Deploy Your First Contract

This guide walks through deploying a smart contract to Igra using Hardhat or Foundry. Both work out of the box with no modifications.

Prerequisites

• Node.js 18+ (for Hardhat) or Foundry installed

• Testnet iKAS in your wallet (get some here)

• Private key for deployment

---

Option 1: Hardhat

Setup

mkdir igra-demo && cd igra-demo
npm init -y
npm install --save-dev hardhat @nomicfoundation/hardhat-toolbox
npx hardhat init

Select "Create a JavaScript project" when prompted.

Configure Network

Edit hardhat.config.js:

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

module.exports = {
  solidity: "0.8.24",
  networks: {
    igra_testnet: {
      url: "https://caravel.igralabs.com:8545",
      chainId: 19416,
      accounts: [process.env.PRIVATE_KEY],
    },
    igra_mainnet: {
      url: "https://brigantine.igralabs.com:8545",
      chainId: 0, // TBD - update when mainnet launches
      accounts: [process.env.PRIVATE_KEY],
    },
  },
};

Write Contract

Create contracts/HelloIgra.sol:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

contract HelloIgra {
    string public message;

    event MessageChanged(string oldMessage, string newMessage);

    constructor(string memory _message) {
        message = _message;
    }

    function setMessage(string memory _message) public {
        string memory oldMessage = message;
        message = _message;
        emit MessageChanged(oldMessage, _message);
    }
}

Deploy Script

Create scripts/deploy.js:

const hre = require("hardhat");

async function main() {
  const HelloIgra = await hre.ethers.getContractFactory("HelloIgra");
  const hello = await HelloIgra.deploy("Hello from Igra!");

  await hello.waitForDeployment();

  console.log("HelloIgra deployed to:", await hello.getAddress());
}

main().catch((error) => {
  console.error(error);
  process.exitCode = 1;
});

Deploy

export PRIVATE_KEY=your_private_key_here
npx hardhat run scripts/deploy.js --network igra_testnet

Output:

HelloIgra deployed to: 0x...

Verify Contract

npx hardhat verify --network igra_testnet CONTRACT_ADDRESS "Hello from Igra!"

Add to hardhat.config.js for verification:

module.exports = {
  // ... existing config
  etherscan: {
    apiKey: {
      igra_testnet: "no-api-key-needed",
    },
    customChains: [
      {
        network: "igra_testnet",
        chainId: 19416,
        urls: {
          apiURL: "https://explorer.caravel.igralabs.com/api",
          browserURL: "https://explorer.caravel.igralabs.com",
        },
      },
    ],
  },
};

---

Option 2: Foundry

Setup

mkdir igra-demo && cd igra-demo
forge init

Configure Network

Create or edit foundry.toml:

[profile.default]
src = "src"
out = "out"
libs = ["lib"]
solc = "0.8.24"

[rpc_endpoints]
igra_testnet = "https://caravel.igralabs.com:8545"
igra_mainnet = "https://brigantine.igralabs.com:8545"

[etherscan]
igra_testnet = { key = "no-api-key-needed", url = "https://explorer.caravel.igralabs.com/api" }

Write Contract

Create src/HelloIgra.sol:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

contract HelloIgra {
    string public message;

    event MessageChanged(string oldMessage, string newMessage);

    constructor(string memory _message) {
        message = _message;
    }

    function setMessage(string memory _message) public {
        string memory oldMessage = message;
        message = _message;
        emit MessageChanged(oldMessage, _message);
    }
}

Deploy

forge create --rpc-url igra_testnet \
  --private-key $PRIVATE_KEY \
  src/HelloIgra.sol:HelloIgra \
  --constructor-args "Hello from Igra!"

Output:

Deployer: 0x...
Deployed to: 0x...
Transaction hash: 0x...

Verify Contract

forge verify-contract CONTRACT_ADDRESS \
  src/HelloIgra.sol:HelloIgra \
  --chain-id 19416 \
  --verifier blockscout \
  --verifier-url https://explorer.caravel.igralabs.com/api \
  --constructor-args $(cast abi-encode "constructor(string)" "Hello from Igra!")

---

Interact with Your Contract

Using Hardhat Console

npx hardhat console --network igra_testnet

const HelloIgra = await ethers.getContractFactory("HelloIgra");
const hello = HelloIgra.attach("YOUR_CONTRACT_ADDRESS");

await hello.message();
// 'Hello from Igra!'

await hello.setMessage("Updated message");
await hello.message();
// 'Updated message'

Using Cast (Foundry)

# Read message
cast call CONTRACT_ADDRESS "message()(string)" --rpc-url igra_testnet

# Write message
cast send CONTRACT_ADDRESS "setMessage(string)" "New message" \
  --rpc-url igra_testnet \
  --private-key $PRIVATE_KEY

---

Things to Note

Fast confirmations: Transactions confirm in under 1 second. You will see your deployment almost instantly.

Low fees: Gas costs are minimal. The base fee is 1 wei.

Standard EVM: Any Solidity or Vyper contract that works on Ethereum will work on Igra without changes.

Transaction size: Keep deployment bytecode under 21 KB. Large contracts may need to be split.

---

Next Steps

• Network Info - RPC endpoints and chain parameters

• Ethereum Compatibility - Differences from Ethereum

• Architecture Overview - How Igra works under the hood