Quantum-Secure Bitcoin Transaction Mined on Mainnet Without Protocol Changes

A quantum-safe Bitcoin transaction has been successfully mined on mainnet without changing the network's consensus rules. The transaction, facilitated by Quantum-Safe Bitcoin (QSB), was developed by StarkWare engineers Avihu Levy and Tomer Giladi in collaboration with the MARA Foundation.

The use of QSB enables quantum-resistant signatures under existing Bitcoin rules, adding a hash-based lock to protect against potential quantum-computing attacks. However, researchers note that high GPU costs and nonstandard transaction formats currently limit near-term adoption of QSB.

This achievement marks the transition of QSB from a research proposal in April 2026 to a live Bitcoin transaction on mainnet. The development highlights the importance of protocol-level updates for long-term crypto security and adoption, suggesting that QSB's benefits may be outweighed by its current limitations.