Bitcoin Mines First Quantum-Safe Transaction with StarkWare's QSB Method

StarkWare researcher Avihu Levy developed Quantum Safe Bitcoin (QSB), a method to protect against quantum computer attacks. The first QSB transaction was mined on August 26, 2026, in block 964,199 by MARA through its private Slipstream service.

The test used hash-based protection without changing Bitcoin's consensus rules. Levy estimated that the approach provides about 118 bits of security under Shor's algorithm and roughly half that level under Grover's algorithm.

The QSB method wraps each transaction in a proof-of-work puzzle secured by hash functions, reducing reliance on exposed signatures during transaction broadcast. However, the transaction format remains non-standard, and ordinary Bitcoin software does not relay it.