Deploy with Hardhat

In this guide you deploy a contract to BOT Chain testnet with Hardhat Ignition, then read it back from a script.

Everything on this page uses testnet (chain 968). Get free test tokens from the faucet.

What you’ll build

An Ignition module that deploys Counter, a record of the deployment in your project, and a script that reads the deployed contract.

Prerequisites

A Hardhat 3 project set up for BOT Chain, including the fee hook. Follow Set up Hardhat first.
BOT_PRIVATE_KEY set in the Hardhat keystore or your terminal, for a wallet with at least 0.01 tBOT.
contracts/Counter.sol from the setup guide.

Steps

Write an Ignition module

An Ignition module describes what to deploy. Ignition works out the order and keeps a journal, so a failed deploy can resume where it stopped.

ignition/modules/Counter.ts

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

export default buildModule("CounterModule", (m) => {
  const counter = m.contract("Counter");
  return { counter };
});

If your contract takes constructor arguments, pass them as an array: m.contract("Greeter", ["Hello"]).

Deploy to testnet

npx hardhat ignition deploy ignition/modules/Counter.ts --network botTestnet

Ignition asks you to confirm the network. Type y. When it finishes you’ll see output like:

Output

[ CounterModule ] successfully deployed 🚀

Deployed Addresses

CounterModule#Counter - 0x24E48d0fcf9B5500EE3DD77f96d095Db090a9F58

Your address will be different. Ignition also saves it in ignition/deployments/chain-968/deployed_addresses.json.

Read the contract from a script

scripts/read-counter.ts

import { network } from "hardhat";

const counterAddress = process.env.COUNTER_ADDRESS;
if (!counterAddress) throw new Error("Set COUNTER_ADDRESS to your Counter address");

const { viem } = await network.getOrCreate();
const counter = await viem.getContractAt("Counter", counterAddress as `0x${string}`);
console.log(`count is ${await counter.read.count()}`);

COUNTER_ADDRESS=0xYOUR_COUNTER npx hardhat run scripts/read-counter.ts --network botTestnet

You should see count is 0.

Verify it worked

Run npx hardhat ignition status chain-968. It prints Deployment chain-968 (chainId: 968) was successful and the address.
Open https://scan.bohr.life/address/YOUR_ADDRESS. BOTScan shows the contract and the deploy transaction.

Next, verify the source so others can read it on BOTScan.

Deploy to mainnet

Mainnet deploys cost real BOT and can’t be undone. Test on testnet first and use a separate key for mainnet.

Use the same module with the mainnet network:

npx hardhat ignition deploy ignition/modules/Counter.ts --network botMainnet

Ignition stores mainnet deployments in ignition/deployments/chain-677.

Troubleshooting

transaction underpriced: effective gas tip 0, minimum needed 20000000000

Ignition sent a fee of 0 because BOT Chain’s base fee is 0. Add the fee hook from Set up Hardhat, then deploy again.

Ignition says a previous run failed or a transaction is pending

Ignition resumes from its journal. If the earlier run failed before anything was sent (for example, an RPC error), delete ignition/deployments/chain-968 and deploy again. Don’t delete it if a contract was deployed, or Ignition will deploy a second copy.

insufficient funds for gas

Your wallet needs tBOT. Check the address with the script in Set up Hardhat and claim from a faucet.

An RPC call returns 502

The public RPC sometimes drops a request. Run the same deploy command again; Ignition picks up where it stopped.

Development environment

Deploy and verify

Frontend

DeFi

Bridge

Gasless transactions

AI agents

Data and indexing

Deploy with Hardhat

What you’ll build

Prerequisites

Steps

Verify it worked

Deploy to mainnet

Troubleshooting

Next steps

Verify with Hardhat

Set up wagmi

​What you’ll build

​Prerequisites

​Steps

​Verify it worked

​Deploy to mainnet

​Troubleshooting

​Next steps

Verify with Hardhat

Set up wagmi

What you’ll build

Prerequisites

Steps

Verify it worked

Deploy to mainnet

Troubleshooting

Next steps