viem Compatibility

Overview

The CDP SDK is compatible with viem in a couple ways:

1. viem Local Accounts can be set as the owner of a CDP Smart Account. See the Signer Example below.
2. CDP accounts can be wrapped into viem Custom Accounts using the toAccount function. See the Wallet Client Example below.

Signer Example

You can create a viem Local Account and set it as the owner of a CDP Smart Account.

main.ts

import { CdpClient } from "@coinbase/cdp-sdk";
import { generatePrivateKey, privateKeyToAccount } from "viem/accounts";
import dotenv from "dotenv";

dotenv.config();

const cdp = new CdpClient();

const privateKey = generatePrivateKey();
const owner = privateKeyToAccount(privateKey);

const smartAccount = await cdp.evm.createSmartAccount({ owner });

Wallet Client Example

You can pass a CDP account to the toAccount function and get back a viem Custom Account, which can be used wherever viem expects an account. For example, you can create a viem Wallet Client from this account and use the Wallet Client to send transactions.

The following code snippet demonstrates how to use a viem Wallet Client to send a transaction.

If you followed the quickstart, you will have a project that you can use to follow along with the example below.

1. Install viem

Install viem in your project:

npm install viem

2. Create a Wallet Client from a CDP account

Here we use toAccount from viem/accounts to wrap a CDP account in a viem Custom Account, which is immediately passed to the createWalletClient function to create a viem Wallet Client.

main.ts

import { CdpClient } from "@coinbase/cdp-sdk";

import { createWalletClient } from "viem";
import { toAccount } from "viem/accounts";
import { baseSepolia } from "viem/chains";
import dotenv from "dotenv";

dotenv.config();

const cdp = new CdpClient();

const account = await cdp.evm.createAccount();
console.log("Created account:", account.address);

const walletClient = createWalletClient({
  account: toAccount(account),
  chain: baseSepolia,
  transport: http(),
});

3. Send a transaction with the Wallet Client

Next, use the Wallet Client to send a transaction, after requesting some testnet ETH from the faucet.

main.ts

import { http, createPublicClient, parseEther } from "viem";
import dotenv from "dotenv";

dotenv.config();

const cdp = new CdpClient();

// ... existing code ...

// This is used to wait for transaction confirmation
const publicClient = createPublicClient({
  chain: baseSepolia,
  transport: http(),
});

console.log("Requesting testnet ETH from faucet...");
const { transactionHash: faucetTransactionHash } = await cdp.evm.requestFaucet({
  address: account.address,
  network: "base-sepolia",
  token: "eth",
});

console.log("Waiting for funds to arrive...");
const faucetTxReceipt = await publicClient.waitForTransactionReceipt({
  hash: faucetTransactionHash,
});
console.log("Received testnet ETH");

const hash = await walletClient.sendTransaction({
  to: "0x0000000000000000000000000000000000000000",
  value: parseEther("0.000001"),
});

const txReceipt = await publicClient.waitForTransactionReceipt({
  hash,
});
console.log(
  `Transaction sent! Link: https://sepolia.basescan.org/tx/${hash}`
);

4. Putting it all together

Here’s the complete code for the example above.

main.ts

import { CdpClient } from "@coinbase/cdp-sdk";
import dotenv from "dotenv";
import { createWalletClient, http, createPublicClient, parseEther } from "viem";
import { toAccount } from "viem/accounts";
import { baseSepolia } from "viem/chains";

dotenv.config();
const cdp = new CdpClient();

const account = await cdp.evm.createAccount();
console.log("Created account:", account.address);

const walletClient = createWalletClient({
  account: toAccount(account),
  chain: baseSepolia,
  transport: http(),
});

// This is used to wait for transaction confirmation
const publicClient = createPublicClient({
  chain: baseSepolia,
  transport: http(),
});

console.log("Requesting testnet ETH from faucet...");
const { transactionHash: faucetTransactionHash } = await cdp.evm.requestFaucet({
  address: account.address,
  network: "base-sepolia",
  token: "eth",
});

console.log("Waiting for funds to arrive...");
const faucetTxReceipt = await publicClient.waitForTransactionReceipt({
  hash: faucetTransactionHash,
});
console.log("Received testnet ETH");

const hash = await walletClient.sendTransaction({
  to: "0x0000000000000000000000000000000000000000",
  value: parseEther("0.000001"),
});

const txReceipt = await publicClient.waitForTransactionReceipt({
  hash,
});
console.log(
  `Transaction sent! Link: https://sepolia.basescan.org/tx/${hash}`
);

What to read next

• v2 Wallet Accounts: Read more about the types of accounts and networks we support.
• viem: Learn from the official docs on how to get started developing with viem.