Ethereum Researchers Propose SPHINCS- Post-Quantum Signature Scheme Verifying at 127,000 Gas

According to Ethereum Research, on June 12, researchers published SPHINCS-, a stateless post-quantum signature verification scheme designed for EVM compatibility without requiring protocol changes. The proposal, authored by nicocsgy with contributions from Vitalik Buterin, replaces standard SHAKE256 hash functions with KECCAK256, enabling Solidity implementation of quantum-resistant wallet verification.

The C13 variant verifies quantum-resistant signatures at approximately 127,000 gas with a 3,704-byte signature size, compared to standard SLH-DSA-SHA2-128-24, which costs 142,000 gas with 3,856-byte signatures. The scheme targets signing budgets between 2^14 and 2^20 per key, reflecting typical wallet usage patterns rather than general-purpose cryptographic standards.