#Deploying your contracts

To deploy your contracts, we recommend using Hardhat Ignition, our declarative deployment system. Hardhat Ignition is now the preferred method for deploying contracts in Hardhat v3.

In the sample project, you'll find an Ignition module for deploying the Lock contract. An Ignition module is a TypeScript or JavaScript file that specifies what needs to be deployed.

The LockModule which deploys the Lock contract is located in the ./ignition/modules directory and looks like this:

import { buildModule } from "@nomicfoundation/hardhat-ignition/modules";

const JAN_1ST_2030 = 1893456000;
const ONE_GWEI: bigint = 1_000_000_000n;

const LockModule = buildModule("LockModule", (m) => {
  const unlockTime = m.getParameter("unlockTime", JAN_1ST_2030);
  const lockedAmount = m.getParameter("lockedAmount", ONE_GWEI);

  const lock = m.contract("Lock", [unlockTime], {
    value: lockedAmount,
  });

  return { lock };
});

export default LockModule;

const { buildModule } = require("@nomicfoundation/hardhat-ignition/modules");

const JAN_1ST_2030 = 1893456000;
const ONE_GWEI = 1_000_000_000n;

module.exports = buildModule("LockModule", (m) => {
  const unlockTime = m.getParameter("unlockTime", JAN_1ST_2030);
  const lockedAmount = m.getParameter("lockedAmount", ONE_GWEI);

  const lock = m.contract("Lock", [unlockTime], {
    value: lockedAmount,
  });

  return { lock };
});

You can deploy in the localhost network following these steps:

1. Start a local node

   npx hardhat node
   

2. Open a new terminal and deploy the Hardhat Ignition module in the localhost network

   TypeScript

   JavaScript

   npx hardhat ignition deploy ./ignition/modules/Lock.ts --network localhost
   

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

As general rule, you can target any network from your Hardhat config using:

npx hardhat ignition deploy ./ignition/modules/Lock.js --network <your-network>

If no network is specified, Hardhat Ignition will run against an in-memory instance of Hardhat Network.

In the sample LockModule above, two module parameters are used: unlockTime which will default to the 1st of Jan 2030 and lockedAmount which will default to one Gwei. You can learn more about overriding these values by providing your own module parameters during deployment in our Deploying a module guide.

Hardhat Ignition, introduced in Hardhat v3, brings several improvements to the deployment process:

1. Declarative deployments: Define your entire deployment pipeline in a single, easy-to-understand module.
2. Built-in error handling and recovery: Automatically resume deployments from where they left off if interrupted.
3. Improved testability: Easily integrate deployments into your test suite.
4. Enhanced modularity: Create reusable deployment modules for different parts of your project.

Read more about Hardhat Ignition generally in the Hardhat Ignition documentation.