Using the @account-kit/infra Library for UserOperation Management

The @account-kit/infra library enables direct interaction with Alchemy's ERC-4337 bundler for advanced UserOperation management. The alchemyFeeEstimator function leverages underlying APIs, including rundler_maxPriorityFeePerGas and eth_estimateUserOperation, to estimate gas fees for UserOperations. Below are examples demonstrating how to estimate and send a UserOperation and how to retrieve a UserOperation by its hash using low-level Bundler APIs.

import { alchemy, sepolia } from "@account-kit/infra";
 
const YOUR_API_KEY = "<YOUR_API_KEY>";
export const YOUR_PRIVATE_KEY = "<YOUR_PRIVATE_KEY>";
export const chain = sepolia;
 
export const transport = alchemy({
  apiKey: YOUR_API_KEY,
});