Bitcoin Gets First Quantum-Safe Transaction via StarkWare’s QSB Method
A quantum-safe transaction has been successfully completed on Bitcoin's mainnet using StarkWare's QSB method. The achievement was made by StarkWare researcher Avihu Levy, who built the QSB method on his own time and published its research in April 2026.
The QSB method adds a hash-based lock to Bitcoin without requiring any soft fork or consensus change. It relies on signature grinding, which produces a valid Bitcoin signature without requiring a private key. This process currently costs between $75 to $150 in GPU computation.
The transaction was confirmed on August 26, 2026, and was facilitated by MARA Slipstream, which provided the mining path. StarkWare CEO Eli Ben-Sasson stated that Levy 'took this on after hours, as a passion project, and has now shown that Bitcoin has no expiration date.'
The QSB method closes the exposure gap in Bitcoin's existing signatures, which depend on elliptic curve cryptography that can be broken by a sufficiently powerful quantum computer. Shor's algorithm cannot break hash functions, making them more secure against quantum attacks.