StarkWare conducts first quantum‑resistant Bitcoin transaction on mainnet

StarkWare researcher Avihu Levy successfully broadcast a quantum‑resistant Bitcoin transaction on the Bitcoin mainnet, marking the first on‑chain demonstration of the company’s Quantum Safe Bitcoin (QSB) scheme.

On‑chain confirmation

The transaction was confirmed in Bitcoin block 964,199. It spent a 10,000‑satoshi output protected by QSB, and the block was mined by MARA Pool after receiving the transaction through its Slipstream service.

How QSB works

QSB combines hash‑based one‑time signatures with computational searches that bind an authorization to a specific transaction. The design aims to prevent forgery even if a quantum computer were able to break Bitcoin’s elliptic‑curve cryptography.

Cost and processing requirements

StarkWare estimated the transaction cost between $150 and $200, reflecting several hours of GPU computation. Earlier estimates for generating a QSB transaction ranged from $75 to $150.

Network compatibility

QSB transactions are classified as non‑standard under Bitcoin Core’s default relay policies, meaning ordinary nodes do not propagate them. Direct submission through MARA’s Slipstream service was required for the transaction to reach miners.

Future outlook

StarkWare CEO Eli Ben‑Sasson described QSB as a safety net while protocol‑level solutions are developed. Bitcoin developers are also evaluating proposals such as BIP‑360, which would introduce a Pay‑to‑Merkle‑Root output type to address quantum‑related risks.