# Migration Guide (/advanced/migration) > For the complete documentation index, see [llms.txt](/llms.txt) ## API v2 => API v3 [#api-v2--api-v3] With API v3, the notable changes are: * A ZeroDev project can now support multiple networks. * The same RPC can be used for both bundler and paymaster. Here's what a v3 RPC looks like: ```txt https://rpc.zerodev.app/api/v3/xxxxxf2d-xxxx-xxxx-90cc-xxxxxxxxx007/chain/42161 ``` Note that the last part `42161` is the chain ID. Therefore, if you'd like to programmatically use the RPC for different chains, you can do something like: ```ts // replace the prefix with your own RPC prefix const rpcPrefix = `https://rpc.zerodev.app/api/v3/xxxxxf2d-xxxx-xxxx-90cc-xxxxxxxxx007/chain/` const rpc = rpcPrefix + chain.id ``` Of course, you can also simply copy the RPC for different chains from the dashboard.

The same RPC can then be used as both the bundler RPC and the paymaster RPC. See [the tutorial](/get-started/quickstart#creating-a-kernel-client) for an example. ## SDK 5.3.x => 5.4.x [#sdk-53x--54x] In version **5.4.x** of the `@zerodev/sdk`, we've migrated to using `viem@2.18.x` with native Account Abstraction (AA) modules instead of the `permissionless` package. This change brings significant updates to types, imports, function signatures, and overall API usage. This guide will help you migrate your codebase to be compatible with the new version. ### Update dependencies [#update-dependencies] 1. **Remove the `permissionless` package**: ```bash npm uninstall permissionless ``` 2. **Ensure you have `viem@^2.21.40` version** ### Update `permissionless` Account Abstractions [#update-permissionless-account-abstractions] Replace any imports from `permissionless` with the equivalent from `viem/account-abstraction` or `@zerodev/sdk` if applicable. ### Update Type Definitions [#update-type-definitions] Replace `EntryPoint` Types ```typescript import type { EntryPoint } from 'permissionless/types'; // [!code --] import type { EntryPointVersion } from 'viem/account-abstraction'; // [!code ++] ``` Replace `UserOperation` Types ```typescript import type { UserOperation } from 'permissionless/types'; // [!code --] import type { UserOperation } from 'viem/account-abstraction'; // [!code ++] ``` ### Replaced `entryPoint: Address` with `entryPoint: { address: Address; version: EntryPointVersion}` [#replaced-entrypoint-address-with-entrypoint--address-address-version-entrypointversion] For `createKernelAccount` and `signerToEcdsaValidator` among other plugins, replace the `entryPoint` parameter as shown: ```typescript import { getEntryPoint } from "@zerodev/sdk/constants"; // [!code ++] createKernelAccount(publicClient, { // ... entryPoint: ENTRYPOINT_ADDRESS_V07, // [!code --] entryPoint: getEntryPoint("0.7"), // [!code ++] }) ``` ```typescript signerToEcdsaValidator(publicClient, { // ... entryPoint: ENTRYPOINT_ADDRESS_V07, // [!code --] entryPoint: getEntryPoint("0.7"), // [!code ++] }) ``` ### Removed `entryPoint` from `createKernelAccountClient` [#removed-entrypoint-from-createkernelaccountclient] ```typescript const kernelClient = createKernelAccountClient({ entryPoint, // [!code --] // ... }); ``` ### Replaced `middleware.sponsorUserOperation` from `createKernelAccountClient` with `paymaster.getPaymasterData` [#replaced-middlewaresponsoruseroperation-from-createkernelaccountclient-with-paymastergetpaymasterdata] ```typescript const kernelClient = createKernelAccountClient({ middleware: { // [!code --] sponsorUserOperation: paymasterClient.sponsorUserOperation, // [!code --] }, // [!code --] paymaster: { // [!code ++] getPaymasterData(userOperation) { // [!code ++] return paymasterClient.sponsorUserOperation({ userOperation }) // [!code ++] } // [!code ++] } // [!code ++] // ... }); ``` ### Added `client` to `createKernelAccountClient` [#added-client-to-createkernelaccountclient] `client` is now required in `createKernelAccountClient`. ```typescript const kernelClient = createKernelAccountClient({ client: publicClient, // [!code ++] // ... }); ``` ### Added `estimateFeesPerGas` to `userOperation` in `createKernelAccountClient` [#added-estimatefeespergas-to-useroperation-in-createkernelaccountclient] `estimateFeesPerGas` is now required in `userOperation` in `createKernelAccountClient` to estimate the gas price for the user operation. The default gas prices might be too high, so it's recommended to use this function to estimate the gas price. ```typescript const kernelClient = createKernelAccountClient({ userOperation: { // [!code ++] estimateFeesPerGas: async ({bundlerClient}) => { // [!code ++] return getUserOperationGasPrice(bundlerClient) // [!code ++] } // [!code ++] }, // [!code ++] // ... }); ``` ### `kernelClient.sendUserOperation` and `kernelClient.signUserOperation` now take `userOperation` properties directly [#kernelclientsenduseroperation-and-kernelclientsignuseroperation-now-take-useroperation-properties-directly] ```typescript await kernelClient.sendUserOperation({ userOperation: { sender, callData, nonce, ...rest }, // [!code --] sender, // [!code ++] callData, // [!code ++] nonce, // [!code ++] ...rest // [!code ++] }); await kernelClient.signUserOperation({ userOperation: { sender, callData, nonce, ...rest }, // [!code --] sender, // [!code ++] callData, // [!code ++] nonce, // [!code ++] ...rest // [!code ++] }); ``` ### Replaced `account.encodeCallData` with `account.encodeCalls` [#replaced-accountencodecalldata-with-accountencodecalls] ```typescript await account.encodeCallData( // [!code --] { // [!code --] to: zeroAddress, // [!code --] value: BigInt(0), // [!code --] data: "0x", // [!code --] callType // [!code --] }, // [!code --] ), // [!code --] await account.encodeCalls([ // [!code ++] { // [!code ++] to: zeroAddress, // [!code ++] value: BigInt(0), // [!code ++] data: "0x", // [!code ++] }, // [!code ++] ], callType), // [!code ++] ``` ### Replaced `kernelClient.sendTransactions` with `kernelClient.sendTransaction` [#replaced-kernelclientsendtransactions-with-kernelclientsendtransaction] ```typescript await kernelClient.sendTransactions({ // [!code --] transactions: [ // [!code --] // ... // [!code --] ], // [!code --] }); // [!code --] await kernelClient.sendTransaction({ // [!code ++] calls: [ // [!code ++] // ... // [!code ++] ], // [!code ++] }); // [!code ++] ``` ### `KernelAccountClient` extends `bundlerActions` by default [#kernelaccountclient-extends-bundleractions-by-default] For example: ```typescript const bundlerClient = kernelClient.extend(bundlerActions(entryPoint)); // [!code --] await bundlerClient.waitForUserOperationReceipt({ // [!code --] hash: userOpHash, // [!code --] }); // [!code --] await kernelClient.waitForUserOperationReceipt({ hash }) // [!code ++] ``` ### Merged `bundlerClient.sendUserOperation` and `kernelClient.sendUserOperation` [#merged-bundlerclientsenduseroperation-and-kernelclientsenduseroperation] `kernelClient.sendUserOperation` now prepares the `userOperation` if needed and directly calls `eth_sendUserOperation`. ## SDK 5.1.x => 5.2.x [#sdk-51x--52x] ### Most functions now take an `entryPoint` param [#most-functions-now-take-an-entrypoint-param] EntryPoint 0.7 is the most recent update to ERC-4337, but we will still be supporting EntryPoint 0.6. The SDK will automatically use Kernel v3 for EntryPoint 0.7, and Kernel v2 for EntryPoint 0.6. You will need to specify an `entryPoint` parameter to many functions, including: * Functions for creating validators, such as `signerToEcdsaValidator` * Functions for creating Kernel accounts, such as `createKernelAccount` * Function for creating Kernel client: `createKernelAccountClient` For example: ```ts import { ENTRYPOINT_ADDRESS_V06, ENTRYPOINT_ADDRESS_V07 } from "permissionless" // If migrating a live app const entryPoint = ENTRYPOINT_ADDRESS_V06 // If launching a new app const entryPoint = ENTRYPOINT_ADDRESS_V07 const account = await createKernelAccount(publicClient, { plugins: { sudo: ecdsaValidator, }, entryPoint, }) ``` * If you are migrating a live app that is using EntryPoint 0.6 (Kernel v2), set `entryPoint` to `ENTRYPOINT_ADDRESS_V06`. * If you are launching a new app, set `entryPoint` to `ENTRYPOINT_ADDRESS_V07`. ### Replaced `transport` with `bundlerTransport` inside `createKernelAccountClient` [#replaced-transport-with-bundlertransport-inside-createkernelaccountclient] ```ts const kernelClient = createKernelAccountClient({ transport: http(bundlerUrl), // [!code --] bundlerTransport: http(bundlerUrl), // [!code ++] // ... }) ``` ### Replaced `sponsorUserOperation` with `middleware.sponsorUserOperation` [#replaced-sponsoruseroperation-with-middlewaresponsoruseroperation] Instead of accepting just a `sponsorUserOperation` middleware, `createSmartAccountClient` now accepts a `middleware` function that can specify a `sponsorUserOperation` function internally, as well as a `gasPrice` function. ```ts const kernelClient = createKernelAccountClient({ sponsorUserOperation: paymasterClient.sponsorUserOperation, // [!code --] middleware: { // [!code ++] sponsorUserOperation: paymasterClient.sponsorUserOperation, // [!code ++] }, // [!code ++] // ... }) ```