No soft fork required: StarkWare verifies quantum-safe locking scheme on Bitcoin mainnet, but it is not yet suitable for large-scale use

Odaily reports that Starknet has published an introduction to its Quantum-Safe Bitcoin (QSB) scheme, stating that StarkWare researchers have verified a quantum-safe locking mechanism on the Bitcoin mainnet that requires no soft fork, no new opcodes, and no changes to consensus rules. The first QSB output was spent on August 26, 2026, in Bitcoin mainnet block 964,199, with the associated GPU computation cost reduced from approximately $320 to about $50. QSB builds its locking mechanism through hash computation, but each transaction still requires substantial computation, and moving assets into the scheme still requires a traditional transaction that carries quantum risk. The transaction does not comply with Bitcoin Core's default relay rules, and there is currently no accompanying wallet, address format, or recovery process. StarkWare stated that QSB is an emergency research solution, and that the long-term solution still requires the introduction of post-quantum signature mechanisms via a soft fork. Starknet's full quantum resistance also depends on the progress of Ethereum's underlying upgrades.