## EPF Week 20 Update

This week, I focused on upstreaming some PR's to lighthouse. It's pretty awesome that the project has progressed to a point to where they're ready to accept my validator client related PR's. Additionally this week, I updated my project proposal and started on the final report for EPF. It was a slightly lighter week since I was a bit pre-occupied meeting with vendors and wedding venue in Italy, but I'm happy I still got these PR's in.

## PR's
1. [Gloas vc ptc duty](https://github.com/sigp/lighthouse/pull/8338)

TLDR:
duties_service will now spawn a background polling task for the current and next epoch to check whether any of the registered validators are in a ptc committee. Since re-org is possible, we also poll every slot. The beacon node querying is performed by new request endpoint POST validator/duties/ptc/{epoch} per beacon api spec.

To save on bandwidth similar to attestation committee polling, the ptc polling will make a tiny initial requests to learn the dependent_root, compare with the cached dependent_root, and only fetch full duties for the epoch if the root has changed (or if the root is unknown like for a new epoch). Old duties are pruned based on HISTORICAL_DUTIES_EPOCHS.

2. [gloas VC block production](https://github.com/sigp/lighthouse/pull/8313)

TLDR:
In Gloas, the publish_block flow in the VC is modified to add the get, sign, and publish of a payload envelope, which occus when the BeaconBlock.body.signed_execution_payload_bid.message.builder_index is the same as the proposer's validator index.

Additionally, when requesting a block from the BN, we will no longer receive blobs or kzg commitments. Instead, payload envelopes and blobs will be released by the proposer in the self-building scenario or otherwise by the in-protocol builder. There is no longer a concept of requesting unblinded or blinded blocks since all CL blocks just contain bids.

Client-side endpoints were added to support requesting gloas block and additionally envelopes. All the new and modified epbs beacon api endpoints are defined in PR.