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Send your first transaction

Introduction​

In this tutorial, you will learn how to submit your first transaction using a smart contract wallet. You'll be guided through setting up the necessary client with @fuseio/fusebox-web-sdk, creating a user operation, obtaining sponsorship from FuseBox's verifying paymaster, and finally submitting it on-chain using FuseBox's bundler.

Obtain an API Key​

To begin, navigate to our Operator Dashboard and generate an API key. This key is essential for accessing our services.

Clone the FuseBox Tutorial Template Repository​

To facilitate your start, we've prepared a FuseBox tutorial template repository equipped with Typescript, viem, and @fuseio/fusebox-web-sdk. Follow these steps to clone the repository and set up your environment:

git clone https://github.com/fuseio/tutorial-template.git fusebox-tutorial
cd fusebox-tutorial

Proceed by installing the dependencies:

npm install

We'll mainly work with the index.ts file. Test your setup by running:

npm start

If set up correctly, you should see Hello world! printed in the console.

Generate a Private Key​

Generate a private key and store it securely. Use the following code snippet in index.ts:

const privateKey =
  process.env.PRIVATE_KEY ??
  (() => {
    const pk = generatePrivateKey();
    writeFileSync(".env", `PRIVATE_KEY=${pk}`);
    return pk;
  })();

Initialize the SDK​

FuseSDK enables the creation of User Operations for ERC-4337 Etherspot Smart Account, Bundler service, or Paymaster. It's open source and MIT licensed, offering flexibility and no lock-in. Replace YOUR_FUSEBOX_API_KEY with your actual API key:

const apiKey = "YOUR_FUSEBOX_API_KEY";
const credentials = new ethers.Wallet(privateKey);
const fuseSDK = await FuseSDK.init(apiKey, credentials);

Create a smart contract wallet​

Initialize the SDK with the previously generated private key to create the Etherspot Smart Account:

console.log(
  `Smart account address: https://explorer.fuse.io/address/${fuseSDK.wallet.getSender()}`
);

Running this code will display the smart account address in the console. Note that the smart account is counterfactual and will be deployed on-chain when you send a transaction.

Submit a Transaction​

Now, let's submit a transaction from the smart account. We'll send a transaction to 0xd8da6bf26964af9d7eed9e03e53415d37aa96045 (vitalik.eth) with 0x1234 as example call data. FuseSDK will handle the operations (but you need to fund the account with some FUSE yourself first):

const to = "0xd8da6bf26964af9d7eed9e03e53415d37aa96045"; // for vitalik.eth
const value = ethers.utils.parseEther("0");
const data = new TextEncoder().encode("0x1234");
const res = await fuseSDK.callContract(to, value, data);

console.log(`UserOpHash: ${res?.userOpHash}`);
console.log("Waiting for transaction...");

const receipt = await res?.wait();

console.log(
  `User operation included: https://explorer.fuse.io/tx/${receipt?.transactionHash}`
);

Upon running, you'll see the transaction hash and confirmation that your operation is on-chain.

Congratulations! You've successfully sent a transaction, deploying a smart account, verifying its signature, having the operation sponsored, and executing a transaction—all with just a few lines of code.

For any questions or to share your projects, please contact us.