Vitalik Buterin Proposes 'Extremely Lean' Ethereum to Shrink Validator State to 6 Bytes

According to a post on Ethereum Research this past weekend, Vitalik Buterin outlined a technical proposal to radically shrink Ethereum's consensus layer using zero-knowledge proofs, part of a broader "Lean Ethereum" initiative aimed at making the network more efficient and secure.

The "Extremely Lean Chain" proposal centers on redesigning the Beacon Chain through two phases. Phase 1 removes most validator data from the chain and replaces per-epoch balance updates with daily ZK-STARK proofs submitted by validators, reducing onchain state to roughly 6 bytes per validator. Phase 2 adds privacy by giving each validator a fresh anonymous key daily, creating a rotating, unlinkable validator set. Buterin noted these changes "may allow consensus to scale to millions of validators if needed." The Lean Ethereum initiative could take three to four years to develop, with Buterin describing it as the network's "third major iteration," comparable to the Merge in technical complexity.