Deploy with Hardhat

Deploying a Counter Contract with Hardhat

This guide will walk you through deploying a counter contract using Hardhat, a popular JavaScript-based development environment for Ethereum.

1. Prerequisites

Before you begin, ensure you have:

• Node.js installed (v12 or later)

• npm (comes with Node.js)

• A code editor (e.g., VS Code)

• MetaMask wallet and testnet tokens for deployment

2. Install Hardhat

Open your terminal and create a new project directory:

mkdir counter-project
cd counter-project

Initialize a new npm project:

npm init -y

Install Hardhat and required dependencies:

npm install --save-dev hardhat @nomicfoundation/hardhat-toolbox dotenv

npm install --save-dev @nomicfoundation/hardhat-ignition

3. Create a New Hardhat Project

Run the Hardhat setup wizard:

npx hardhat

Choose “Create a JavaScript project” when prompted.

This will create a project structure like:

• contracts/ - for Solidity contracts

• igntion/ - for deployment scripts

• test/ - for tests

• hardhat.config.js - configuration file

4. Write Your Smart Contract

Create a new file in the contracts directory, Counter.sol:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
contract Counter { 
uint256 private count;   
function increment() public {        
count += 1;    
}     
function decrement() public {        
count -= 1;    
}     
function getCount() public view returns (uint256) {        
return count;    
}
}

5. Compile the Smart Contract

Compile your contracts with:

npx hardhat compile

You should see a success message if there are no errors.

6. Write a Deployment Script

Create a new file in the ignition directory, Counter.js:

const { buildModule } = require("@nomicfoundation/hardhat-ignition/modules"); module.exports = buildModule("CounterModule", (m) => { 
const counter = m.contract("Counter"); 
return { counter };
});

7. Configure Network Settings

Create a .env file in your project root:

PRIVATE_KEY=your_private_key_here

Edit hardhat.config.js:

require("@nomicfoundation/hardhat-toolbox");
require("dotenv").config(); 
module.exports = {  
solidity: "0.8.28",  
networks: {    
hardhat: {      
chainId: 31337,    
},    
lazai: {      
url: "https://lazai-testnet.metisdevops.link",      
chainId: 133718,      
accounts: [process.env.PRIVATE_KEY],    
},  
},
};

8. Deploy Your Contract

Local Deployment (Optional)

Start the Hardhat local node in a separate terminal:

npx hardhat node

Deploy to local network:

npx hardhat ignition deploy ignition/modules/Counter.js --network  localhost

Deploy to LazAI Testnet

Make sure to:

1. Get testnet tokens from the faucet

2. Add your private key to the .env file

3. Never share your private key

Deploy to LazAI:

npx hardhat ignition deploy ignition/modules/Counter.js --network lazai

Test Setup

Create test/Counter.js:

const { expect } = require("chai"); 
describe("Counter", function () {  
it("Should increment the counter", async function () {  
const Counter = await ethers.getContractFactory("Counter");    
const counter = await Counter.deploy();    
await counter.deployed();     
await counter.increment();    
expect(await counter.getCount()).to.equal(1);
});
});

Running Tests

npx hardhat test