Zerodev Kernel Account API

This package contains ZeroDev's KernelV2 implementation of the @alchemy/aa-core BaseSmartContractAccount class defined in @alchemy/aa-core.

What is Kernel V2? Documentation

Getting started

Follow the instructions below to install the packages.

via yarn

yarn add @alchemy/aa-core @zerodevapp/sdk@alpha viem

via npm

npm i -s @alchemy/aa-core @zerodevapp/sdk@alpha viem

Example Usage to Interact with Kernel Accounts

Basic Usage

import {
  KernelSmartContractAccount,
  ZeroDevProvider,
  ECDSAValidator,
  type ValidatorMode,
} from "@zerodevapp/sdk@alpha";
import { PrivateKeySigner } from "@alchemy/aa-core";
import { polygonMumbai } from "viem/chains";

const KERNEL_ACCOUNT_FACTORY_ADDRESS =
  "0x5D006d3880645ec6e254E18C1F879DAC9Dd71A39";

// 1. define the EOA owner of the Smart Account
// This is just one exapmle of how to interact with EOAs, feel free to use any other interface
const owner = PrivateKeySigner.privateKeyToAccountSigner(PRIVATE_KEY);

// 2. Create a ZeroDev Provider
let ecdsaProvider = await ECDSAProvider.init({
  projectId, // zeroDev projectId
  owner,
  // Optional: pass the paymasterConfig to use the verifying paymaster
  // opts: {
  //     paymasterConfig: {
  //         policy: "VERIFYING_PAYMASTER"
  //     }
  // }
});

// 3. send a UserOperation
const { hash } = await ecdsaProvider.sendUserOperation({
  target: "0xTargetAddress",
  data: "0xcallData",
  value: 0n, // value: bigint or undefined
});

Pay gas in ERC20

ZeroDev currently supports:

• USDC
• PEPE (mainnet only)
• DAI (upcoming)

Just pass the paymasterConfig to createZeroDevProvider function while creating the provider.

let ecdsaProvider = await ECDSAProvider.init({
  projectId, // zeroDev projectId
  owner,
  opts: {
    paymasterConfig: {
      policy: "TOKEN_PAYMASTER",
      gasToken: "TEST_ERC20",
    },
  },
});

Change Kernel Account Owner in ECDSAValidator

// 1. Create a ECDSAValidatorProvider
const ecdsaProvider = await ECDSAProvider.init({
    projectId: "c73037ef-8c0b-48be-a581-1f3d161151d3",
    owner,
});

// 2. Change the owner of the Kernel Account
const { hash } = await ecdsaProvider.changeOwner(<NEW_OWNER_ADDRESS>);

Via ethers

import { Wallet } from "@ethersproject/wallet";
import {
  ZeroDevEthersProvider,
  convertWalletToAccountSigner,
} from "@zerodevapp/sdk@alpha";

// 1. Create an ethers Wallet
const owner = Wallet.fromMnemonic(OWNER_MNEMONIC);

// 2. Create a ZeroDev ZeroDevEthersProvider passing the ethers Wallet as the signer
const provider = await ZeroDevEthersProvider.init("ECDSA", {
  projectId, // zeroDev projectId
  owner: convertWalletToAccountSigner(owner),
  opts: {
    paymasterConfig: {
      policy: "VERIFYING_PAYMASTER",
    },
  },
});

// 3. Get the AccountSigner adapter of ethers signer
const signer = provider.getAccountSigner();

// 4. send a UserOperation
const { hash } = signer.sendUserOperation({
  target: "0xTargetAddress",
  data: "0xcallData",
  value: 0n, // value: bigint or undefined
});

Via viem using custom transport which supports EIP-1193 providers

import { createWalletClient, custom } from "viem";
import { polygonMumbai } from "viem/chains";
import {
  ECDSAProvider,
  convertWalletClientToAccountSigner,
} from "@zerodevapp/sdk@alpha";

// 1. Create a Viem Wallet Client using the custom transport
const client = createWalletClient({
  chain: polygonMumbai,
  transport: custom(window.ethereum),
});

// 2. Create a ZeroDev ECDSAProvider passing the Viem Wallet Client as the signer
let ecdsaProvider = await ECDSAProvider.init({
  projectId, // zeroDev projectId
  owner: convertWalletClientToAccountSigner(client),
});

// 3. send a UserOperation
const { hash } = await ecdsaProvider.sendUserOperation({
  target: "0xTargetAddress",
  data: "0xcallData",
  value: 0n, // value: bigint or undefined
});

Using Magic

import { ECDSAProvider, getRPCProviderOwner } from "@zerodevapp/sdk@alpha";
import { Magic } from "magic-sdk";

const magic = new Magic("MAGIC_API_KEY", {
  // magic config...
});

let ecdsaProvider = await ECDSAProvider.init({
  projectId, // zeroDev projectId
  owner: getRPCProviderOwner(magic.rpcProvider),
});

Using Web3Auth

import { ECDSAProvider, getRPCProviderOwner } from "@zerodevapp/sdk@alpha";
import { Web3Auth } from "@web3auth/modal";

const web3auth = new Web3Auth({
  // web3auth config...
});

await web3auth.initModal();

web3auth.connect();

let ecdsaProvider = await ECDSAProvider.init({
  projectId, // zeroDev projectId
  owner: getRPCProviderOwner(web3auth.provider),
});

Components

Core Components

The primary interfaces are the ZeroDevProvider, KernelSmartContractAccount and KernelBaseValidator

The ZeroDevProvider is an ERC-1193 compliant Provider built on top of Alchemy's SmartAccountProvider

1. sendUserOperation -- this takes in target, callData, and an optional value which then constructs a UserOperation (UO), sends it, and returns the hash of the UO. It handles estimating gas, fetching fee data, (optionally) requesting paymasterAndData, and lastly signing. This is done via a middleware stack that runs in a specific order. The middleware order is getDummyPaymasterData => estimateGas => getFeeData => getPaymasterAndData. The paymaster fields are set to 0x by default. They can be changed using provider.withPaymasterMiddleware.
2. sendTransaction -- this takes in a traditional Transaction Request object which then gets converted into a UO. Currently, the only data being used from the Transaction Request object is from, to, data and value. Support for other fields is coming soon.

KernelSmartContractAccount is Kernel's implementation of BaseSmartContractAccount. 6 main methods are implemented

1. getDummySignature -- this method should return a signature that will not revert during validation. It does not have to pass validation, just not cause the contract to revert. This is required for gas estimation so that the gas estimate are accurate.
2. encodeExecute -- this method should return the abi encoded function data for a call to your contract's execute method
3. encodeExecuteDelegate -- this method should return the abi encoded function data for a delegate call to your contract's execute method
4. signMessage -- this is used to sign UO Hashes
5. signWithEip6492 -- this should return an ERC-191 and EIP-6492 compliant message used to personal_sign
6. getAccountInitCode -- this should return the init code that will be used to create an account if one does not exist. Usually this is the concatenation of the account's factory address and the abi encoded function data of the account factory's createAccount method.

The KernelBaseValidator is a plugin that modify how transactions are validated. It allows for extension and implementation of arbitrary validation logic. It implements 3 main methods:

1. getAddress -- this returns the address of the validator
2. getOwner -- this returns the eligible signer's address for the active smart wallet
3. getSignature -- this method signs the userop hash using signer object and then concats additional params based on validator mode.

Contributing

1. clone the repo
2. run yarn
3. Make changes to packages