StarkWare's Quantum-Safe Bitcoin Method Completes First Mainnet Transaction
A researcher at StarkWare has successfully executed the first mainnet transaction using the Quantum-Safe Bitcoin (QSB) method, a way to protect transactions from potential quantum attacks. The QSB scheme, developed by Avihu Levy, uses hash-based commitments and hash-to-signature puzzles instead of elliptic-curve cryptography. This approach is designed to be resistant to attacks using Shor's algorithm.
The transaction, which took place on August 26, demonstrates that QSB can operate under Bitcoin's existing consensus rules without requiring new opcodes or a soft fork. However, the method comes with significant computational costs, with each spend requiring approximately $75-$150 in off-chain cloud GPU computation before broadcast.
While this achievement provides reassurance that holdings can be protected, it does not make Bitcoin quantum-safe. QSB only protects legacy outputs and does not secure Taproot, Lightning channels, or previously exposed keys. A protocol-level Bitcoin upgrade remains under study, with developers considering alternative approaches to post-quantum signature systems.