Vitalik proposes the "Minimalist Consensus Chain" plan: Reconstructing Ethereum's consensus layer using ZK-STARK, with the goal of supporting one million validators.

Ethereum co-founder Vitalik Buterin has released a new research paper titled "The Extremely Lean Chain," proposing a drastically streamlined design for Ethereum’s consensus layer. The plan leverages "Lean" upgrades including single-slot finality, recursive STARK proofs, and quantum-resistant signature aggregation to significantly reduce consensus chain state storage requirements, shifting most state management and zero-knowledge (ZK) proof responsibilities to validators. Vitalik argues that this proposal would eliminate the Beacon Chain’s current complex periodic state processing workflows, drastically cut system overhead, enable Ethereum to scale to millions of validators in the future, and also improve validator anonymity. Per the design, validators no longer need to store large amounts of data such as public keys, withdrawal credentials, activation and exit records on-chain long-term; instead, they only retain minimal core state like effective balances and public key indexes, while the rest of the data is submitted and verified periodically via STARK proofs. The proposal also introduces mechanisms like daily balance update proofs, ZK-STARK privacy protection, and daily re-randomization of validator identities, which enhance network scalability while further boosting privacy and censorship resistance. Vitalik noted that with an approximately one-day proof period, the scheme can complete proof generation on regular hardware, reduce on-chain burden through proof aggregation, and provide a new technical roadmap for the long-term expansion of Ethereum’s consensus layer.