Use Lit Protocol with ZeroDev

Lit Protocol is distributed cryptography for signing, encryption, and compute. A generalizable key management network, Lit provides you with a set of tools for managing sovereign identities on the open Web.

Set up

To use Lit with ZeroDev, first create an application that integrates with Lit.

Refer to the Lit documentation site for instructions on setting up an application with the Lit.
For a quick start, Lit provides examples, available here.

Integration

Integrating ZeroDev with Lit is straightforward after setting up the project. Lit provides an Externally Owned Account (EOA) wallet to use as a signer with Kernel.

Create the pkpWallet

After following the Lit documentation, you will have access to a pkpWallet. An example is shown below:

import { LitAbility, LitActionResource } from "@lit-protocol/auth-helpers";
import { LitNodeClient } from "@lit-protocol/lit-node-client";
import { PKPEthersWallet } from "@lit-protocol/pkp-ethers";
import { AuthCallbackParams } from "@lit-protocol/types";
 
const POLYGON_MUMBAI_RPC_URL = "<YOUR RPC URL HERE>";
const PKP_PUBLIC_KEY = "<YOUR PKP PUBLIC KEY>";
 
const litNodeClient = new LitNodeClient({
  litNetwork: "cayenne",
  debug: false,
});
await litNodeClient.connect();
 
const resourceAbilities = [
  {
    resource: new LitActionResource("*"),
    ability: LitAbility.PKPSigning,
  },
];
 
/**
 * For provisioning keys and setting up authentication methods see documentation below
 * https://developer.litprotocol.com/v2/pkp/minting
 */
const authNeededCallback = async (params: AuthCallbackParams) => {
  const response = await litNodeClient.signSessionKey({
    sessionKey: params.sessionKeyPair,
    statement: params.statement,
    authMethods: [],
    pkpPublicKey: PKP_PUBLIC_KEY,
    expiration: params.expiration,
    resources: params.resources,
    chainId: 1,
  });
  return response.authSig;
};
 
const sessionSigs = await litNodeClient
  .getSessionSigs({
    chain: "ethereum",
    expiration: new Date(Date.now() + 1000 * 60 * 60 * 24 * 7).toISOString(),
    resourceAbilityRequests: resourceAbilities,
    authNeededCallback,
  })
  .catch((err) => {
    console.log("error while attempting to access session signatures: ", err);
    throw err;
  });
 
const pkpWallet = new PKPEthersWallet({
  pkpPubKey: PKP_PUBLIC_KEY,
  rpc: POLYGON_MUMBAI_RPC_URL,
  controllerSessionSigs: sessionSigs,
});

Use with ZeroDev

Use the provider from Lit Protocol to create a smart account signer, which can be passed to a validator. For detailed guidance on using a validator, refer to our documentation on creating accounts.

import { signerToEcdsaValidator } from "@zerodev/ecdsa-validator"
import { KERNEL_V3_1, getEntryPoint } from "@zerodev/sdk/constants"
import { createPublicClient } from "viem";
import { polygonAmoy } from 'viem/chains';
 
const smartAccountSigner = await providerToSmartAccountSigner(pkpWallet);
 
const publicClient = createPublicClient({
  // Use your own RPC provider (e.g. Infura/Alchemy).
  transport: http('https://rpc-amoy.polygon.technology'),
  chain: polygonAmoy,
})
 
// Pass your `pkpWallet` to the validator
const ecdsaValidator = await signerToEcdsaValidator(publicClient, {
  signer: pkpWallet,
  entryPoint: getEntryPoint("0.7"),
  kernelVersion: KERNEL_V3_1
})
 
// You can now use this ECDSA Validator to create a Kernel account