason<02:07:43.920> you<02:07:44.219> might<02:07:44.520> want<02:07:44.699> to<02:07:44.820> use<02:07:44.940> a 02:07:45.050 --> 02:07:45.060 align:start position:0% that reason you might want to use a 02:07:45.060 --> 02:07:48.589 align:start position:0% that reason you might want to use a snark<02:07:45.360> and<02:07:46.020> finally<02:07:46.320> if<02:07:46.679> you<02:07:46.739> have<02:07:46.920> like<02:07:47.159> many 02:07:48.589 --> 02:07:48.599 align:start position:0% snark and finally if you have like many 02:07:48.599 --> 02:07:50.990 align:start position:0% snark and finally if you have like many slots<02:07:49.260> that<02:07:49.440> you<02:07:49.560> want<02:07:49.679> to<02:07:49.800> prove<02:07:50.099> why<02:07:50.699> can't 02:07:50.990 --> 02:07:51.000 align:start position:0% slots that you want to prove why can't 02:07:51.000 --> 02:07:52.790 align:start position:0% slots that you want to prove why can't you<02:07:51.179> just<02:07:51.300> verify<02:07:51.719> them<02:07:51.960> inside<02:07:52.139> one<02:07:52.440> snark 02:07:52.790 --> 02:07:52.800 align:start position:0% you just verify them inside one snark 02:07:52.800 --> 02:07:55.790 align:start position:0% you just verify them inside one snark you're<02:07:53.159> gonna<02:07:53.340> pay<02:07:53.520> improver<02:07:53.940> time<02:07:54.179> but<02:07:55.020> you 02:07:55.790 --> 02:07:55.800 align:start position:0% you're gonna pay improver time but you 02:07:55.800 --> 02:07:57.770 align:start position:0% you're gonna pay improver time but you just<02:07:55.980> present<02:07:56.219> one<02:07:56.400> proof<02:07:56.820> at<02:07:56.940> the<02:07:57.060> end<02:07:57.179> so 02:07:57.770 --> 02:07:57.780 align:start position:0% just present one proof at the end so 02:07:57.780 --> 02:08:01.669 align:start position:0% just present one proof at the end so this<02:07:58.139> approach<02:07:58.500> is<02:07:59.280> cheaper<02:08:00.060> is<02:08:00.780> the<02:08:01.080> cheapest 02:08:01.669 --> 02:08:01.679 align:start position:0% this approach is cheaper is the cheapest 02:08:01.679 --> 02:08:03.470 align:start position:0% this approach is cheaper is the cheapest one<02:08:01.800> but<02:08:02.040> only<02:08:02.219> if<02:08:02.460> you<02:08:02.580> have<02:08:02.820> multiple 02:08:03.470 --> 02:08:03.480 align:start position:0% one but only if you have multiple 02:08:03.480 --> 02:08:07.010 align:start position:0% one but only if you have multiple actions<02:08:04.020> to<02:08:04.199> to<02:08:04.440> take<02:08:04.679> so 02:08:07.010 --> 02:08:07.020 align:start position:0% actions to to take so 02:08:07.020 --> 02:08:09.649 align:start position:0% actions to to take so there<02:08:07.500> are<02:08:07.619> trade-offs 02:08:09.649 --> 02:08:09.659 align:start position:0% there are trade-offs 02:08:09.659 --> 02:08:13.089 align:start position:0% there are trade-offs so<02:08:10.440> let's<02:08:10.800> identify<02:08:11.400> them 02:08:13.089 --> 02:08:13.099 align:start position:0% so let's identify them 02:08:13.099 --> 02:08:15.649 align:start position:0% so let's identify them categories<02:08:14.099> approver<02:08:14.639> overhead<02:08:15.060> latency 02:08:15.649 --> 02:08:15.659 align:start position:0% categories approver overhead latency 02:08:15.659 --> 02:08:19.490 align:start position:0% categories approver overhead latency verification<02:08:16.380> cost<02:08:17.060> so<02:08:18.199> verifying<02:08:19.199> the<02:08:19.260> proof 02:08:19.490 --> 02:08:19.500 align:start position:0% verification cost so verifying the proof 02:08:19.500 --> 02:08:21.770 align:start position:0% verification cost so verifying the proof directly<02:08:19.860> prover<02:08:20.520> overhead<02:08:20.940> doesn't<02:08:21.420> exist 02:08:21.770 --> 02:08:21.780 align:start position:0% directly prover overhead doesn't exist 02:08:21.780 --> 02:08:23.990 align:start position:0% directly prover overhead doesn't exist latency<02:08:22.560> doesn't<02:08:23.159> exist<02:08:23.460> because<02:08:23.639> we<02:08:23.880> don't 02:08:23.990 --> 02:08:24.000 align:start position:0% latency doesn't exist because we don't 02:08:24.000 --> 02:08:25.790 align:start position:0% latency doesn't exist because we don't need<02:08:24.119> to<02:08:24.239> prove<02:08:24.480> anything<02:08:24.800> verification 02:08:25.790 --> 02:08:25.800 align:start position:0% need to prove anything verification 02:08:25.800 --> 02:08:27.709 align:start position:0% need to prove anything verification costs<02:08:26.219> well<02:08:26.340> it<02:08:26.639> is<02:08:26.699> significant 02:08:27.709 --> 02:08:27.719 align:start position:0% costs well it is significant 02:08:27.719 --> 02:08:29.870 align:start position:0% costs well it is significant because<02:08:28.320> we<02:08:28.860> need<02:08:29.040> to<02:08:29.099> post<02:08:29.219> School<02:08:29.460> data<02:08:29.760> and 02:08:29.870 --> 02:08:29.880 align:start position:0% because we need to post School data and 02:08:29.880 --> 02:08:31.189 align:start position:0% because we need to post School data and we<02:08:30.000> need<02:08:30.119> and<02:08:30.420> we<02:08:30.599> need<02:08:30.659> to<02:08:30.780> do<02:08:30.840> the<02:08:30.960> actual 02:08:31.189 --> 02:08:31.199 align:start position:0% we need and we need to do the actual 02:08:31.199 --> 02:08:32.750 align:start position:0% we need and we need to do the actual computation<02:08:31.679> so<02:08:31.980> like<02:08:32.159> going<02:08:32.400> through<02:08:32.580> the 02:08:32.750 --> 02:08:32.760 align:start position:0% computation so like going through the 02:08:32.760 --> 02:08:34.850 align:start position:0% computation so like going through the entire<02:08:33.000> path<02:08:33.300> and<02:08:33.840> each<02:08:34.020> step<02:08:34.260> in<02:08:34.440> the<02:08:34.560> path<02:08:34.739> is 02:08:34.850 --> 02:08:34.860 align:start position:0% entire path and each step in the path is 02:08:34.860 --> 02:08:38.270 align:start position:0% entire path and each step in the path is one<02:08:35.099> hashing<02:08:35.520> function<02:08:35.820> oh<02:08:36.780> and<02:08:37.139> also 02:08:38.270 --> 02:08:38.280 align:start position:0% one hashing function oh and also 02:08:38.280 --> 02:08:40.490 align:start position:0% one hashing function oh and also let<02:08:38.699> me<02:08:38.820> get<02:08:39.000> back<02:08:39.119> to<02:08:39.239> the<02:08:39.360> previous<02:08:39.540> slide<02:08:39.900> I 02:08:40.490 --> 02:08:40.500 align:start position:0% let me get back to the previous slide I 02:08:40.500 --> 02:08:43.070 align:start position:0% let me get back to the previous slide I forgot<02:08:40.739> this<02:08:41.040> is<02:08:41.159> very<02:08:41.340> important<02:08:41.699> why 02:08:43.070 --> 02:08:43.080 align:start position:0% forgot this is very important why 02:08:43.080 --> 02:08:45.350 align:start position:0% forgot this is very important why wrapping<02:08:43.800> inside<02:08:44.099> this<02:08:44.460> wrapping<02:08:45.179> inside 02:08:45.350 --> 02:08:45.360 align:start position:0% wrapping inside this wrapping inside 02:08:45.360 --> 02:08:47.330 align:start position:0% wrapping inside this wrapping inside this<02:08:45.659> Arc<02:08:45.960> is<02:08:46.020> pretty<02:08:46.199> important<02:08:46.619> if<02:08:47.219> you're 02:08:47.330 --> 02:08:47.340 align:start position:0% this Arc is pretty important if you're 02:08:47.340 --> 02:08:50.030 align:start position:0% this Arc is pretty important if you're like<02:08:47.580> dealing<02:08:47.940> with<02:08:48.119> a<02:08:48.239> storage<02:08:48.739> layout<02:08:49.739> that 02:08:50.030 --> 02:08:50.040 align:start position:0% like dealing with a storage layout that 02:08:50.040 --> 02:08:51.950 align:start position:0% like dealing with a storage layout that is<02:08:50.219> using<02:08:50.699> a<02:08:50.880> specific<02:08:51.119> hashing<02:08:51.599> function 02:08:51.950 --> 02:08:51.960 align:start position:0% is using a specific hashing function 02:08:51.960 --> 02:08:55.370 align:start position:0% is using a specific hashing function let's<02:08:52.619> say<02:08:52.800> for<02:08:53.099> example<02:08:53.480> Peterson<02:08:54.480> Peterson 02:08:55.370 --> 02:08:55.380 align:start position:0% let's say for example Peterson Peterson 02:08:55.380 --> 02:08:58.129 align:start position:0% let's say for example Peterson Peterson is<02:08:55.739> not<02:08:55.920> available<02:08:56.040> like<02:08:56.580> on<02:08:56.760> on<02:08:57.000> the<02:08:57.420> evm<02:08:57.840> like 02:08:58.129 --> 02:08:58.139 align:start position:0% is not available like on on the evm like 02:08:58.139 --> 02:08:59.810 align:start position:0% is not available like on on the evm like you<02:08:58.500> just<02:08:58.739> need<02:08:58.920> to<02:08:59.040> implement<02:08:59.280> it's<02:08:59.520> not<02:08:59.699> the 02:08:59.810 --> 02:08:59.820 align:start position:0% you just need to implement it's not the 02:08:59.820 --> 02:09:02.270 align:start position:0% you just need to implement it's not the pre-composed<02:09:00.360> it's<02:09:00.719> gonna<02:09:00.840> be<02:09:01.080> costly<02:09:01.440> but<02:09:02.040> if 02:09:02.270 --> 02:09:02.280 align:start position:0% pre-composed it's gonna be costly but if 02:09:02.280 --> 02:09:04.010 align:start position:0% pre-composed it's gonna be costly but if you<02:09:02.400> do<02:09:02.520> inside<02:09:02.699> the<02:09:03.000> snork<02:09:03.239> and<02:09:03.420> Peterson<02:09:03.780> is 02:09:04.010 --> 02:09:04.020 align:start position:0% you do inside the snork and Peterson is 02:09:04.020 --> 02:09:05.930 align:start position:0% you do inside the snork and Peterson is pretty<02:09:04.139> smart<02:09:04.440> friendly<02:09:04.920> it's<02:09:05.340> not<02:09:05.580> friendly 02:09:05.930 --> 02:09:05.940 align:start position:0% pretty smart friendly it's not friendly 02:09:05.940 --> 02:09:08.030 align:start position:0% pretty smart friendly it's not friendly then<02:09:06.360> well<02:09:06.780> it<02:09:07.020> just<02:09:07.260> verifies<02:09:07.739> in<02:09:07.920> our 02:09:08.030 --> 02:09:08.040 align:start position:0% then well it just verifies in our 02:09:08.040 --> 02:09:09.350 align:start position:0% then well it just verifies in our control<02:09:08.219> one<02:09:08.460> and<02:09:08.580> you<02:09:08.699> abstract<02:09:09.000> it<02:09:09.119> so<02:09:09.239> it's 02:09:09.350 --> 02:09:09.360 align:start position:0% control one and you abstract it so it's 02:09:09.360 --> 02:09:11.629 align:start position:0% control one and you abstract it so it's going<02:09:09.540> to<02:09:09.659> be<02:09:09.780> way<02:09:10.320> way<02:09:10.380> way<02:09:10.560> cheaper<02:09:11.219> but 02:09:11.629 --> 02:09:11.639 align:start position:0% going to be way way way cheaper but 02:09:11.639 --> 02:09:13.970 align:start position:0% going to be way way way cheaper but again<02:09:11.820> there<02:09:12.480> are<02:09:12.659> trade-offs<02:09:13.199> let<02:09:13.739> me<02:09:13.860> get 02:09:13.970 --> 02:09:13.980 align:start position:0% again there are trade-offs let me get 02:09:13.980 --> 02:09:16.070 align:start position:0% again there are trade-offs let me get back<02:09:14.159> to<02:09:14.280> this<02:09:14.460> so<02:09:15.239> I<02:09:15.480> went<02:09:15.599> for<02:09:15.780> this<02:09:15.960> the 02:09:16.070 --> 02:09:16.080 align:start position:0% back to this so I went for this the 02:09:16.080 --> 02:09:17.750 align:start position:0% back to this so I went for this the normal<02:09:16.260> competition<02:09:16.679> 3<02:09:16.980> star<02:09:17.280> Cricket<02:09:17.580> fight 02:09:17.750 --> 02:09:17.760 align:start position:0% normal competition 3 star Cricket fight 02:09:17.760 --> 02:09:21.410 align:start position:0% normal competition 3 star Cricket fight proof<02:09:18.119> through<02:09:18.540> the<02:09:18.719> overhead<02:09:19.080> it<02:09:19.980> exists<02:09:20.460> so 02:09:21.410 --> 02:09:21.420 align:start position:0% proof through the overhead it exists so 02:09:21.420 --> 02:09:25.250 align:start position:0% proof through the overhead it exists so we<02:09:21.840> are<02:09:22.020> not<02:09:22.320> super<02:09:23.040> happy<02:09:23.480> latency<02:09:24.480> you're 02:09:25.250 --> 02:09:25.260 align:start position:0% we are not super happy latency you're 02:09:25.260 --> 02:09:26.750 align:start position:0% we are not super happy latency you're also<02:09:25.500> not<02:09:25.619> happy<02:09:25.800> because<02:09:26.040> we<02:09:26.340> actually<02:09:26.460> need 02:09:26.750 --> 02:09:26.760 align:start position:0% also not happy because we actually need 02:09:26.760 --> 02:09:28.490 align:start position:0% also not happy because we actually need to<02:09:26.880> spend<02:09:27.119> time<02:09:27.360> on<02:09:27.540> improving<02:09:28.080> this<02:09:28.260> this 02:09:28.490 --> 02:09:28.500 align:start position:0% to spend time on improving this this 02:09:28.500 --> 02:09:31.430 align:start position:0% to spend time on improving this this thing<02:09:29.119> verification<02:09:30.119> costs<02:09:30.659> we<02:09:31.139> are<02:09:31.260> happy 02:09:31.430 --> 02:09:31.440 align:start position:0% thing verification costs we are happy 02:09:31.440 --> 02:09:33.410 align:start position:0% thing verification costs we are happy because<02:09:31.739> well<02:09:32.099> we<02:09:32.460> we<02:09:32.760> just<02:09:33.000> verify<02:09:33.300> your 02:09:33.410 --> 02:09:33.420 align:start position:0% because well we we just verify your 02:09:33.420 --> 02:09:36.050 align:start position:0% because well we we just verify your proof<02:09:33.719> so<02:09:33.900> it's<02:09:34.020> fine<02:09:34.199> and<02:09:35.040> it's<02:09:35.340> an<02:09:35.520> artifying 02:09:36.050 --> 02:09:36.060 align:start position:0% proof so it's fine and it's an artifying 02:09:36.060 --> 02:09:38.149 align:start position:0% proof so it's fine and it's an artifying multiple<02:09:36.360> proofs<02:09:36.780> the<02:09:37.139> prover<02:09:37.440> overhead<02:09:37.920> is 02:09:38.149 --> 02:09:38.159 align:start position:0% multiple proofs the prover overhead is 02:09:38.159 --> 02:09:40.310 align:start position:0% multiple proofs the prover overhead is still<02:09:38.340> there<02:09:38.580> latency<02:09:39.300> is<02:09:39.719> still<02:09:39.900> there<02:09:40.080> it's 02:09:40.310 --> 02:09:40.320 align:start position:0% still there latency is still there it's 02:09:40.320 --> 02:09:41.750 align:start position:0% still there latency is still there it's even<02:09:40.560> bigger<02:09:40.860> because<02:09:41.040> it<02:09:41.340> takes<02:09:41.460> a<02:09:41.699> bit 02:09:41.750 --> 02:09:41.760 align:start position:0% even bigger because it takes a bit 02:09:41.760 --> 02:09:43.910 align:start position:0% even bigger because it takes a bit longer<02:09:42.179> in<02:09:42.599> improving<02:09:43.020> time<02:09:43.560> and 02:09:43.910 --> 02:09:43.920 align:start position:0% longer in improving time and 02:09:43.920 --> 02:09:45.410 align:start position:0% longer in improving time and verification<02:09:44.400> because<02:09:44.639> we<02:09:44.940> are<02:09:45.060> super<02:09:45.179> happy 02:09:45.410 --> 02:09:45.420 align:start position:0% verification because we are super happy 02:09:45.420 --> 02:09:47.810 align:start position:0% verification because we are super happy because<02:09:45.719> essentially<02:09:46.139> we<02:09:46.440> can<02:09:46.639> mutualize<02:09:47.639> the 02:09:47.810 --> 02:09:47.820 align:start position:0% because essentially we can mutualize the 02:09:47.820 --> 02:09:50.810 align:start position:0% because essentially we can mutualize the cost<02:09:48.000> of<02:09:48.179> verifying<02:09:48.719> multiple<02:09:49.080> proofs 02:09:50.810 --> 02:09:50.820 align:start position:0% cost of verifying multiple proofs 02:09:50.820 --> 02:09:56.570 align:start position:0% cost of verifying multiple proofs by<02:09:51.239> just<02:09:51.420> verifying<02:09:51.960> one<02:09:52.320> single<02:09:52.679> Stark<02:09:53.099> proof 02:09:56.570 --> 02:09:56.580 align:start position:0% 02:09:56.580 --> 02:09:59.589 align:start position:0% okay<02:09:57.260> went<02:09:58.260> through<02:09:58.500> quite<02:09:58.980> a<02:09:59.099> lot<02:09:59.219> of<02:09:59.340> things 02:09:59.589 --> 02:09:59.599 align:start position:0% okay went through quite a lot of things 02:09:59.599 --> 02:10:02.810 align:start position:0% okay went through quite a lot of things let's<02:10:00.599> put<02:10:01.080> this<02:10:01.260> all<02:10:01.440> together 02:10:02.810 --> 02:10:02.820 align:start position:0% let's put this all together 02:10:02.820 --> 02:10:04.609 align:start position:0% let's put this all together so<02:10:03.179> let's<02:10:03.300> imagine<02:10:03.540> we<02:10:03.840> have<02:10:03.960> three<02:10:04.139> chains 02:10:04.609 --> 02:10:04.619 align:start position:0% so let's imagine we have three chains 02:10:04.619 --> 02:10:06.470 align:start position:0% so let's imagine we have three chains and<02:10:05.099> we<02:10:05.340> want<02:10:05.400> to<02:10:05.520> have<02:10:05.699> interoperability 02:10:06.470 --> 02:10:06.480 align:start position:0% and we want to have interoperability 02:10:06.480 --> 02:10:09.109 align:start position:0% and we want to have interoperability interoperability<02:10:07.380> between<02:10:07.739> them<02:10:08.040> so<02:10:08.760> we<02:10:09.000> have 02:10:09.109 --> 02:10:09.119 align:start position:0% interoperability between them so we have 02:10:09.119 --> 02:10:11.930 align:start position:0% interoperability between them so we have chain<02:10:09.360> Z<02:10:09.599> chain<02:10:09.900> X<02:10:10.080> and<02:10:10.260> chain<02:10:10.380> y 02:10:11.930 --> 02:10:11.940 align:start position:0% chain Z chain X and chain y 02:10:11.940 --> 02:10:14.570 align:start position:0% chain Z chain X and chain y so<02:10:12.239> it<02:10:12.719> all<02:10:12.840> starts<02:10:13.199> with<02:10:13.320> a<02:10:13.560> message<02:10:13.679> AKA 02:10:14.570 --> 02:10:14.580 align:start position:0% so it all starts with a message AKA 02:10:14.580 --> 02:10:16.729 align:start position:0% so it all starts with a message AKA commitment<02:10:15.179> we<02:10:15.659> send<02:10:15.840> a<02:10:16.020> message<02:10:16.139> in<02:10:16.440> order<02:10:16.560> to 02:10:16.729 --> 02:10:16.739 align:start position:0% commitment we send a message in order to 02:10:16.739 --> 02:10:19.010 align:start position:0% commitment we send a message in order to get<02:10:17.099> the<02:10:17.280> commitment<02:10:17.639> so<02:10:18.060> let's<02:10:18.480> say<02:10:18.659> that<02:10:18.840> we 02:10:19.010 --> 02:10:19.020 align:start position:0% get the commitment so let's say that we 02:10:19.020 --> 02:10:22.030 align:start position:0% get the commitment so let's say that we send<02:10:19.199> a<02:10:19.380> message<02:10:19.500> from<02:10:19.860> chain<02:10:20.280> Z<02:10:20.639> to<02:10:21.360> chain<02:10:21.659> X 02:10:22.030 --> 02:10:22.040 align:start position:0% send a message from chain Z to chain X 02:10:22.040 --> 02:10:25.129 align:start position:0% send a message from chain Z to chain X because<02:10:23.040> on<02:10:23.340> chain<02:10:23.520> X<02:10:23.760> we<02:10:24.000> want<02:10:24.179> to<02:10:24.300> access<02:10:24.540> the 02:10:25.129 --> 02:10:25.139 align:start position:0% because on chain X we want to access the 02:10:25.139 --> 02:10:28.370 align:start position:0% because on chain X we want to access the the<02:10:25.560> state<02:10:25.800> of<02:10:26.040> changing<02:10:26.820> so<02:10:27.719> what<02:10:27.900> do<02:10:28.080> we<02:10:28.199> do 02:10:28.370 --> 02:10:28.380 align:start position:0% the state of changing so what do we do 02:10:28.380 --> 02:10:30.050 align:start position:0% the state of changing so what do we do once<02:10:28.739> we<02:10:28.800> have<02:10:28.860> the<02:10:28.980> commitment<02:10:29.340> we<02:10:29.699> literally 02:10:30.050 --> 02:10:30.060 align:start position:0% once we have the commitment we literally 02:10:30.060 --> 02:10:32.209 align:start position:0% once we have the commitment we literally recreate<02:10:30.659> all<02:10:30.840> the<02:10:30.960> headers 02:10:32.209 --> 02:10:32.219 align:start position:0% recreate all the headers 02:10:32.219 --> 02:10:35.089 align:start position:0% recreate all the headers using<02:10:33.000> one<02:10:33.179> of<02:10:33.300> the<02:10:33.360> three<02:10:33.480> approaches 02:10:35.089 --> 02:10:35.099 align:start position:0% using one of the three approaches 02:10:35.099 --> 02:10:37.250 align:start position:0% using one of the three approaches and<02:10:35.639> once<02:10:35.940> we<02:10:36.000> recreate<02:10:36.480> it<02:10:36.540> the<02:10:36.840> header<02:10:37.139> is 02:10:37.250 --> 02:10:37.260 align:start position:0% and once we recreate it the header is 02:10:37.260 --> 02:10:38.870 align:start position:0% and once we recreate it the header is still<02:10:37.380> the<02:10:37.500> point<02:10:37.679> for<02:10:38.280> which<02:10:38.400> I<02:10:38.639> want<02:10:38.760> to 02:10:38.870 --> 02:10:38.880 align:start position:0% still the point for which I want to 02:10:38.880 --> 02:10:41.089 align:start position:0% still the point for which I want to prove<02:10:39.239> the<02:10:39.360> storage<02:10:39.540> I<02:10:40.199> just<02:10:40.380> verify<02:10:40.739> a<02:10:40.860> proof 02:10:41.089 --> 02:10:41.099 align:start position:0% prove the storage I just verify a proof 02:10:41.099 --> 02:10:42.589 align:start position:0% prove the storage I just verify a proof and<02:10:41.219> again<02:10:41.340> for<02:10:41.520> verifying<02:10:42.000> get<02:10:42.119> proof<02:10:42.360> there 02:10:42.589 --> 02:10:42.599 align:start position:0% and again for verifying get proof there 02:10:42.599 --> 02:10:44.149 align:start position:0% and again for verifying get proof there are<02:10:42.780> multiple<02:10:43.080> approaches<02:10:43.560> but<02:10:43.739> now<02:10:43.920> let's 02:10:44.149 --> 02:10:44.159 align:start position:0% are multiple approaches but now let's 02:10:44.159 --> 02:10:46.609 align:start position:0% are multiple approaches but now let's say<02:10:44.400> that<02:10:44.520> on<02:10:44.699> chain<02:10:44.880> y<02:10:45.179> I<02:10:45.960> want<02:10:46.020> to<02:10:46.139> access<02:10:46.320> the 02:10:46.609 --> 02:10:46.619 align:start position:0% say that on chain y I want to access the 02:10:46.619 --> 02:10:49.010 align:start position:0% say that on chain y I want to access the state<02:10:46.739> of<02:10:46.920> change<02:10:47.099> Z<02:10:47.400> and<02:10:48.239> there<02:10:48.540> is<02:10:48.719> no<02:10:48.840> direct 02:10:49.010 --> 02:10:49.020 align:start position:0% state of change Z and there is no direct 02:10:49.020 --> 02:10:51.470 align:start position:0% state of change Z and there is no direct communication<02:10:49.679> between<02:10:50.040> chain<02:10:50.400> Y<02:10:51.060> and<02:10:51.300> chain 02:10:51.470 --> 02:10:51.480 align:start position:0% communication between chain Y and chain 02:10:51.480 --> 02:10:55.010 align:start position:0% communication between chain Y and chain Z<02:10:51.780> so<02:10:52.320> it<02:10:52.739> must<02:10:52.860> be<02:10:52.980> routed<02:10:53.340> through<02:10:53.520> trainx<02:10:54.659> by 02:10:55.010 --> 02:10:55.020 align:start position:0% Z so it must be routed through trainx by 02:10:55.020 --> 02:10:56.149 align:start position:0% Z so it must be routed through trainx by the<02:10:55.199> way<02:10:55.199> I'm 02:10:56.149 --> 02:10:56.159 align:start position:0% the way I'm 02:10:56.159 --> 02:10:58.609 align:start position:0% the way I'm like<02:10:56.820> talking<02:10:57.179> about<02:10:58.020> this<02:10:58.199> in<02:10:58.380> a<02:10:58.500> pretty 02:10:58.609 --> 02:10:58.619 align:start position:0% like talking about this in a pretty 02:10:58.619 --> 02:11:00.770 align:start position:0% like talking about this in a pretty abstract<02:10:58.920> Way<02:10:59.099> by<02:10:59.340> Chain<02:10:59.699> X<02:10:59.940> I<02:11:00.119> just<02:11:00.239> mini<02:11:00.420> room 02:11:00.770 --> 02:11:00.780 align:start position:0% abstract Way by Chain X I just mini room 02:11:00.780 --> 02:11:02.750 align:start position:0% abstract Way by Chain X I just mini room later<02:11:01.020> one 02:11:02.750 --> 02:11:02.760 align:start position:0% later one 02:11:02.760 --> 02:11:05.030 align:start position:0% later one um<02:11:02.880> yeah<02:11:03.119> so<02:11:03.480> from<02:11:04.020> chain<02:11:04.199> X<02:11:04.500> I'm<02:11:04.739> just<02:11:04.920> gonna 02:11:05.030 --> 02:11:05.040 align:start position:0% um yeah so from chain X I'm just gonna 02:11:05.040 --> 02:11:06.709 align:start position:0% um yeah so from chain X I'm just gonna send<02:11:05.340> again<02:11:05.580> the<02:11:05.820> commitment<02:11:06.179> about<02:11:06.420> change 02:11:06.709 --> 02:11:06.719 align:start position:0% send again the commitment about change 02:11:06.719 --> 02:11:08.990 align:start position:0% send again the commitment about change the<02:11:07.080> as<02:11:07.380> a<02:11:07.560> message<02:11:07.739> and<02:11:08.460> then<02:11:08.639> simply 02:11:08.990 --> 02:11:09.000 align:start position:0% the as a message and then simply 02:11:09.000 --> 02:11:11.629 align:start position:0% the as a message and then simply recreate<02:11:09.540> all<02:11:09.840> these<02:11:10.139> all<02:11:10.440> these<02:11:10.739> headers<02:11:11.099> as 02:11:11.629 --> 02:11:11.639 align:start position:0% recreate all these all these headers as 02:11:11.639 --> 02:11:14.209 align:start position:0% recreate all these all these headers as you<02:11:11.820> may<02:11:12.000> not<02:11:12.239> notice<02:11:13.020> it's<02:11:13.440> pretty<02:11:13.679> redundant 02:11:14.209 --> 02:11:14.219 align:start position:0% you may not notice it's pretty redundant 02:11:14.219 --> 02:11:16.189 align:start position:0% you may not notice it's pretty redundant because<02:11:14.460> we<02:11:14.880> perform<02:11:15.179> the<02:11:15.540> same<02:11:15.659> computation 02:11:16.189 --> 02:11:16.199 align:start position:0% because we perform the same computation 02:11:16.199 --> 02:11:19.729 align:start position:0% because we perform the same computation on<02:11:16.739> two<02:11:17.099> different<02:11:17.280> chains<02:11:17.960> and<02:11:18.960> we<02:11:19.619> don't 02:11:19.729 --> 02:11:19.739 align:start position:0% on two different chains and we don't 02:11:19.739 --> 02:11:21.169 align:start position:0% on two different chains and we don't need<02:11:19.920> to<02:11:20.040> do<02:11:20.159> that<02:11:20.280> especially<02:11:20.699> if<02:11:20.880> you<02:11:21.060> use 02:11:21.169 --> 02:11:21.179 align:start position:0% need to do that especially if you use 02:11:21.179 --> 02:11:22.850 align:start position:0% need to do that especially if you use like<02:11:21.360> the<02:11:21.599> third<02:11:21.960> approach<02:11:22.500> which<02:11:22.739> is 02:11:22.850 --> 02:11:22.860 align:start position:0% like the third approach which is 02:11:22.860 --> 02:11:25.850 align:start position:0% like the third approach which is generating<02:11:23.460> the<02:11:23.699> proof<02:11:24.000> on<02:11:24.179> chain<02:11:24.679> but<02:11:25.679> now 02:11:25.850 --> 02:11:25.860 align:start position:0% generating the proof on chain but now 02:11:25.860 --> 02:11:27.950 align:start position:0% generating the proof on chain but now there<02:11:26.159> is<02:11:26.280> another<02:11:26.400> problem<02:11:26.880> how<02:11:27.659> do<02:11:27.780> you 02:11:27.950 --> 02:11:27.960 align:start position:0% there is another problem how do you 02:11:27.960 --> 02:11:29.570 align:start position:0% there is another problem how do you actually<02:11:28.080> know<02:11:28.320> what<02:11:28.560> you<02:11:28.739> should<02:11:28.860> do<02:11:29.099> like 02:11:29.570 --> 02:11:29.580 align:start position:0% actually know what you should do like 02:11:29.580 --> 02:11:31.550 align:start position:0% actually know what you should do like you<02:11:29.760> need<02:11:29.940> to<02:11:30.060> be<02:11:30.239> somehow<02:11:30.599> aware<02:11:30.960> of<02:11:31.080> what<02:11:31.380> is 02:11:31.550 --> 02:11:31.560 align:start position:0% you need to be somehow aware of what is 02:11:31.560 --> 02:11:34.129 align:start position:0% you need to be somehow aware of what is happening<02:11:31.920> and<02:11:32.520> for<02:11:32.699> that<02:11:32.820> reason<02:11:33.139> we 02:11:34.129 --> 02:11:34.139 align:start position:0% happening and for that reason we 02:11:34.139 --> 02:11:36.770 align:start position:0% happening and for that reason we introduce<02:11:34.560> an<02:11:34.980> API<02:11:35.400> we<02:11:36.000> don't<02:11:36.179> expect<02:11:36.360> like 02:11:36.770 --> 02:11:36.780 align:start position:0% introduce an API we don't expect like 02:11:36.780 --> 02:11:38.689 align:start position:0% introduce an API we don't expect like developers<02:11:37.560> to<02:11:37.860> deal<02:11:38.159> with<02:11:38.400> all<02:11:38.580> that 02:11:38.689 --> 02:11:38.699 align:start position:0% developers to deal with all that 02:11:38.699 --> 02:11:40.910 align:start position:0% developers to deal with all that complexities<02:11:39.300> choosing<02:11:40.260> the<02:11:40.440> right<02:11:40.560> approach 02:11:40.910 --> 02:11:40.920 align:start position:0% complexities choosing the right approach 02:11:40.920 --> 02:11:43.729 align:start position:0% complexities choosing the right approach for<02:11:41.219> the<02:11:41.460> direct<02:11:41.940> thing<02:11:42.239> essentially<02:11:43.139> right 02:11:43.729 --> 02:11:43.739 align:start position:0% for the direct thing essentially right 02:11:43.739 --> 02:11:48.050 align:start position:0% for the direct thing essentially right now<02:11:43.860> our<02:11:44.099> apis<02:11:45.139> optimizes<02:11:46.139> cost<02:11:46.500> wise<02:11:47.060> soon 02:11:48.050 --> 02:11:48.060 align:start position:0% now our apis optimizes cost wise soon 02:11:48.060 --> 02:11:50.990 align:start position:0% now our apis optimizes cost wise soon we'll<02:11:48.300> be<02:11:48.480> able<02:11:48.659> to<02:11:48.780> optimize<02:11:49.260> latency<02:11:49.679> wise 02:11:50.990 --> 02:11:51.000 align:start position:0% we'll be able to optimize latency wise 02:11:51.000 --> 02:11:53.689 align:start position:0% we'll be able to optimize latency wise um<02:11:51.060> and<02:11:51.900> yeah<02:11:52.020> and<02:11:52.500> essentially 02:11:53.689 --> 02:11:53.699 align:start position:0% um and yeah and essentially 02:11:53.699 --> 02:11:55.189 align:start position:0% um and yeah and essentially that's<02:11:54.239> it 02:11:55.189 --> 02:11:55.199 align:start position:0% that's it 02:11:55.199 --> 02:11:58.490 align:start position:0% that's it um<02:11:55.260> just<02:11:56.040> about<02:11:56.280> our<02:11:56.580> API<02:11:57.060> I<02:11:57.780> highly<02:11:58.080> highly 02:11:58.490 --> 02:11:58.500 align:start position:0% um just about our API I highly highly 02:11:58.500 --> 02:12:01.609 align:start position:0% um just about our API I highly highly encourage<02:11:58.920> you<02:11:59.099> to<02:11:59.639> check<02:12:00.119> this<02:12:00.300> out 02:12:01.609 --> 02:12:01.619 align:start position:0% encourage you to check this out 02:12:01.619 --> 02:12:03.649 align:start position:0% encourage you to check this out um<02:12:01.739> and<02:12:02.219> yeah<02:12:02.340> like<02:12:02.639> a<02:12:02.820> few<02:12:03.000> final<02:12:03.119> words<02:12:03.480> about 02:12:03.649 --> 02:12:03.659 align:start position:0% um and yeah like a few final words about 02:12:03.659 --> 02:12:06.229 align:start position:0% um and yeah like a few final words about the<02:12:03.900> API<02:12:04.199> it<02:12:04.739> acts<02:12:04.980> as<02:12:05.040> a<02:12:05.219> coordinator<02:12:05.639> it 02:12:06.229 --> 02:12:06.239 align:start position:0% the API it acts as a coordinator it 02:12:06.239 --> 02:12:08.510 align:start position:0% the API it acts as a coordinator it optimize<02:12:06.719> the<02:12:06.900> costs<02:12:07.199> it<02:12:07.619> optimizes<02:12:08.099> the<02:12:08.340> cost 02:12:08.510 --> 02:12:08.520 align:start position:0% optimize the costs it optimizes the cost 02:12:08.520 --> 02:12:11.209 align:start position:0% optimize the costs it optimizes the cost because<02:12:08.760> we<02:12:09.179> can<02:12:09.300> batch<02:12:09.540> multiple<02:12:09.900> things<02:12:10.219> and 02:12:11.209 --> 02:12:11.219 align:start position:0% because we can batch multiple things and 02:12:11.219 --> 02:12:13.609 align:start position:0% because we can batch multiple things and once<02:12:11.639> the<02:12:11.760> job<02:12:11.940> is<02:12:12.119> done<02:12:12.300> we<02:12:13.080> get<02:12:13.500> a 02:12:13.609 --> 02:12:13.619 align:start position:0% once the job is done we get a 02:12:13.619 --> 02:12:16.370 align:start position:0% once the job is done we get a notification<02:12:14.040> like<02:12:14.280> via<02:12:14.639> webhook<02:12:15.300> VIA<02:12:16.260> an 02:12:16.370 --> 02:12:16.380 align:start position:0% notification like via webhook VIA an 02:12:16.380 --> 02:12:17.930 align:start position:0% notification like via webhook VIA an event<02:12:16.500> like<02:12:16.739> whatever<02:12:16.920> you<02:12:17.340> want<02:12:17.460> so 02:12:17.930 --> 02:12:17.940 align:start position:0% event like whatever you want so 02:12:17.940 --> 02:12:20.149 align:start position:0% event like whatever you want so essentially<02:12:18.300> you're<02:12:19.199> not<02:12:19.380> you<02:12:19.800> don't<02:12:19.920> need<02:12:20.099> to 02:12:20.149 --> 02:12:20.159 align:start position:0% essentially you're not you don't need to 02:12:20.159 --> 02:12:23.209 align:start position:0% essentially you're not you don't need to be<02:12:20.400> like<02:12:20.940> a<02:12:21.179> infrastructure<02:12:21.900> maintainer<02:12:22.619> and 02:12:23.209 --> 02:12:23.219 align:start position:0% be like a infrastructure maintainer and 02:12:23.219 --> 02:12:24.470 align:start position:0% be like a infrastructure maintainer and you<02:12:23.400> can<02:12:23.520> just<02:12:23.639> focus<02:12:23.940> on<02:12:24.119> essentially 02:12:24.470 --> 02:12:24.480 align:start position:0% you can just focus on essentially 02:12:24.480 --> 02:12:26.750 align:start position:0% you can just focus on essentially building<02:12:24.840> on<02:12:25.199> top<02:12:25.380> of<02:12:25.560> this<02:12:25.679> primitive 02:12:26.750 --> 02:12:26.760 align:start position:0% building on top of this primitive 02:12:26.760 --> 02:12:28.609 align:start position:0% building on top of this primitive and<02:12:27.239> I<02:12:27.360> think<02:12:27.540> that's<02:12:27.719> it 02:12:28.609 --> 02:12:28.619 align:start position:0% and I think that's it 02:12:28.619 --> 02:12:43.430 align:start position:0% and I think that's it um<02:12:28.679> questions 02:12:43.430 --> 02:12:43.440 align:start position:0% 02:12:43.440 --> 02:12:46.609 align:start position:0% so<02:12:44.340> the<02:12:44.699> API<02:12:45.119> essentially<02:12:45.540> is<02:12:45.659> a<02:12:45.840> rest<02:12:46.020> API<02:12:46.440> for 02:12:46.609 --> 02:12:46.619 align:start position:0% so the API essentially is a rest API for 02:12:46.619 --> 02:12:49.129 align:start position:0% so the API essentially is a rest API for now<02:12:46.800> we<02:12:47.340> also<02:12:47.580> have<02:12:47.699> a<02:12:47.820> Json<02:12:48.060> interface<02:12:48.599> we 02:12:49.129 --> 02:12:49.139 align:start position:0% now we also have a Json interface we 02:12:49.139 --> 02:12:52.189 align:start position:0% now we also have a Json interface we have<02:12:49.320> option<02:12:49.920> function<02:12:50.520> entry<02:12:50.880> points<02:12:51.239> so<02:12:51.780> we 02:12:52.189 --> 02:12:52.199 align:start position:0% have option function entry points so we 02:12:52.199 --> 02:12:54.169 align:start position:0% have option function entry points so we can<02:12:52.320> request<02:12:52.619> the<02:12:52.860> data<02:12:53.219> like<02:12:53.760> by<02:12:54.000> making 02:12:54.169 --> 02:12:54.179 align:start position:0% can request the data like by making 02:12:54.179 --> 02:12:56.689 align:start position:0% can request the data like by making enough<02:12:54.360> jingle<02:12:54.840> like<02:12:55.199> calling<02:12:55.920> a<02:12:55.980> rest<02:12:56.099> API<02:12:56.579> or 02:12:56.689 --> 02:12:56.699 align:start position:0% enough jingle like calling a rest API or 02:12:56.699 --> 02:13:00.229 align:start position:0% enough jingle like calling a rest API or like<02:12:56.880> calling<02:12:57.179> a<02:12:57.300> Json<02:12:57.960> or<02:12:58.139> PC<02:12:58.380> method<02:12:59.000> or<02:13:00.000> if 02:13:00.229 --> 02:13:00.239 align:start position:0% like calling a Json or PC method or if 02:13:00.239 --> 02:13:01.609 align:start position:0% like calling a Json or PC method or if you're<02:13:00.360> a<02:13:00.540> smart<02:13:00.599> contracts<02:13:01.079> like<02:13:01.260> wants<02:13:01.560> to 02:13:01.609 --> 02:13:01.619 align:start position:0% you're a smart contracts like wants to 02:13:01.619 --> 02:13:03.410 align:start position:0% you're a smart contracts like wants to access<02:13:01.800> this<02:13:02.040> data<02:13:02.400> then<02:13:02.520> you<02:13:02.880> just<02:13:03.000> submit<02:13:03.300> an 02:13:03.410 --> 02:13:03.420 align:start position:0% access this data then you just submit an 02:13:03.420 --> 02:13:05.330 align:start position:0% access this data then you just submit an event<02:13:03.599> we're<02:13:03.840> gonna<02:13:03.960> catch<02:13:04.320> the<02:13:04.380> event<02:13:04.560> and 02:13:05.330 --> 02:13:05.340 align:start position:0% event we're gonna catch the event and 02:13:05.340 --> 02:13:08.089 align:start position:0% event we're gonna catch the event and later<02:13:05.579> on<02:13:05.820> like<02:13:06.060> after<02:13:06.780> a<02:13:07.020> bit<02:13:07.139> of<02:13:07.320> time<02:13:07.440> fit 02:13:08.089 --> 02:13:08.099 align:start position:0% later on like after a bit of time fit 02:13:08.099 --> 02:13:10.069 align:start position:0% later on like after a bit of time fit this<02:13:08.520> uh<02:13:08.940> the<02:13:09.179> specific<02:13:09.360> data<02:13:09.719> inside<02:13:09.900> the 02:13:10.069 --> 02:13:10.079 align:start position:0% this uh the specific data inside the 02:13:10.079 --> 02:13:11.810 align:start position:0% this uh the specific data inside the smart<02:13:10.260> contract<02:13:10.679> so<02:13:11.159> we<02:13:11.280> have<02:13:11.460> like<02:13:11.579> a<02:13:11.699> bunch 02:13:11.810 --> 02:13:11.820 align:start position:0% smart contract so we have like a bunch 02:13:11.820 --> 02:13:14.030 align:start position:0% smart contract so we have like a bunch of<02:13:11.940> interfaces<02:13:12.599> and<02:13:13.320> by<02:13:13.380> the<02:13:13.500> way<02:13:13.560> speaking<02:13:13.980> of 02:13:14.030 --> 02:13:14.040 align:start position:0% of interfaces and by the way speaking of 02:13:14.040 --> 02:13:15.830 align:start position:0% of interfaces and by the way speaking of like<02:13:14.219> the<02:13:14.340> off-train<02:13:14.760> entry<02:13:15.000> points<02:13:15.300> once<02:13:15.719> the 02:13:15.830 --> 02:13:15.840 align:start position:0% like the off-train entry points once the 02:13:15.840 --> 02:13:18.050 align:start position:0% like the off-train entry points once the entire<02:13:16.199> leg<02:13:16.380> work<02:13:16.619> is<02:13:16.800> done<02:13:16.920> on<02:13:17.099> our<02:13:17.280> site<02:13:17.579> you 02:13:18.050 --> 02:13:18.060 align:start position:0% entire leg work is done on our site you 02:13:18.060 --> 02:13:20.870 align:start position:0% entire leg work is done on our site you can<02:13:18.179> get<02:13:18.300> a<02:13:18.540> notification<02:13:19.440> it<02:13:19.860> can<02:13:20.099> be<02:13:20.219> like<02:13:20.460> a 02:13:20.870 --> 02:13:20.880 align:start position:0% can get a notification it can be like a 02:13:20.880 --> 02:13:22.910 align:start position:0% can get a notification it can be like a web<02:13:21.000> hook<02:13:21.239> we<02:13:21.840> can<02:13:22.020> like<02:13:22.139> send<02:13:22.380> you<02:13:22.500> a<02:13:22.679> bit<02:13:22.800> of 02:13:22.910 --> 02:13:22.920 align:start position:0% web hook we can like send you a bit of 02:13:22.920 --> 02:13:25.729 align:start position:0% web hook we can like send you a bit of information<02:13:23.159> like<02:13:23.760> using<02:13:24.179> a<02:13:24.300> websocket<02:13:24.840> uh<02:13:25.560> it 02:13:25.729 --> 02:13:25.739 align:start position:0% information like using a websocket uh it 02:13:25.739 --> 02:13:27.589 align:start position:0% information like using a websocket uh it can<02:13:25.860> be<02:13:25.920> essentially<02:13:26.340> whatever<02:13:26.760> whatever<02:13:27.179> you 02:13:27.589 --> 02:13:27.599 align:start position:0% can be essentially whatever whatever you 02:13:27.599 --> 02:13:31.069 align:start position:0% can be essentially whatever whatever you want 02:13:31.069 --> 02:13:31.079 align:start position:0% 02:13:31.079 --> 02:13:37.209 align:start position:0% foreign 02:13:37.209 --> 02:13:37.219 align:start position:0% 02:13:37.219 --> 02:13:40.129 align:start position:0% oh<02:13:38.219> yeah<02:13:38.340> so<02:13:38.699> uh<02:13:39.119> that's<02:13:39.480> actually<02:13:39.719> a<02:13:39.960> great 02:13:40.129 --> 02:13:40.139 align:start position:0% oh yeah so uh that's actually a great 02:13:40.139 --> 02:13:43.010 align:start position:0% oh yeah so uh that's actually a great question<02:13:40.380> so<02:13:41.280> different<02:13:42.119> chains<02:13:42.659> use<02:13:42.780> a 02:13:43.010 --> 02:13:43.020 align:start position:0% question so different chains use a 02:13:43.020 --> 02:13:45.649 align:start position:0% question so different chains use a different<02:13:43.199> like<02:13:43.500> storage<02:13:43.800> uh<02:13:44.579> I<02:13:45.480> would<02:13:45.599> say 02:13:45.649 --> 02:13:45.659 align:start position:0% different like storage uh I would say 02:13:45.659 --> 02:13:46.970 align:start position:0% different like storage uh I would say architecture<02:13:46.199> they<02:13:46.440> might<02:13:46.619> commit<02:13:46.860> to 02:13:46.970 --> 02:13:46.980 align:start position:0% architecture they might commit to 02:13:46.980 --> 02:13:50.209 align:start position:0% architecture they might commit to America<02:13:47.099> Patricia<02:13:47.699> 3<02:13:47.940> Miracle<02:13:48.540> 3<02:13:48.739> uh<02:13:49.739> maybe 02:13:50.209 --> 02:13:50.219 align:start position:0% America Patricia 3 Miracle 3 uh maybe 02:13:50.219 --> 02:13:52.609 align:start position:0% America Patricia 3 Miracle 3 uh maybe even<02:13:50.400> vertical<02:13:50.880> tree<02:13:51.119> and<02:13:51.719> obviously<02:13:52.079> like<02:13:52.440> I 02:13:52.609 --> 02:13:52.619 align:start position:0% even vertical tree and obviously like I 02:13:52.619 --> 02:13:55.609 align:start position:0% even vertical tree and obviously like I said<02:13:52.739> having<02:13:52.980> a<02:13:53.219> generalized<02:13:53.820> verifier<02:13:54.780> it's 02:13:55.609 --> 02:13:55.619 align:start position:0% said having a generalized verifier it's 02:13:55.619 --> 02:13:59.149 align:start position:0% said having a generalized verifier it's like<02:13:55.980> pretty<02:13:56.360> it's<02:13:57.360> not<02:13:57.599> a<02:13:57.900> clean<02:13:58.079> approach<02:13:58.500> so 02:13:59.149 --> 02:13:59.159 align:start position:0% like pretty it's not a clean approach so 02:13:59.159 --> 02:14:01.970 align:start position:0% like pretty it's not a clean approach so we<02:13:59.400> essentially<02:13:59.760> abstract<02:14:00.300> it<02:14:00.719> but<02:14:01.440> by<02:14:01.739> using 02:14:01.970 --> 02:14:01.980 align:start position:0% we essentially abstract it but by using 02:14:01.980 --> 02:14:04.790 align:start position:0% we essentially abstract it but by using a<02:14:02.159> snark<02:14:02.400> and<02:14:03.239> inside<02:14:03.480> the<02:14:03.719> snark<02:14:04.079> itself<02:14:04.440> we 02:14:04.790 --> 02:14:04.800 align:start position:0% a snark and inside the snark itself we 02:14:04.800 --> 02:14:08.030 align:start position:0% a snark and inside the snark itself we just<02:14:04.980> do<02:14:05.880> the<02:14:06.119> proper<02:14:06.719> work<02:14:07.020> like 02:14:08.030 --> 02:14:08.040 align:start position:0% just do the proper work like 02:14:08.040 --> 02:14:10.129 align:start position:0% just do the proper work like you<02:14:08.639> know<02:14:08.820> you<02:14:09.060> go<02:14:09.239> for<02:14:09.420> the<02:14:09.599> for<02:14:09.780> the<02:14:10.020> tree 02:14:10.129 --> 02:14:10.139 align:start position:0% you know you go for the for the tree 02:14:10.139 --> 02:14:11.810 align:start position:0% you know you go for the for the tree like<02:14:10.380> for<02:14:10.500> the<02:14:10.739> for<02:14:10.980> the<02:14:11.280> um<02:14:11.280> through<02:14:11.699> the 02:14:11.810 --> 02:14:11.820 align:start position:0% like for the for the um through the 02:14:11.820 --> 02:14:13.490 align:start position:0% like for the for the um through the elements<02:14:12.119> of<02:14:12.239> the<02:14:12.360> proof<02:14:12.659> and<02:14:12.840> then<02:14:12.960> we<02:14:13.320> can 02:14:13.490 --> 02:14:13.500 align:start position:0% elements of the proof and then we can 02:14:13.500 --> 02:14:15.770 align:start position:0% elements of the proof and then we can like<02:14:13.679> use<02:14:13.860> a<02:14:14.099> specific<02:14:14.340> hashing<02:14:14.820> function<02:14:15.119> so 02:14:15.770 --> 02:14:15.780 align:start position:0% like use a specific hashing function so 02:14:15.780 --> 02:14:18.890 align:start position:0% like use a specific hashing function so for<02:14:15.960> example<02:14:16.340> now<02:14:17.340> Poseidon<02:14:17.940> is<02:14:18.119> Poseidon<02:14:18.659> is 02:14:18.890 --> 02:14:18.900 align:start position:0% for example now Poseidon is Poseidon is 02:14:18.900 --> 02:14:21.890 align:start position:0% for example now Poseidon is Poseidon is uh<02:14:19.500> is<02:14:20.099> is<02:14:20.219> pretty<02:14:20.520> popular 02:14:21.890 --> 02:14:21.900 align:start position:0% uh is is pretty popular 02:14:21.900 --> 02:14:24.410 align:start position:0% uh is is pretty popular um<02:14:22.020> I<02:14:22.560> think<02:14:22.739> that<02:14:22.980> scroll<02:14:23.340> uses<02:14:23.760> Poseidon<02:14:24.239> and 02:14:24.410 --> 02:14:24.420 align:start position:0% um I think that scroll uses Poseidon and 02:14:24.420 --> 02:14:27.770 align:start position:0% um I think that scroll uses Poseidon and also<02:14:24.780> SDK<02:14:25.500> sync<02:14:25.800> uses<02:14:25.980> Poseidon<02:14:26.520> on<02:14:27.360> the<02:14:27.480> avian 02:14:27.770 --> 02:14:27.780 align:start position:0% also SDK sync uses Poseidon on the avian 02:14:27.780 --> 02:14:29.569 align:start position:0% also SDK sync uses Poseidon on the avian like<02:14:28.079> performing<02:14:28.679> Poseidon<02:14:29.099> will<02:14:29.280> be<02:14:29.400> pretty 02:14:29.569 --> 02:14:29.579 align:start position:0% like performing Poseidon will be pretty 02:14:29.579 --> 02:14:31.669 align:start position:0% like performing Poseidon will be pretty expensive<02:14:30.060> so<02:14:30.780> for<02:14:30.960> that<02:14:31.079> reason<02:14:31.260> you<02:14:31.500> cannot 02:14:31.669 --> 02:14:31.679 align:start position:0% expensive so for that reason you cannot 02:14:31.679 --> 02:14:33.350 align:start position:0% expensive so for that reason you cannot verify<02:14:31.980> the<02:14:32.159> proof<02:14:32.400> directly<02:14:32.760> but<02:14:33.060> what<02:14:33.239> you 02:14:33.350 --> 02:14:33.360 align:start position:0% verify the proof directly but what you 02:14:33.360 --> 02:14:34.550 align:start position:0% verify the proof directly but what you can<02:14:33.540> do<02:14:33.599> you<02:14:33.780> can<02:14:33.900> do<02:14:34.139> the<02:14:34.320> entire 02:14:34.550 --> 02:14:34.560 align:start position:0% can do you can do the entire 02:14:34.560 --> 02:14:36.530 align:start position:0% can do you can do the entire verification<02:14:34.920> inside<02:14:35.159> the<02:14:35.400> snark<02:14:35.699> and<02:14:36.360> then 02:14:36.530 --> 02:14:36.540 align:start position:0% verification inside the snark and then 02:14:36.540 --> 02:14:37.850 align:start position:0% verification inside the snark and then on<02:14:36.719> the<02:14:36.900> one<02:14:37.020> you<02:14:37.199> don't<02:14:37.320> really<02:14:37.500> care<02:14:37.679> about 02:14:37.850 --> 02:14:37.860 align:start position:0% on the one you don't really care about 02:14:37.860 --> 02:14:39.890 align:start position:0% on the one you don't really care about the<02:14:38.219> Strunk<02:14:38.639> is<02:14:38.880> like<02:14:39.060> doing<02:14:39.300> you<02:14:39.540> just<02:14:39.719> just 02:14:39.890 --> 02:14:39.900 align:start position:0% the Strunk is like doing you just just 02:14:39.900 --> 02:14:41.990 align:start position:0% the Strunk is like doing you just just verify<02:14:40.380> it<02:14:40.500> so<02:14:40.980> that's<02:14:41.099> how<02:14:41.340> we<02:14:41.460> actually<02:14:41.579> did 02:14:41.990 --> 02:14:42.000 align:start position:0% verify it so that's how we actually did 02:14:42.000 --> 02:14:43.790 align:start position:0% verify it so that's how we actually did it<02:14:42.179> deal<02:14:42.480> with<02:14:42.659> it<02:14:42.840> if<02:14:43.079> we<02:14:43.199> need<02:14:43.380> to<02:14:43.440> have<02:14:43.619> it 02:14:43.790 --> 02:14:43.800 align:start position:0% it deal with it if we need to have it 02:14:43.800 --> 02:14:45.290 align:start position:0% it deal with it if we need to have it abstracted<02:14:44.159> we<02:14:44.340> have<02:14:44.460> it<02:14:44.520> abstracted<02:14:44.940> if<02:14:45.179> we 02:14:45.290 --> 02:14:45.300 align:start position:0% abstracted we have it abstracted if we 02:14:45.300 --> 02:14:49.850 align:start position:0% abstracted we have it abstracted if we don't<02:14:45.420> then<02:14:45.900> we<02:14:46.260> just<02:14:46.440> don't 02:14:49.850 --> 02:14:49.860 align:start position:0% 02:14:49.860 --> 02:14:54.830 align:start position:0% foreign 02:14:54.830 --> 02:14:54.840 align:start position:0% 02:14:54.840 --> 02:15:00.830 align:start position:0% oh<02:14:55.380> yeah 02:15:00.830 --> 02:15:00.840 align:start position:0% 02:15:00.840 --> 02:15:03.109 align:start position:0% oh<02:15:01.380> yeah<02:15:01.619> that's<02:15:01.920> uh<02:15:02.280> that's<02:15:02.639> actually<02:15:02.820> a<02:15:03.000> good 02:15:03.109 --> 02:15:03.119 align:start position:0% oh yeah that's uh that's actually a good 02:15:03.119 --> 02:15:04.790 align:start position:0% oh yeah that's uh that's actually a good question<02:15:03.300> because<02:15:03.599> I<02:15:03.840> think<02:15:03.960> I<02:15:04.139> went<02:15:04.380> super 02:15:04.790 --> 02:15:04.800 align:start position:0% question because I think I went super 02:15:04.800 --> 02:15:07.129 align:start position:0% question because I think I went super technical<02:15:05.280> uh<02:15:06.119> so<02:15:06.300> actually<02:15:06.420> what<02:15:06.719> we<02:15:06.900> do<02:15:07.020> at 02:15:07.129 --> 02:15:07.139 align:start position:0% technical uh so actually what we do at 02:15:07.139 --> 02:15:09.830 align:start position:0% technical uh so actually what we do at Herodotus<02:15:07.739> every<02:15:08.340> two<02:15:09.179> weeks<02:15:09.420> we<02:15:09.540> have<02:15:09.719> some 02:15:09.830 --> 02:15:09.840 align:start position:0% Herodotus every two weeks we have some 02:15:09.840 --> 02:15:11.930 align:start position:0% Herodotus every two weeks we have some internal<02:15:10.199> hackathons<02:15:10.679> and<02:15:11.040> right<02:15:11.400> before<02:15:11.639> the 02:15:11.930 --> 02:15:11.940 align:start position:0% internal hackathons and right before the 02:15:11.940 --> 02:15:14.930 align:start position:0% internal hackathons and right before the merge<02:15:12.300> uh<02:15:13.199> we<02:15:13.500> built<02:15:14.040> a<02:15:14.159> proof<02:15:14.520> of<02:15:14.579> concept 02:15:14.930 --> 02:15:14.940 align:start position:0% merge uh we built a proof of concept 02:15:14.940 --> 02:15:16.850 align:start position:0% merge uh we built a proof of concept that<02:15:15.239> we<02:15:15.360> called<02:15:15.540> merge<02:15:16.020> Swap<02:15:16.320> and 02:15:16.850 --> 02:15:16.860 align:start position:0% that we called merge Swap and 02:15:16.860 --> 02:15:18.830 align:start position:0% that we called merge Swap and essentially<02:15:17.219> we<02:15:17.520> allowed<02:15:17.940> anyone<02:15:18.420> to<02:15:18.659> dump 02:15:18.830 --> 02:15:18.840 align:start position:0% essentially we allowed anyone to dump 02:15:18.840 --> 02:15:21.830 align:start position:0% essentially we allowed anyone to dump their<02:15:19.139> proof<02:15:19.800> of<02:15:19.920> work<02:15:20.460> if<02:15:20.760> on<02:15:21.119> proof<02:15:21.420> of<02:15:21.480> stake 02:15:21.830 --> 02:15:21.840 align:start position:0% their proof of work if on proof of stake 02:15:21.840 --> 02:15:23.390 align:start position:0% their proof of work if on proof of stake and<02:15:22.260> the<02:15:22.380> way<02:15:22.500> how<02:15:22.679> it<02:15:22.800> works<02:15:23.099> would<02:15:23.219> you 02:15:23.390 --> 02:15:23.400 align:start position:0% and the way how it works would you 02:15:23.400 --> 02:15:24.890 align:start position:0% and the way how it works would you literally<02:15:23.699> build<02:15:23.880> the<02:15:24.060> bridge<02:15:24.239> on<02:15:24.540> top<02:15:24.659> of 02:15:24.890 --> 02:15:24.900 align:start position:0% literally build the bridge on top of 02:15:24.900 --> 02:15:27.109 align:start position:0% literally build the bridge on top of this<02:15:25.139> technology<02:15:25.860> and<02:15:26.219> the<02:15:26.340> bridge<02:15:26.579> Works<02:15:27.000> in 02:15:27.109 --> 02:15:27.119 align:start position:0% this technology and the bridge Works in 02:15:27.119 --> 02:15:30.649 align:start position:0% this technology and the bridge Works in a<02:15:27.239> way<02:15:27.360> that<02:15:27.480> you<02:15:27.659> can<02:15:27.780> lock<02:15:28.380> your<02:15:29.400> if<02:15:30.179> proof<02:15:30.599> of 02:15:30.649 --> 02:15:30.659 align:start position:0% a way that you can lock your if proof of 02:15:30.659 --> 02:15:33.770 align:start position:0% a way that you can lock your if proof of work<02:15:30.840> inside<02:15:31.139> a<02:15:31.440> smart<02:15:31.679> contract<02:15:32.159> on<02:15:33.119> if<02:15:33.420> proof 02:15:33.770 --> 02:15:33.780 align:start position:0% work inside a smart contract on if proof 02:15:33.780 --> 02:15:35.750 align:start position:0% work inside a smart contract on if proof of<02:15:33.840> under<02:15:34.020> if<02:15:34.260> proof<02:15:34.619> of<02:15:34.619> work<02:15:34.800> chain<02:15:35.040> you<02:15:35.639> can 02:15:35.750 --> 02:15:35.760 align:start position:0% of under if proof of work chain you can 02:15:35.760 --> 02:15:37.970 align:start position:0% of under if proof of work chain you can prove<02:15:36.060> that<02:15:36.179> you've<02:15:36.360> done<02:15:36.540> it<02:15:36.719> on<02:15:37.139> ethereum 02:15:37.970 --> 02:15:37.980 align:start position:0% prove that you've done it on ethereum 02:15:37.980 --> 02:15:40.010 align:start position:0% prove that you've done it on ethereum proof<02:15:38.219> of<02:15:38.280> stake<02:15:38.579> you<02:15:39.179> can<02:15:39.360> once<02:15:39.719> you<02:15:39.840> the 02:15:40.010 --> 02:15:40.020 align:start position:0% proof of stake you can once you the 02:15:40.020 --> 02:15:42.229 align:start position:0% proof of stake you can once you the proof<02:15:40.260> is<02:15:40.380> verified<02:15:40.679> you<02:15:41.280> can<02:15:41.400> meet<02:15:41.579> the<02:15:41.760> erc20 02:15:42.229 --> 02:15:42.239 align:start position:0% proof is verified you can meet the erc20 02:15:42.239 --> 02:15:44.629 align:start position:0% proof is verified you can meet the erc20 token<02:15:42.780> and<02:15:43.619> you<02:15:43.860> can<02:15:43.920> do<02:15:44.040> whatever<02:15:44.159> you<02:15:44.520> want 02:15:44.629 --> 02:15:44.639 align:start position:0% token and you can do whatever you want 02:15:44.639 --> 02:15:46.370 align:start position:0% token and you can do whatever you want with<02:15:44.820> this<02:15:45.000> token<02:15:45.360> and<02:15:45.780> then<02:15:45.900> if<02:15:46.079> you<02:15:46.199> want<02:15:46.320> to 02:15:46.370 --> 02:15:46.380 align:start position:0% with this token and then if you want to 02:15:46.380 --> 02:15:47.990 align:start position:0% with this token and then if you want to withdraw<02:15:46.800> back<02:15:46.980> to<02:15:47.099> if<02:15:47.400> you're<02:15:47.579> in<02:15:47.699> proof<02:15:47.940> of 02:15:47.990 --> 02:15:48.000 align:start position:0% withdraw back to if you're in proof of 02:15:48.000 --> 02:15:50.569 align:start position:0% withdraw back to if you're in proof of work<02:15:48.420> you<02:15:48.960> just<02:15:49.139> burn<02:15:49.320> it<02:15:49.560> you<02:15:50.040> prove<02:15:50.340> the<02:15:50.400> fact 02:15:50.569 --> 02:15:50.579 align:start position:0% work you just burn it you prove the fact 02:15:50.579 --> 02:15:52.970 align:start position:0% work you just burn it you prove the fact that<02:15:50.760> you<02:15:51.000> burned<02:15:51.599> on<02:15:51.780> the<02:15:51.960> other<02:15:52.020> side<02:15:52.320> and 02:15:52.970 --> 02:15:52.980 align:start position:0% that you burned on the other side and 02:15:52.980 --> 02:15:54.830 align:start position:0% that you burned on the other side and and<02:15:53.219> yeah<02:15:53.400> that's<02:15:53.579> it<02:15:53.820> also<02:15:54.360> in<02:15:54.540> terms<02:15:54.719> of 02:15:54.830 --> 02:15:54.840 align:start position:0% and yeah that's it also in terms of 02:15:54.840 --> 02:15:58.149 align:start position:0% and yeah that's it also in terms of other<02:15:55.380> use<02:15:55.739> cases<02:15:56.040> I<02:15:56.940> think<02:15:57.060> that 02:15:58.149 --> 02:15:58.159 align:start position:0% other use cases I think that 02:15:58.159 --> 02:16:00.770 align:start position:0% other use cases I think that cross-chain<02:15:59.159> collateralization<02:15:59.880> is<02:16:00.480> pretty 02:16:00.770 --> 02:16:00.780 align:start position:0% cross-chain collateralization is pretty 02:16:00.780 --> 02:16:02.990 align:start position:0% cross-chain collateralization is pretty cool<02:16:01.020> because<02:16:01.679> this<02:16:01.980> is<02:16:02.099> the<02:16:02.340> place<02:16:02.520> where<02:16:02.820> you 02:16:02.990 --> 02:16:03.000 align:start position:0% cool because this is the place where you 02:16:03.000 --> 02:16:04.669 align:start position:0% cool because this is the place where you want<02:16:03.179> to<02:16:03.300> avoid<02:16:03.599> latency<02:16:04.020> as<02:16:04.380> much<02:16:04.500> as 02:16:04.669 --> 02:16:04.679 align:start position:0% want to avoid latency as much as 02:16:04.679 --> 02:16:07.490 align:start position:0% want to avoid latency as much as possible<02:16:04.980> and<02:16:05.639> you<02:16:05.820> want<02:16:06.000> to<02:16:06.119> be<02:16:06.500> asynchronous 02:16:07.490 --> 02:16:07.500 align:start position:0% possible and you want to be asynchronous 02:16:07.500 --> 02:16:09.290 align:start position:0% possible and you want to be asynchronous as<02:16:07.739> much<02:16:07.920> as<02:16:08.040> possible<02:16:08.340> and<02:16:08.940> essentially 02:16:09.290 --> 02:16:09.300 align:start position:0% as much as possible and essentially 02:16:09.300 --> 02:16:11.510 align:start position:0% as much as possible and essentially that's<02:16:09.599> that's<02:16:10.020> what<02:16:10.380> we<02:16:10.560> do<02:16:10.679> here<02:16:10.860> because 02:16:11.510 --> 02:16:11.520 align:start position:0% that's that's what we do here because 02:16:11.520 --> 02:16:14.030 align:start position:0% that's that's what we do here because our<02:16:11.820> latency<02:16:12.239> comes<02:16:12.659> only<02:16:12.840> from<02:16:13.320> from<02:16:13.800> the 02:16:14.030 --> 02:16:14.040 align:start position:0% our latency comes only from from the 02:16:14.040 --> 02:16:16.310 align:start position:0% our latency comes only from from the proving<02:16:14.340> time<02:16:14.579> but<02:16:15.300> again<02:16:15.480> using<02:16:16.199> some 02:16:16.310 --> 02:16:16.320 align:start position:0% proving time but again using some 02:16:16.320 --> 02:16:18.229 align:start position:0% proving time but again using some optimistic<02:16:16.860> approaches<02:16:17.159> and<02:16:17.280> so<02:16:17.460> on<02:16:17.579> there<02:16:17.760> a 02:16:18.229 --> 02:16:18.239 align:start position:0% optimistic approaches and so on there a 02:16:18.239 --> 02:16:19.729 align:start position:0% optimistic approaches and so on there a lot<02:16:18.360> of<02:16:18.480> things<02:16:18.659> we<02:16:18.840> can<02:16:19.079> do 02:16:19.729 --> 02:16:19.739 align:start position:0% lot of things we can do 02:16:19.739 --> 02:16:30.709 align:start position:0% lot of things we can do cure<02:16:20.340> I<02:16:20.880> hope<02:16:21.000> it<02:16:21.239> answers<02:16:21.960> the<02:16:22.199> question 02:16:30.709 --> 02:16:30.719 align:start position:0% 02:16:30.719 --> 02:16:32.750 align:start position:0% okay<02:16:31.020> I<02:16:31.440> think<02:16:31.500> that's<02:16:31.619> it<02:16:31.800> I<02:16:32.040> have<02:16:32.219> like<02:16:32.460> three 02:16:32.750 --> 02:16:32.760 align:start position:0% okay I think that's it I have like three 02:16:32.760 --> 02:16:35.629 align:start position:0% okay I think that's it I have like three minutes<02:16:33.000> so<02:16:33.540> I<02:16:33.780> guess<02:16:33.840> we<02:16:34.080> can<02:16:34.200> wrap<02:16:34.380> it<02:16:34.500> up<02:16:35.160> and 02:16:35.629 --> 02:16:35.639 align:start position:0% minutes so I guess we can wrap it up and 02:16:35.639 --> 02:16:38.120 align:start position:0% minutes so I guess we can wrap it up and yeah<02:16:35.820> thanks