New Wallet Provides Solution to Bitcoin's Quantum Vulnerability Without Requiring a Fork

The developers of a newly launched wallet claim to have discovered a method to mitigate the risks associated with quantum computing by leveraging a smart contract layer that operates in tandem with the Bitcoin network, without requiring any modifications to the network itself. On Tuesday, Postquant Labs introduced the Quip Network's post-quantum bitcoin wallet, which operates on the Arch Network, a platform enabling developers to build smart contracts directly anchored to Bitcoin, rather than relying on a separate chain or wrapped tokens. The Quip wallet utilizes this infrastructure to implement a post-quantum signature scheme known as WOTS+, or Winternitz One-Time Signature, in addition to Bitcoin's existing security measures. WOTS+ is a tested cryptographic technique that does not rely on elliptic curve mathematics, which can be compromised by a quantum computer. By utilizing a 'Layer 2' network, which is a separate network built on top of Bitcoin to process transactions and settle them back to the main chain, developers can add features without altering Bitcoin's base layer. According to Postquant Labs CEO Colton Dillion, 'The Bitcoin community has delayed addressing the quantum problem for years, despite it being discussed by Satoshi himself. Developers estimate that a protocol upgrade could take 5 to 10 years, but our approach provides similar protection immediately.' The launch of Quip occurs amidst an ongoing debate within the Bitcoin community regarding the best approach to addressing quantum risk. Recently, prominent developer Jameson Lopp, along with five others, proposed BIP-361, which would phase out quantum-vulnerable addresses over a fixed five-year timeline and freeze coins that fail to migrate, including the approximately 1.1 million bitcoin attributed to Satoshi Nakamoto. Meanwhile, Paul Sztorc's eCash hard fork proposal involves creating a copy of the Bitcoin chain and introducing seven sidechains, including a quantum-resistant one, partly funded by reassigning Satoshi-pattern coins on the new ledger to investors. Both proposals have faced pushback from the community. Quip's approach suggests that neither of these proposals is necessary, as their setup requires no soft fork, consensus change, or community vote. A soft fork is a Bitcoin upgrade that tightens existing rules, allowing older software to still function, but it requires broad miner and node support to activate. The last major soft fork, Taproot, occurred in 2021, and the next one, if it happens, could take years. The three approaches have different perspectives on the issue. Lopp argues that Layer 2 protection, like Quip's, is insufficient because Bitcoin mainnet public keys are still vulnerable to leakage when a user broadcasts a transaction, providing a potential target for a future quantum attack. However, there are some caveats to consider. The wallet app is scheduled to launch next week, and a third-party audit is currently underway but not yet complete. Quip's quantum-resistant accounts are already available on Ethereum and Solana, but the Bitcoin deployment is new, and Arch Network is still a relatively early-stage infrastructure. Postquant Labs CTO Dr. Richard Carback, who has collaborated with eCash inventor Dr. David Chaum, now an advisor to the project, stated that their approach reduces the window for a quantum attack to as little as two blocks, approximately 20 minutes. Sztorc argues that incremental patches, such as Quip's approach, are precisely why Bitcoin needs a clean fork with quantum resistance built-in from the start. The Layer 2 approach, which includes Quip and Blockstream's hash-based signature work on the Liquid Network, suggests that both other positions overreact to the threat, and better infrastructure can handle it without modifying Bitcoin itself. The success of each approach depends partly on the timeline for the development of quantum computers. Historically, the Bitcoin holders most concerned about quantum risk have also been the most resistant to wrapped or smart-contract-anchored products.