Bitcoin Needs Only 2 Steps To Become Quantum-Resistant, Core Dev Says

Bitcoin open-source engineer Matt Corallo pushed back on claims that Bitcoin developers are “sleepwalking” on quantum risk, arguing instead that a practical post-quantum roadmap is already taking shape and may be simpler than critics suggest. Speaking on the Unchained podcast episode published Feb. 22, Corallo said the key work can be framed in two main steps: enable post-quantum key commitments first, then decide later when to disable vulnerable legacy spend paths.

Corallo’s appearance was a direct response to criticism popularized by Castle Island Ventures’ Nick Carter, who has argued Bitcoin developers are not treating the quantum threat with sufficient urgency. Corallo said that characterization misses both the amount of ongoing work and an important technical point about how many Bitcoin wallets already function.

He argued that most wallets using seed phrases already have a quantum-safe anchor at the wallet-derivation layer, even if the on-chain public key and signature scheme remain vulnerable to a future cryptographically relevant quantum computer. In his telling, that meaningfully changes the migration problem and could reduce how much disruption is required if the threat becomes urgent.

Corallo’s 2-Step Roadmap For Bitcoin

Corallo repeatedly returned to what he called the core sequence for Bitcoin’s quantum preparation. “There are only two steps,” he said. “The first relevant step is just adding the ability to commit to a postquantum public key. I think that should be done soon.”

He added that this first phase is increasingly converging around hash-based signatures, with current discussion focused less on whether to do it and more on exact implementation details. Corallo said he sees “pretty strong consensus” around hash-based approaches and pointed to work tied to BIP 360, while also noting debate continues on the precise format.

The second step, in his framing, is the politically harder one: deciding when legacy, quantum-vulnerable spend paths should no longer be accepted. That is the point where old coins that have not migrated — including lost or abandoned coins — become part of a market-driven fork decision, in his view.

Corallo’s argument for moving early on the first step but delaying the enforcement switch rests on cost and wallet behavior. He said wallets can start committing to post-quantum public keys now without immediately paying the size and fee overhead of using large post-quantum signatures on-chain.

“You really want an upgrade path that is free for now,” Corallo said. “The wallets know how to spend it. They know how to build these keys, how to sign with these keys. They just don’t have to use it yet.”

He argued this avoids a scenario where wallets postpone upgrades because post-quantum transactions are larger and more expensive, while still preparing the system for a future enforcement moment.

“Only two steps” required to make Bitcoin quantum-resistant?

In this @Unchained_pod episode, @TheBlueMatt joins me to discuss:

Why he thinks Nic Carter is wrong about the quantum threat to Bitcoin
Why he disagrees with Nic on his ranking of Bitcoin’s most influential… pic.twitter.com/2r2g42myJD

— Laura Shin (@laurashin) February 22, 2026

The ‘Nobody Is Working On It’ Narrative

Corallo also disputed the idea that Bitcoin development circles are ignoring the issue. He pointed to research and engineering work at organizations including Blockstream Research and Chaincode Labs, cited Ethan Heilman and co-authors working on BIP 360, and said post-quantum discussion on the Bitcoin developer mailing list has grown steadily.

At one point, he said mailing-list discussion has risen to “30 or 40%” of posts, describing that as evidence of sustained attention rather than neglect.

Corallo did not argue the problem is trivial. He acknowledged migration of active wallets could take years and said critics are right that the social and market consequences of disabling insecure spend paths would be contentious. But his central claim was narrower: Bitcoin does not need a fully finalized end-state today to begin meaningful preparation now.

At press time, BTC traded at $65,953.