Perfectly. Thank you very much, friends. Wow, powerful microphone. So, we're ready to start. Thank you for coming, friends.
My name is Kevin Jones. I have a couple of workshops today. Another one will be at 3:30 PM about The Graph protocol. I work at Edge and Node on The Graph protocol, and I also support the Ethereum Foundation as a member of the Build Guild. This workshop is dedicated to developing applications on Ethereum, especially in the era of AI.
We'll talk about some tools worth knowing, and then try to quickly build an app to show app to show how it works. Who among you has already used Scaffold ETH? Anyone? One person. Okay, great.
Then it's perfect because everyone will be able to understand what Scaffold ETH is and why it's important. Scaffold ETH is a product that came about thanks to Build Guild. Build Guild was created by Austin Griffith. He couldn't be here today, so I'm replacing him. We have several tools for those who are coming into this field or want to truly understand Ethereum development.
One of them is Ethereum development. One of them is Speedrun Ethereum. I highly recommend trying it. Even veterans of the field will find something new for themselves after completing the Ethereum Speedrun. This is a kind of assignment, a series of challenges on Ethereum use cases that validate your skills and understanding of the protocol understanding of the protocol — from NFTs to crowdfunding.
How to attract many people from all over the world to invest money in a smart to invest money in a smart contract? You will learn a little about token about token vendors. I think I was rejected there. I do n't know why. I swear, I understand how it works, but a works, but a vendor token is an ERC20 concept: what is a token?
How does a token gain value? What are the patterns needed to work with a token? And then you learn a little about randomness. After all, in a deterministic blockchain, randomness can be a problem. And so you learn in this example how you can " how you can " hack" the system a little bit to understand what the real outcome might be, and that teaches you what exactly an oracle can provide.
Then you move on to more advanced topics like building a DEX, right? How to work with liquidity pools, right? For example, adding assets to the pool, receiving a token, and understanding that for a decentralized exchange to function properly, there must be a certain balance. Next comes the section on oracles and over- collateralization, which is quite interesting, isn't it? This is similar to how a protocol works: how to get lots of people to invest money in a smart contract, and then allow people to borrow funds from that contract.
It teaches you to create incentives so that anyone in the system can participate, and if someone doesn't follow the rules, they can essentially be liquidated using a decentralized smart contract. So that's very interesting, and then it flows smoothly into stablecoins and understanding what an overcollateralized stablecoin is and how it works. These things gradually complement each other. And one of the most interesting new sections is a whole guide to prediction markets and ZK- prediction markets and ZK- voting. And when you get through all of that, you'll be ready for the capture the flag ( capture the flag ( CTF) competitions we usually host at major Ethereum conferences like DevCon or Dev Connect.
We conduct them both live and virtually online. And there is also the " ETH technology tree" consisting of many different topics that you can start exploring to find your niche and what you are interested in learning. So come to the Ethereum speedrun. Enough advertising. But the second product to come out of Build Guild, or Buidl Guild, however you pronounce it, is Scaffold ETH.
And that, in fact, was my introduction to Ethereum. Before working at Ethereum, I worked at EngineX. And I was very interested in the concept of decentralization and programmable money programmable money . But at that time, there were too many different tools to understand which solution would be the best. And when I found Scaffold ETH, I realized that this is everything you need in one place as a starter kit, right?
And that was kind of my introduction to Ethereum, very, very valuable, and things have changed a lot since then. Now it's just one command that you can run through npx create, and it will deploy an entire decentralized application for you, smart application for you, smart contract, network, interface—everything is already connected, so you can start bringing your idea to life right away. Isn't that right? So this is perfect for hackathons, right? Because at hackathons we try to get started as quickly as possible.
And this will help you. In addition, we tried to make it very easy for artificial intelligence to understand how to work with the ETH scaffold. And we'll talk a little later about how that works. Another thing everyone should know about is ETH skills. So, if you go to eSkills.
com, you should add this skill to any coding any coding agent you use, because it has all the best practices for Ethereum smart contracts , code reviews, and the principles that Ethereum is based on: censorship resistance, open source, privacy, etc. We have all these different skills for different parts of Ethereum, and they come together to help you build an AI application that is as good as modern AI tools allow. You can see that there are many different skills here. Depending on what you're working on, you could just give your AI this website, and it could go to it, figure out what you're trying to create, and put your idea into practice your idea into practice , right? So add them.
There is a prompt here that you just need to copy and paste when you start a project, and it will help you. So let's move on to scaffold eth, maybe we'll try to build an app, and I'll show you some of my best practices. If you go to scaffold eth.io, there is a link to the documentation and to the GitHub repository. GitHub is, of course, open source, and there are details there explaining how it works, how to configure it, and all that.
But in reality, the documentation, probably if you're the kind of person who really wants to understand what's going on, will be the best place for you to find solutions to problems or figure out some of the nuances. One of the cool features of scaffold-eth is that it automatically comes with a blockchain and frontend. And, more importantly, all the frontend code is already written for you to some extent. So, if you're not a front-end developer, you know, it's a lot easier now with AI. But it's even easier because AI really " because AI really " loves" starter kits, and scaffold has some ready-made components and hooks that you'll see on the left to be able to interact with Ethereum, you know?
So when your smart contract outputs a certain integer or, sorry, a certain value, and you're trying to figure out exactly how to parse it, these are already pre -written things that are automatically generated every time the contract is deployed. So it really, really helps with ideas and the use of AI. Let's try to get started. So, I'll copy this command right here. So, npx create-eth@latest.
And we'll just launch it here. It's like a "choose your own adventure" game, right? Where you install the package install the package , the latest version. So, this is 2.0.
22. And then it will ask you what you want to name your app. So, we'll call it Lisbon. And then it will ask which chain you want to use. If you're a beginner, I mean, if you're using AI, it does n't really matter.
Hmm, there are some differences. I would say Foundry is a little faster. In Foundry, you can write tests for smart contracts in Solidity. I think it's possible in Hardhat too, but I don't know if we've updated the Hardhat version, but Foundry is a little faster. It doesn't really matter.
I personally use Hardhat, so I always choose it since I've been using it for ages. Now it's hard for me to change anything. So it will do the following: it will take the chain you want to use, the project name, and then it will simply deploy the entire application for you and install the dependencies. Scaffold-ETH dependencies. Scaffold-ETH is a Next.
js application, so it's pure Next.js, it will install all of these packages, as well as Hardhat or Foundry, depending on what you choose, and then it will tie it all together . This should only take a second. I hope the internet works here. At such events, it is always doubtful whether everything will work.
But what I want to say next is that if you want to configure Scaffold-ETH manually—and I recommend you figure out how it works—then you should split your screen into multiple terminals or open them in multiple windows. Because one window is needed for the blockchain, for your local chain. You need one window for the frontend and then a third window for deployment and things like that. So it's good to have a few windows open. I'll just split the screen into multiple windows.
You can just open new terminals, but I do it this way because it's a little more convenient. And then in each of these folders or in each of the terminals, go to the project you're working on, okay? I personally use Cursor because I like to visually see the changes that are happening. It's really up to you. You can also use VS Code if you want.
But I'll tell you a little about why I use Cursor. There use Cursor. There you go, the process is complete. You will see a message saying, "Congratulations, your project has been created," and all the commands for configuring your application will be provided. Let's quickly try to do them.
So the first one is starting the chain, right? The second is contract deployment, and the next is contract deployment, and the next is frontend launch. Scaffold uses the Yarn package manager. This means there are easy-to -remember commands and ready-made scripts, so you don't have to remember long commands. So, we run the chain with the " the chain with the " yarn chain" command, right?
This will launch our local blockchain. Oh no. Uh-huh. Maybe we should stop this. Let's see.
OK. Well, let's see. Uh-huh. So, it says that I have... something blocking...
I already have a thread running somewhere else. So, I don't know why, but for some reason something got stuck or something. So, let it end. That's it. Okay, we can stop this now.
Oh, this is an anvil. That's why. Sorry. Okay, everything is fine now. So, yarn chain will run our frontend or, well, our blockchain.
It's like a virtual blockchain virtual blockchain , right? I think you've heard of Hardhat before. Um, and here we are going to launch our frontend. So, the blockchain is on one terminal, and your frontend, i.e.
Next.js, is in this window. And in this last window, you will manage your environment. We will deploy the contract using the yarn deploy command. Scaffold comes with a ready-made starter contract so you can get started quickly and build whatever you want.
He needs to load the compiler, which as you can see he just did. Then he compiled it and executed this script. Perhaps the most interesting thing about Scaffold-ETH is that it takes the ABI, that is, the application's binary code interface. For those new to Ethereum: contracts are written and compiled into compiled into bytecode, which is incomprehensible to humans and your frontend as well. So, essentially, you need an ABI.
It's like a map that clearly shows how to interact with your contract. What's great about Scaffold-ETH is that it takes this ABI, parses it, and creates types in your frontend so you can easily work with the data of the deployed objects. Right? So we can start building the frontend right away, or our AI can do it for us because it just sees all the types and builds everything we need. Now that the application is deployed, let's take a quick look at Scaffold-ETH.
It runs on port 3000. It will take a second to compile and load, and then I'll show you why Scaffold is so useful. We don't have much time, so maybe... Oh, that's not very good. Maybe it's different...
Did it download somewhere else download somewhere else ? Oh, this is a bug, right? This is interesting. Good. Well, that's not very good.
Let's see. Um, we'll point it here. I just…This is probably the first lesson if you're debugging with AI. Copy the error you received and let's see if we can figure out what it is. Um, I recommend that if you use AI, you use at least Opus 4.
6. Some might say, "Oh, use Fable or something." Honestly, I think Opus 4.6 is pretty good, especially for prototyping and development. So, he will try to fix this addiction.
Maybe it's a bug that was recently added or something like that. I noticed that there was a new version of Scapple that I installed. So this could have caused an error. Let's see. Let's try a quick restart and see.
Here it is and see. Here it is . Good. OK. So, yes.
So what we have here is Scaffold ETH. It's rebooting now, so let's give it a second so let's give it a second . But what's great about Scaffold is that it's a very basic app that lets you start exploring everything around you, and what's really cool is having this burner wallet right here in the corner so you don't have to plug in MetaMask. This is simply because with MetaMask you may have issues with the local chain nonce, and what is inside MetaMask may become out of sync after the chain restarts. So the advantage of this local wallet built into the app is this.
It works right in the browser, so you don't have to worry about it , and you can get funds right out of the tap by just clicking this little button. And you will see that your balance starts to replenish. So, now I have one ETH and I can start experimenting with it . Next we can go to the Debug Contracts tab, which is also very useful. This tab is a visual representation of your smart your smart contract.
So you can instantly see what the contract does. There is a greeting there. There is an owner there. There is a boolean value and a counter that tracks when the greeting changes. So we can instantly write, for example, " write, for example, " Hello Lisbon."
If I could still write correctly, like this, and send it, then the status would be updated. Yes? So we made it, and you can see that our balance went down because we paid some gas, right? And if we look inside the ETH scaffold itself, we will see several folders that are worth knowing about. One is the “chain” folder, and inside it are the contracts.
So, again, this is like your initial contract. You know, when you start using AI, we could just do a simple query here. Let's try to do something, I don't know, very simple. Well, let's turn this into a basic basic lottery smart contract or something like that. Let's see if he can do it.
And you'll see that we're using agents inside of this, as well as a "claude" folder and a "cursor" folder. What's cool here is that these are all the skills you need to properly develop on Ethereum, and they're already loaded for you. So if you use the ETH scaffold, they come by default. If you are using cloud code and want to start from scratch, this is where you need to go into ETH skills and copy them manually. But with the ETH scaffold, they are all already there.
For example, if you are building on X42, this is the skill for that . If you are creating a subgraph on the graph, this is a skill for that. If you use NFTTS, this is the skill. So it's like a default AI that will help guide the process because these skills are automatically loaded when you communicate. You see, here are all the details on how to work with Drizzle and Neon, right?
The same applies here. This is Carlos, one of the guys from build guild, about how to write smart contract code, what process to go through to make sure your smart your smart contract doesn't have any potential bugs or access control issues. These are kind of best practices that build guild has accumulated over time, and we have provided them to you in this area. So if you wanted to just grab them, you could get them directly from the GitHub repository, right? You could go here and see these three folders.
If you copied these three folders into your own project, it would also be able to work with AI properly. Let's see what happened here. Let's open our chat. So, he's trying to create certain features. We only have about five minutes, so let's see if he can build something interesting.
But now the process is underway, and he's changing the contract, right? He has already written a contract. He added Ownable. He added re-entry protection. He added a few variables.
He created a new constructor, new events, new errors. Uh, yes, he created a ticket purchase feature. He created a winner selection feature. Yes winner selection feature. Yes , it just makes all the changes for us, right?
So now we can go here and deploy these changes. It should work changes. It should work . Let's hope so. And again, Scaffold ETH will automatically pick up everything that the AI has done for you.
So, you can start testing. So now you see that we have a bunch of new variables. And you can notice that it didn't change anything in your interface, right? So now you want to say we will update the interface. So I can test it.
Now he has to process it and make any necessary changes. Let's see if he can do it. While we wait, maybe While we wait, maybe we can use these five minutes to answer a few questions. Does anyone have any questions at this point? No.
Yes. skill skill. Yes. Yes. You may have come late, but there is a website called eeskills.
com. Yes. Esskills.com is essentially a collaborative effort of many minds in the Ethereum community. We wrote this, and here is the main query, which you can copy, or just take these files just take these files , as I said, and put them in the appropriate folders.
So, depending on what you are using. If you use Cursor, it refers to the cursor folder. If it's Claude Code, it looks at the cloud folder. If you use other tools like ChatGPT etc., I think they use agents.
So you should put them in these folders. So, it's working now and creating an interface for us . Again , it will reference anything already in eeskills that is inherited by the standard environment. Was there any other question? While we wait.
No. Good. If you want to learn more about to learn more about why and how certain things work, I would recommend looking here, in the components. The components are pretty cool. You can see the Scaffold ETH style.
It is very simple but has many interesting features. Some of it looks like this, for example, you can copy the address and it will automatically convert to ENS and show the profile photo, right? It's a simple thing, but it's a reusable component available in scaffold-eth, and it shows exactly how to use it, right? The same applies to, for example, entering an address, right? You don't want people to just paste their text, so there's automatic ENS recognition inside this input field.
We also have a balance checker that checks the real ETH price and allows you to switch between them. Entering Ether so you can, for example, enter ETH and convert it to USDC or whatever. And hooks are, you could say, wrappers around your smart around your smart contract. This means contract. This means that if you want to perform a read function, it shows exactly how to do it.
You can simply say " simply say " use scaffold read contract", pass in the contract name, function, and arguments, and you'll get the data available in that object. Yes? So there are all these hooks for different things. Reading from a contract, writing to a contract, for example, using a real transaction, and there is an example to take an example from. In this example, it's a button: when you click it, it sets the greeting with the argument and passes 0.
1 ETH, and we use parse ether to convert. These are again just tips on how to use these hooks. But if you use AI, it should do it automatically because we programmed it to be very simple. Okay, that should work. Now let's take a look.
Wow, that's good. There is a separate page. Okay, of course. Let's check the lottery page. That's all.
So we have the opportunity to buy a ticket. That's it. Here we have a lottery ticket. And maybe we need to maybe we need to ...I don't know how to set the time.
Three minutes left. Oh, we won't have time . But, um, after 3 minutes, you know, one of the things you'll notice when you're working with time in a smart contract is that you need to, well, use a facet to simulate the passage of time, right? So if I sat here and waited two minutes and then did some mining, that would finally allow me to determine who won, right? Um, we could change this time or something, but okay, cool.
I think my time is almost up, but one last question. Someone? Yes. Foundry. Yes.
So, depending on what you're using, there's a test folder inside, and you can see that it comes with a basic test that follows the contract. So if you're using Hardhat, there will be a test folder, and they will all be written in JavaScript or TypeScript. If you use Foundry, they will be written in Solidity and you will see them here. And you can just do, for example, yarn test. Now it will give an error because it seems the test has not been updated.
Oh, never mind. So, he updated the test. Um, and that's it . Quite easy. So .
Quite easy. So , yarn and stuff. So, cool. OK. Thank you very much, guys.
I appreciate your time.
Automatic transcript — names and jargon may be misspelled.