Blockchain technology company Starkware said a transaction using researcher Avihu Levy’s anti-quantum Bitcoin (QSB) scheme was mined on the Bitcoin mainnet on August 26 without a soft fork, hard fork, or changes to consensus rules. According to Odaily, the transaction used 10,000 satoshis, was processed through MARA Foundation’s Slipstream service, and took several hours of GPU computation at a cost of about $150 to $200. Starkware said QSB uses hash-function-based anti-quantum spending conditions and reduces quantum attack risk through signature trial mining, but users still need to move funds manually and it cannot protect assets whose public keys have already been exposed. Starkware CEO Eli Ben-Sasson still supports introducing a protocol-level solution through a soft fork.