Ethereum's leanVM Completes End-to-End Formal Verification; Full Post-Quantum Security Transition Targeted for December 2028

November 4: According to CryptoBriefing, Ethereum Foundation researcher Justin Drake announced on November 3 that leanVM has achieved end-to-end formal verification. leanVM is a minimal zkVM designed to efficiently aggregate hash-based post-quantum signatures, packing multiple signatures into a compact proof. In terms of performance, leanVM can handle more than 1,000 leanXMSS aggregations per second; leanXMSS is the hash-based signature scheme planned to replace BLS at the consensus layer.

At Devcon 8, Drake adjusted the target date for Ethereum's full transition to post-quantum security to December 2028, to leave room for the network forks required for the transition. The plan relies on three open-source projects: leanVM, leanXMSS and leanSpec. The Ethereum Foundation is developing open-source implementations and advancing formal verification, while encouraging innovation through incentives such as the Poseidon Prize. The report noted that the formal verification of leanVM proves that the code conforms to its specification, but December 2028 remains a target, not a commitment.