Vitalik proposed the "extremely simplified chain" solution, where validators submit STARK proofs daily, and the state storage is compressed to 6 bytes

Ethereum co-founder Vitalik Buterin published the proposal "The Extremely Lean Chain," demonstrating how to radically compress the state requirements of the Ethereum consensus chain in the context of the "Lean" upgrade. This plan shifts responsibility to validators, who manage and periodically prove their state through ZK proofs, thereby eliminating the processing burden for each epoch and potentially supporting millions of validators.

The core mechanisms include: removing the validator public keys from the on-chain state, storing only the deposit tree index; canceling real-time reward and penalty processing, with validators generating daily STARK proofs of their participation and updating balances; completely re-randomizing validator identities daily, achieving strong anonymity through ZK-STARK, with withdrawal addresses exposed only at the time of withdrawal and not publicly linked to deposits or on-chain activities. Vitalik stated that based on upgrades such as single-slot finality and quantum-resistant signature aggregation, the state requirement per validator could be compressed from approximately 180 bytes to 6 bytes. The daily proof cost for a single validator requires processing about 5400 Merkle branches, which can be completed within 1 hour on ordinary hardware, and the on-chain burden can be reduced through aggregated proofs. Additionally, this design can achieve a "virtually free" single secret leader election function, with 1 day as the conservative cycle length and 1 hour as the lower limit.