First Quantum-Resistant Bitcoin Transaction Confirmed on Mainnet Without Protocol Change

The workaround comes with an important limitation: only private mempools such as MARA's Slipstream can currently accept it.

Bitcoin got its first known quantum-resistant transaction on mainnet today, mined through MARA’s private Slipstream mempool using a method called Quantum Safe Bitcoin, built by StarkWare’s Avihu Levy.

It closes a real gap in how Bitcoin protects funds in transit, without asking the network to change a single consensus rule, though even the people behind it call it a stopgap rather than a fix.

How Quantum-Safe Bitcoin Closes the Mempool Gap

Bitcoin held behind a hashed address, the P2PKH format most wallets use, is already considered safe from quantum attacks. The problem shows up the moment someone spends it.

Sending Bitcoin means revealing the wallet’s public key, and that key sits exposed in the mempool for roughly the ten minutes it takes to confirm, exactly the window a quantum computer could exploit.

Levy built Quantum Safe Bitcoin to close that window without touching consensus rules. The scheme modifies Binohash, a technique from BitVM creator Robin Linus, wrapping each transaction in a proof-of-work puzzle whose security rests on hash functions believed to resist quantum attacks rather than on the signature itself.