Starkware reports first “quantum-safe” Bitcoin transaction mined on mainnet Starkware — the firm best known for building the Ethereum layer‑2 Starknet — says it has successfully mined what it calls the first quantum‑safe Bitcoin transaction on the Bitcoin mainnet. The experiment tests a way for holders to protect coins from a future quantum computer attack without altering Bitcoin’s consensus rules. What happened - The transaction used “Quantum‑Safe Bitcoin” (QSB), a method developed by Starkware researcher Avihu Levy and published in April. Engineer Tomer Giladi turned the proposal into a working mainnet transaction, which Starkware said “holds up against an adversary running a working quantum computer.” - Rather than replacing Bitcoin’s elliptic‑curve cryptography, QSB adds a second, hash‑based lock to a transaction. That hash lock is resistant to the kind of private‑key recovery a large quantum computer could perform against elliptic curves. - To produce the transaction, Starkware used “signature grinding” — off‑chain computational work that finds a transaction hash Bitcoin will accept as a validly formatted signature. The current workflow also requires transactions to be submitted directly to miners. Why this matters - Bitcoin today relies on elliptic‑curve cryptography. In theory, a sufficiently powerful quantum computer running Shor’s algorithm could derive private keys from public keys and steal funds. Defending Bitcoin network‑wide would likely require a protocol change — either a soft fork (backwards‑compatible) or a disruptive hard fork. - QSB offers a stopgap for individual holders: a way to move coins into an output that a working quantum computer “cannot open,” according to Starkware. CEO Eli Ben‑Sasson said he still prefers a community‑wide soft fork as the long‑term fix, but sees this transaction as reassurance that holdings can be protected before such a change. Limitations and caveats - Starkware is explicit that QSB does not make Bitcoin fully quantum‑safe. It protects specific transactions using hash‑based security but cannot safeguard addresses whose public keys have already been exposed (for example, reused addresses). - The approach currently requires miners to be the direct recipients of the transaction, and it doesn’t replace the need for a protocol‑level upgrade to secure the whole network. - “This amazing feat should not be viewed as a message saying ‘Bitcoin is prepared for the quantum threat,’” Ben‑Sasson warned. He urged the community to take the soft‑fork route seriously: “Huston, we’ve got a problem,” he wrote. Context - Interest in Bitcoin’s quantum vulnerability has been rising. In June, Coinbase’s quantum advisory council estimated roughly 7 million BTC could be at risk because of exposed public keys and address reuse. Bottom line Starkware’s experiment demonstrates a practical, miner‑relayed technique to shield specific Bitcoin holdings from a hypothetical quantum attacker today, but it’s not a substitute for a coordinated protocol upgrade. The test adds urgency to ongoing discussions about how — and when — the Bitcoin ecosystem should adopt quantum‑resistant changes. Read more AI-generated news on: undefined/news