A new proposal from Avihu Levy suggests that Bitcoin could be made quantum-safe immediately — without a protocol upgrade. The method, called Quantum Safe Bitcoin (QSB), works within Bitcoin’s existing rules and is designed to stay secure even against quantum computers running Shor's algorithm.

Instead of relying on vulnerable elliptic curve cryptography, the scheme uses a brute-force hash puzzle that produces a valid-looking signature. This avoids quantum attacks but comes at a cost: each transaction would require heavy GPU computation, estimated between $75 and $150. Because of that, researchers say it’s only practical for large-value transfers, not everyday payments.

Some experts, including Daniel Batten, argue the proposal doesn’t fully solve the quantum risk, especially for old exposed wallets holding around 1.7 million BTC. Researchers agree this is only a temporary “last-resort” solution, while long-term fixes — such as protocol upgrades and quantum-resistant signatures — remain the preferred path.