Ethereum unveils post-quantum deposit contract proposal

Ethereum proposes a post-quantum-ready validator deposit contract with flexible key support and a permanent BLS retirement mode to boost security.

Ethereum developers have unveiled a draft proposal for a post-quantum-ready validator deposit contract, aiming to strengthen the network against future quantum computing threats. The proposal recommends replacing the current BLS (Boneh–Lynn–Shacham) signature scheme with a more flexible contract that supports variable-length public keys, credential metadata, and explicit scheme identifiers. Scheme 0 will represent existing BLS deposits, while future identifiers will enable the use of quantum-resistant cryptographic systems. A key feature of the contract is an irreversible mode that can permanently disable BLS deposits at a predetermined time, supporting a staged migration to new cryptographic standards. Deposit information would be relayed to the consensus layer via execution requests, moving away from the legacy Merkle-tree structure. The draft does not mandate a specific post-quantum algorithm, leaving that decision to future consensus. This initiative demonstrates Ethereum's proactive approach to security and aligns with industry efforts, such as NIST's planned deprecation of ECDSA by 2030.