Deploying Smart Contracts

In this tutorial, you'll learn how to compile and deploy a Solidity smart contract to the Beatoz blockchain.

Project Setup

Step 1: Create Project Directory

mkdir beatoz-contract-demo
cd beatoz-contract-demo
npm init -y

Step 2: Install Dependencies

npm install @beatoz/web3 hardhat dotenv
npm install --save-dev @nomicfoundation/hardhat-toolbox

Step 3: Initialize Hardhat

npx hardhat init

Select "Create an empty hardhat.config.js" when prompted.

Writing Your First Contract

Testnet

SimpleStorage Contract

Create contracts/SimpleStorage.sol:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

contract SimpleStorage {
    uint256 private storedValue;
    
    event ValueChanged(uint256 oldValue, uint256 newValue);
    
    constructor(uint256 initialValue) {
        storedValue = initialValue;
    }
    
    function set(uint256 newValue) public {
        uint256 oldValue = storedValue;
        storedValue = newValue;
        emit ValueChanged(oldValue, newValue);
    }
    
    function get() public view returns (uint256) {
        return storedValue;
    }
}

Configure Hardhat

Update hardhat.config.js:

require("@nomicfoundation/hardhat-toolbox");

module.exports = {
  solidity: "0.8.19",
  paths: {
    sources: "./contracts",
    artifacts: "./artifacts",
  },
};

Compile the Contract

npx hardhat compile

Deploy Script

Create scripts/deploy.js:

const { Web3 } = require('@beatoz/web3');
const fs = require('fs');
const path = require('path');
require('dotenv').config();

async function main() {
  // Connect to Beatoz Testnet
  const web3 = new Web3('https://rpc-testnet0.beatoz.io');
  
  // Load deployer account
  const deployer = web3.beatoz.accounts.privateKeyToAccount(
    process.env.PRIVATE_KEY
  );
  console.log('Deployer:', deployer.address);

  const balance = await web3.beatoz.getBalance(deployer.address);
  console.log('Balance:', web3.utils.fromFons(balance, 'beatoz'), 'BTZ');
  
  // Load compiled contract
  const artifactPath = path.join(
    __dirname,
    '../artifacts/contracts/SimpleStorage.sol/SimpleStorage.json'
  );
  const artifact = JSON.parse(fs.readFileSync(artifactPath, 'utf-8'));

  const status = await web3.beatoz.status();
  const chainId = status.node_info.network;
  const contract = new web3.beatoz.Contract(artifact.abi);

  // Constructor argument: SimpleStorage(42)
  const result = await contract
    .deploy(artifact.bytecode, [42], deployer, chainId, 3_000_000)
    .send();
  
  console.log('✅ Contract deployed successfully!');
  console.log('Contract Address:', result.contractAddress);
  console.log('Transaction Hash:', result.hash);
  console.log('Block Height:', result.height);
  
  return result.contractAddress;
}

main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

Environment Setup

Create .env file:

PRIVATE_KEY=your_private_key_here

Deploy to Testnet

node scripts/deploy.js

Expected output:

Deployer: 0x1234...
✅ Contract deployed successfully!
Contract Address: 0xabcd...
Transaction Hash: 0x5678...
Block Height: 12345

Using the Contract Class

The deploy script above uses the Contract class exposed by @beatoz/web3:

const contract = new web3.beatoz.Contract(abi);
const result = await contract
  .deploy(bytecode, constructorArguments, deployerAccount, chainId, gasLimit)
  .send();

console.log(result.contractAddress);

Verify Deployment

After deployment, verify your contract is working:

async function verifyDeployment(contractAddress) {
  const web3 = new Web3('https://rpc-testnet0.beatoz.io');
  
  const contract = new web3.beatoz.Contract(abi, contractAddress);
  
  // Call the get() function
  const value = await contract.methods.get().call();
  console.log('Stored value:', value); // Should print 42
}

Complete Project Structure

beatoz-contract-demo/
├── contracts/
│   └── SimpleStorage.sol
├── scripts/
│   └── deploy.js
├── artifacts/          # Generated by Hardhat
├── .env
├── .gitignore
├── hardhat.config.js
└── package.json

Troubleshooting

"Insufficient balance"

Get tokens from the Faucet before deploying.

"Out of gas"

Increase the gas limit in your deployment script.

"Invalid nonce"

Fetch the latest nonce before each transaction.

Next Steps

• Interacting with Contracts
• Creating ERC-20 Tokens
• Handling Contract Events