StarkWare researcher completes first quantum-safe Bitcoin transaction on mainnet
Tech & Launches ·
Avihu Levy's hash-based scheme protects Bitcoin transfers from future quantum attacks without altering Bitcoin's consensus rules.
A researcher at StarkWare, Avihu Levy, has completed the first confirmed transaction on the Bitcoin mainnet using a scheme called Quantum-Safe Bitcoin, or QSB, according to wublockchain.xyz. The transaction was designed to resist attacks from Shor's algorithm, a quantum computing method that could theoretically break the elliptic-curve cryptography Bitcoin currently relies on to secure private keys and signatures.
Rather than requiring a soft fork or any change to Bitcoin's consensus rules, QSB reroutes transaction security toward hash-based cryptographic assumptions, which are considered more resistant to quantum decryption than elliptic-curve methods. This approach allows the added protection to run on top of Bitcoin's existing protocol rather than needing network-wide upgrades or miner coordination to implement.
The scheme is still experimental and carries a notable cost: each transaction requires roughly $75–$150 in off-chain GPU computation, according to wublockchain.xyz. That expense reflects the computational overhead of generating hash-based proofs outside the chain before a transaction is broadcast, a tradeoff for avoiding changes to Bitcoin's base layer.
The demonstration has drawn attention beyond the initial report, with coverage from theblock.co framing the transaction as evidence that protocol-level upgrades may eventually be needed to address quantum computing threats to Bitcoin more broadly. That framing suggests QSB is being read less as a finished solution and more as a proof of concept pointing toward larger architectural questions.
What remains unclear is whether the $75–$150 per-transaction cost can be reduced enough for practical or widespread use, and whether hash-based schemes like QSB could be adopted more broadly without eventually requiring the very consensus-level changes the current demonstration avoided. It is also not yet known how quickly such off-chain approaches might be integrated into wallets or infrastructure, or whether Bitcoin's core developers will treat this as a template for future quantum-resistance work.