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# System prepended metadata

title: 'Dev Update Week 19 n 20: Prysm Optional Proofs'

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# Dev Update Week 19 n 20: Prysm Optional Proofs

**Developer:** Developeruche


### Summary

Following the successful presentation of the RISC-V execution sandbox research, the focus for these two weeks shifted to a new, major task: implementing "Optional Execution Proofs" within the Prysm consensus client. This work is a crucial first step toward integrating zkEVMs directly into Ethereum L1, allowing the consensus layer (CL) to verify execution payloads without a full execution layer (EL) client.

This effort involves a "rough prototype" PR to map out the significant architectural changes needed. The implementation follows a similar approach taken by Kev in the Lighthouse client, focusing on creating parallel logic that does not interfere with existing CL operations.

### Accomplishments These Weeks

* **RISC-V Presentation:** Successfully delivered the final research presentation on the "Changing the Execution sandbox from EVM to RISCV ISA" proposal, concluding the previous workstream.
* **Prysm Optional Proofs (WIP):** Began implementation of optional execution proof verification in the Prysm consensus client.
    * This is a **work-in-progress prototype** intended to discover all necessary architectural changes and is not intended for merging.
    * The core idea is to allow "Stateless Attestors" (nodes without an EL) to optimistically accept payloads and later verify them via a cryptographic proof received over a new subnet.
    * "Proof Generating Nodes" will be responsible for creating these proofs, which will be subsidized in the interim.
    * The prototype deliberately **avoids modifying fork choice logic**, instead using a "Proof Chain" structure to track proven blocks in parallel.
    * *Commits:* `add consensus types`, `add config`, `add proof cache`, `add proof gen n verify interfaces`, `add registry proof gen/verification`, `added cli flags`

### Links

[Pull Request #16003 (Prysm Optional Proofs)](https://github.com/OffchainLabs/prysm/pull/16003)
[Reference Notes (Lighthouse Implementation)](https://hackmd.io/@kevaundray/BJeZCo5Tgx)