Quickstart

This guide will walk you through setting up your project, creating a smart account directly from a local key (without the embedded wallet widget), and executing a transaction.

We will use the @0xgasless/smart-account package and viem.

Prerequisites

• Node.js installed
• A package manager (npm, yarn, pnpm, or bun)
• An API key from the 0xGasless Dashboard

1. Setup Your Project

Create a new directory and initialize the project:

mkdir my-smart-account-app
cd my-smart-account-app
npm init -y

Install the dependencies:

npm install viem @0xgasless/smart-account
npm install --save-dev typescript @types/node ts-node

Create a tsconfig.json:

npx tsc --init

Update your package.json to allow ES modules:

{
  "name": "my-smart-account-app",
  "version": "1.0.0",
  "type": "module",
  "scripts": {
    "start": "ts-node src/index.ts"
  }
}

2. Initialize the Account

Create a src directory and an index.ts file inside it. Add the following code to initialize the smart account signer using a local private key.

Note: Never commit private keys to GitHub. We use a hardcoded one here for demonstration purposes, but you should use environment variables (process.env.PRIVATE_KEY) in production.

import { createSmartAccountClient } from "@0xgasless/smart-account";
import { privateKeyToAccount } from "viem/accounts";
import { parseAbi, encodeFunctionData } from "viem";

const API_KEY = "YOUR_API_KEY"; // Replace with your actual key
const BUNDLER_URL = "https://bundler.0xgasless.com/11155111"; // Sepolia
const PAYMASTER_URL = `https://paymaster.0xgasless.com/v1/11155111/rpc/${API_KEY}`;

// Generate a random local key for testing
const EOA = privateKeyToAccount("0x...");

async function main() {
  console.log("Setting up smart account...");

  // Create the smart account client
  const smartAccount = await createSmartAccountClient({
    signer: EOA,
    bundlerUrl: BUNDLER_URL,
    paymasterUrl: PAYMASTER_URL,
    chainId: 11155111,
  });

  const address = await smartAccount.getAddress();
  console.log("Smart Account deployed (or counterfactual) address:", address);

3. Execute a Transaction

Let’s mint a free NFT on Sepolia to test our gasless setup.

  console.log("Preparing transaction...");

  const nftContractAddress = "0xYourTestNFTAddress"; // Replace with a verifiable testnet contract
  const abi = parseAbi(["function safeMint(address to)"]);

  // Encode the contract call
  const callData = encodeFunctionData({
    abi,
    functionName: "safeMint",
    args: [address], // Minting the NFT to the smart account itself
  });

  console.log("Sending UserOperation to the Bundler...");

  const userOpResponse = await smartAccount.sendTransaction({
    to: nftContractAddress,
    data: callData,
    value: 0n,
  });

  const hash = await userOpResponse.waitForTxHash();
  console.log("UserOperation Hash:", hash);

  const receipt = await userOpResponse.wait();
  console.log("Transaction mined! Receipt:", receipt.receipt.transactionHash);
}

main().catch(console.error);

4. Run it

Execute the script:

npm start

If successful, you will see the smart account address and the transaction hash logged to your console. Since we provided a paymasterUrl, the user pays zero gas — 0xGasless sponsors it through your Paymaster policy.

Next Steps

• Learn how Bundlers process these UserOperations.
• Understand how Paymasters sponsor the transactions you just sent.