A StarkWare researcher has developed a method allowing quantum-safe Bitcoin transactions on the live network without protocol changes. The scheme, called Quantum Safe Bitcoin (QSB), utilizes hash-based proofs instead of traditional digital signatures like ECDSA, which are vulnerable to future quantum computers.
This approach operates within current Bitcoin consensus rules, bypassing the need for soft forks or lengthy governance processes like BIP-360. However, QSB incurs substantial costs, estimated between $75 and $200 per transaction due to intensive off-chain computation required. This makes it an emergency fallback rather than a permanent solution, contrasting with protocol-level upgrades that remain the more scalable long-term fix.