StarkNet 101 Workshop - Getting started with unlimited scalability | Devcon Bogotá

foreign [Music] we're going to be talking in English and if you don't understand anything on the slides please let me know no problem but just focus on me so on the layer one we had amazing applications we got a lot of applications very interesting for example amms that could let you transact with different tokens but these were very very very expensive right we also had oracles that allow us to introduce data of chain into one chain right but it was also very expensive moving data on chain is expensive we also had gaming where you can have nfts very cute nfts you can have your sword for your game you're gone and so on you can maybe move it to another game but still the game was was lit was directed by a single entity that had the control over the game so the game Logistics the game logic was not on chain it was not Auto regulate it yes because it's very expensive right also we had both in apps but also again writing in the storage right into the blockchain is very expensive so voting was also real expensive on layer one so this is very interesting applications that we have in the layer one both that introduces problems when we are talking out costs so we know the states the current state of things is either we have a huge machine that is processing everything we know this and for example Banks Acorn apis companies startups and so on very huge machines they can process a lot of transactions very quickly and now we're looking at the blue Parts where we are trying to create a centralized system which is when a lot of persons can verify the Integrity of the system right this is what we're trying to do the problem is that this is very slow and this is very expensive and the computation repeated itself various times at different points so it's not optimal for scalability of course this was a choice when we decided to create theorem we wanted this centralization we wanted security it was a choice to sacrifice at that moment's scalability but now we know better and we can do better stuff so the question is can we head can we get the centralization security and also scaling yes we can do with your knowledge roles and we are here today to talk about star Nets so we're talking about a platformer layer 2 that is secure by ethereum it allows you to create smart contracts General smart contracts it's too incomplete the cost of execution is much lower and you can create amazing things that are not possible even imaginable in the layer one so we can get much more for each piece of gas so this is a quote from Albion session our founder at Bangles in the 29th of July he's talking about the objective of starnet which is creating a solution for scaling that is focus focus only on scaling theorem and this is called Cairo so our Star Wars are experts on both the attribution machine and also creating stock systems and there was a conscious choice not to use the evm to scale we created a new virtual machine called Cairo this is this WhatsApp comes choice because we believe this is a way to achieve the biggest scale and this scaling is going to it's going to come from Smart contrast with them in Cairo in Cairo is a virtual machine but also language we have so what is Cairo currents are doing complete language programming language that allows you to create brewable programs in this case in Spanish you can execute your Cairo program and then you can prove a smart contract on the layer 1 on assume that this a transaction was correct this allows us to have much more much cheaper transactions cost and because Pro when the smart contract on the layer one Valley days that this proof is correct it's much cheaper than running the transaction itself so this allows us to create more to get much more scalable Solutions uh using the layer 2 in this case with cat with Chiron starts so this is our solution let's generally follow-ups specifically talking about Chiron starnet you can get extremely extremely cheap computation thanks to Cairo and we can create and this is key we can create interesting applications that are only be that could only be made using the layer two it's impossible practically impossible to do on layer one this is an interesting data that we got during the last week a standard plus start startix blocks stagnant so Star Wars the company has different solutions one of them is star trekx and the other one is started that we're talking about right now and both together had more transactions since July than Bitcoin lining and all layer 2's this is something that is not very well known whereas you can see coming from July the blue line is the starcakes plus Stark Nets down is Bitcoin in Orange and under that are other layer 2 Solutions so as you can see Stark is an external it's currently being very very used and we have been live in Maine since June yes June 2020. so we are not new at this we know how to do it the Star Solutions is very good and as you can see it's very very it's been very used and very interestingly also is that 70 percent of that come from nfts it's very interesting for example with immutable with sorare interesting so now thank you very much for coming now we know that Stan has a lot of potential you can create needs whenever you want you can deploy it currently and actually today we'll be creating a boating application that we're gonna be trying on starnet you can use it Cairo is a different language we know it but it's also a language that everybody can use it's not hard at all so my name is Marshall Hill I'm a developer Advocate server and thank you very much for coming today the golf today is for you to get the resources to start to start studying Cairo if you want to go into starnet and also make a small example of a boring application so now we talk a little bit about what is being done in layer one that is very costly and we can improve what now let's talk about what can we do with all this power that chip computation can provide us for example we have a solution called ckex it's a company that is offering high frequency trading this of course is impossible in layer one imagine having micro positions and trading with them I don't know it would be impossible because of the course in the year one makes no sense we talked before about voting voting is very expensive too so there are also solutions for example snapshot X that allow us to bolt much more cheaply yes so there are a lot of applications that have been already developed since I started using all this power another one for example is the government of Buenos Aires create an application that allows you to have an identity on the blockchain as a user as a citizen they show they chose starnet because it's very secure it's highly highly secure and also it's very scalable and very quick so these are only some examples but the custom is growing by the day for example we have tools amazing tooling for example coming from hard hat open sepulime and chain link soon Alchemy those are well-known companies but we also and maybe more interesting we have different applications on the top as you can see that are being created originally on the layer too so this is very interesting because it's at least my opinion is not for the company overall but it is interesting when a company comes from Lane one and then puts its applications layer to it's great they are using the the lower fees and that kind of stuff however I believe that the real power is being used but those that are created natively on Cairo in the layer two yes it's a little bit like for example when you have Windows in your computer Windows 98 for example and you had this nice and cute games and then comes for example Windows XP right it's more powerful you can do much more stuff and these games can be can be passed into XP okay so these old games can be passed into the new software and they run well it's okay they maybe could leverage some of the power of the new operating system but the real power comes from that that is being built on top of XP that could not be done in the previous operating system right that's what we're talking about here something that is completely different and out of the leak of the layer one we can create something very very interesting that is impossible to create for example we were talking about the games that they didn't have the logic on chain is now possible so imagine that you can do operations summations multiplications divisions whatever you can do that because the gas is much much cheaper so a company I don't remember I know the num what is the name of the project that was creating this on chain reality topology so topology created a game on chain and it's Auto regulated okay so do you need a central limited to the sides if you're allowed to play it or not so it will stay forever as long as ethereum exists this is something that is again impossible layer one and for me those the powers is going to come from that part so now the question is um what can you create that is completely different from what has been created in the layer one using all these new power all these new potential that you can find in the layer 2. that is so completely different never done before imagine you can do for example machine learning on chain you can print models on chain you can create any kind of mathematical operations on chain it's completely different and what we need is people I start building these applications that are eye-opening so uh for the beginning you would need to start installing Cairo starnet hey of course I don't expect to expect you to do it right now but you can follow these QR codes for some instructions on how to install Cairo and starnet so you can get going it's not difficult at all and say while you scroll it we also have a report that is called started edu where you can find a lot of educational material I will show you the link with in a couple moments and Inside Story du you can find a lot of tutorials on different stuff for example you can know how to how the cowboy syntax look we're going to look at it in a moment you can for example create a token an erc20 you can create your nft your c721 tutorials for even more interesting how you can create your own Bridge from layer 1 and layer 2. Bridge and for example how can you create your own wallets so you can if you can scan this QR code you will find all that material inside and you can get uh going by yourself without without any problem those tutorials are amazing and they have onboarded a lot of people into the ecosystem also we have a newsletter that is very nice and you will have a lot of educational material there too and also some interesting projects happening on the on the on the ecosystem it's also there you can subscribe it's a soft stack newsletter and finally what we're going to be doing today is a voting application they will allow a person to either vote for one or zero one for yes for example zero for no and deploy it on the test Nets if you have any question until now you can tell me this is the report that we're gonna be using so if you want to have the report you want to clone it you want to copy the code or just look at it feel free to scan these QR codes any questions comments well we'll start with the coding parts oh okay and I have a question actually how many of you know how to code in solidity can you raise your hand how many of you have ever coded in Cairo oh a few of you cool coming from so late into Cairo is very simple yeah really really simple and it's great that you're already working with solid perfect you want to go to Tesla and see away and interact with with this contract feel free also to scan these QR codes the test Nets already working with this both team contracts foreign here if you want to come also and I don't know guys do you want to add something else before we start going oh perfect okay do you need another QR codes uh do you have already the the one with the contract will win we're going to use is this one remember please so let's go to the counts so this is our boating contract again the goal is to create a contract that allows certain predefined addresses for example me as the admin of the of the of the boat I can tell okay this address can vote this or address can both these are the Rescue Bots because we don't want everybody to be able to post only certain participants of of a project I don't know and they will be able to vote Yes or no just with one no with zero and yes that will be all so for this let's review the structure and how Carol looks here we are importing our packages very similar to how it looks in python as you can see it then we Define its drugs as you would for example in Rust flush the grain are both counting structs where you will be able to store the boats with yes or no so for example we'll have 10 volts with yes zero bolts with null something like that the counting of the boat secondly we have border info where we store information about the Border in this case I only very simply allowed I simply added an allowed member that it will have a one if it's allowed to vote or zero if not if if this person has already vote it will have a zero now coming to the storage this is storage variables uh allow you to know if you're not solid already these are very similar to you they allow you to map from when um from one expression to the other in this case for example the first one now let's go to the third one here I am able to map and address to to a is register Bible that in this case is a field so Cairo is type it's a type language now you might ask yourself what is a felt everything is a fell inside Cairo conversion to Felts and basically for our purpose right now if you want we can get a little bit deeper in a moment both for now in order to to get to make the most of the time I felt it's like a big interview a huge interior number okay so in this case as you can see the address has not address type as in solidity it's a field okay so we're mapping an address there is a failed to a field called is register that will have a one or zero or whatever we haven't defined it yet and on the other ones we are mapping our information and interestingly in the first one we are mapping nothing yes nothing to a structure about Counting so this allows us to read or write into the memory that's as simple as that I can read this or I can write into the memory using these ones so using the storage variable boat in status and if we read it and if I I will go right now to the deploy contracts so this is the deploy contract I'm using right now boilinger which is a Blog Explorer for starnet if I go to the read part of the contract I can see what both in his status is doing using a getter function that we will see in a moment you can see the status of developing right now because nobody has both Jets we have zero codes with this three boats would know so that is the storage we are reading right now this storage variable will I get our function that we'll get to that in a moment and also we have the boring info and it's the same everyone goes into this but basically we're storing information into the uh in this into the storage of the of the blockchain now let's go to the Constructor looks very similar you know we're doing an initialize your your contract with your deploy it you have to Define certain inputs as insulated exactly the same name so this Constructor will ask for three different input Bibles as you can see now we can we can view how the a function looks into Cairo it's very simple very similar also to to Python and what is important here is this part these are the inputs the explicit inputs to this function in this case the inputs for the Constructor that we have to provide it when we deploy this contracts so I'm asking for an admin address the person that's going to be able to to manage this contracts with a felt again then the number of addresses that will be able to vote and finally the disappointed so it's important to know that Cairo is a low-level language so here we can manage the memory we have to manage it so the register addresses is basically a vector with a different addresses arrival to both I can add five six seven eight whatever and this pointer felt points to the start of that Vector but you would even notice that this the logic behind it is that this is pointing to the start of this array of different addresses but you won't you will notice this do as you will see then we're basically using a contract because we have open simply on top also of stone it so you are able to use a very secure contracts thanks to open sampling and we're using the owner will contract from our principaline before I import them here so I imported The Honorable a contract and the possible contract libraries from openstepperling owner will basically defines who the owner is of something and possible it allows you to post a contract in case of an emergency say that for example my application is being hacked so I can pause it as simple as that but also we have erc721 Logics and erc's 20 so you can use it with open supplement that's very very useful very very useful any question until now we have seen the Constructor we can see in the storage variables Strokes how to import how are you finding Cairo too difficult or is it nice any questions yes have you sorry what was the question yes for example we have in this case we will be using addresses that are in an Excel in hexadecimal format right it will simply be converted to a field behind it will be we will actually deploy right now our control using hex hexadecimal values and you will have to convert two Fields but you also could compare it to a field and also you play with this no problem right now we can think of it like big integers and we can get deeper into that any other question right now we have seen Constructors towards variables Strokes well perfect okay so here our Constructor and with this we can deploy our contracts also this um as you can see the structure of the contract is very similar to solidity we're trying to follow the guidelines of smart conducting solidity you have Getters you have the Constructor and the format is very similar also if you go to this contract is very well commented so you can know what is happening because foreign I think you guys can yeah sure so there's no inheritance in Cairo you don't inherit your contract what you do is you import your function so if you're looking at the the top of the uh of the contract up there here is importing a templates developed by open the printer is importing the full contract which is called audible so it means that he Imports all the functions that are inside of this contract and inside of this contract you know it creates it creates a few variables that can be initialized and um one of them is called the initializer which is supposed to be called during this Constructor does that make sense yes I was just curious because usually that's thread so it's not explicitly it's not automatically initialized because um because it's not like the contract is not ownable it Imports some function and it has no way to know that this is the specific context of the Constructor so you need to initialize it explicitly regarding the question on felt earlier um I'm not sure what confuses you but when you're looking at variables in solidity you know at the bottom of it at the end of the day it's a number and Cairo is a fairly new language it will get better in the next few months but right now it treats everything as a number so if you want to perform actions when you need strings you basically need to assume that you receive them as numbers you convert them you do your operations and you do all this kind of stuff make sense sort of yep yeah so a felt is as you mentioned earlier I think I heard you say it it's a field element so Cairo is like the felt you can't think of it as a big end but it's basically a number over a big film The Field that is a prime that does indeed uh um field integer mathematics and arithmetics that makes sense so it's really like you can treat it as modulo operations the only time where it gets weird is for divisions division sucks I don't like them no problem with that so for example we were talking about the honorable contract this is the one that were important so we have it here locally and we're importing for me this is the owner which comes in a namespace so we're importing these functions yes there are no inheritance in Cairo perfect so going back to I can't read two so we import these functions honorable and possible from functions inside the ownable namespace and inside the possible namespace you can yeah and there's a question [Music] foreign [Music] yes open Zeppelin is working to create the standard implementation so any kind of contract you have on solidity you're used to have that is done by open Zeppelin we're walking towards having that that being said I mean it takes time to develop contracts that are secure and everything so if you want to develop them you should it's worth it it's fun and you know you may develop stuff that gets used by other people which is great this actually principally the contracts incredible principling they have a lot of contributions from people outside the community so that will be where it also if somebody manages to write a Cairo contract that is the equivalent to this taking contract in synthetics which is used by everyone I'll buy you a beer more than a view [Music] [Laughter] it will eventually happen it's very if you it's one of you okay so we got our Constructor and then we can get to the here we're using the initializer function inside the ownable namespace and then we go to the Getters is very simple functions by definition in Cairo are private not like solidity so here if we want to have Getters functions to read information we have to explicitly tell that they are getters so and something that I forgot to mention before but this is the way like very similar to how you do it in Python how do you define that this has a particular set of properties this function that that is coming in this case with view we are defining get our functions functions what you can read from so right now we're creating this admin function that as you can see is exactly the same format as it comes in open sapling for example in erc20 or erc721 simply reading who the owner of the contract is so for example if I go again back to the contract deploy control here I can read who the admin is as you can see this is a field but if I convert it to hex this is the owner of the contract that is myself is this same direction so talking about wallets it's a good opportunity right now you can use right now RDM X which is this one and also Bravos that is this other one very recommended you can use the Standard faucets you can simply put in Google started faucet and you will be able to send yourself some fake it so you can start making some interesting things using girly or more interestingly you can also Bridge your own it from the girl testnet in in the layer one into the layer to start it for example here we're using program I can I can ask for some fake it send it to my metamask for example and then using the bridge I can connect my meta mask which is currently my my wallet in layer one and connect for example RDX here as my wallet layer 2 and I can reach these fake it from girly layer 1 to layer 2. so this is also very interesting it's the same thing as asking for it in the faucets so going back to the contracts we have another gear function here it's also a very typical open setting style function where you what we are posting we're asking when we think if this contract is currently post very simple and then more interestingly here we have a view function to know the boring status is the one that I showed you before it will let us know how many people voted this how many people bought it now as simple as that again you can see in this function that we have an explicit argument and by now you are already asking yourself what is this what is this inside these keys these are implicit arguments this is something that is different from other languages you might not seen that before but basically uh these repeat themselves all the time Cisco pointer person pointer and Rich check Pointer while interacting with the memory here so we are talking that these are Pointers actually into a felt and to a stroke Circle has built it no problem no we will need to get that that is something that we're repeating in each function it doesn't matter the real use is here so we ask in here for an explicit argument that is about Counting sorry sorry we're asking for nothing here it's empty the inputs and the output is this a status a variable called status that is about counting structure that we saw before again Kairus type is a type language this helps for security any question until now for this function for example yes yes this is again you can read it you can read from the gates boring status this is the one that I was showing before and currently the votes are yes or no this is practically in the structure we have and Define here this one both yes both know it's exactly the same here Okay so foreign [Music] [Music] [Music] explicitly telling these functions that you have passed them so they for example when we are reading from the from the storage you have to provide these functions that the sorry the pencil pointer and the Cisco pointer you have to provide them and they go into the read function so inside here our implicit function implicit arguments you don't see it because they are implicit but yes exactly this input functions if I take them off they will have an error no problem it's it's not hard to to to get used to them and also you can see each function that I adding here has them repeated so no problem with that okay also we have an overview function where we are getting the status of a motor and just if you were simply reading into the voter info a storage variable that we have before using the argument reads so now going deeper into this we can read and write from this storage function in this case we are reading and as you remember this search function asks us why do you surround device and it was precisely a failed so if we provided a field then it will return us let's see once does it return yes if we provide an RIS it will return us about our info structure okay so here I'm reading from it and then we're returning it simply as that status equal status because the name of the variable here is a status and to see an example of how to write exactly the same the same storage variable that we saw before motor info we were able to read from it if we are imputing with the address and we know we now know that it returns an instructs okay so now we can write using the argument right we can write on it so we're writing on the storage of our contract and right now this is basically an address we will go deeper in the moon over it but this is an address for this address please map this instruct okay very similar to how you look at it in solid yes sender is a I think we have it here get code address with this you're getting the address of the of the contract that is calling this this contract so for example in this case this is the most important function is the both function so what it does is simply it's getting the address of the color is turn it and then we'll reviewing the information of this person to see if this person has already bought or not because we can only allow them if they have bought it and just in a moment we'll go into that um could you repeat the question a little bit louder please value like an address there's no notion of msg.

value in stock net because there's no native currency everything's in near C20 so there's no value attached to a call there's no um and there's no payable function that answer your question Okay so yes [Music] um so let's go quickly into the most important function the two most important functions the register voters and this will help me to and talk a little bit more about recursion that we use in Cairo so again as you can see we have the implicit arguments as always and then we are asking for two explicit arguments the register address Lane this this is the the length of an array and the second value is the array itself so first argument is the length of the length of this array the second argument is the the array by itself then what we're doing here is and again you can see all these contracts in the report I showed you before isn't started with you in case you are you want to follow it closer in your houses and then what we're doing here is simply and this is a at least a classic function of Cairo that is using recursion so right now we don't have Force in Cairo you have to use precaution and this is a classic function for it when we review here is that uh it is the end of the recursion so if we have already passed to every each of these different members of the array that is if the length is zero then we can return and the recursion is finished then he will create a small a small struct the water info do you remember we defined the stroke called motor info here we are creating this butante info where we have this new motor info so empty anything here that allow is equal one it could be zero for example so this function what it's doing is that each of the address that I'm providing it will register them as voters and we tell we tell us that they are allowed to vote okay and then continue a little bit with the recursion what we're doing here is writing into storage into the storage variable register motor yes this one we're mapping as you remember before we mapping an address to a number so this is an address what we have here is this is the array as very similar as you would do it in Python for example on all languages you have that right and you can index to it using the square brackets okay so I am indexing in the inside this array for this could be a number like one or two or five depends on the number of address that we are adding and then we say that the value for that address is one we are simply mapping it here and then we become the recursion part here we are reading again the same function and providing the length but this is a lower length as you can see if we have for example five different voters that now we are providing it with four okay and we are sending it with the register address and then it will repeat it will repeat until it passes through each of the different addresses and it is starting for from the last one up to the first ones I know what this looks a little bit crazy here using caution Bots it's no problem you you can get used to it and I think that this will improve in the near future right yes well that's a good question the question is that what happens if you get into an infinite recursion um you okay so there's there is the there's an answer for today and an answer for tomorrow but basically there's a form of gas metering in starknot just like in ethereum and if we reach a match maximum number of steps the sequencer will recheck your transaction today you're not you don't pay for this kind of transactions they're just rejected tomorrow um you will be it will be like a fake transactional ethereum you will pay fees for the execution that led nowhere good perfect any other questions for a moment okay so simply we have a recursion function here again it's not that hard and it will improve we're talking that Cairo is a low level language and we have to be very honest and conscious about that and finally let's go to the last function that is the Boating function this will allow us to call a function as as you can see here it's an external function external function simply means that we can write on the storage using it okay not only reads but we can hear right into the storage again we have our implicit arguments we have an explicit argument called both and here don't mind this part simply telling the memory that we will be using the compiler that will be using local variables we don't need to go through that we're called the possible function from from open sampling contracts specifically the function called assert not pause it checks that if if this control is false or not if it pause this person cannot vote as simple as that then you get the caller address this was a question from before with this function we can get the address of this color we're storing it inside the color function then we can read the information of this color of this address using the reads argument from this touch variable that's already the nympho and then we are simply reviewing is this person can vote or not if they have a low zero then they cannot vote then we're creating a new bullet border info extract that it says that this person has already bought because we wanted to vote again we are writing on the storage here everything here we already know that and finally we are updating the status of the boats with the vote of this person if this person voted yes or zero in this case then it will update that with zero the count with zero and if they bought it yes in this case one for example then it will be updated the count will be updated with a sum that we have here and finally we are updating the final status of our update the story of our voting and storing it into the storage as you can see this function is scheme and if we go to the deploy contract we go to the right contract and then I can vote in this case this is the function I don't remember where I say and that I think so I will go to my Bravos wide in here I was in my origin before and let's see if it allows me to vote so I will vote with that one and I will be able to sign this transaction because this address is registered to both I did when I deploy it and right now what it this is the transaction hash and we have to wait for a test to process this and we will have our bolts now how can you deploy these contracts you can deploy it using the command line tools by its targets or also and my preferred ways to use protostar protostar is a tool created in the image of Foundry it has the best practices from Foundry and also some from haircut sorry from profile so it's very interesting it helped us to to test but also to deploy so if I go right now to my command line [Music] this is how deploying this contract looks like so basically I'm saying entering protostar deploy this a contract that is already compiled by this moment and what I want you to notice here is the part of the inputs it took before about the Constructor a setting for three different inputs first one is the owner the admin of this voting second is the number of persons of register addresses that can vote and finally the actual addresses so this is how they look this one as you can see is a hexa a hexa value and this is the address that is the owner of this contract then only one person or one address can vote this one and we can simply deploy it run it like like this photo store is very good it's very usable it has amazing testing functionalities but you can also deploy your contracts and that is simply the content that we deploy here and as we as we can see we already bought it if I go to read contracts we should get a boat in status where we had a boat with yes we're number one it updated and zero is still no I could note both again because uh directly theoretically I should not be able to vote again let's see what happens oh it should be it should it shouldn't pass right now but let's wait for it so that would be the the main part of the workshop you we have three minutes two more questions yes [Music] the implicit right now here I don't have any but they can change depending on what you're building can you think of a scenario and when do implicit arguments change every time they're used basically um it's a it's a bit of a deep question the workshop is about to finish so if you want let's meet outside and we'll we'll give you a a more definitive answer yes I think I have another message here hey will I look for it any other question in the meantime I have a question for the audience before we wrap the the workshop up can we get just get a quick show of hand who learned something during the workshop cool who thought this was too difficult who thought this was too easy okay fine so it's great this means this was spot on those of you still are hungry don't estate ask us question come on our Discord go on our resources look at what we do as also as Omar mentioned like most of these things the Paradigm you're used to that you're used to how you write smart contracts how you deal with Scholars and stuff like that this syntax is a bit different the tooling is a bit different but you can and will Master Cairo it's just a matter of just like trying and this will give this tool will give you extreme power in your blockchain applications so if you're looking to go more to do more and go beyond what you can do with the evm I invite you like do take a look it really is powerful and will let you build super cool stuff and again this is the QR to the educational resources you want to go look at them we'll have a boots on Thursday and Friday you can ask ask any question come with us and finally regarding the question the the error messages this is how they look so if this assertion true or false fails then it will print this mistake motor info well thank you thank you very much well it depends on the on the wallet uh let's see for example this case a certain Lounge yeah so what your question is what does a narrower message look like from the browser perspective essentially you'll get a failed transaction like you do on ethereum and the trace like the way it shows up is kind of ugly to be honest it's still very rough around the edges there's a lot of info that is not necessarily relevant to you but the message the error message will appear somewhere and you'll be you know able to know where the error is from in general this thing works and this feels scale this thing scales ethereum right now it's a bit rough around the edges meaning that it's not all pretty there's a lot of info or not enough but uh but it works and that's cool that's cool though this is how the error looks like as you can see that's the message that we saw before in there yeah explore info your address is not allowed to boot then we will have a boot please feel free to ask any questions and thank you very much for coming [Applause]