Introduction to Bundlers

An introduction to the Etherspot implementation of an ERC-4337 bundler.

What is an ERC-4337 bundler?

In short, a bundler will work with a number of userOperations to ensure they are included on chain.
It is a node (block builder) that bundles multiple UserOperations and creates an EntryPoint.handleOps() transaction. Note that not all block-builders on the network are required to be bundlers.
We're building a modular typescript implementation of this called Skandha.