A Developer’s Guide to Building Next-Gen Smart Wallets With ERC-4337 — Part 2: Bundlers
In Part 1, a smart account was deployed and the first UserOperation successfully executed through the EntryPoint. At that point, everything worked — but a critical part of the system stayed mostly invisible: the bundler. Bundlers are the bridge between account abstraction and the Ethereum execution layer. They take UserOperations from a separate mempool, pay gas costs upfront, and get reimbursed through the protocol. Understanding how they work—the validation rules, reputation system, and economic incentives—is essential for debugging […]