Bitcoin's quantum defense just got its first working prototype. Olaoluwa @roasbeef Osuntokun, CTO of Lightning Labs, published a functional tool to the Bitcoin developer mailing list that solves one of the hardest problems in Bitcoin's long-term security, how to protect the network from quantum attacks without locking millions of users out of their own wallets. The problem is a painful paradox. Bitcoin's leading quantum defense proposal (BIP-360) would disable the current signature system network-wide if a quantum threat emerged. That protects the network, but every wallet that hasn't migrated to the new quantum-resistant format gets frozen permanently. The coins are still there. The rightful owner just can't access them. Osuntokun's prototype is the escape hatch. Instead of proving ownership with a digital signature, the system lets users mathematically prove they created the wallet using its original seed phrase, without ever revealing the seed itself. Recovering one wallet doesn't compromise any others derived from the same seed. It replaces "I can sign this transaction" with "I can prove this wallet came from me." It already runs on a consumer MacBook. Generating the proof takes about 55 seconds. Verification takes under two seconds. The proof file is roughly 1.7 MB. There's no formal proposal to integrate this into Bitcoin yet and no deployment timeline. But the prototype closes a gap that had only existed in theory until now, a credible path to quantum resilience without the collateral damage of stranding user funds.