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# System prepended metadata

title: Ethereum Protocol Fellowship - The Third Cohort (Update 10)

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# Ethereum Protocol Fellowship - The Third Cohort (Update 10)

This is the tenth update for Ethereum Protocol Fellowship - The Third Cohort.

In the past two weeks, I finished implementing sanity checks of user operations when the bundler received them and prepared the environment for running bundler spec tests.

- Description: https://github.com/eth-protocol-fellows/cohort-three/blob/master/projects/4337-bundler-rust.md
- Architecture and specification:  https://hackmd.io/@Vid201/aa-bundler-rust
- GitHub repository: https://github.com/Vid201/aa-bundler/

## Updates

1. Sanity checks of user operations merged: https://github.com/Vid201/aa-bundler/pull/24
2. Prepare docker files for running bundler spec tests: https://github.com/Vid201/aa-bundler/pull/52
3. Chain id is retrieved from the execution client: https://github.com/Vid201/aa-bundler/pull/56 
4. RPC endpoint eth_getChainId: https://github.com/Vid201/aa-bundler/pull/56
5. RPC endpoints eth_supportedEntryPoints and eth_estimateUserOperationGas: https://github.com/Vid201/aa-bundler/pull/59
6. Fix bug when calling function simulateValidation on entry point smart contract: https://github.com/Vid201/aa-bundler/pull/61

This was the week I first started checking and running the bundler spec tests. As expected, only the tests for some RPC endpoints passed, and others failed. The goal for the coming weeks is to pass tests now that the environment is set up gradually.

![Bundler spec tests](https://i.imgur.com/sUv1Jot.png)


## Next steps

There is only one week left in the fellowship; how time flies! My goal is to fix some of the current minor bugs in the repo (CI caching, estimate user operation gas ...) and then work on opcode banning and simulation of user operations to pass some more tests until ETH Denver. I will also work on the presentation and final document for the fellowship.

Since I will not finish the bundler in one week, I will continue working on it open-source after the fellowship.