FOCIL is a proposed Ethereum upgrade designed to preserve Ethereum’s censorship resistance by ensuring timely transaction inclusion

Quotes that support claims

He also acknowledged that these ideas are still preliminary. Key figures and assumptions are yet to be finalized, and certain components—such as FOCIL, a proposed mechanism for fast block inclusion—remain under debate. While some in the Ethereum community support it strongly, others have yet to engage with the concept. If FOCIL is ultimately not implemented, that decision could influence the network’s design strategy, particularly around optimal block construction.

FOCIL implements a robust mechanism to preserve Ethereum’s censorship resistance properties by guaranteeing timely transaction inclusion. FOCIL (Fork-choice enforced Inclusion Lists) is built in a few simple steps: In each slot, a set of validators is selected as inclusion list (IL) committee members. Each member builds and gossips one IL according to their subjective view of the mempool. The proposer and all attesters of the next slot monitor, store and forward available ILs. The proposer (or the builder if the block is not built locally by the proposer) includes transactions from all collected ILs in its block. The proposer then broadcasts the block including IL transactions to the rest of the network. Attesters only vote for the proposer’s block if it includes transactions from all stored ILs.