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Dev Update Week 8 (robzajac)

Last week I continued development of the light client APIs in teku. While I was sick for the first few days of the week, towards the end I completed:

  • Merged implementation of merkle multiproofs for SSZ objects in teku. This gives us the ability to generate an inclusion proof for a field in an SSZ object, which is especially useful for verifying current_sync_committee in a BeaconState for the light client bootstrap path, and later for light client updates.
  • Implemented and opened a PR for the GetLightClientBootstrap endpoint in teku. This is the first major endpoint of the light client APIs, which enables callers to sync to the beacon block header associated with the checkpoint root they provide.
    • Added some integration testing for the endpoint in the teku repo, and validated manually.
    • Received code review from the teku team, to continue iterating on the PR this week.
  • Read Vitalik's post on applications in the Ethereum ecosystem, which has interesting inspiration for Ethereum use cases.

This week I would like to:

  • Update the LightClientBootstrap PR and merge into teku, including any additional testing (followup PR with acceptance test and manual testing).
  • Work on the interface to GetLightClientUpdatesByRange, opening a PR for the SSZ objects and a stubbed endpoint.
  • Continue reading and following the latest in light client research and development, specifically etan's latest consensus-specs update to add ExecutionPayloadHeader to light client data.
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