EPF Dev Update #15

Project links

• Project: EIP-4844 Consensus Client
• Design: Builder API for Blobs

Summary for week 16 (2023/2/13-2023/2/20)

• Lighthouse backfill sycn rate-limiting (lighthouse#3936): continued to work on review feedback and added some unit tests. Looked into the impact of changing the number of backfill batches processed (per slot) vs the CPU usage. I've published some analysis results here. Big shout out to @divagant-martian for the help reviewing and unselfishly sharing her knowledge and experience - I've learned a lot in just a single PR!
• EIP-4844: Free the blobs PR by @arnetheduck: I read through the changes in this PR, as the block / blob decoupling is quite a substantial change and will have an impact on most of my outstanding PRs on beacon-APIs, builder-specs, ethereum-consensus, lighthouse and mev-rs.
  • Required changes in Lighthouse has been listed in this issue created by @realbigsean
• Worked on the blob signing endpoints and particpated in the spec discssions
  • I drafted a diagram to reflect the changes required by the latest block/blob decoupling design, more specically, the need to sign blobs individually.
  • Implemented an initial draft of blob signing endpoints and validator client blob signing functionality in Lighthouse. PR created here. Thanks to @realbigseans's for helping!
  • @tbenr from Teku raised a great point against using blinded blob flows by default - looks like we might have to go with signing full blobs by default. Looking for some more inputs on this proposal before I continue on the above PR.
• Other updates:
  • Add Deneb (EIP-4844) types and presets ralexstokes/ethereum-consensus#170: I've updated types to reflect latest spec changes
  • Add support for EIP-4844 types in mev-rs#77: created a draft PR this week, will continue to update to latest spec changes
  • Add blob download endpoint (getBlobsSidecar) beacon-APIs#286: I'm working on updating this to latest specs - clients are looking to impelement this quite soon and this endpoint may be used by hive tests for verifying blobs.

I plan to continue to work on these tasks this week, but will be shifting my focus to my final EPF development update and project report as the Fellowship program is coming to an end. The last couple of months have been amazing, and I've thoroughly enjoyed learning about the protocol, working as an Ethereum core dev and learning the Rust language from scratch \o/. I will spend some time reflecting on this journey and hopefully I'll be able to continue to contribute to the Ethereum ecoysystem and be part of this amazing community. See you in the final dev update!

WIP Tasks

EIP-4844

• beacon-APIs: download blob (PR)
• builder-spec update to support 4844 (PR)
• mev-rs update to support 4844 (PR)
• lighthouse update 4844 builder flow (PR)
• lighthouse update download blob API to latest spec
• lighthouse blob signing endppionts issue (PR)
• lighthouse validator blob signing functionality (Same PR as above)

Other potential tasks

• Update beacon-api-client to support 4844 (may not have time to get to this)