Migration Guide

If you are coming from an earlier version of viem, you will need to make sure to update the following APIs listed below.

0.2.x Breaking changes

`chain` is required for `sendTransaction`, `writeContract`, `deployContract`

A chain is now required for the sendTransaction, writeContract, deployContract Actions.

You can hoist the Chain on the Client:

import { createWalletClient, custom, getAccount } from 'viem'
import { mainnet } from 'viem/chains'

export const walletClient = createWalletClient({
  chain: mainnet, 
  transport: custom(window.ethereum)
})
 
const account = getAccount('0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266')
 
const hash = await walletClient.sendTransaction({ 
  account,
  to: '0x70997970c51812dc3a010c7d01b50e0d17dc79c8',
  value: 1000000000000000000n
})

Alternatively, you can pass the Chain directly to the Action:

import { createWalletClient, custom, getAccount } from 'viem'
import { mainnet } from 'viem/chains'

export const walletClient = createWalletClient({
  chain: mainnet, 
  transport: custom(window.ethereum)
})
 
const account = getAccount('0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266')
 
const hash = await walletClient.sendTransaction({ 
  account,
  chain: mainnet, 
  to: '0x70997970c51812dc3a010c7d01b50e0d17dc79c8',
  value: 1000000000000000000n
})

`recoverAddress`, `recoverMessageAddress`, `verifyMessage` are now async

he following functions are now async functions instead of synchronous functions:

recoverAddress
recoverMessageAddress
verifyMessage

import { recoverMessageAddress } from 'viem'

recoverMessageAddress({ message: 'hello world', signature: '0x...' }) 
await recoverMessageAddress({ message: 'hello world', signature: '0x...' })

`assertChain` removed from `sendTransaction`

Removed assertChain argument on sendTransaction, writeContract & deployContract. If you wish to bypass the chain check (not recommended unless for testing purposes), you can pass chain: null.

await walletClient.sendTransaction({
  assertChain: false, 
  chain: null, 
  ...
})

`getAccount` removed

Removed the getAccount function.

For JSON-RPC Accounts, use the address itself.

You can now pass the address directly to the account option.

import { createWalletClient, custom } from 'viem'
import { mainnet } from 'viem/chains'

const address = '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2'

const client = createWalletClient({
  account: getAccount(address), 
  account: address, 
  chain: mainnet,
  transport: custom(window.ethereum)
})

For Ethers Wallet Adapter, use `ethersWalletToAccount`.

If you were using the Ethers Wallet adapter, you can use the ethersWalletToAccount function.

Note: viem 0.2.0 now has a Private Key & Mnemonic Account implementation. You probably do not need this adapter anymore. This adapter may be removed in a future version.

import { createWalletClient, custom } from 'viem'
import { mainnet } from 'viem/chains'
import { getAccount } from 'viem/ethers' 
import { ethersWalletToAccount } from 'viem/ethers' 
import { Wallet } from 'ethers'

const account = getAccount(new Wallet('0x...')) 
const account = ethersWalletToAccount(new Wallet('0x...')) 

const client = createWalletClient({
  account,
  chain: mainnet,
  transport: custom(window.ethereum)
})

For Local Accounts, use `toAccount`.

If you are using a custom signing implementation, you can use the toAccount function.

import { createWalletClient, http, getAccount } from 'viem' 
import { createWalletClient, http } from 'viem' 
import { toAccount } from 'viem/accounts' 
import { mainnet } from 'viem/chains'
import { getAddress, signMessage, signTransaction } from './sign-utils' 

const privateKey = '0x...' 
const account = getAccount({ 
const account = toAccount({ 
  address: getAddress(privateKey),
  signMessage(message) {
    return signMessage(message, privateKey)
  },
  signTransaction(transaction) {
    return signTransaction(transaction, privateKey)
  },
  signTypedData(typedData) {
    return signTypedData(typedData, privateKey)
  }
})

const client = createWalletClient({
  account,
  chain: mainnet,
  transport: http()
})

`data` renamed in `signMessage`

Renamed the data parameter in signMessage to message.

walletClient.signMessage({
  data: 'hello world', 
  message: 'hello world', 
})

Migration Guide ​

0.2.x Breaking changes ​

chain is required for sendTransaction, writeContract, deployContract ​

recoverAddress, recoverMessageAddress, verifyMessage are now async ​

assertChain removed from sendTransaction ​

getAccount removed ​

For JSON-RPC Accounts, use the address itself. ​

For Ethers Wallet Adapter, use ethersWalletToAccount. ​

For Local Accounts, use toAccount. ​

data renamed in signMessage ​