WEBVTT Kind: captions Language: en 00:00:00.030 --> 00:00:02.510 align:start position:0% so<00:00:00.659> yeah<00:00:00.810> my<00:00:00.930> name<00:00:01.050> is<00:00:01.079> Jake<00:00:01.380> and<00:00:01.680> we're<00:00:02.429> gonna 00:00:02.510 --> 00:00:02.520 align:start position:0% so yeah my name is Jake and we're gonna 00:00:02.520 --> 00:00:03.619 align:start position:0% so yeah my name is Jake and we're gonna talk<00:00:02.639> about<00:00:02.700> smart<00:00:02.970> contracts<00:00:03.389> and<00:00:03.570> in 00:00:03.619 --> 00:00:03.629 align:start position:0% talk about smart contracts and in 00:00:03.629 --> 00:00:05.300 align:start position:0% talk about smart contracts and in particular<00:00:04.049> how<00:00:04.319> to<00:00:04.350> sort<00:00:04.620> of<00:00:04.680> detect<00:00:05.009> what 00:00:05.300 --> 00:00:05.310 align:start position:0% particular how to sort of detect what 00:00:05.310 --> 00:00:07.700 align:start position:0% particular how to sort of detect what ether<00:00:05.700> scam<00:00:05.940> calls<00:00:06.240> internal<00:00:07.140> transactions 00:00:07.700 --> 00:00:07.710 align:start position:0% ether scam calls internal transactions 00:00:07.710 --> 00:00:10.009 align:start position:0% ether scam calls internal transactions this<00:00:08.460> is<00:00:08.550> notoriously<00:00:08.880> hard<00:00:09.420> sort<00:00:09.809> of<00:00:09.870> thing 00:00:10.009 --> 00:00:10.019 align:start position:0% this is notoriously hard sort of thing 00:00:10.019 --> 00:00:11.330 align:start position:0% this is notoriously hard sort of thing to<00:00:10.110> do<00:00:10.260> and<00:00:10.620> we've<00:00:10.860> heard<00:00:10.950> from<00:00:11.070> lots<00:00:11.190> of 00:00:11.330 --> 00:00:11.340 align:start position:0% to do and we've heard from lots of 00:00:11.340 --> 00:00:12.950 align:start position:0% to do and we've heard from lots of people<00:00:11.580> that<00:00:11.820> it's<00:00:12.150> challenging<00:00:12.509> so<00:00:12.719> I<00:00:12.750> just 00:00:12.950 --> 00:00:12.960 align:start position:0% people that it's challenging so I just 00:00:12.960 --> 00:00:14.839 align:start position:0% people that it's challenging so I just want<00:00:13.110> to<00:00:13.139> kind<00:00:13.320> of<00:00:13.349> present<00:00:13.530> our<00:00:14.400> experiences 00:00:14.839 --> 00:00:14.849 align:start position:0% want to kind of present our experiences 00:00:14.849 --> 00:00:16.460 align:start position:0% want to kind of present our experiences with<00:00:15.089> it<00:00:15.210> issues<00:00:15.450> we've<00:00:15.630> seen<00:00:15.900> and<00:00:16.139> how<00:00:16.410> to 00:00:16.460 --> 00:00:16.470 align:start position:0% with it issues we've seen and how to 00:00:16.470 --> 00:00:17.810 align:start position:0% with it issues we've seen and how to sort<00:00:16.710> of<00:00:16.770> handle<00:00:16.920> these<00:00:17.070> safely<00:00:17.550> and<00:00:17.699> how<00:00:17.760> to 00:00:17.810 --> 00:00:17.820 align:start position:0% sort of handle these safely and how to 00:00:17.820 --> 00:00:19.849 align:start position:0% sort of handle these safely and how to prevent<00:00:18.119> you<00:00:18.869> from<00:00:18.930> having<00:00:19.080> similary<00:00:19.590> sorts 00:00:19.849 --> 00:00:19.859 align:start position:0% prevent you from having similary sorts 00:00:19.859 --> 00:00:22.189 align:start position:0% prevent you from having similary sorts of<00:00:19.920> problems<00:00:20.580> in<00:00:20.730> the<00:00:20.789> future<00:00:21.029> like<00:00:22.020> you<00:00:22.080> said 00:00:22.189 --> 00:00:22.199 align:start position:0% of problems in the future like you said 00:00:22.199 --> 00:00:23.210 align:start position:0% of problems in the future like you said I'm<00:00:22.289> on<00:00:22.380> the<00:00:22.439> crypto<00:00:22.650> currency<00:00:22.949> team<00:00:23.070> at 00:00:23.210 --> 00:00:23.220 align:start position:0% I'm on the crypto currency team at 00:00:23.220 --> 00:00:24.859 align:start position:0% I'm on the crypto currency team at coinbase<00:00:23.460> we're<00:00:23.939> the<00:00:24.150> team<00:00:24.269> that<00:00:24.539> runs<00:00:24.720> our 00:00:24.859 --> 00:00:24.869 align:start position:0% coinbase we're the team that runs our 00:00:24.869 --> 00:00:26.179 align:start position:0% coinbase we're the team that runs our blockchain<00:00:25.199> integrations<00:00:25.710> for<00:00:25.980> all<00:00:26.070> the 00:00:26.179 --> 00:00:26.189 align:start position:0% blockchain integrations for all the 00:00:26.189 --> 00:00:28.099 align:start position:0% blockchain integrations for all the currencies<00:00:26.580> hot<00:00:26.910> wallet<00:00:27.240> cold<00:00:27.449> storage<00:00:27.750> sends 00:00:28.099 --> 00:00:28.109 align:start position:0% currencies hot wallet cold storage sends 00:00:28.109 --> 00:00:30.200 align:start position:0% currencies hot wallet cold storage sends receives<00:00:28.490> we're<00:00:29.490> hiring<00:00:29.699> if<00:00:30.029> that's 00:00:30.200 --> 00:00:30.210 align:start position:0% receives we're hiring if that's 00:00:30.210 --> 00:00:31.939 align:start position:0% receives we're hiring if that's interesting<00:00:30.630> to<00:00:30.689> you<00:00:30.810> just<00:00:31.529> come<00:00:31.650> talk<00:00:31.740> to<00:00:31.830> me 00:00:31.939 --> 00:00:31.949 align:start position:0% interesting to you just come talk to me 00:00:31.949 --> 00:00:34.970 align:start position:0% interesting to you just come talk to me afterwards<00:00:32.660> so<00:00:33.660> yeah<00:00:33.809> we<00:00:34.320> started<00:00:34.559> though<00:00:34.770> and 00:00:34.970 --> 00:00:34.980 align:start position:0% afterwards so yeah we started though and 00:00:34.980 --> 00:00:36.970 align:start position:0% afterwards so yeah we started though and so<00:00:35.280> who<00:00:35.520> should<00:00:35.610> care<00:00:35.910> about<00:00:36.090> this<00:00:36.210> stuff 00:00:36.970 --> 00:00:36.980 align:start position:0% so who should care about this stuff 00:00:36.980 --> 00:00:39.470 align:start position:0% so who should care about this stuff these<00:00:37.980> are<00:00:38.129> kind<00:00:38.280> of<00:00:38.309> the<00:00:38.399> primary<00:00:38.670> three<00:00:39.270> we 00:00:39.470 --> 00:00:39.480 align:start position:0% these are kind of the primary three we 00:00:39.480 --> 00:00:41.060 align:start position:0% these are kind of the primary three we see<00:00:39.660> here<00:00:39.840> is<00:00:39.930> like<00:00:40.110> exchanges<00:00:40.620> wallets<00:00:40.980> and 00:00:41.060 --> 00:00:41.070 align:start position:0% see here is like exchanges wallets and 00:00:41.070 --> 00:00:43.040 align:start position:0% see here is like exchanges wallets and explores<00:00:41.460> the<00:00:42.300> highest<00:00:42.600> risk<00:00:42.780> comes<00:00:42.930> to 00:00:43.040 --> 00:00:43.050 align:start position:0% explores the highest risk comes to 00:00:43.050 --> 00:00:44.810 align:start position:0% explores the highest risk comes to exchanges<00:00:43.469> which<00:00:43.590> we'll<00:00:43.739> talk<00:00:43.860> about<00:00:44.040> but 00:00:44.810 --> 00:00:44.820 align:start position:0% exchanges which we'll talk about but 00:00:44.820 --> 00:00:46.580 align:start position:0% exchanges which we'll talk about but really<00:00:44.940> it<00:00:45.120> matters<00:00:45.360> for<00:00:45.390> everybody 00:00:46.580 --> 00:00:46.590 align:start position:0% really it matters for everybody 00:00:46.590 --> 00:00:48.229 align:start position:0% really it matters for everybody and<00:00:46.770> anybody<00:00:47.129> you<00:00:47.550> know<00:00:47.820> building<00:00:48.149> on 00:00:48.229 --> 00:00:48.239 align:start position:0% and anybody you know building on 00:00:48.239 --> 00:00:50.990 align:start position:0% and anybody you know building on aetherium<00:00:48.660> and<00:00:49.649> the<00:00:49.829> reason<00:00:50.129> is<00:00:50.219> because<00:00:50.309> if 00:00:50.990 --> 00:00:51.000 align:start position:0% aetherium and the reason is because if 00:00:51.000 --> 00:00:53.029 align:start position:0% aetherium and the reason is because if you're<00:00:51.239> sort<00:00:51.420> of<00:00:51.480> accepting<00:00:51.960> deposits<00:00:52.110> of<00:00:52.920> any 00:00:53.029 --> 00:00:53.039 align:start position:0% you're sort of accepting deposits of any 00:00:53.039 --> 00:00:54.650 align:start position:0% you're sort of accepting deposits of any sorts<00:00:53.340> of<00:00:53.370> aetherium<00:00:53.760> there's<00:00:54.420> different 00:00:54.650 --> 00:00:54.660 align:start position:0% sorts of aetherium there's different 00:00:54.660 --> 00:00:56.479 align:start position:0% sorts of aetherium there's different ways<00:00:54.750> that<00:00:54.930> can<00:00:55.050> happen<00:00:55.199> and<00:00:55.530> so<00:00:55.860> your<00:00:56.039> primary 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and credits to accounts or to 00:01:02.550 --> 00:01:04.310 align:start position:0% debits and credits to accounts or to update<00:01:03.090> balances<00:01:03.660> or<00:01:03.870> whatever<00:01:04.170> you're 00:01:04.310 --> 00:01:04.320 align:start position:0% update balances or whatever you're 00:01:04.320 --> 00:01:06.320 align:start position:0% update balances or whatever you're trying<00:01:04.559> to<00:01:04.710> do<00:01:05.129> here<00:01:05.309> and<00:01:05.580> so<00:01:06.000> if<00:01:06.060> we<00:01:06.150> take<00:01:06.270> a 00:01:06.320 --> 00:01:06.330 align:start position:0% trying to do here and so if we take a 00:01:06.330 --> 00:01:08.240 align:start position:0% trying to do here and so if we take a transaction<00:01:06.869> like<00:01:06.990> this<00:01:07.229> we're<00:01:07.950> gonna<00:01:08.010> go 00:01:08.240 --> 00:01:08.250 align:start position:0% transaction like this we're gonna go 00:01:08.250 --> 00:01:10.160 align:start position:0% transaction like this we're gonna go here<00:01:08.549> and<00:01:08.729> you<00:01:09.119> know<00:01:09.240> inspect<00:01:09.900> it<00:01:10.020> and<00:01:10.110> say 00:01:10.160 --> 00:01:10.170 align:start position:0% here and you know inspect it and say 00:01:10.170 --> 00:01:12.289 align:start position:0% here and you know inspect it and say okay<00:01:10.350> we<00:01:10.470> should<00:01:10.530> credit<00:01:10.770> alice<00:01:11.130> 1/8<00:01:11.490> and<00:01:11.729> we 00:01:12.289 --> 00:01:12.299 align:start position:0% okay we should credit alice 1/8 and we 00:01:12.299 --> 00:01:14.960 align:start position:0% okay we should credit alice 1/8 and we do<00:01:12.420> that<00:01:12.570> but<00:01:13.560> the<00:01:13.830> risk<00:01:14.040> here<00:01:14.310> is<00:01:14.340> you<00:01:14.880> know 00:01:14.960 --> 00:01:14.970 align:start position:0% do that but the risk here is you know 00:01:14.970 --> 00:01:15.800 align:start position:0% do that but the risk here is you know what<00:01:15.119> if<00:01:15.210> that's<00:01:15.270> not<00:01:15.390> actually<00:01:15.600> what 00:01:15.800 --> 00:01:15.810 align:start position:0% what if that's not actually what 00:01:15.810 --> 00:01:17.539 align:start position:0% what if that's not actually what happened<00:01:16.140> right<00:01:16.740> what<00:01:16.920> if<00:01:17.009> we<00:01:17.100> shouldn't<00:01:17.430> have 00:01:17.539 --> 00:01:17.549 align:start position:0% happened right what if we shouldn't have 00:01:17.549 --> 00:01:19.130 align:start position:0% happened right what if we shouldn't have credit<00:01:17.790> as<00:01:17.880> Alice's<00:01:18.240> and<00:01:18.689> there's<00:01:18.840> some<00:01:18.960> sort 00:01:19.130 --> 00:01:19.140 align:start position:0% credit as Alice's and there's some sort 00:01:19.140 --> 00:01:21.350 align:start position:0% credit as Alice's and there's some sort of<00:01:19.170> bug<00:01:19.350> in<00:01:19.530> our<00:01:19.590> code<00:01:19.830> this<00:01:20.759> is<00:01:20.909> what<00:01:21.030> comes<00:01:21.180> up 00:01:21.350 --> 00:01:21.360 align:start position:0% of bug in our code this is what comes up 00:01:21.360 --> 00:01:22.760 align:start position:0% of bug in our code this is what comes up with<00:01:21.479> contracts<00:01:21.900> because<00:01:22.170> it's<00:01:22.320> not<00:01:22.560> as 00:01:22.760 --> 00:01:22.770 align:start position:0% with contracts because it's not as 00:01:22.770 --> 00:01:24.200 align:start position:0% with contracts because it's not as straightforward<00:01:23.040> thing<00:01:23.430> to<00:01:23.549> do<00:01:23.670> and<00:01:23.880> there's 00:01:24.200 --> 00:01:24.210 align:start position:0% straightforward thing to do and there's 00:01:24.210 --> 00:01:25.789 align:start position:0% straightforward thing to do and there's a<00:01:24.270> lot<00:01:24.420> of<00:01:24.450> nuance<00:01:24.840> to<00:01:24.930> how<00:01:25.110> to<00:01:25.170> handle<00:01:25.439> it<00:01:25.590> and 00:01:25.789 --> 00:01:25.799 align:start position:0% a lot of nuance to how to handle it and 00:01:25.799 --> 00:01:28.730 align:start position:0% a lot of nuance to how to handle it and so<00:01:26.640> what<00:01:27.150> this<00:01:27.240> can<00:01:27.420> lead<00:01:27.630> to<00:01:27.659> is<00:01:28.110> a<00:01:28.470> couple<00:01:28.710> of 00:01:28.730 --> 00:01:28.740 align:start position:0% so what this can lead to is a couple of 00:01:28.740 --> 00:01:29.620 align:start position:0% so what this can lead to is a couple of different<00:01:28.829> things 00:01:29.620 --> 00:01:29.630 align:start position:0% different things 00:01:29.630 --> 00:01:31.760 align:start position:0% different things invalid<00:01:30.630> data<00:01:30.780> is<00:01:31.020> sort<00:01:31.290> of<00:01:31.350> the<00:01:31.470> first<00:01:31.650> one 00:01:31.760 --> 00:01:31.770 align:start position:0% invalid data is sort of the first one 00:01:31.770 --> 00:01:33.770 align:start position:0% invalid data is sort of the first one here<00:01:32.009> right<00:01:32.220> just<00:01:32.250> having<00:01:33.090> bad<00:01:33.240> data<00:01:33.479> showing 00:01:33.770 --> 00:01:33.780 align:start position:0% here right just having bad data showing 00:01:33.780 --> 00:01:36.260 align:start position:0% here right just having bad data showing a<00:01:33.960> wrong<00:01:34.110> account<00:01:34.439> balance<00:01:34.829> is<00:01:35.400> you<00:01:36.000> know<00:01:36.090> not 00:01:36.260 --> 00:01:36.270 align:start position:0% a wrong account balance is you know not 00:01:36.270 --> 00:01:38.690 align:start position:0% a wrong account balance is you know not ideal<00:01:36.570> it's<00:01:37.470> not<00:01:37.650> the<00:01:37.770> worst<00:01:37.920> but<00:01:38.310> it<00:01:38.430> can<00:01:38.579> lead 00:01:38.690 --> 00:01:38.700 align:start position:0% ideal it's not the worst but it can lead 00:01:38.700 --> 00:01:40.069 align:start position:0% ideal it's not the worst but it can lead to<00:01:38.759> pretty<00:01:38.970> bad<00:01:39.150> experiences<00:01:39.689> if<00:01:39.840> somebody 00:01:40.069 --> 00:01:40.079 align:start position:0% to pretty bad experiences if somebody 00:01:40.079 --> 00:01:41.330 align:start position:0% to pretty bad experiences if somebody thinks<00:01:40.259> they<00:01:40.350> have<00:01:40.380> 10<00:01:40.619> 8th<00:01:40.770> and<00:01:41.040> they<00:01:41.100> try<00:01:41.310> and 00:01:41.330 --> 00:01:41.340 align:start position:0% thinks they have 10 8th and they try and 00:01:41.340 --> 00:01:42.800 align:start position:0% thinks they have 10 8th and they try and send<00:01:41.640> that<00:01:41.790> and<00:01:41.909> then<00:01:42.000> it<00:01:42.119> just<00:01:42.210> consistently 00:01:42.800 --> 00:01:42.810 align:start position:0% send that and then it just consistently 00:01:42.810 --> 00:01:44.359 align:start position:0% send that and then it just consistently fails<00:01:43.079> they<00:01:43.680> might<00:01:43.860> switch<00:01:44.009> to<00:01:44.250> a<00:01:44.280> different 00:01:44.359 --> 00:01:44.369 align:start position:0% fails they might switch to a different 00:01:44.369 --> 00:01:46.910 align:start position:0% fails they might switch to a different wallet<00:01:44.820> and<00:01:45.689> if<00:01:46.049> you<00:01:46.140> have<00:01:46.229> systems<00:01:46.619> building 00:01:46.910 --> 00:01:46.920 align:start position:0% wallet and if you have systems building 00:01:46.920 --> 00:01:48.679 align:start position:0% wallet and if you have systems building on<00:01:47.340> top<00:01:47.640> of<00:01:47.820> this<00:01:47.939> if<00:01:48.119> it's<00:01:48.240> some<00:01:48.390> sort<00:01:48.540> of<00:01:48.570> API 00:01:48.679 --> 00:01:48.689 align:start position:0% on top of this if it's some sort of API 00:01:48.689 --> 00:01:50.899 align:start position:0% on top of this if it's some sort of API and<00:01:49.229> you<00:01:49.259> have<00:01:49.409> downstream<00:01:49.860> customers<00:01:50.310> then 00:01:50.899 --> 00:01:50.909 align:start position:0% and you have downstream customers then 00:01:50.909 --> 00:01:52.310 align:start position:0% and you have downstream customers then they're<00:01:51.299> gonna<00:01:51.390> get<00:01:51.570> bad<00:01:51.720> data<00:01:51.990> and<00:01:52.229> they're 00:01:52.310 --> 00:01:52.320 align:start position:0% they're gonna get bad data and they're 00:01:52.320 --> 00:01:54.109 align:start position:0% they're gonna get bad data and they're gonna<00:01:52.409> have<00:01:52.530> to<00:01:52.560> update<00:01:52.950> accordingly<00:01:53.700> their 00:01:54.109 --> 00:01:54.119 align:start position:0% gonna have to update accordingly their 00:01:54.119 --> 00:01:55.249 align:start position:0% gonna have to update accordingly their database<00:01:54.509> and<00:01:54.689> that's<00:01:54.899> gonna<00:01:54.990> be<00:01:55.140> pretty 00:01:55.249 --> 00:01:55.259 align:start position:0% database and that's gonna be pretty 00:01:55.259 --> 00:01:56.899 align:start position:0% database and that's gonna be pretty challenging<00:01:55.530> and<00:01:55.950> there's<00:01:56.430> not<00:01:56.520> really<00:01:56.700> good 00:01:56.899 --> 00:01:56.909 align:start position:0% challenging and there's not really good 00:01:56.909 --> 00:01:58.399 align:start position:0% challenging and there's not really good ways<00:01:57.060> to<00:01:57.090> handle<00:01:57.329> that<00:01:57.450> so<00:01:57.960> you<00:01:58.020> want<00:01:58.170> to<00:01:58.229> avoid 00:01:58.399 --> 00:01:58.409 align:start position:0% ways to handle that so you want to avoid 00:01:58.409 --> 00:02:00.950 align:start position:0% ways to handle that so you want to avoid this<00:01:58.590> sort<00:01:58.890> of<00:01:58.950> as<00:01:59.159> much<00:01:59.340> as<00:01:59.520> you<00:01:59.640> can<00:01:59.840> and<00:02:00.840> like 00:02:00.950 --> 00:02:00.960 align:start position:0% this sort of as much as you can and like 00:02:00.960 --> 00:02:02.179 align:start position:0% this sort of as much as you can and like I<00:02:01.020> said<00:02:01.140> the<00:02:01.290> real<00:02:01.439> risk<00:02:01.680> is<00:02:01.829> actually<00:02:02.100> two 00:02:02.179 --> 00:02:02.189 align:start position:0% I said the real risk is actually two 00:02:02.189 --> 00:02:04.039 align:start position:0% I said the real risk is actually two exchanges<00:02:02.610> here<00:02:02.820> with<00:02:03.180> lost<00:02:03.420> funds<00:02:03.719> because 00:02:04.039 --> 00:02:04.049 align:start position:0% exchanges here with lost funds because 00:02:04.049 --> 00:02:05.600 align:start position:0% exchanges here with lost funds because what<00:02:04.200> they<00:02:04.350> can<00:02:04.530> do<00:02:04.680> is<00:02:05.040> this<00:02:05.159> type<00:02:05.369> of<00:02:05.399> attack 00:02:05.600 --> 00:02:05.610 align:start position:0% what they can do is this type of attack 00:02:05.610 --> 00:02:08.749 align:start position:0% what they can do is this type of attack where<00:02:06.149> you<00:02:06.750> send<00:02:07.049> in<00:02:07.369> ether<00:02:08.369> but<00:02:08.580> you<00:02:08.640> don't 00:02:08.749 --> 00:02:08.759 align:start position:0% where you send in ether but you don't 00:02:08.759 --> 00:02:10.190 align:start position:0% where you send in ether but you don't really<00:02:09.000> it<00:02:09.209> just<00:02:09.360> kind<00:02:09.509> of<00:02:09.539> looks<00:02:09.780> like<00:02:09.989> it<00:02:10.140> you 00:02:10.190 --> 00:02:10.200 align:start position:0% really it just kind of looks like it you 00:02:10.200 --> 00:02:12.140 align:start position:0% really it just kind of looks like it you can<00:02:10.319> trick<00:02:10.500> the<00:02:10.619> system<00:02:10.950> and<00:02:11.160> then<00:02:11.790> they<00:02:11.970> can 00:02:12.140 --> 00:02:12.150 align:start position:0% can trick the system and then they can 00:02:12.150 --> 00:02:13.880 align:start position:0% can trick the system and then they can sell<00:02:12.540> that<00:02:12.720> for<00:02:12.780> some<00:02:13.080> other<00:02:13.200> currency<00:02:13.620> and 00:02:13.880 --> 00:02:13.890 align:start position:0% sell that for some other currency and 00:02:13.890 --> 00:02:16.370 align:start position:0% sell that for some other currency and it<00:02:14.040> off<00:02:14.160> somewhere<00:02:14.520> else<00:02:14.730> or<00:02:14.850> they<00:02:15.240> can<00:02:15.540> you 00:02:16.370 --> 00:02:16.380 align:start position:0% it off somewhere else or they can you 00:02:16.380 --> 00:02:17.960 align:start position:0% it off somewhere else or they can you know<00:02:16.440> just<00:02:16.710> send<00:02:16.860> off<00:02:17.040> ether<00:02:17.520> and<00:02:17.760> in 00:02:17.960 --> 00:02:17.970 align:start position:0% know just send off ether and in 00:02:17.970 --> 00:02:19.430 align:start position:0% know just send off ether and in exchanges<00:02:18.450> cases<00:02:18.780> a<00:02:18.810> lot<00:02:19.050> of<00:02:19.110> them<00:02:19.290> have 00:02:19.430 --> 00:02:19.440 align:start position:0% exchanges cases a lot of them have 00:02:19.440 --> 00:02:20.960 align:start position:0% exchanges cases a lot of them have pooled<00:02:19.770> wallets<00:02:20.190> so<00:02:20.280> everybody's<00:02:20.610> funds<00:02:20.819> are 00:02:20.960 --> 00:02:20.970 align:start position:0% pooled wallets so everybody's funds are 00:02:20.970 --> 00:02:23.660 align:start position:0% pooled wallets so everybody's funds are together<00:02:21.120> so<00:02:21.840> if<00:02:22.200> you<00:02:22.290> send<00:02:22.530> in<00:02:22.709> and<00:02:23.040> you<00:02:23.430> send 00:02:23.660 --> 00:02:23.670 align:start position:0% together so if you send in and you send 00:02:23.670 --> 00:02:24.920 align:start position:0% together so if you send in and you send back<00:02:23.790> out<00:02:23.970> it's<00:02:24.209> probably<00:02:24.540> not<00:02:24.600> going<00:02:24.750> to<00:02:24.810> be 00:02:24.920 --> 00:02:24.930 align:start position:0% back out it's probably not going to be 00:02:24.930 --> 00:02:26.210 align:start position:0% back out it's probably not going to be the<00:02:25.020> same<00:02:25.200> ether<00:02:25.410> it's<00:02:25.770> gonna<00:02:25.860> be<00:02:26.010> something 00:02:26.210 --> 00:02:26.220 align:start position:0% the same ether it's gonna be something 00:02:26.220 --> 00:02:27.199 align:start position:0% the same ether it's gonna be something different<00:02:26.250> and<00:02:26.670> so<00:02:26.760> you<00:02:26.819> can<00:02:26.970> actually<00:02:27.060> just 00:02:27.199 --> 00:02:27.209 align:start position:0% different and so you can actually just 00:02:27.209 --> 00:02:28.730 align:start position:0% different and so you can actually just steal<00:02:27.540> if<00:02:27.750> you're<00:02:27.930> in<00:02:28.020> that<00:02:28.110> way<00:02:28.290> and<00:02:28.530> continue 00:02:28.730 --> 00:02:28.740 align:start position:0% steal if you're in that way and continue 00:02:28.740 --> 00:02:32.330 align:start position:0% steal if you're in that way and continue this<00:02:29.069> until<00:02:29.400> you<00:02:29.700> know<00:02:29.819> you're<00:02:29.940> caught<00:02:30.180> and<00:02:31.340> so 00:02:32.330 --> 00:02:32.340 align:start position:0% this until you know you're caught and so 00:02:32.340 --> 00:02:34.100 align:start position:0% this until you know you're caught and so if<00:02:32.670> you<00:02:32.790> have<00:02:33.180> these<00:02:33.360> types<00:02:33.600> of<00:02:33.660> mistakes<00:02:34.020> this 00:02:34.100 --> 00:02:34.110 align:start position:0% if you have these types of mistakes this 00:02:34.110 --> 00:02:35.360 align:start position:0% if you have these types of mistakes this is<00:02:34.200> the<00:02:34.320> types<00:02:34.500> of<00:02:34.590> headlines<00:02:34.920> you<00:02:35.040> might<00:02:35.190> see 00:02:35.360 --> 00:02:35.370 align:start position:0% is the types of headlines you might see 00:02:35.370 --> 00:02:38.630 align:start position:0% is the types of headlines you might see written<00:02:35.520> about<00:02:35.760> you<00:02:35.970> it's<00:02:36.900> it's<00:02:37.680> not<00:02:37.830> good<00:02:38.070> if 00:02:38.630 --> 00:02:38.640 align:start position:0% written about you it's it's not good if 00:02:38.640 --> 00:02:40.280 align:start position:0% written about you it's it's not good if you<00:02:38.790> see<00:02:38.910> hacker<00:02:39.090> one<00:02:39.330> reports<00:02:39.690> like<00:02:39.870> this<00:02:40.050> you 00:02:40.280 --> 00:02:40.290 align:start position:0% you see hacker one reports like this you 00:02:40.290 --> 00:02:41.750 align:start position:0% you see hacker one reports like this you also<00:02:40.470> don't<00:02:40.800> want<00:02:41.010> to<00:02:41.070> see<00:02:41.220> these<00:02:41.370> kinds<00:02:41.700> of 00:02:41.750 --> 00:02:41.760 align:start position:0% also don't want to see these kinds of 00:02:41.760 --> 00:02:43.850 align:start position:0% also don't want to see these kinds of things<00:02:41.820> and<00:02:42.810> this<00:02:42.930> is<00:02:42.989> what<00:02:43.260> we<00:02:43.380> sort<00:02:43.590> of<00:02:43.680> saw 00:02:43.850 --> 00:02:43.860 align:start position:0% things and this is what we sort of saw 00:02:43.860 --> 00:02:47.330 align:start position:0% things and this is what we sort of saw at<00:02:44.730> some<00:02:44.910> point<00:02:45.060> early<00:02:45.090> in<00:02:45.209> the<00:02:45.300> year<00:02:45.450> and<00:02:46.340> yeah 00:02:47.330 --> 00:02:47.340 align:start position:0% at some point early in the year and yeah 00:02:47.340 --> 00:02:50.390 align:start position:0% at some point early in the year and yeah you<00:02:47.820> don't<00:02:47.970> want<00:02:48.120> that<00:02:48.300> and<00:02:48.570> so<00:02:49.230> what<00:02:49.920> can<00:02:50.190> go 00:02:50.390 --> 00:02:50.400 align:start position:0% you don't want that and so what can go 00:02:50.400 --> 00:02:53.270 align:start position:0% you don't want that and so what can go wrong<00:02:50.580> here<00:02:50.790> and<00:02:51.270> like<00:02:52.050> how<00:02:52.200> do<00:02:52.260> we<00:02:52.350> fix<00:02:52.590> it<00:02:52.800> so 00:02:53.270 --> 00:02:53.280 align:start position:0% wrong here and like how do we fix it so 00:02:53.280 --> 00:02:54.500 align:start position:0% wrong here and like how do we fix it so start<00:02:53.519> that<00:02:53.670> we<00:02:53.820> need<00:02:53.970> to<00:02:54.060> talk<00:02:54.209> about<00:02:54.360> how 00:02:54.500 --> 00:02:54.510 align:start position:0% start that we need to talk about how 00:02:54.510 --> 00:02:57.080 align:start position:0% start that we need to talk about how etherium<00:02:54.900> moves<00:02:55.170> so<00:02:55.980> as<00:02:56.519> I'm<00:02:56.640> sure<00:02:56.790> most<00:02:56.910> of<00:02:57.030> us 00:02:57.080 --> 00:02:57.090 align:start position:0% etherium moves so as I'm sure most of us 00:02:57.090 --> 00:02:58.310 align:start position:0% etherium moves so as I'm sure most of us are<00:02:57.239> familiar<00:02:57.300> with<00:02:57.540> everything<00:02:57.989> happens<00:02:58.230> in 00:02:58.310 --> 00:02:58.320 align:start position:0% are familiar with everything happens in 00:02:58.320 --> 00:02:59.720 align:start position:0% are familiar with everything happens in a<00:02:58.380> block<00:02:58.620> then<00:02:59.190> you<00:02:59.280> have<00:02:59.430> a<00:02:59.459> set<00:02:59.700> of 00:02:59.720 --> 00:02:59.730 align:start position:0% a block then you have a set of 00:02:59.730 --> 00:03:02.090 align:start position:0% a block then you have a set of transactions<00:03:00.390> and<00:03:01.260> in<00:03:01.350> those<00:03:01.500> transactions 00:03:02.090 --> 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you<00:03:13.350> can<00:03:13.470> also<00:03:13.590> have<00:03:13.769> this<00:03:13.830> other 00:03:13.970 --> 00:03:13.980 align:start position:0% another and you can also have this other 00:03:13.980 --> 00:03:16.100 align:start position:0% another and you can also have this other bucket<00:03:14.430> here<00:03:14.610> which<00:03:14.760> is<00:03:14.880> like<00:03:15.030> contracts<00:03:15.600> and 00:03:16.100 --> 00:03:16.110 align:start position:0% bucket here which is like contracts and 00:03:16.110 --> 00:03:17.810 align:start position:0% bucket here which is like contracts and contract<00:03:16.530> can<00:03:16.709> do<00:03:16.800> pretty<00:03:16.980> clever<00:03:17.430> things 00:03:17.810 --> 00:03:17.820 align:start position:0% contract can do pretty clever things 00:03:17.820 --> 00:03:21.500 align:start position:0% contract can do pretty clever things which<00:03:18.750> we'll<00:03:18.900> talk<00:03:19.019> about<00:03:19.140> here<00:03:20.239> but<00:03:21.239> the 00:03:21.500 --> 00:03:21.510 align:start position:0% which we'll talk about here but the 00:03:21.510 --> 00:03:22.729 align:start position:0% which we'll talk about here but the account<00:03:21.750> transfer<00:03:22.049> is<00:03:22.170> like<00:03:22.440> I<00:03:22.470> said<00:03:22.650> are 00:03:22.729 --> 00:03:22.739 align:start position:0% account transfer is like I said are 00:03:22.739 --> 00:03:23.690 align:start position:0% account transfer is like I said are pretty<00:03:22.890> straightforward<00:03:23.130> this<00:03:23.430> is<00:03:23.579> what 00:03:23.690 --> 00:03:23.700 align:start position:0% pretty straightforward this is what 00:03:23.700 --> 00:03:25.130 align:start position:0% pretty straightforward this is what you'll<00:03:23.820> see<00:03:23.940> on<00:03:24.030> ether<00:03:24.269> scan<00:03:24.510> and<00:03:24.870> this<00:03:25.019> is 00:03:25.130 --> 00:03:25.140 align:start position:0% you'll see on ether scan and this is 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there's a to all that's pretty easy to do<00:03:36.120> and<00:03:36.329> there's<00:03:36.570> not<00:03:36.660> really<00:03:36.720> much<00:03:36.959> risk<00:03:37.260> here 00:03:37.490 --> 00:03:37.500 align:start position:0% do and there's not really much risk here 00:03:37.500 --> 00:03:38.900 align:start position:0% do and there's not really much risk here if<00:03:37.590> it<00:03:37.680> says<00:03:37.890> the<00:03:37.980> transaction<00:03:38.310> happened<00:03:38.820> in 00:03:38.900 --> 00:03:38.910 align:start position:0% if it says the transaction happened in 00:03:38.910 --> 00:03:40.940 align:start position:0% if it says the transaction happened in this<00:03:39.000> format<00:03:39.360> it<00:03:39.570> did<00:03:40.260> and<00:03:40.470> you're<00:03:40.680> pretty 00:03:40.940 --> 00:03:40.950 align:start position:0% this format it did and you're pretty 00:03:40.950 --> 00:03:42.080 align:start position:0% this format it did and you're pretty good<00:03:41.160> to<00:03:41.250> go 00:03:42.080 --> 00:03:42.090 align:start position:0% good to go 00:03:42.090 --> 00:03:43.430 align:start position:0% good to go but<00:03:42.480> where<00:03:42.660> it<00:03:42.780> gets<00:03:42.900> complicated<00:03:43.049> is 00:03:43.430 --> 00:03:43.440 align:start position:0% but where it gets complicated is 00:03:43.440 --> 00:03:44.660 align:start position:0% but where it gets complicated is contract<00:03:43.890> transfers<00:03:44.250> they<00:03:44.370> might<00:03:44.519> look<00:03:44.610> like 00:03:44.660 --> 00:03:44.670 align:start position:0% contract transfers they might look like 00:03:44.670 --> 00:03:46.699 align:start position:0% contract transfers they might look like this<00:03:45.030> so<00:03:45.600> now<00:03:45.720> instead<00:03:45.900> of<00:03:46.200> you<00:03:46.350> know<00:03:46.410> which<00:03:46.590> is 00:03:46.699 --> 00:03:46.709 align:start position:0% this so now instead of you know which is 00:03:46.709 --> 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position:0% up and there what's really sort of difficult<00:03:53.820> about<00:03:53.940> these<00:03:54.180> is<00:03:54.390> that<00:03:54.540> this<00:03:54.690> is 00:03:54.830 --> 00:03:54.840 align:start position:0% difficult about these is that this is 00:03:54.840 --> 00:03:56.720 align:start position:0% difficult about these is that this is custom<00:03:55.200> code<00:03:55.440> people<00:03:55.650> write<00:03:55.980> so<00:03:56.459> they<00:03:56.579> have<00:03:56.700> a 00:03:56.720 --> 00:03:56.730 align:start position:0% custom code people write so they have a 00:03:56.730 --> 00:03:58.580 align:start position:0% custom code people write so they have a lot<00:03:57.000> of<00:03:57.180> room<00:03:57.420> outside<00:03:57.870> of<00:03:58.200> just<00:03:58.320> what<00:03:58.500> the 00:03:58.580 --> 00:03:58.590 align:start position:0% lot of room outside of just what the 00:03:58.590 --> 00:04:00.410 align:start position:0% lot of room outside of just what the protocol<00:03:58.980> allows<00:03:59.220> to<00:03:59.459> trick<00:03:59.730> you<00:03:59.880> and<00:04:00.060> to 00:04:00.410 --> 00:04:00.420 align:start position:0% protocol allows to trick you and to 00:04:00.420 --> 00:04:02.630 align:start position:0% protocol allows to trick you and to specifically<00:04:01.049> target<00:04:01.380> like<00:04:01.980> issues<00:04:02.400> in<00:04:02.549> your 00:04:02.630 --> 00:04:02.640 align:start position:0% specifically target like issues in your 00:04:02.640 --> 00:04:04.880 align:start position:0% specifically target like issues in your system<00:04:03.060> and<00:04:03.269> you<00:04:03.329> know<00:04:04.290> attack<00:04:04.650> you<00:04:04.769> because 00:04:04.880 --> 00:04:04.890 align:start position:0% system and you know attack you because 00:04:04.890 --> 00:04:07.819 align:start position:0% system and you know attack you because of<00:04:05.160> it<00:04:05.280> and<00:04:05.459> so<00:04:06.090> there's<00:04:06.810> not<00:04:06.930> a<00:04:06.989> great<00:04:07.110> API<00:04:07.709> for 00:04:07.819 --> 00:04:07.829 align:start position:0% of it and so there's not a great API for 00:04:07.829 --> 00:04:09.800 align:start position:0% of it and so there's not a great API for this<00:04:08.130> what<00:04:09.030> you<00:04:09.120> have<00:04:09.239> to<00:04:09.299> use<00:04:09.420> this<00:04:09.630> API 00:04:09.800 --> 00:04:09.810 align:start position:0% this what you have to use this API 00:04:09.810 --> 00:04:12.110 align:start position:0% this what you have to use this API called<00:04:10.200> the<00:04:10.290> tracing<00:04:10.709> API<00:04:10.950> which<00:04:11.549> is<00:04:11.700> fairly 00:04:12.110 --> 00:04:12.120 align:start position:0% called the tracing API which is fairly 00:04:12.120 --> 00:04:14.479 align:start position:0% called the tracing API which is fairly low-level<00:04:12.420> and<00:04:13.170> not<00:04:13.320> that<00:04:13.500> easy<00:04:13.680> to<00:04:13.769> parse<00:04:14.010> and 00:04:14.479 --> 00:04:14.489 align:start position:0% low-level and not that easy to parse and 00:04:14.489 --> 00:04:16.400 align:start position:0% low-level and not that easy to parse and it<00:04:14.940> looks<00:04:15.090> a<00:04:15.180> bit<00:04:15.209> like<00:04:15.329> this<00:04:15.540> you<00:04:16.140> know<00:04:16.229> you<00:04:16.350> be 00:04:16.400 --> 00:04:16.410 align:start position:0% it looks a bit like this you know you be 00:04:16.410 --> 00:04:17.599 align:start position:0% it looks a bit like this you know you be able<00:04:16.500> to<00:04:16.590> read<00:04:16.680> it<00:04:16.799> but<00:04:17.220> it's<00:04:17.370> pretty 00:04:17.599 --> 00:04:17.609 align:start position:0% able to read it but it's pretty 00:04:17.609 --> 00:04:18.800 align:start position:0% able to read it but it's pretty complicated<00:04:17.940> and<00:04:18.269> this<00:04:18.390> is<00:04:18.539> actually<00:04:18.780> a 00:04:18.800 --> 00:04:18.810 align:start position:0% complicated and this is actually a 00:04:18.810 --> 00:04:20.509 align:start position:0% complicated and this is actually a simple<00:04:19.140> one<00:04:19.260> this<00:04:19.769> is<00:04:19.919> you<00:04:20.130> know<00:04:20.220> basically 00:04:20.509 --> 00:04:20.519 align:start position:0% simple one this is you know basically 00:04:20.519 --> 00:04:22.070 align:start position:0% simple one this is you know basically one<00:04:20.880> of<00:04:20.910> those<00:04:21.150> sends<00:04:21.510> where<00:04:21.660> I<00:04:21.690> showed<00:04:21.930> like 00:04:22.070 --> 00:04:22.080 align:start position:0% one of those sends where I showed like 00:04:22.080 --> 00:04:23.750 align:start position:0% one of those sends where I showed like ten<00:04:22.320> in<00:04:22.349> the<00:04:22.650> previous<00:04:22.950> slide<00:04:23.160> so<00:04:23.520> it<00:04:23.610> gets 00:04:23.750 --> 00:04:23.760 align:start position:0% ten in the previous slide so it gets 00:04:23.760 --> 00:04:25.430 align:start position:0% ten in the previous slide so it gets more<00:04:24.030> complicated<00:04:24.390> there's<00:04:24.780> a<00:04:24.840> lot<00:04:25.020> of<00:04:25.110> nuance 00:04:25.430 --> 00:04:25.440 align:start position:0% more complicated there's a lot of nuance 00:04:25.440 --> 00:04:27.560 align:start position:0% more complicated there's a lot of nuance here<00:04:25.530> but<00:04:26.490> if<00:04:26.580> we<00:04:26.700> started<00:04:27.030> to<00:04:27.210> think 00:04:27.560 --> 00:04:27.570 align:start position:0% here but if we started to think 00:04:27.570 --> 00:04:29.300 align:start position:0% here but if we started to think about<00:04:27.870> inspecting<00:04:28.560> these<00:04:28.680> and<00:04:28.920> seeing<00:04:29.130> what 00:04:29.300 --> 00:04:29.310 align:start position:0% about inspecting these and seeing what 00:04:29.310 --> 00:04:30.980 align:start position:0% about inspecting these and seeing what it<00:04:29.430> looks<00:04:29.580> like<00:04:29.760> if<00:04:30.240> you<00:04:30.330> zoom<00:04:30.570> in<00:04:30.690> you'll<00:04:30.840> see 00:04:30.980 --> 00:04:30.990 align:start position:0% it looks like if you zoom in you'll see 00:04:30.990 --> 00:04:32.600 align:start position:0% it looks like if you zoom in you'll see like<00:04:31.200> there's<00:04:31.410> a<00:04:31.470> from<00:04:31.770> and<00:04:31.980> a<00:04:32.010> gas<00:04:32.190> in<00:04:32.400> a<00:04:32.460> too 00:04:32.600 --> 00:04:32.610 align:start position:0% like there's a from and a gas in a too 00:04:32.610 --> 00:04:35.360 align:start position:0% like there's a from and a gas in a too similar<00:04:33.120> to<00:04:33.360> a<00:04:33.390> transaction<00:04:33.950> but<00:04:34.950> if<00:04:35.160> you<00:04:35.310> were 00:04:35.360 --> 00:04:35.370 align:start position:0% similar to a transaction but if you were 00:04:35.370 --> 00:04:37.090 align:start position:0% similar to a transaction but if you were to<00:04:35.490> take<00:04:35.640> it<00:04:35.820> and<00:04:35.970> just<00:04:36.000> treat<00:04:36.360> this<00:04:36.480> as<00:04:36.690> such 00:04:37.090 --> 00:04:37.100 align:start position:0% to take it and just treat this as such 00:04:37.100 --> 00:04:39.680 align:start position:0% to take it and just treat this as such you've<00:04:38.100> been<00:04:38.310> for<00:04:38.640> not<00:04:39.030> a<00:04:39.060> good<00:04:39.240> time 00:04:39.680 --> 00:04:39.690 align:start position:0% you've been for not a good time 00:04:39.690 --> 00:04:43.280 align:start position:0% you've been for not a good time and<00:04:40.500> so<00:04:41.460> we<00:04:41.970> refuse<00:04:42.570> examples<00:04:43.050> of<00:04:43.170> here 00:04:43.280 --> 00:04:43.290 align:start position:0% and so we refuse examples of here 00:04:43.290 --> 00:04:44.480 align:start position:0% and so we refuse examples of here different<00:04:43.500> types<00:04:43.800> of<00:04:43.980> problems<00:04:44.280> that<00:04:44.340> can 00:04:44.480 --> 00:04:44.490 align:start position:0% different types of problems that can 00:04:44.490 --> 00:04:46.820 align:start position:0% different types of problems that can happen<00:04:44.550> and<00:04:44.970> and<00:04:45.840> the<00:04:45.960> right<00:04:46.140> ways<00:04:46.320> to<00:04:46.560> sort<00:04:46.740> of 00:04:46.820 --> 00:04:46.830 align:start position:0% happen and and the right ways to sort of 00:04:46.830 --> 00:04:48.860 align:start position:0% happen and and the right ways to sort of handle<00:04:47.040> this<00:04:47.130> and<00:04:47.850> so<00:04:48.030> on<00:04:48.180> this<00:04:48.270> left<00:04:48.510> side<00:04:48.690> we 00:04:48.860 --> 00:04:48.870 align:start position:0% handle this and so on this left side we 00:04:48.870 --> 00:04:50.810 align:start position:0% handle this and so on this left side we have<00:04:49.020> what<00:04:49.770> we're<00:04:49.980> gonna<00:04:50.070> call<00:04:50.220> traces<00:04:50.670> here 00:04:50.810 --> 00:04:50.820 align:start position:0% have what we're gonna call traces here 00:04:50.820 --> 00:04:53.630 align:start position:0% have what we're gonna call traces here there's<00:04:51.390> different<00:04:51.480> types<00:04:51.810> of<00:04:51.960> calls<00:04:52.200> and<00:04:52.640> we 00:04:53.630 --> 00:04:53.640 align:start position:0% there's different types of calls and we 00:04:53.640 --> 00:04:56.030 align:start position:0% there's different types of calls and we see<00:04:53.790> one<00:04:54.000> we<00:04:54.030> send<00:04:54.390> Alice<00:04:54.660> one<00:04:54.840> eath<00:04:55.040> another 00:04:56.030 --> 00:04:56.040 align:start position:0% see one we send Alice one eath another 00:04:56.040 --> 00:04:57.800 align:start position:0% see one we send Alice one eath another to<00:04:56.280> Bob<00:04:56.430> and<00:04:56.760> if<00:04:56.820> we<00:04:56.940> just<00:04:57.240> turn<00:04:57.600> that<00:04:57.660> into 00:04:57.800 --> 00:04:57.810 align:start position:0% to Bob and if we just turn that into 00:04:57.810 --> 00:05:00.170 align:start position:0% to Bob and if we just turn that into credits<00:04:58.230> and<00:04:58.350> debits<00:04:58.500> accordingly<00:04:59.100> we<00:05:00.060> would 00:05:00.170 --> 00:05:00.180 align:start position:0% credits and debits accordingly we would 00:05:00.180 --> 00:05:03.050 align:start position:0% credits and debits accordingly we would do<00:05:00.330> that<00:05:00.480> and<00:05:01.010> the<00:05:02.010> issue<00:05:02.130> here<00:05:02.400> is<00:05:02.580> like<00:05:03.030> I 00:05:03.050 --> 00:05:03.060 align:start position:0% do that and the issue here is like I 00:05:03.060 --> 00:05:04.460 align:start position:0% do that and the issue here is like I presented<00:05:03.450> earlier<00:05:03.660> it<00:05:03.990> doesn't<00:05:04.320> actually 00:05:04.460 --> 00:05:04.470 align:start position:0% presented earlier it doesn't actually 00:05:04.470 --> 00:05:06.500 align:start position:0% presented earlier it doesn't actually happen<00:05:05.310> that<00:05:05.340> way<00:05:05.520> in<00:05:05.640> this<00:05:05.760> transaction<00:05:06.120> and 00:05:06.500 --> 00:05:06.510 align:start position:0% happen that way in this transaction and 00:05:06.510 --> 00:05:08.480 align:start position:0% happen that way in this transaction and it's<00:05:07.290> because<00:05:07.500> we're<00:05:07.620> missing<00:05:07.830> something<00:05:08.340> so 00:05:08.480 --> 00:05:08.490 align:start position:0% it's because we're missing something so 00:05:08.490 --> 00:05:09.890 align:start position:0% it's because we're missing something so not<00:05:08.700> everything's<00:05:09.090> gonna<00:05:09.240> be<00:05:09.420> on<00:05:09.540> the<00:05:09.660> slides 00:05:09.890 --> 00:05:09.900 align:start position:0% not everything's gonna be on the slides 00:05:09.900 --> 00:05:11.210 align:start position:0% not everything's gonna be on the slides here<00:05:10.140> and<00:05:10.380> we're<00:05:10.500> gonna<00:05:10.560> sort<00:05:10.860> of<00:05:10.890> bring<00:05:11.100> those 00:05:11.210 --> 00:05:11.220 align:start position:0% here and we're gonna sort of bring those 00:05:11.220 --> 00:05:13.340 align:start position:0% here and we're gonna sort of bring those in<00:05:11.400> over<00:05:11.640> time<00:05:11.850> and<00:05:12.090> so<00:05:12.600> in<00:05:12.720> this<00:05:12.810> case<00:05:12.870> what 00:05:13.340 --> 00:05:13.350 align:start position:0% in over time and so in this case what 00:05:13.350 --> 00:05:15.560 align:start position:0% in over time and so in this case what you<00:05:13.440> actually<00:05:13.740> need<00:05:13.830> to<00:05:13.860> look<00:05:14.130> at<00:05:14.370> is<00:05:14.760> this 00:05:15.560 --> 00:05:15.570 align:start position:0% you actually need to look at is this 00:05:15.570 --> 00:05:18.580 align:start position:0% you actually need to look at is this thing<00:05:15.810> called<00:05:16.080> the<00:05:17.270> transaction<00:05:18.270> status 00:05:18.580 --> 00:05:18.590 align:start position:0% thing called the transaction status 00:05:18.590 --> 00:05:21.260 align:start position:0% thing called the transaction status which<00:05:19.590> we'll<00:05:19.710> see<00:05:19.860> here<00:05:20.040> so<00:05:20.700> this<00:05:20.850> came<00:05:21.060> with 00:05:21.260 --> 00:05:21.270 align:start position:0% which we'll see here so this came with 00:05:21.270 --> 00:05:23.720 align:start position:0% which we'll see here so this came with an<00:05:21.480> upgrade<00:05:22.200> I<00:05:22.470> believe<00:05:22.740> last<00:05:22.950> year<00:05:23.190> I<00:05:23.490> think 00:05:23.720 --> 00:05:23.730 align:start position:0% an upgrade I believe last year I think 00:05:23.730 --> 00:05:25.580 align:start position:0% an upgrade I believe last year I think the<00:05:24.090> Byzantium<00:05:24.420> upgrade<00:05:24.930> they<00:05:25.290> added<00:05:25.500> this 00:05:25.580 --> 00:05:25.590 align:start position:0% the Byzantium upgrade they added this 00:05:25.590 --> 00:05:27.140 align:start position:0% the Byzantium upgrade they added this new<00:05:25.740> opcode<00:05:26.160> and<00:05:26.310> they<00:05:26.700> also<00:05:26.820> added<00:05:27.000> the 00:05:27.140 --> 00:05:27.150 align:start position:0% new opcode and they also added the 00:05:27.150 --> 00:05:28.190 align:start position:0% new opcode and they also added the status<00:05:27.540> to<00:05:27.720> this<00:05:27.810> thing<00:05:27.990> called<00:05:28.020> the 00:05:28.190 --> 00:05:28.200 align:start position:0% status to this thing called the 00:05:28.200 --> 00:05:30.440 align:start position:0% status to this thing called the transaction<00:05:28.770> receipt<00:05:28.920> and<00:05:29.310> so<00:05:30.000> when<00:05:30.420> a 00:05:30.440 --> 00:05:30.450 align:start position:0% transaction receipt and so when a 00:05:30.450 --> 00:05:32.630 align:start position:0% transaction receipt and so when a transactions<00:05:31.350> included<00:05:31.650> in<00:05:31.710> a<00:05:31.770> block<00:05:32.010> the 00:05:32.630 --> 00:05:32.640 align:start position:0% transactions included in a block the 00:05:32.640 --> 00:05:34.010 align:start position:0% transactions included in a block the blockchain<00:05:33.120> will<00:05:33.390> generate<00:05:33.690> this<00:05:33.870> thing 00:05:34.010 --> 00:05:34.020 align:start position:0% blockchain will generate this thing 00:05:34.020 --> 00:05:35.630 align:start position:0% blockchain will generate this thing called<00:05:34.200> a<00:05:34.260> receipt<00:05:34.530> which<00:05:34.740> tells<00:05:35.010> you<00:05:35.130> it's 00:05:35.630 --> 00:05:35.640 align:start position:0% called a receipt which tells you it's 00:05:35.640 --> 00:05:37.070 align:start position:0% called a receipt which tells you it's similar<00:05:35.880> like<00:05:36.000> a<00:05:36.210> store<00:05:36.420> receipt<00:05:36.720> it's<00:05:36.900> just 00:05:37.070 --> 00:05:37.080 align:start position:0% similar like a store receipt it's just 00:05:37.080 --> 00:05:38.600 align:start position:0% similar like a store receipt it's just you<00:05:37.170> know<00:05:37.260> here's<00:05:37.500> the<00:05:37.560> final<00:05:37.860> state<00:05:38.220> of<00:05:38.250> what 00:05:38.600 --> 00:05:38.610 align:start position:0% you know here's the final state of what 00:05:38.610 --> 00:05:40.550 align:start position:0% you know here's the final state of what happened<00:05:38.970> and<00:05:39.180> so<00:05:39.750> if<00:05:39.870> you<00:05:39.990> didn't<00:05:40.260> use<00:05:40.380> all 00:05:40.550 --> 00:05:40.560 align:start position:0% happened and so if you didn't use all 00:05:40.560 --> 00:05:42.740 align:start position:0% happened and so if you didn't use all the<00:05:40.710> gas<00:05:40.920> or<00:05:41.310> it<00:05:41.790> failed<00:05:42.060> for<00:05:42.210> some<00:05:42.450> reason 00:05:42.740 --> 00:05:42.750 align:start position:0% the gas or it failed for some reason 00:05:42.750 --> 00:05:44.240 align:start position:0% the gas or it failed for some reason that<00:05:43.020> kind<00:05:43.320> of<00:05:43.380> information<00:05:43.830> will<00:05:43.980> be<00:05:44.100> there 00:05:44.240 --> 00:05:44.250 align:start position:0% that kind of information will be there 00:05:44.250 --> 00:05:46.400 align:start position:0% that kind of information will be there and<00:05:44.520> so<00:05:45.420> in<00:05:45.540> this<00:05:45.630> case<00:05:45.840> we<00:05:46.020> see<00:05:46.170> it<00:05:46.260> the 00:05:46.400 --> 00:05:46.410 align:start position:0% and so in this case we see it the 00:05:46.410 --> 00:05:48.470 align:start position:0% and so in this case we see it the receipt<00:05:47.070> is<00:05:47.190> a<00:05:47.220> failure<00:05:47.520> and<00:05:47.820> so<00:05:48.000> what<00:05:48.390> that 00:05:48.470 --> 00:05:48.480 align:start position:0% receipt is a failure and so what that 00:05:48.480 --> 00:05:50.150 align:start position:0% receipt is a failure and so what that means<00:05:48.750> is<00:05:49.020> actually<00:05:49.320> none<00:05:49.500> of<00:05:49.590> the<00:05:49.710> transfers 00:05:50.150 --> 00:05:50.160 align:start position:0% means is actually none of the transfers 00:05:50.160 --> 00:05:51.470 align:start position:0% means is actually none of the transfers that<00:05:50.310> we<00:05:50.400> might<00:05:50.640> have<00:05:50.820> that<00:05:51.210> might<00:05:51.360> have 00:05:51.470 --> 00:05:51.480 align:start position:0% that we might have that might have 00:05:51.480 --> 00:05:53.420 align:start position:0% that we might have that might have happened<00:05:51.630> if<00:05:51.870> it<00:05:51.960> didn't<00:05:52.200> fail<00:05:52.350> can<00:05:53.160> actually 00:05:53.420 --> 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align:start position:0% see here that nobody received any and we're<00:05:59.670> good<00:06:00.210> to<00:06:00.240> go<00:06:01.520> so<00:06:02.520> for<00:06:02.640> example<00:06:02.730> -<00:06:03.200> this 00:06:04.190 --> 00:06:04.200 align:start position:0% we're good to go so for example - this 00:06:04.200 --> 00:06:06.770 align:start position:0% we're good to go so for example - this is<00:06:04.350> the<00:06:04.440> same<00:06:04.620> sort<00:06:04.890> of<00:06:04.980> scenario<00:06:05.220> here<00:06:05.780> except 00:06:06.770 --> 00:06:06.780 align:start position:0% is the same sort of scenario here except 00:06:06.780 --> 00:06:08.030 align:start position:0% is the same sort of scenario here except we<00:06:06.840> do<00:06:06.960> you<00:06:07.020> see<00:06:07.110> this<00:06:07.230> thing<00:06:07.290> that<00:06:07.590> says<00:06:07.650> fail 00:06:08.030 --> 00:06:08.040 align:start position:0% we do you see this thing that says fail 00:06:08.040 --> 00:06:10.340 align:start position:0% we do you see this thing that says fail on<00:06:08.280> one<00:06:08.520> of<00:06:08.550> these<00:06:08.700> calls<00:06:08.970> and<00:06:09.330> I<00:06:10.140> didn't 00:06:10.340 --> 00:06:10.350 align:start position:0% on one of these calls and I didn't 00:06:10.350 --> 00:06:11.900 align:start position:0% on one of these calls and I didn't really<00:06:10.500> describe<00:06:10.830> the<00:06:11.010> calls<00:06:11.220> yet<00:06:11.460> but<00:06:11.640> a<00:06:11.670> call 00:06:11.900 --> 00:06:11.910 align:start position:0% really describe the calls yet but a call 00:06:11.910 --> 00:06:14.630 align:start position:0% really describe the calls yet but a call is<00:06:12.090> this<00:06:12.510> sort<00:06:12.690> of<00:06:12.750> it's<00:06:13.260> this<00:06:13.440> type<00:06:13.980> of<00:06:14.220> a 00:06:14.630 --> 00:06:14.640 align:start position:0% is this sort of it's this type of a 00:06:14.640 --> 00:06:15.950 align:start position:0% is this sort of it's this type of a trace<00:06:15.000> there's<00:06:15.270> different<00:06:15.540> a<00:06:15.570> few<00:06:15.600> different 00:06:15.950 --> 00:06:15.960 align:start position:0% trace there's different a few different 00:06:15.960 --> 00:06:18.170 align:start position:0% trace there's different a few different types<00:06:16.050> and<00:06:16.410> so<00:06:16.980> these<00:06:17.190> sins<00:06:17.430> are<00:06:17.640> also<00:06:17.940> calls 00:06:18.170 --> 00:06:18.180 align:start position:0% types and so these sins are also calls 00:06:18.180 --> 00:06:19.940 align:start position:0% types and so these sins are also calls but<00:06:18.900> these<00:06:19.020> ones<00:06:19.140> are<00:06:19.290> other<00:06:19.470> ones<00:06:19.680> that<00:06:19.830> may 00:06:19.940 --> 00:06:19.950 align:start position:0% but these ones are other ones that may 00:06:19.950 --> 00:06:21.770 align:start position:0% but these ones are other ones that may just<00:06:20.100> like<00:06:20.280> call<00:06:20.700> some<00:06:20.910> function<00:06:21.060> to<00:06:21.540> you<00:06:21.690> know 00:06:21.770 --> 00:06:21.780 align:start position:0% just like call some function to you know 00:06:21.780 --> 00:06:23.780 align:start position:0% just like call some function to you know log<00:06:21.990> something<00:06:22.320> or<00:06:22.800> it's<00:06:23.340> that<00:06:23.670> doesn't 00:06:23.780 --> 00:06:23.790 align:start position:0% log something or it's that doesn't 00:06:23.790 --> 00:06:25.160 align:start position:0% log something or it's that doesn't actually<00:06:23.940> transfer<00:06:24.480> anything<00:06:24.750> anywhere<00:06:25.020> it's 00:06:25.160 --> 00:06:25.170 align:start position:0% actually transfer anything anywhere it's 00:06:25.170 --> 00:06:26.680 align:start position:0% actually transfer anything anywhere it's just<00:06:25.200> you<00:06:25.380> know<00:06:25.500> calling<00:06:25.770> a<00:06:25.830> contract<00:06:26.280> and<00:06:26.430> so 00:06:26.680 --> 00:06:26.690 align:start position:0% just you know calling a contract and so 00:06:26.690 --> 00:06:29.120 align:start position:0% just you know calling a contract and so generally<00:06:27.690> you<00:06:28.290> might<00:06:28.470> ignore<00:06:28.710> these<00:06:28.890> if<00:06:29.040> you 00:06:29.120 --> 00:06:29.130 align:start position:0% generally you might ignore these if you 00:06:29.130 --> 00:06:30.410 align:start position:0% generally you might ignore these if you just<00:06:29.280> care<00:06:29.460> about<00:06:29.490> sort<00:06:29.850> of<00:06:29.880> your<00:06:30.030> customers 00:06:30.410 --> 00:06:30.420 align:start position:0% just care about sort of your customers 00:06:30.420 --> 00:06:33.800 align:start position:0% just care about sort of your customers information<00:06:31.580> and<00:06:32.580> so<00:06:32.940> learning<00:06:33.390> what<00:06:33.630> we<00:06:33.690> just 00:06:33.800 --> 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align:start position:0% and we see it's a success so<00:06:38.669> we<00:06:39.120> credit<00:06:39.480> Alice<00:06:39.720> and<00:06:39.870> Bob 00:06:40.750 --> 00:06:40.760 align:start position:0% so we credit Alice and Bob 00:06:40.760 --> 00:06:43.520 align:start position:0% so we credit Alice and Bob and<00:06:41.760> if<00:06:41.970> if<00:06:42.210> you<00:06:42.420> sort<00:06:42.810> of<00:06:42.900> caught<00:06:43.080> on<00:06:43.110> from<00:06:43.440> the 00:06:43.520 --> 00:06:43.530 align:start position:0% and if if you sort of caught on from the 00:06:43.530 --> 00:06:44.990 align:start position:0% and if if you sort of caught on from the previous<00:06:43.830> example<00:06:44.250> that<00:06:44.730> didn't<00:06:44.940> actually 00:06:44.990 --> 00:06:45.000 align:start position:0% previous example that didn't actually 00:06:45.000 --> 00:06:47.150 align:start position:0% previous example that didn't actually happen<00:06:45.330> but<00:06:46.260> what's<00:06:46.620> interesting<00:06:46.710> about<00:06:46.950> this 00:06:47.150 --> 00:06:47.160 align:start position:0% happen but what's interesting about this 00:06:47.160 --> 00:06:48.470 align:start position:0% happen but what's interesting about this scenario<00:06:47.340> is<00:06:47.730> it's<00:06:47.910> not<00:06:48.000> that<00:06:48.060> nobody 00:06:48.470 --> 00:06:48.480 align:start position:0% scenario is it's not that nobody 00:06:48.480 --> 00:06:51.650 align:start position:0% scenario is it's not that nobody received<00:06:49.140> any<00:06:49.290> it's<00:06:49.860> that<00:06:50.010> only<00:06:50.220> some<00:06:50.670> did<00:06:50.880> so 00:06:51.650 --> 00:06:51.660 align:start position:0% received any it's that only some did so 00:06:51.660 --> 00:06:53.360 align:start position:0% received any it's that only some did so this<00:06:51.870> transaction<00:06:52.290> receipt<00:06:52.560> status<00:06:53.070> doesn't 00:06:53.360 --> 00:06:53.370 align:start position:0% this transaction receipt status doesn't 00:06:53.370 --> 00:06:54.410 align:start position:0% this transaction receipt status doesn't tell<00:06:53.490> you<00:06:53.580> everything<00:06:53.730> there's<00:06:54.330> this 00:06:54.410 --> 00:06:54.420 align:start position:0% tell you everything there's this 00:06:54.420 --> 00:06:56.480 align:start position:0% tell you everything there's this possibility<00:06:54.600> of<00:06:55.080> like<00:06:55.260> a<00:06:55.290> full<00:06:55.710> failure<00:06:56.250> where 00:06:56.480 --> 00:06:56.490 align:start position:0% possibility of like a full failure where 00:06:56.490 --> 00:06:58.340 align:start position:0% possibility of like a full failure where the<00:06:56.580> transaction<00:06:57.090> receipt<00:06:57.330> is<00:06:57.450> a<00:06:57.480> failure<00:06:57.720> but 00:06:58.340 --> 00:06:58.350 align:start position:0% the transaction receipt is a failure but 00:06:58.350 --> 00:06:59.750 align:start position:0% the transaction receipt is a failure but there's<00:06:58.530> this<00:06:58.590> partial<00:06:59.100> failure<00:06:59.400> states<00:06:59.640> as 00:06:59.750 --> 00:06:59.760 align:start position:0% there's this partial failure states as 00:06:59.760 --> 00:07:01.670 align:start position:0% there's this partial failure states as well<00:06:59.940> and<00:07:00.300> these<00:07:00.750> can<00:07:00.930> get<00:07:01.050> more<00:07:01.290> complicated 00:07:01.670 --> 00:07:01.680 align:start position:0% well and these can get more complicated 00:07:01.680 --> 00:07:04.310 align:start position:0% well and these can get more complicated than<00:07:02.040> this<00:07:02.190> and<00:07:02.640> so<00:07:02.940> in<00:07:03.150> this<00:07:03.240> example<00:07:03.420> what<00:07:04.230> we 00:07:04.310 --> 00:07:04.320 align:start position:0% than this and so in this example what we 00:07:04.320 --> 00:07:05.570 align:start position:0% than this and so in this example what we really<00:07:04.680> needed<00:07:04.890> to<00:07:04.980> do<00:07:05.130> when<00:07:05.340> we're<00:07:05.490> looking 00:07:05.570 --> 00:07:05.580 align:start position:0% really needed to do when we're looking 00:07:05.580 --> 00:07:07.820 align:start position:0% really needed to do when we're looking at<00:07:05.820> these<00:07:05.910> traces<00:07:06.360> its<00:07:07.200> turned<00:07:07.500> it<00:07:07.620> into<00:07:07.740> a 00:07:07.820 --> 00:07:07.830 align:start position:0% at these traces its turned it into a 00:07:07.830 --> 00:07:10.730 align:start position:0% at these traces its turned it into a tree<00:07:08.160> so<00:07:08.630> it's<00:07:09.630> actually<00:07:09.750> if<00:07:10.080> we<00:07:10.290> can<00:07:10.410> see<00:07:10.530> this 00:07:10.730 --> 00:07:10.740 align:start position:0% tree so it's actually if we can see this 00:07:10.740 --> 00:07:12.290 align:start position:0% tree so it's actually if we can see this like<00:07:10.920> hierarchy<00:07:11.370> here<00:07:11.520> we<00:07:11.640> have<00:07:11.760> this<00:07:11.850> call<00:07:12.150> at 00:07:12.290 --> 00:07:12.300 align:start position:0% like hierarchy here we have this call at 00:07:12.300 --> 00:07:14.659 align:start position:0% like hierarchy here we have this call at the<00:07:12.390> root<00:07:12.570> and<00:07:12.750> then<00:07:13.230> we<00:07:13.260> have<00:07:13.530> you<00:07:14.280> know<00:07:14.370> Alice 00:07:14.659 --> 00:07:14.669 align:start position:0% the root and then we have you know Alice 00:07:14.669 --> 00:07:16.190 align:start position:0% the root and then we have you know Alice receives<00:07:14.850> one<00:07:15.150> and<00:07:15.360> then<00:07:15.450> a<00:07:15.540> few<00:07:15.690> nested<00:07:16.020> calls 00:07:16.190 --> 00:07:16.200 align:start position:0% receives one and then a few nested calls 00:07:16.200 --> 00:07:17.900 align:start position:0% receives one and then a few nested calls and<00:07:16.500> then<00:07:16.590> one<00:07:16.740> of<00:07:16.830> them<00:07:16.919> is<00:07:17.040> a<00:07:17.070> failure<00:07:17.370> and 00:07:17.900 --> 00:07:17.910 align:start position:0% and then one of them is a failure and 00:07:17.910 --> 00:07:19.370 align:start position:0% and then one of them is a failure and what<00:07:18.060> this<00:07:18.150> looks<00:07:18.419> like<00:07:18.540> in<00:07:18.840> the<00:07:18.930> trace<00:07:19.200> is 00:07:19.370 --> 00:07:19.380 align:start position:0% what this looks like in the trace is 00:07:19.380 --> 00:07:20.330 align:start position:0% what this looks like in the trace is there's<00:07:19.530> this<00:07:19.620> thing<00:07:19.830> called<00:07:19.860> there's<00:07:20.250> an 00:07:20.330 --> 00:07:20.340 align:start position:0% there's this thing called there's an 00:07:20.340 --> 00:07:22.790 align:start position:0% there's this thing called there's an error<00:07:20.520> on<00:07:20.790> it<00:07:20.940> and<00:07:21.110> if<00:07:22.110> it<00:07:22.290> has<00:07:22.380> an<00:07:22.500> error<00:07:22.680> that 00:07:22.790 --> 00:07:22.800 align:start position:0% error on it and if it has an error that 00:07:22.800 --> 00:07:24.680 align:start position:0% error on it and if it has an error that means<00:07:23.010> it<00:07:23.190> failed<00:07:23.430> and<00:07:23.669> so<00:07:24.120> when<00:07:24.360> you<00:07:24.450> put<00:07:24.600> it 00:07:24.680 --> 00:07:24.690 align:start position:0% means it failed and so when you put it 00:07:24.690 --> 00:07:26.510 align:start position:0% means it failed and so when you put it into<00:07:24.810> this<00:07:24.960> tree<00:07:25.230> format<00:07:25.620> you<00:07:26.100> can<00:07:26.250> see<00:07:26.430> that 00:07:26.510 --> 00:07:26.520 align:start position:0% into this tree format you can see that 00:07:26.520 --> 00:07:28.250 align:start position:0% into this tree format you can see that the<00:07:26.640> sender<00:07:27.000> Bob<00:07:27.150> is<00:07:27.300> actually<00:07:27.570> within<00:07:27.750> that 00:07:28.250 --> 00:07:28.260 align:start position:0% the sender Bob is actually within that 00:07:28.260 --> 00:07:30.230 align:start position:0% the sender Bob is actually within that part<00:07:28.590> of<00:07:28.740> the<00:07:28.860> tree<00:07:29.100> and<00:07:29.760> when<00:07:29.910> it's<00:07:30.030> there 00:07:30.230 --> 00:07:30.240 align:start position:0% part of the tree and when it's there 00:07:30.240 --> 00:07:31.580 align:start position:0% part of the tree and when it's there what<00:07:30.419> that<00:07:30.690> means<00:07:30.900> is<00:07:31.050> that<00:07:31.169> that<00:07:31.320> doesn't 00:07:31.580 --> 00:07:31.590 align:start position:0% what that means is that that doesn't 00:07:31.590 --> 00:07:33.470 align:start position:0% what that means is that that doesn't actually<00:07:31.860> happen<00:07:32.220> and<00:07:32.610> you<00:07:32.669> shouldn't<00:07:33.000> create 00:07:33.470 --> 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align:start position:0% good to go so the last example here 00:07:42.350 --> 00:07:45.050 align:start position:0% good to go so the last example here looks<00:07:43.350> entirely<00:07:44.100> the<00:07:44.370> same<00:07:44.550> as<00:07:44.729> the<00:07:44.820> former 00:07:45.050 --> 00:07:45.060 align:start position:0% looks entirely the same as the former 00:07:45.060 --> 00:07:48.770 align:start position:0% looks entirely the same as the former one<00:07:45.770> so<00:07:46.770> there's<00:07:46.979> even<00:07:47.100> more<00:07:47.220> here<00:07:47.970> to<00:07:48.300> kind<00:07:48.750> of 00:07:48.770 --> 00:07:48.780 align:start position:0% one so there's even more here to kind of 00:07:48.780 --> 00:07:50.420 align:start position:0% one so there's even more here to kind of a<00:07:48.870> look<00:07:48.960> at<00:07:49.110> and<00:07:49.590> so<00:07:49.770> in<00:07:49.830> this<00:07:49.890> example<00:07:49.979> if<00:07:50.310> we 00:07:50.420 --> 00:07:50.430 align:start position:0% a look at and so in this example if we 00:07:50.430 --> 00:07:52.610 align:start position:0% a look at and so in this example if we did<00:07:50.580> the<00:07:50.700> same<00:07:50.850> thing<00:07:51.210> we<00:07:51.600> credit<00:07:51.990> Alice<00:07:52.320> and 00:07:52.610 --> 00:07:52.620 align:start position:0% did the same thing we credit Alice and 00:07:52.620 --> 00:07:55.940 align:start position:0% did the same thing we credit Alice and then<00:07:53.550> that's<00:07:53.760> wrong<00:07:54.000> and<00:07:54.810> in<00:07:55.560> this<00:07:55.710> time 00:07:55.940 --> 00:07:55.950 align:start position:0% then that's wrong and in this time 00:07:55.950 --> 00:07:59.390 align:start position:0% then that's wrong and in this time nobody<00:07:56.880> should<00:07:57.270> receive<00:07:57.540> anything<00:07:57.750> and<00:07:58.530> so 00:07:59.390 --> 00:07:59.400 align:start position:0% nobody should receive anything and so 00:07:59.400 --> 00:08:01.100 align:start position:0% nobody should receive anything and so there's<00:07:59.580> another<00:07:59.640> thing<00:07:59.940> missing<00:08:00.270> here<00:08:00.419> so 00:08:01.100 --> 00:08:01.110 align:start position:0% there's another thing missing here so 00:08:01.110 --> 00:08:02.390 align:start position:0% there's another thing missing here so when<00:08:01.260> we<00:08:01.320> look<00:08:01.500> at<00:08:01.530> these<00:08:01.680> calls<00:08:01.950> there's 00:08:02.390 --> 00:08:02.400 align:start position:0% when we look at these calls there's 00:08:02.400 --> 00:08:03.680 align:start position:0% when we look at these calls there's different<00:08:02.669> types<00:08:02.940> of<00:08:03.150> calls<00:08:03.360> there's<00:08:03.570> not 00:08:03.680 --> 00:08:03.690 align:start position:0% different types of calls there's not 00:08:03.690 --> 00:08:05.780 align:start position:0% different types of calls there's not just<00:08:03.720> one<00:08:03.900> there's<00:08:04.890> all<00:08:05.340> sorts<00:08:05.580> of<00:08:05.640> different 00:08:05.780 --> 00:08:05.790 align:start position:0% just one there's all sorts of different 00:08:05.790 --> 00:08:07.610 align:start position:0% just one there's all sorts of different ones<00:08:06.030> but<00:08:06.270> in<00:08:06.810> particular<00:08:07.169> in<00:08:07.260> this<00:08:07.350> example 00:08:07.610 --> 00:08:07.620 align:start position:0% ones but in particular in this example 00:08:07.620 --> 00:08:13.100 align:start position:0% ones but in particular in this example I'm<00:08:08.130> using<00:08:08.280> one<00:08:08.669> called<00:08:09.330> a<00:08:10.880> delegate<00:08:11.880> call<00:08:12.110> so 00:08:13.100 --> 00:08:13.110 align:start position:0% I'm using one called a delegate call so 00:08:13.110 --> 00:08:15.740 align:start position:0% I'm using one called a delegate call so we<00:08:13.800> need<00:08:13.979> to<00:08:14.100> pick<00:08:14.729> out<00:08:14.910> the<00:08:15.030> specific<00:08:15.510> types 00:08:15.740 --> 00:08:15.750 align:start position:0% we need to pick out the specific types 00:08:15.750 --> 00:08:17.810 align:start position:0% we need to pick out the specific types of<00:08:15.960> calls<00:08:16.200> that<00:08:16.470> can<00:08:16.590> actually<00:08:16.820> transfer 00:08:17.810 --> 00:08:17.820 align:start position:0% of calls that can actually transfer 00:08:17.820 --> 00:08:20.150 align:start position:0% of calls that can actually transfer theorem<00:08:18.180> around<00:08:18.419> and<00:08:19.260> sort<00:08:19.560> of<00:08:19.620> either<00:08:19.890> ignore 00:08:20.150 --> 00:08:20.160 align:start position:0% theorem around and sort of either ignore 00:08:20.160 --> 00:08:21.530 align:start position:0% theorem around and sort of either ignore the<00:08:20.280> other<00:08:20.400> ones<00:08:20.580> or<00:08:20.729> treat<00:08:21.000> them<00:08:21.120> differently 00:08:21.530 --> 00:08:21.540 align:start position:0% the other ones or treat them differently 00:08:21.540 --> 00:08:23.290 align:start position:0% the other ones or treat them differently and<00:08:21.750> so<00:08:22.260> in<00:08:22.320> this<00:08:22.380> case<00:08:22.560> a<00:08:22.590> delegate<00:08:23.040> call 00:08:23.290 --> 00:08:23.300 align:start position:0% and so in this case a delegate call 00:08:23.300 --> 00:08:25.460 align:start position:0% and so in this case a delegate call without<00:08:24.300> going<00:08:24.450> to<00:08:24.570> sort<00:08:24.720> of<00:08:24.780> details<00:08:25.080> of<00:08:25.229> what 00:08:25.460 --> 00:08:25.470 align:start position:0% without going to sort of details of what 00:08:25.470 --> 00:08:27.440 align:start position:0% without going to sort of details of what exactly<00:08:25.890> it<00:08:25.979> does<00:08:26.010> it<00:08:26.490> looks<00:08:26.520> identical<00:08:26.910> to 00:08:27.440 --> 00:08:27.450 align:start position:0% exactly it does it looks identical to 00:08:27.450 --> 00:08:29.420 align:start position:0% exactly it does it looks identical to just<00:08:28.050> sending<00:08:28.290> aetherium<00:08:28.590> somewhere<00:08:28.979> except 00:08:29.420 --> 00:08:29.430 align:start position:0% just sending aetherium somewhere except 00:08:29.430 --> 00:08:32.000 align:start position:0% just sending aetherium somewhere except it<00:08:29.550> doesn't<00:08:30.030> actually<00:08:30.120> do<00:08:30.450> that<00:08:30.600> and<00:08:31.350> so<00:08:31.890> in 00:08:32.000 --> 00:08:32.010 align:start position:0% it doesn't actually do that and so in 00:08:32.010 --> 00:08:34.520 align:start position:0% it doesn't actually do that and so in this<00:08:32.070> example<00:08:32.219> when<00:08:33.120> we<00:08:33.240> account<00:08:33.419> for<00:08:33.539> that<00:08:33.719> we 00:08:34.520 --> 00:08:34.530 align:start position:0% this example when we account for that we 00:08:34.530 --> 00:08:39.320 align:start position:0% this example when we account for that we do<00:08:34.680> see<00:08:34.860> that<00:08:35.150> nothing<00:08:36.150> happens<00:08:38.060> so<00:08:39.060> that<00:08:39.089> was 00:08:39.320 --> 00:08:39.330 align:start position:0% do see that nothing happens so that was 00:08:39.330 --> 00:08:41.060 align:start position:0% do see that nothing happens so that was a<00:08:39.360> little<00:08:39.539> bit<00:08:39.690> like<00:08:39.900> how<00:08:40.110> to<00:08:40.169> handle<00:08:40.919> these 00:08:41.060 --> 00:08:41.070 align:start position:0% a little bit like how to handle these 00:08:41.070 --> 00:08:43.100 align:start position:0% a little bit like how to handle these and<00:08:41.820> it's<00:08:41.940> a<00:08:42.000> tricky<00:08:42.270> thing<00:08:42.300> and<00:08:42.780> it<00:08:42.900> could<00:08:43.020> get 00:08:43.100 --> 00:08:43.110 align:start position:0% and it's a tricky thing and it could get 00:08:43.110 --> 00:08:44.300 align:start position:0% and it's a tricky thing and it could get more<00:08:43.289> complicated<00:08:43.770> in<00:08:43.830> the<00:08:43.890> future<00:08:44.099> that's 00:08:44.300 --> 00:08:44.310 align:start position:0% more complicated in the future that's 00:08:44.310 --> 00:08:45.920 align:start position:0% more complicated in the future that's like<00:08:44.520> it's<00:08:44.730> a<00:08:44.850> day<00:08:45.030> but<00:08:45.420> a<00:08:45.450> lot<00:08:45.660> of<00:08:45.780> really 00:08:45.920 --> 00:08:45.930 align:start position:0% like it's a day but a lot of really 00:08:45.930 --> 00:08:47.450 align:start position:0% like it's a day but a lot of really clever<00:08:46.170> things<00:08:46.500> are<00:08:46.710> happening<00:08:47.160> a<00:08:47.220> lot<00:08:47.339> of 00:08:47.450 --> 00:08:47.460 align:start position:0% clever things are happening a lot of 00:08:47.460 --> 00:08:49.190 align:start position:0% clever things are happening a lot of cool<00:08:47.580> stuff<00:08:47.610> people<00:08:47.970> want<00:08:48.210> to<00:08:48.270> work<00:08:48.390> on<00:08:48.570> and 00:08:49.190 --> 00:08:49.200 align:start position:0% cool stuff people want to work on and 00:08:49.200 --> 00:08:50.600 align:start position:0% cool stuff people want to work on and it's<00:08:49.470> really<00:08:49.620> hard<00:08:49.740> to<00:08:49.860> get<00:08:49.950> this<00:08:50.040> right<00:08:50.370> and 00:08:50.600 --> 00:08:50.610 align:start position:0% it's really hard to get this right and 00:08:50.610 --> 00:08:51.980 align:start position:0% it's really hard to get this right and these<00:08:50.850> things<00:08:50.970> aren't<00:08:51.209> that<00:08:51.330> documented 00:08:51.980 --> 00:08:51.990 align:start position:0% these things aren't that documented 00:08:51.990 --> 00:08:53.070 align:start position:0% these things aren't that documented either 00:08:53.070 --> 00:08:53.080 align:start position:0% either 00:08:53.080 --> 00:08:55.259 align:start position:0% either and<00:08:53.380> so<00:08:53.920> we<00:08:54.580> got<00:08:54.760> to<00:08:54.850> figure<00:08:54.940> out<00:08:55.029> a<00:08:55.089> way<00:08:55.240> that 00:08:55.259 --> 00:08:55.269 align:start position:0% and so we got to figure out a way that 00:08:55.269 --> 00:08:57.150 align:start position:0% and so we got to figure out a way that even<00:08:55.720> if<00:08:55.810> we<00:08:55.930> don't<00:08:56.140> know<00:08:56.410> the<00:08:56.589> answer<00:08:56.860> how<00:08:57.100> do 00:08:57.150 --> 00:08:57.160 align:start position:0% even if we don't know the answer how do 00:08:57.160 --> 00:08:59.610 align:start position:0% even if we don't know the answer how do we<00:08:57.339> sort<00:08:57.550> of<00:08:57.700> make<00:08:58.660> sure<00:08:58.870> we're<00:08:59.080> not<00:08:59.110> exposing 00:08:59.610 --> 00:08:59.620 align:start position:0% we sort of make sure we're not exposing 00:08:59.620 --> 00:09:00.990 align:start position:0% we sort of make sure we're not exposing ourselves<00:08:59.830> to<00:09:00.010> these<00:09:00.130> issues<00:09:00.250> because<00:09:00.730> if 00:09:00.990 --> 00:09:01.000 align:start position:0% ourselves to these issues because if 00:09:01.000 --> 00:09:02.639 align:start position:0% ourselves to these issues because if you've<00:09:01.480> been<00:09:01.510> at<00:09:01.779> many<00:09:02.080> of<00:09:02.200> the<00:09:02.320> talks<00:09:02.500> today 00:09:02.639 --> 00:09:02.649 align:start position:0% you've been at many of the talks today 00:09:02.649 --> 00:09:04.050 align:start position:0% you've been at many of the talks today so<00:09:03.010> many<00:09:03.220> of<00:09:03.399> them<00:09:03.550> are<00:09:03.760> based<00:09:03.880> around 00:09:04.050 --> 00:09:04.060 align:start position:0% so many of them are based around 00:09:04.060 --> 00:09:06.150 align:start position:0% so many of them are based around contracts<00:09:04.600> right<00:09:04.959> identity<00:09:05.170> and<00:09:05.800> all<00:09:05.920> sorts 00:09:06.150 --> 00:09:06.160 align:start position:0% contracts right identity and all sorts 00:09:06.160 --> 00:09:07.440 align:start position:0% contracts right identity and all sorts of<00:09:06.220> things<00:09:06.339> are<00:09:06.519> just<00:09:06.580> contracts<00:09:07.180> ending 00:09:07.440 --> 00:09:07.450 align:start position:0% of things are just contracts ending 00:09:07.450 --> 00:09:09.030 align:start position:0% of things are just contracts ending everywhere<00:09:07.839> and<00:09:08.050> so<00:09:08.110> you<00:09:08.170> have<00:09:08.470> to<00:09:08.620> be<00:09:08.740> able<00:09:08.830> to 00:09:09.030 --> 00:09:09.040 align:start position:0% everywhere and so you have to be able to 00:09:09.040 --> 00:09:10.920 align:start position:0% everywhere and so you have to be able to support<00:09:09.370> these<00:09:09.550> but<00:09:10.060> many<00:09:10.240> exchanges<00:09:10.510> are 00:09:10.920 --> 00:09:10.930 align:start position:0% support these but many exchanges are 00:09:10.930 --> 00:09:12.540 align:start position:0% support these but many exchanges are many<00:09:11.050> wall<00:09:11.230> to<00:09:11.440> don't<00:09:11.649> because<00:09:12.339> of<00:09:12.370> the 00:09:12.540 --> 00:09:12.550 align:start position:0% many wall to don't because of the 00:09:12.550 --> 00:09:14.519 align:start position:0% many wall to don't because of the complexity<00:09:13.089> around<00:09:13.240> this<00:09:13.420> and<00:09:13.630> because<00:09:14.500> of 00:09:14.519 --> 00:09:14.529 align:start position:0% complexity around this and because of 00:09:14.529 --> 00:09:16.829 align:start position:0% complexity around this and because of the<00:09:14.709> risk<00:09:14.890> in<00:09:15.070> particular<00:09:15.490> to<00:09:15.610> exchanges<00:09:16.089> of 00:09:16.829 --> 00:09:16.839 align:start position:0% the risk in particular to exchanges of 00:09:16.839 --> 00:09:18.210 align:start position:0% the risk in particular to exchanges of getting<00:09:17.230> like<00:09:17.350> hacked<00:09:17.560> and<00:09:17.709> actually<00:09:17.920> losing 00:09:18.210 --> 00:09:18.220 align:start position:0% getting like hacked and actually losing 00:09:18.220 --> 00:09:21.210 align:start position:0% getting like hacked and actually losing money<00:09:18.370> and<00:09:19.089> so<00:09:19.720> the<00:09:20.079> kind<00:09:20.260> of<00:09:20.350> answer<00:09:20.740> here<00:09:21.070> is 00:09:21.210 --> 00:09:21.220 align:start position:0% money and so the kind of answer here is 00:09:21.220 --> 00:09:22.800 align:start position:0% money and so the kind of answer here is this<00:09:21.399> type<00:09:21.700> of<00:09:21.820> sort<00:09:22.120> of<00:09:22.149> detection<00:09:22.540> and 00:09:22.800 --> 00:09:22.810 align:start position:0% this type of sort of detection and 00:09:22.810 --> 00:09:25.319 align:start position:0% this type of sort of detection and response<00:09:23.399> and<00:09:24.399> the<00:09:24.610> first<00:09:24.790> step<00:09:25.029> of<00:09:25.120> that<00:09:25.180> is 00:09:25.319 --> 00:09:25.329 align:start position:0% response and the first step of that is 00:09:25.329 --> 00:09:27.509 align:start position:0% response and the first step of that is just<00:09:25.750> acknowledging<00:09:26.470> that<00:09:26.709> you<00:09:26.950> don't<00:09:27.250> know 00:09:27.509 --> 00:09:27.519 align:start position:0% just acknowledging that you don't know 00:09:27.519 --> 00:09:28.139 align:start position:0% just acknowledging that you don't know everything 00:09:28.139 --> 00:09:28.149 align:start position:0% everything 00:09:28.149 --> 00:09:29.519 align:start position:0% everything things<00:09:28.720> are<00:09:28.810> gonna<00:09:28.899> change<00:09:29.019> and<00:09:29.470> especially 00:09:29.519 --> 00:09:29.529 align:start position:0% things are gonna change and especially 00:09:29.529 --> 00:09:31.079 align:start position:0% things are gonna change and especially if<00:09:30.130> you're<00:09:30.310> working<00:09:30.370> with<00:09:30.490> multiple<00:09:30.700> block 00:09:31.079 --> 00:09:31.089 align:start position:0% if you're working with multiple block 00:09:31.089 --> 00:09:32.730 align:start position:0% if you're working with multiple block chains<00:09:31.390> and<00:09:31.600> multiple<00:09:31.930> currencies<00:09:32.260> that<00:09:32.290> kind 00:09:32.730 --> 00:09:32.740 align:start position:0% chains and multiple currencies that kind 00:09:32.740 --> 00:09:34.199 align:start position:0% chains and multiple currencies that kind of<00:09:32.769> stuff<00:09:32.920> it's<00:09:33.070> just<00:09:33.130> some<00:09:33.820> of<00:09:33.910> its<00:09:34.029> going<00:09:34.149> to 00:09:34.199 --> 00:09:34.209 align:start position:0% of stuff it's just some of its going to 00:09:34.209 --> 00:09:36.150 align:start position:0% of stuff it's just some of its going to slip<00:09:34.420> by<00:09:34.570> some<00:09:35.110> little<00:09:35.470> note<00:09:35.709> and<00:09:35.890> release 00:09:36.150 --> 00:09:36.160 align:start position:0% slip by some little note and release 00:09:36.160 --> 00:09:37.530 align:start position:0% slip by some little note and release notes<00:09:36.370> of<00:09:36.519> some<00:09:36.670> upgrade<00:09:37.000> of<00:09:37.149> your<00:09:37.269> software 00:09:37.530 --> 00:09:37.540 align:start position:0% notes of some upgrade of your software 00:09:37.540 --> 00:09:39.420 align:start position:0% notes of some upgrade of your software is<00:09:37.750> going<00:09:37.899> to<00:09:38.050> change<00:09:38.290> something<00:09:38.529> and<00:09:38.920> you<00:09:39.339> may 00:09:39.420 --> 00:09:39.430 align:start position:0% is going to change something and you may 00:09:39.430 --> 00:09:41.250 align:start position:0% is going to change something and you may not<00:09:39.579> realize<00:09:39.850> it<00:09:40.029> and<00:09:40.209> so<00:09:40.660> you<00:09:40.899> just<00:09:41.079> want<00:09:41.200> to 00:09:41.250 --> 00:09:41.260 align:start position:0% not realize it and so you just want to 00:09:41.260 --> 00:09:43.199 align:start position:0% not realize it and so you just want to take<00:09:42.070> a<00:09:42.100> step<00:09:42.339> back<00:09:42.519> and<00:09:42.700> say<00:09:42.790> you<00:09:42.850> know<00:09:43.000> I 00:09:43.199 --> 00:09:43.209 align:start position:0% take a step back and say you know I 00:09:43.209 --> 00:09:44.759 align:start position:0% take a step back and say you know I might<00:09:43.630> not<00:09:43.720> know<00:09:43.870> everything<00:09:44.260> if<00:09:44.410> you<00:09:44.620> don't 00:09:44.759 --> 00:09:44.769 align:start position:0% might not know everything if you don't 00:09:44.769 --> 00:09:46.980 align:start position:0% might not know everything if you don't well<00:09:45.220> like<00:09:45.550> how<00:09:45.730> do<00:09:45.790> you<00:09:45.940> do<00:09:46.420> this<00:09:46.600> like<00:09:46.810> how<00:09:46.930> do 00:09:46.980 --> 00:09:46.990 align:start position:0% well like how do you do this like how do 00:09:46.990 --> 00:09:50.009 align:start position:0% well like how do you do this like how do you<00:09:47.110> make<00:09:47.230> an<00:09:47.350> answer<00:09:47.589> here<00:09:47.769> and<00:09:48.100> so<00:09:48.910> one<00:09:49.870> way 00:09:50.009 --> 00:09:50.019 align:start position:0% you make an answer here and so one way 00:09:50.019 --> 00:09:51.329 align:start position:0% you make an answer here and so one way to<00:09:50.050> do<00:09:50.260> this<00:09:50.380> is<00:09:50.589> sort<00:09:50.740> of<00:09:50.769> cross-check<00:09:51.310> your 00:09:51.329 --> 00:09:51.339 align:start position:0% to do this is sort of cross-check your 00:09:51.339 --> 00:09:52.710 align:start position:0% to do this is sort of cross-check your data<00:09:51.640> right<00:09:52.120> there's<00:09:52.300> a<00:09:52.360> lot<00:09:52.510> of<00:09:52.630> people 00:09:52.710 --> 00:09:52.720 align:start position:0% data right there's a lot of people 00:09:52.720 --> 00:09:54.060 align:start position:0% data right there's a lot of people building<00:09:53.050> there's<00:09:53.380> a<00:09:53.440> lot<00:09:53.560> of<00:09:53.649> people<00:09:53.860> you<00:09:53.950> can 00:09:54.060 --> 00:09:54.070 align:start position:0% building there's a lot of people you can 00:09:54.070 --> 00:09:55.889 align:start position:0% building there's a lot of people you can talk<00:09:54.250> to<00:09:54.370> you<00:09:54.430> about<00:09:54.459> this<00:09:54.730> but<00:09:55.000> really<00:09:55.269> if<00:09:55.779> you 00:09:55.889 --> 00:09:55.899 align:start position:0% talk to you about this but really if you 00:09:55.899 --> 00:09:57.150 align:start position:0% talk to you about this but really if you can<00:09:56.019> automate<00:09:56.380> this<00:09:56.560> that's<00:09:56.800> sort<00:09:57.010> of<00:09:57.040> the 00:09:57.150 --> 00:09:57.160 align:start position:0% can automate this that's sort of the 00:09:57.160 --> 00:09:58.920 align:start position:0% can automate this that's sort of the ideal<00:09:57.430> here<00:09:57.730> if<00:09:58.060> you<00:09:58.209> can<00:09:58.329> cross-check<00:09:58.570> your 00:09:58.920 --> 00:09:58.930 align:start position:0% ideal here if you can cross-check your 00:09:58.930 --> 00:10:00.360 align:start position:0% ideal here if you can cross-check your data<00:09:59.110> and<00:09:59.290> say<00:09:59.410> oh<00:09:59.440> well<00:09:59.860> I<00:09:59.890> think<00:10:00.250> this 00:10:00.360 --> 00:10:00.370 align:start position:0% data and say oh well I think this 00:10:00.370 --> 00:10:01.980 align:start position:0% data and say oh well I think this happened<00:10:00.760> and<00:10:00.940> then<00:10:01.360> this<00:10:01.420> other<00:10:01.630> thing<00:10:01.810> says 00:10:01.980 --> 00:10:01.990 align:start position:0% happened and then this other thing says 00:10:01.990 --> 00:10:03.480 align:start position:0% happened and then this other thing says it<00:10:02.020> doesn't<00:10:02.500> and<00:10:02.649> it's<00:10:02.740> a<00:10:02.800> source<00:10:03.010> you<00:10:03.070> trust 00:10:03.480 --> 00:10:03.490 align:start position:0% it doesn't and it's a source you trust 00:10:03.490 --> 00:10:06.569 align:start position:0% it doesn't and it's a source you trust then<00:10:04.300> maybe<00:10:04.750> you<00:10:05.020> shouldn't<00:10:05.290> do<00:10:05.410> that<00:10:05.529> and<00:10:06.430> so 00:10:06.569 --> 00:10:06.579 align:start position:0% then maybe you shouldn't do that and so 00:10:06.579 --> 00:10:08.819 align:start position:0% then maybe you shouldn't do that and so what<00:10:06.670> you<00:10:06.790> should<00:10:06.970> do<00:10:07.089> there<00:10:07.300> is<00:10:07.829> actually 00:10:08.819 --> 00:10:08.829 align:start position:0% what you should do there is actually 00:10:08.829 --> 00:10:10.829 align:start position:0% what you should do there is actually like<00:10:09.070> fail<00:10:09.339> securely<00:10:09.910> so<00:10:10.450> rather<00:10:10.630> than 00:10:10.829 --> 00:10:10.839 align:start position:0% like fail securely so rather than 00:10:10.839 --> 00:10:12.660 align:start position:0% like fail securely so rather than failing<00:10:11.230> like<00:10:11.410> open<00:10:11.800> and<00:10:12.010> letting<00:10:12.190> some<00:10:12.459> sort 00:10:12.660 --> 00:10:12.670 align:start position:0% failing like open and letting some sort 00:10:12.670 --> 00:10:14.310 align:start position:0% failing like open and letting some sort of<00:10:12.700> payment<00:10:12.910> go<00:10:13.149> through<00:10:13.480> and<00:10:13.720> you<00:10:14.230> know 00:10:14.310 --> 00:10:14.320 align:start position:0% of payment go through and you know 00:10:14.320 --> 00:10:15.569 align:start position:0% of payment go through and you know credit<00:10:14.529> an<00:10:14.680> account<00:10:14.950> and<00:10:15.130> allow<00:10:15.279> that<00:10:15.339> to<00:10:15.490> be 00:10:15.569 --> 00:10:15.579 align:start position:0% credit an account and allow that to be 00:10:15.579 --> 00:10:17.430 align:start position:0% credit an account and allow that to be hacked<00:10:15.760> just<00:10:16.000> set<00:10:16.420> it<00:10:16.540> aside<00:10:16.630> like<00:10:17.140> put<00:10:17.290> it<00:10:17.380> in 00:10:17.430 --> 00:10:17.440 align:start position:0% hacked just set it aside like put it in 00:10:17.440 --> 00:10:19.380 align:start position:0% hacked just set it aside like put it in a<00:10:17.529> queue<00:10:17.800> alert<00:10:18.430> somebody<00:10:18.760> on<00:10:18.910> your<00:10:18.940> team<00:10:19.089> they 00:10:19.380 --> 00:10:19.390 align:start position:0% a queue alert somebody on your team they 00:10:19.390 --> 00:10:20.670 align:start position:0% a queue alert somebody on your team they can<00:10:19.450> investigate<00:10:20.050> it<00:10:20.079> and<00:10:20.230> see<00:10:20.320> what's<00:10:20.470> going 00:10:20.670 --> 00:10:20.680 align:start position:0% can investigate it and see what's going 00:10:20.680 --> 00:10:22.350 align:start position:0% can investigate it and see what's going on<00:10:20.829> and<00:10:21.100> then<00:10:21.610> they<00:10:21.670> can<00:10:21.700> determine<00:10:22.060> if<00:10:22.240> it's 00:10:22.350 --> 00:10:22.360 align:start position:0% on and then they can determine if it's 00:10:22.360 --> 00:10:24.600 align:start position:0% on and then they can determine if it's actually<00:10:22.600> a<00:10:22.630> bug<00:10:22.899> or<00:10:23.140> if<00:10:23.320> it's<00:10:23.470> not<00:10:23.620> and<00:10:24.459> so 00:10:24.600 --> 00:10:24.610 align:start position:0% actually a bug or if it's not and so 00:10:24.610 --> 00:10:25.860 align:start position:0% actually a bug or if it's not and so this<00:10:24.760> is<00:10:24.850> actually<00:10:25.000> this<00:10:25.480> is<00:10:25.600> the<00:10:25.690> kind<00:10:25.839> of 00:10:25.860 --> 00:10:25.870 align:start position:0% this is actually this is the kind of 00:10:25.870 --> 00:10:27.660 align:start position:0% this is actually this is the kind of stuff<00:10:26.050> we've<00:10:26.230> done<00:10:26.470> now<00:10:27.160> and<00:10:27.520> it's<00:10:27.610> actually 00:10:27.660 --> 00:10:27.670 align:start position:0% stuff we've done now and it's actually 00:10:27.670 --> 00:10:30.269 align:start position:0% stuff we've done now and it's actually really<00:10:28.029> helpful<00:10:28.300> even<00:10:28.839> outside<00:10:29.140> of<00:10:29.320> this<00:10:29.560> like 00:10:30.269 --> 00:10:30.279 align:start position:0% really helpful even outside of this like 00:10:30.279 --> 00:10:31.290 align:start position:0% really helpful even outside of this like since<00:10:30.490> we've<00:10:30.610> implemented<00:10:30.910> we<00:10:31.089> actually 00:10:31.290 --> 00:10:31.300 align:start position:0% since we've implemented we actually 00:10:31.300 --> 00:10:33.600 align:start position:0% since we've implemented we actually haven't<00:10:31.570> seen<00:10:31.660> anything<00:10:32.170> like<00:10:32.200> this<00:10:32.470> and<00:10:32.709> but 00:10:33.600 --> 00:10:33.610 align:start position:0% haven't seen anything like this and but 00:10:33.610 --> 00:10:35.220 align:start position:0% haven't seen anything like this and but what<00:10:34.029> we<00:10:34.120> have<00:10:34.270> seen<00:10:34.510> is<00:10:34.660> just<00:10:34.779> little<00:10:34.990> things 00:10:35.220 --> 00:10:35.230 align:start position:0% what we have seen is just little things 00:10:35.230 --> 00:10:36.840 align:start position:0% what we have seen is just little things being<00:10:35.500> off<00:10:35.709> here<00:10:36.010> and<00:10:36.130> there<00:10:36.250> you<00:10:36.459> know<00:10:36.490> some 00:10:36.840 --> 00:10:36.850 align:start position:0% being off here and there you know some 00:10:36.850 --> 00:10:38.370 align:start position:0% being off here and there you know some calculation<00:10:37.570> of<00:10:37.660> a<00:10:37.750> balance<00:10:37.990> is<00:10:38.079> slightly 00:10:38.370 --> 00:10:38.380 align:start position:0% calculation of a balance is slightly 00:10:38.380 --> 00:10:40.740 align:start position:0% calculation of a balance is slightly wrong<00:10:38.620> or<00:10:39.070> some<00:10:39.279> type<00:10:39.459> of<00:10:39.490> send<00:10:39.850> we<00:10:40.000> didn't<00:10:40.240> or 00:10:40.740 --> 00:10:40.750 align:start position:0% wrong or some type of send we didn't or 00:10:40.750 --> 00:10:42.050 align:start position:0% wrong or some type of send we didn't or some<00:10:40.870> type<00:10:41.020> of<00:10:41.050> receive<00:10:41.410> we<00:10:41.529> didn't<00:10:41.709> support 00:10:42.050 --> 00:10:42.060 align:start position:0% some type of receive we didn't support 00:10:42.060 --> 00:10:44.579 align:start position:0% some type of receive we didn't support and<00:10:43.060> it's<00:10:43.480> just<00:10:43.600> like<00:10:43.690> oh<00:10:43.810> it's<00:10:44.020> off<00:10:44.199> and<00:10:44.440> it's 00:10:44.579 --> 00:10:44.589 align:start position:0% and it's just like oh it's off and it's 00:10:44.589 --> 00:10:46.680 align:start position:0% and it's just like oh it's off and it's like<00:10:44.680> cool<00:10:44.890> it's<00:10:45.070> like<00:10:45.160> it's<00:10:45.399> alert<00:10:46.000> just<00:10:46.449> that 00:10:46.680 --> 00:10:46.690 align:start position:0% like cool it's like it's alert just that 00:10:46.690 --> 00:10:47.939 align:start position:0% like cool it's like it's alert just that something's<00:10:47.079> wrong<00:10:47.260> and<00:10:47.410> we<00:10:47.500> get<00:10:47.649> to<00:10:47.740> go<00:10:47.829> in 00:10:47.939 --> 00:10:47.949 align:start position:0% something's wrong and we get to go in 00:10:47.949 --> 00:10:49.170 align:start position:0% something's wrong and we get to go in and<00:10:48.100> fix<00:10:48.220> it<00:10:48.370> and<00:10:48.459> figure<00:10:48.640> out<00:10:48.699> why<00:10:48.880> and 00:10:49.170 --> 00:10:49.180 align:start position:0% and fix it and figure out why and 00:10:49.180 --> 00:10:50.490 align:start position:0% and fix it and figure out why and improve<00:10:49.600> our<00:10:49.720> systems<00:10:50.079> without<00:10:50.260> ever 00:10:50.490 --> 00:10:50.500 align:start position:0% improve our systems without ever 00:10:50.500 --> 00:10:52.019 align:start position:0% improve our systems without ever affecting<00:10:50.980> any<00:10:51.130> of<00:10:51.220> our<00:10:51.310> customers<00:10:51.730> which<00:10:51.910> is 00:10:52.019 --> 00:10:52.029 align:start position:0% affecting any of our customers which is 00:10:52.029 --> 00:10:54.210 align:start position:0% affecting any of our customers which is even<00:10:52.360> even<00:10:52.600> better<00:10:52.779> that<00:10:53.140> you<00:10:53.260> get<00:10:53.410> alerted<00:10:54.130> of 00:10:54.210 --> 00:10:54.220 align:start position:0% even even better that you get alerted of 00:10:54.220 --> 00:10:55.170 align:start position:0% even even better that you get alerted of things<00:10:54.399> that<00:10:54.550> are<00:10:54.640> wrong<00:10:54.760> and<00:10:54.790> just<00:10:54.970> like<00:10:55.149> oh 00:10:55.170 --> 00:10:55.180 align:start position:0% things that are wrong and just like oh 00:10:55.180 --> 00:10:55.590 align:start position:0% things that are wrong and just like oh cool 00:10:55.590 --> 00:10:55.600 align:start position:0% cool 00:10:55.600 --> 00:11:01.050 align:start position:0% cool I<00:10:55.630> can<00:10:55.839> fix<00:10:55.990> that<00:10:57.720> and<00:10:58.720> so<00:10:59.220> we'll<00:11:00.220> kind<00:11:00.670> of<00:11:00.699> put 00:11:01.050 --> 00:11:01.060 align:start position:0% I can fix that and so we'll kind of put 00:11:01.060 --> 00:11:02.880 align:start position:0% I can fix that and so we'll kind of put things<00:11:01.240> in<00:11:01.329> a<00:11:01.420> take<00:11:01.600> aways<00:11:01.839> here<00:11:02.079> and<00:11:02.290> sort<00:11:02.829> of 00:11:02.880 --> 00:11:02.890 align:start position:0% things in a take aways here and sort of 00:11:02.890 --> 00:11:05.639 align:start position:0% things in a take aways here and sort of sum<00:11:03.040> all<00:11:03.160> this<00:11:03.279> up<00:11:03.430> so<00:11:04.110> the<00:11:05.110> first<00:11:05.230> step<00:11:05.440> is<00:11:05.560> to 00:11:05.639 --> 00:11:05.649 align:start position:0% sum all this up so the first step is to 00:11:05.649 --> 00:11:06.960 align:start position:0% sum all this up so the first step is to check<00:11:05.800> the<00:11:05.829> receipt<00:11:06.220> status<00:11:06.579> it's 00:11:06.960 --> 00:11:06.970 align:start position:0% check the receipt status it's 00:11:06.970 --> 00:11:08.850 align:start position:0% check the receipt status it's it's<00:11:07.120> easy<00:11:07.360> to<00:11:07.540> check<00:11:07.810> there's<00:11:08.170> api's<00:11:08.649> for 00:11:08.850 --> 00:11:08.860 align:start position:0% it's easy to check there's api's for 00:11:08.860 --> 00:11:10.499 align:start position:0% it's easy to check there's api's for this<00:11:08.980> it's<00:11:09.430> a<00:11:09.519> boolean<00:11:09.850> field<00:11:10.060> you<00:11:10.300> know<00:11:10.389> it's 00:11:10.499 --> 00:11:10.509 align:start position:0% this it's a boolean field you know it's 00:11:10.509 --> 00:11:13.800 align:start position:0% this it's a boolean field you know it's true<00:11:10.689> false<00:11:11.139> basically<00:11:11.829> it's<00:11:12.069> numbers<00:11:12.370> but<00:11:12.810> so 00:11:13.800 --> 00:11:13.810 align:start position:0% true false basically it's numbers but so 00:11:13.810 --> 00:11:15.420 align:start position:0% true false basically it's numbers but so just<00:11:13.990> check<00:11:14.170> that<00:11:14.319> and<00:11:14.379> if<00:11:14.620> it<00:11:14.980> says<00:11:15.100> it<00:11:15.250> failed 00:11:15.420 --> 00:11:15.430 align:start position:0% just check that and if it says it failed 00:11:15.430 --> 00:11:17.819 align:start position:0% just check that and if it says it failed then<00:11:15.790> none<00:11:16.689> of<00:11:16.720> the<00:11:16.810> transfers<00:11:17.110> happened<00:11:17.410> the 00:11:17.819 --> 00:11:17.829 align:start position:0% then none of the transfers happened the 00:11:17.829 --> 00:11:19.079 align:start position:0% then none of the transfers happened the nuance<00:11:18.129> here<00:11:18.189> is<00:11:18.339> like<00:11:18.459> you<00:11:18.610> do<00:11:18.759> still<00:11:18.939> pay<00:11:19.060> for 00:11:19.079 --> 00:11:19.089 align:start position:0% nuance here is like you do still pay for 00:11:19.089 --> 00:11:21.210 align:start position:0% nuance here is like you do still pay for the<00:11:19.269> gas<00:11:19.420> here<00:11:19.779> like<00:11:20.199> failed<00:11:20.560> transactions 00:11:21.210 --> 00:11:21.220 align:start position:0% the gas here like failed transactions 00:11:21.220 --> 00:11:22.980 align:start position:0% the gas here like failed transactions are<00:11:21.339> still<00:11:21.490> included<00:11:21.699> in<00:11:21.879> blocks<00:11:22.240> because 00:11:22.980 --> 00:11:22.990 align:start position:0% are still included in blocks because 00:11:22.990 --> 00:11:24.960 align:start position:0% are still included in blocks because somebody<00:11:23.620> had<00:11:23.800> to<00:11:23.829> executed<00:11:24.459> all<00:11:24.579> the<00:11:24.699> miners 00:11:24.960 --> 00:11:24.970 align:start position:0% somebody had to executed all the miners 00:11:24.970 --> 00:11:26.249 align:start position:0% somebody had to executed all the miners and<00:11:25.180> nodes<00:11:25.509> you<00:11:25.629> need<00:11:25.750> to<00:11:25.810> execute<00:11:26.170> the 00:11:26.249 --> 00:11:26.259 align:start position:0% and nodes you need to execute the 00:11:26.259 --> 00:11:27.780 align:start position:0% and nodes you need to execute the transaction<00:11:26.439> to<00:11:26.860> the<00:11:26.889> failure<00:11:27.310> to<00:11:27.459> validate 00:11:27.780 --> 00:11:27.790 align:start position:0% transaction to the failure to validate 00:11:27.790 --> 00:11:29.939 align:start position:0% transaction to the failure to validate it<00:11:27.939> so<00:11:28.120> it<00:11:28.180> still<00:11:28.360> costs<00:11:28.720> like<00:11:28.839> resources<00:11:29.439> so 00:11:29.939 --> 00:11:29.949 align:start position:0% it so it still costs like resources so 00:11:29.949 --> 00:11:31.980 align:start position:0% it so it still costs like resources so even<00:11:30.160> though<00:11:30.250> it<00:11:30.370> failed<00:11:30.639> you<00:11:31.600> still<00:11:31.810> need<00:11:31.930> to 00:11:31.980 --> 00:11:31.990 align:start position:0% even though it failed you still need to 00:11:31.990 --> 00:11:33.480 align:start position:0% even though it failed you still need to check<00:11:32.050> it<00:11:32.319> and<00:11:32.470> they<00:11:32.680> still<00:11:32.889> do<00:11:33.069> actually<00:11:33.399> pay 00:11:33.480 --> 00:11:33.490 align:start position:0% check it and they still do actually pay 00:11:33.490 --> 00:11:36.360 align:start position:0% check it and they still do actually pay the<00:11:33.639> gas<00:11:33.759> for<00:11:34.089> it<00:11:34.209> but<00:11:35.079> but<00:11:36.069> none<00:11:36.220> of<00:11:36.250> the 00:11:36.360 --> 00:11:36.370 align:start position:0% the gas for it but but none of the 00:11:36.370 --> 00:11:40.170 align:start position:0% the gas for it but but none of the transfers<00:11:38.160> and<00:11:39.160> the<00:11:39.189> second<00:11:39.459> one<00:11:39.579> here<00:11:39.730> is<00:11:39.759> to 00:11:40.170 --> 00:11:40.180 align:start position:0% transfers and the second one here is to 00:11:40.180 --> 00:11:43.139 align:start position:0% transfers and the second one here is to parse<00:11:40.360> the<00:11:40.480> trace<00:11:40.660> as<00:11:40.870> the<00:11:41.199> tree<00:11:41.699> it's<00:11:42.699> there's 00:11:43.139 --> 00:11:43.149 align:start position:0% parse the trace as the tree it's there's 00:11:43.149 --> 00:11:44.639 align:start position:0% parse the trace as the tree it's there's information<00:11:43.750> in<00:11:43.899> the<00:11:44.019> way<00:11:44.139> the<00:11:44.290> trace<00:11:44.500> is 00:11:44.639 --> 00:11:44.649 align:start position:0% information in the way the trace is 00:11:44.649 --> 00:11:46.860 align:start position:0% information in the way the trace is formatted<00:11:45.040> and<00:11:45.310> the<00:11:46.240> trace<00:11:46.449> is<00:11:46.569> I<00:11:46.629> sort<00:11:46.839> of 00:11:46.860 --> 00:11:46.870 align:start position:0% formatted and the trace is I sort of 00:11:46.870 --> 00:11:48.030 align:start position:0% formatted and the trace is I sort of showed<00:11:47.079> here<00:11:47.259> that<00:11:47.410> I'm<00:11:47.500> describing<00:11:47.709> are 00:11:48.030 --> 00:11:48.040 align:start position:0% showed here that I'm describing are 00:11:48.040 --> 00:11:50.309 align:start position:0% showed here that I'm describing are parodies<00:11:48.370> death<00:11:49.180> has<00:11:49.360> the<00:11:49.509> tracing<00:11:49.810> API<00:11:50.050> exist 00:11:50.309 --> 00:11:50.319 align:start position:0% parodies death has the tracing API exist 00:11:50.319 --> 00:11:51.600 align:start position:0% parodies death has the tracing API exist to<00:11:50.470> now<00:11:50.620> but<00:11:50.829> it's<00:11:50.949> it's<00:11:51.160> they're<00:11:51.339> not<00:11:51.490> the 00:11:51.600 --> 00:11:51.610 align:start position:0% to now but it's it's they're not the 00:11:51.610 --> 00:11:53.639 align:start position:0% to now but it's it's they're not the same<00:11:51.819> it's<00:11:52.449> not<00:11:52.600> a<00:11:52.629> standardized<00:11:53.170> thing<00:11:53.439> and 00:11:53.639 --> 00:11:53.649 align:start position:0% same it's not a standardized thing and 00:11:53.649 --> 00:11:55.889 align:start position:0% same it's not a standardized thing and so<00:11:53.800> you<00:11:54.639> need<00:11:54.790> a<00:11:54.819> reference<00:11:55.000> sort<00:11:55.360> of<00:11:55.420> guests 00:11:55.889 --> 00:11:55.899 align:start position:0% so you need a reference sort of guests 00:11:55.899 --> 00:11:57.540 align:start position:0% so you need a reference sort of guests documentation<00:11:56.500> for<00:11:56.620> how<00:11:56.709> it<00:11:57.040> works<00:11:57.160> there<00:11:57.370> I 00:11:57.540 --> 00:11:57.550 align:start position:0% documentation for how it works there I 00:11:57.550 --> 00:11:59.730 align:start position:0% documentation for how it works there I imagine<00:11:58.089> it's<00:11:58.209> similar<00:11:58.360> but<00:11:58.870> you<00:11:59.500> need<00:11:59.649> to 00:11:59.730 --> 00:11:59.740 align:start position:0% imagine it's similar but you need to 00:11:59.740 --> 00:12:01.379 align:start position:0% imagine it's similar but you need to take<00:11:59.860> this<00:11:59.980> flat<00:12:00.250> list<00:12:00.430> they<00:12:00.610> provide<00:12:01.089> you<00:12:01.240> it 00:12:01.379 --> 00:12:01.389 align:start position:0% take this flat list they provide you it 00:12:01.389 --> 00:12:02.490 align:start position:0% take this flat list they provide you it sort<00:12:01.540> of<00:12:01.569> structure<00:12:01.899> it<00:12:01.959> into<00:12:02.110> some<00:12:02.259> sort<00:12:02.290> of 00:12:02.490 --> 00:12:02.500 align:start position:0% sort of structure it into some sort of 00:12:02.500 --> 00:12:04.710 align:start position:0% sort of structure it into some sort of tree<00:12:02.709> and<00:12:02.980> then<00:12:03.430> once<00:12:03.610> you<00:12:03.699> do<00:12:03.850> that<00:12:03.879> you<00:12:04.600> can 00:12:04.710 --> 00:12:04.720 align:start position:0% tree and then once you do that you can 00:12:04.720 --> 00:12:08.040 align:start position:0% tree and then once you do that you can inspect<00:12:05.310> these<00:12:06.310> sort<00:12:06.639> of<00:12:06.699> errored<00:12:07.120> sub<00:12:07.779> trees 00:12:08.040 --> 00:12:08.050 align:start position:0% inspect these sort of errored sub trees 00:12:08.050 --> 00:12:09.449 align:start position:0% inspect these sort of errored sub trees and<00:12:08.230> you<00:12:08.319> like<00:12:08.529> filter<00:12:08.829> them<00:12:08.949> out<00:12:09.100> or<00:12:09.310> mark 00:12:09.449 --> 00:12:09.459 align:start position:0% and you like filter them out or mark 00:12:09.459 --> 00:12:10.650 align:start position:0% and you like filter them out or mark them<00:12:09.610> failed<00:12:09.819> or<00:12:10.029> you<00:12:10.180> know<00:12:10.269> whatever<00:12:10.449> you 00:12:10.650 --> 00:12:10.660 align:start position:0% them failed or you know whatever you 00:12:10.660 --> 00:12:15.059 align:start position:0% them failed or you know whatever you want<00:12:10.689> to<00:12:10.870> do<00:12:10.959> there<00:12:12.870> thirdly<00:12:13.870> we<00:12:14.860> want<00:12:15.009> to 00:12:15.059 --> 00:12:15.069 align:start position:0% want to do there thirdly we want to 00:12:15.069 --> 00:12:16.799 align:start position:0% want to do there thirdly we want to reject<00:12:15.370> these<00:12:15.550> like<00:12:15.819> delegate<00:12:16.300> and<00:12:16.449> call<00:12:16.600> code 00:12:16.799 --> 00:12:16.809 align:start position:0% reject these like delegate and call code 00:12:16.809 --> 00:12:19.139 align:start position:0% reject these like delegate and call code calls<00:12:17.220> these<00:12:18.220> are<00:12:18.339> two<00:12:18.550> different<00:12:18.790> types<00:12:18.970> of 00:12:19.139 --> 00:12:19.149 align:start position:0% calls these are two different types of 00:12:19.149 --> 00:12:20.369 align:start position:0% calls these are two different types of ones<00:12:19.300> that<00:12:19.480> kind<00:12:19.629> of<00:12:19.689> look<00:12:19.870> like<00:12:19.899> they 00:12:20.369 --> 00:12:20.379 align:start position:0% ones that kind of look like they 00:12:20.379 --> 00:12:21.869 align:start position:0% ones that kind of look like they transferring<00:12:20.829> things<00:12:21.100> in<00:12:21.370> but<00:12:21.610> they<00:12:21.730> actually 00:12:21.869 --> 00:12:21.879 align:start position:0% transferring things in but they actually 00:12:21.879 --> 00:12:24.509 align:start position:0% transferring things in but they actually don't<00:12:22.149> and<00:12:22.470> then<00:12:23.470> if<00:12:23.829> you<00:12:23.949> if<00:12:24.160> you<00:12:24.279> kind<00:12:24.430> of 00:12:24.509 --> 00:12:24.519 align:start position:0% don't and then if you if you kind of 00:12:24.519 --> 00:12:26.790 align:start position:0% don't and then if you if you kind of take<00:12:25.329> the<00:12:25.480> the<00:12:25.750> earlier<00:12:26.019> point<00:12:26.319> about<00:12:26.470> failing 00:12:26.790 --> 00:12:26.800 align:start position:0% take the the earlier point about failing 00:12:26.800 --> 00:12:28.410 align:start position:0% take the the earlier point about failing safely<00:12:27.370> here<00:12:27.579> what<00:12:27.790> you<00:12:27.850> really<00:12:28.089> should<00:12:28.209> do 00:12:28.410 --> 00:12:28.420 align:start position:0% safely here what you really should do 00:12:28.420 --> 00:12:29.579 align:start position:0% safely here what you really should do here<00:12:28.569> is<00:12:28.629> actually<00:12:28.870> just<00:12:28.899> select<00:12:29.319> the<00:12:29.439> ones 00:12:29.579 --> 00:12:29.589 align:start position:0% here is actually just select the ones 00:12:29.589 --> 00:12:31.410 align:start position:0% here is actually just select the ones you<00:12:29.680> know<00:12:29.980> do<00:12:30.250> it<00:12:30.279> so<00:12:30.850> this<00:12:30.939> is<00:12:31.089> similar<00:12:31.360> if 00:12:31.410 --> 00:12:31.420 align:start position:0% you know do it so this is similar if 00:12:31.420 --> 00:12:32.429 align:start position:0% you know do it so this is similar if there's<00:12:31.569> an<00:12:31.660> upgrade<00:12:31.779> you<00:12:32.050> don't<00:12:32.199> know<00:12:32.319> about 00:12:32.429 --> 00:12:32.439 align:start position:0% there's an upgrade you don't know about 00:12:32.439 --> 00:12:34.259 align:start position:0% there's an upgrade you don't know about if<00:12:32.709> there's<00:12:32.860> some<00:12:32.980> sort<00:12:33.129> of<00:12:33.189> change<00:12:33.550> at<00:12:34.029> least 00:12:34.259 --> 00:12:34.269 align:start position:0% if there's some sort of change at least 00:12:34.269 --> 00:12:35.970 align:start position:0% if there's some sort of change at least you<00:12:34.389> know<00:12:34.600> these<00:12:34.870> ones<00:12:35.139> work<00:12:35.350> I<00:12:35.589> didn't 00:12:35.970 --> 00:12:35.980 align:start position:0% you know these ones work I didn't 00:12:35.980 --> 00:12:37.139 align:start position:0% you know these ones work I didn't mention<00:12:36.160> these<00:12:36.309> other<00:12:36.490> ones<00:12:36.699> but<00:12:36.910> these<00:12:37.000> are 00:12:37.139 --> 00:12:37.149 align:start position:0% mention these other ones but these are 00:12:37.149 --> 00:12:38.730 align:start position:0% mention these other ones but these are like<00:12:37.269> creatives<00:12:37.809> for<00:12:37.930> creating<00:12:38.170> contracts 00:12:38.730 --> 00:12:38.740 align:start position:0% like creatives for creating contracts 00:12:38.740 --> 00:12:40.309 align:start position:0% like creatives for creating contracts self<00:12:38.920> destruct<00:12:39.250> for<00:12:39.430> destroying<00:12:39.730> one<00:12:40.029> and 00:12:40.309 --> 00:12:40.319 align:start position:0% self destruct for destroying one and 00:12:40.319 --> 00:12:42.299 align:start position:0% self destruct for destroying one and rewards<00:12:41.319> for<00:12:41.350> like<00:12:41.529> block<00:12:41.740> awards<00:12:42.069> these<00:12:42.189> are 00:12:42.299 --> 00:12:42.309 align:start position:0% rewards for like block awards these are 00:12:42.309 --> 00:12:43.470 align:start position:0% rewards for like block awards these are the<00:12:42.399> kind<00:12:42.550> of<00:12:42.610> things<00:12:42.790> that<00:12:43.000> can<00:12:43.209> you<00:12:43.389> know 00:12:43.470 --> 00:12:43.480 align:start position:0% the kind of things that can you know 00:12:43.480 --> 00:12:45.780 align:start position:0% the kind of things that can you know credit<00:12:43.809> Ethan<00:12:44.230> like<00:12:44.350> other<00:12:44.529> ways<00:12:44.740> or<00:12:45.519> like 00:12:45.780 --> 00:12:45.790 align:start position:0% credit Ethan like other ways or like 00:12:45.790 --> 00:12:47.879 align:start position:0% credit Ethan like other ways or like send<00:12:46.120> it<00:12:46.240> and<00:12:46.360> so<00:12:46.809> you<00:12:46.870> just<00:12:47.259> if<00:12:47.470> you<00:12:47.500> select 00:12:47.879 --> 00:12:47.889 align:start position:0% send it and so you just if you select 00:12:47.889 --> 00:12:48.960 align:start position:0% send it and so you just if you select those<00:12:48.069> and<00:12:48.309> handle<00:12:48.519> those<00:12:48.639> cases 00:12:48.960 --> 00:12:48.970 align:start position:0% those and handle those cases 00:12:48.970 --> 00:12:50.730 align:start position:0% those and handle those cases appropriately<00:12:49.509> you<00:12:49.720> know<00:12:49.870> you're<00:12:50.079> sort<00:12:50.199> of<00:12:50.350> at 00:12:50.730 --> 00:12:50.740 align:start position:0% appropriately you know you're sort of at 00:12:50.740 --> 00:12:52.410 align:start position:0% appropriately you know you're sort of at least<00:12:50.920> reasonably<00:12:51.370> safe<00:12:51.610> and<00:12:51.819> then<00:12:52.240> if<00:12:52.329> you 00:12:52.410 --> 00:12:52.420 align:start position:0% least reasonably safe and then if you 00:12:52.420 --> 00:12:55.920 align:start position:0% least reasonably safe and then if you implement<00:12:52.629> this<00:12:53.040> next<00:12:54.040> point<00:12:54.660> don't<00:12:55.660> trust 00:12:55.920 --> 00:12:55.930 align:start position:0% implement this next point don't trust 00:12:55.930 --> 00:12:58.019 align:start position:0% implement this next point don't trust until<00:12:56.290> verify<00:12:57.040> it<00:12:57.100> right<00:12:57.339> verify<00:12:57.759> your<00:12:57.910> data 00:12:58.019 --> 00:12:58.029 align:start position:0% until verify it right verify your data 00:12:58.029 --> 00:12:59.819 align:start position:0% until verify it right verify your data check<00:12:58.449> with<00:12:58.569> other<00:12:58.660> sources<00:12:58.959> you<00:12:59.589> don't<00:12:59.740> have 00:12:59.819 --> 00:12:59.829 align:start position:0% check with other sources you don't have 00:12:59.829 --> 00:13:01.740 align:start position:0% check with other sources you don't have to<00:12:59.920> like<00:13:00.040> trust<00:13:00.430> it<00:13:00.670> completely<00:13:00.910> but<00:13:01.600> at<00:13:01.689> least 00:13:01.740 --> 00:13:01.750 align:start position:0% to like trust it completely but at least 00:13:01.750 --> 00:13:03.059 align:start position:0% to like trust it completely but at least it's<00:13:01.959> sort<00:13:02.139> of<00:13:02.170> a<00:13:02.259> signal<00:13:02.649> that<00:13:02.740> something's 00:13:03.059 --> 00:13:03.069 align:start position:0% it's sort of a signal that something's 00:13:03.069 --> 00:13:04.619 align:start position:0% it's sort of a signal that something's wrong<00:13:03.250> right<00:13:03.879> don't<00:13:04.029> just<00:13:04.180> take<00:13:04.329> that<00:13:04.480> and 00:13:04.619 --> 00:13:04.629 align:start position:0% wrong right don't just take that and 00:13:04.629 --> 00:13:05.819 align:start position:0% wrong right don't just take that and write<00:13:04.750> it<00:13:04.839> to<00:13:04.930> your<00:13:05.050> database<00:13:05.170> like<00:13:05.680> that's 00:13:05.819 --> 00:13:05.829 align:start position:0% write it to your database like that's 00:13:05.829 --> 00:13:07.769 align:start position:0% write it to your database like that's the<00:13:06.040> truth<00:13:06.279> but<00:13:06.819> what<00:13:07.180> you<00:13:07.269> should<00:13:07.329> do<00:13:07.569> is<00:13:07.660> at 00:13:07.769 --> 00:13:07.779 align:start position:0% the truth but what you should do is at 00:13:07.779 --> 00:13:08.730 align:start position:0% the truth but what you should do is at least<00:13:07.809> look<00:13:08.110> at<00:13:08.259> it<00:13:08.379> and<00:13:08.470> you're<00:13:08.529> like<00:13:08.589> all 00:13:08.730 --> 00:13:08.740 align:start position:0% least look at it and you're like all 00:13:08.740 --> 00:13:10.019 align:start position:0% least look at it and you're like all right<00:13:08.829> something's<00:13:09.129> weird<00:13:09.220> here<00:13:09.399> and<00:13:09.759> also<00:13:09.910> if 00:13:10.019 --> 00:13:10.029 align:start position:0% right something's weird here and also if 00:13:10.029 --> 00:13:10.740 align:start position:0% right something's weird here and also if you're<00:13:10.120> getting<00:13:10.209> a<00:13:10.329> lot<00:13:10.449> of<00:13:10.540> false<00:13:10.689> positives 00:13:10.740 --> 00:13:10.750 align:start position:0% you're getting a lot of false positives 00:13:10.750 --> 00:13:11.939 align:start position:0% you're getting a lot of false positives you<00:13:11.199> know<00:13:11.290> maybe<00:13:11.500> you<00:13:11.620> pick<00:13:11.740> some<00:13:11.889> other 00:13:11.939 --> 00:13:11.949 align:start position:0% you know maybe you pick some other 00:13:11.949 --> 00:13:18.210 align:start position:0% you know maybe you pick some other source<00:13:15.089> and<00:13:16.089> yeah<00:13:16.689> that's<00:13:17.139> it<00:13:17.350> for<00:13:17.559> today<00:13:17.769> so<00:13:17.829> I 00:13:18.210 --> 00:13:18.220 align:start position:0% source and yeah that's it for today so I 00:13:18.220 --> 00:13:19.410 align:start position:0% source and yeah that's it for today so I hope<00:13:18.309> you<00:13:18.429> all<00:13:18.519> stay<00:13:18.759> safe<00:13:19.059> out<00:13:19.179> there<00:13:19.240> and 00:13:19.410 --> 00:13:19.420 align:start position:0% hope you all stay safe out there and 00:13:19.420 --> 00:13:20.639 align:start position:0% hope you all stay safe out there and hope<00:13:19.509> everybody<00:13:19.870> we 00:13:20.639 --> 00:13:20.649 align:start position:0% hope everybody we 00:13:20.649 --> 00:13:23.030 align:start position:0% hope everybody we something<00:13:21.009> here<00:13:21.189> and<00:13:21.509> we've<00:13:22.509> got<00:13:22.629> I<00:13:22.660> think 00:13:23.030 --> 00:13:23.040 align:start position:0% something here and we've got I think 00:13:23.040 --> 00:13:25.259 align:start position:0% something here and we've got I think some<00:13:24.040> time<00:13:24.220> for<00:13:24.459> questions<00:13:24.759> about<00:13:25.089> four 00:13:25.259 --> 00:13:25.269 align:start position:0% some time for questions about four 00:13:25.269 --> 00:13:37.090 align:start position:0% some time for questions about four minutes<00:13:25.389> so<00:13:25.660> if<00:13:25.720> you<00:13:25.809> have<00:13:25.899> any 00:13:37.090 --> 00:13:37.100 align:start position:0% 00:13:37.100 --> 00:13:39.160 align:start position:0% you