hardhat

hardhat Best Practices

Hardhat 3 is the definitive standard for Ethereum development. These rules enforce a modern, secure, and efficient workflow leveraging its Rust runtime, TypeScript support, and robust testing tools.

1. Adopt Hardhat 3 Immediately

Migrate all projects to Hardhat 3. Its Rust-powered runtime offers superior performance, instant stack traces, and enhanced debugging. Hardhat 2 is deprecated for new development.

2. Standardized Project Configuration (hardhat.config.ts)

Always use TypeScript for your Hardhat configuration. Pin Solidity compiler versions, enable Solidity test conventions, and activate essential plugins.

✅ GOOD: hardhat.config.ts

import { HardhatUserConfig } from "hardhat/config";
import "@nomicfoundation/hardhat-toolbox"; // Includes Ethers, Chai, Verify, etc.
import "@nomicfoundation/hardhat-ignition";
import "hardhat-gas-reporter";
import "solidity-coverage";
import "@nomicfoundation/hardhat-solhint"; // For Solhint

const config: HardhatUserConfig = {
  solidity: {
    compilers: [
      { version: "0.8.20" }, // Pin specific, stable Solidity versions
      { version: "0.8.21" },
    ],
    settings: {
      optimizer: {
        enabled: true,
        runs: 200,
      },
    },
  },
  networks: {
    hardhat: {
      // Hardhat Network for local development and testing
      chainId: 31337,
    },
    // Example for a testnet:
    sepolia: {
      url: process.env.SEPOLIA_RPC_URL || "",
      accounts: process.env.PRIVATE_KEY !== undefined ? [process.env.PRIVATE_KEY] : [],
    },
  },
  paths: {
    sources: "./contracts",
    tests: "./test",
    cache: "./cache",
    artifacts: "./artifacts",
    // Enable Solidity test file convention (e.g., `contracts/MyContract.t.sol`)
    // This is the default, but explicitly setting it is good practice.
    // tests: { solidity: "./contracts" } // If you want .t.sol files in contracts/
  },
  gasReporter: {
    enabled: process.env.REPORT_GAS !== undefined,
    currency: "USD",
    coinmarketcap: process.env.COINMARKETCAP_API_KEY,
  },
  typechain: {
    outDir: "typechain-types",
    target: "ethers-v6", // Use ethers-v6 for modern projects
  },
  etherscan: {
    apiKey: process.env.ETHERSCAN_API_KEY,
  },
};

export default config;