Bitcoin Developer Says Classical Code-Breaking Is the Nearer Threat, Not Quantum Computers

CoinJoin Chris, co-hosting the show, used his segment to push back on the idea that quantum computing is the clearest danger sitting in front of Bitcoin right now. His case: a classical break of the elliptic curve cryptography Bitcoin relies on is more likely to happen first, and the network is already better prepared for quantum than most people assume.

WHY QUANTUM IS STILL FAR AWAY

Bitcoin's signatures rest on the secp256k1 elliptic curve, the same math Chris referenced on air. No cryptographically relevant quantum computer exists today, and the gap to build one remains large. Breaking that curve is estimated to require somewhere between 1,200 and 2,330 stable logical qubits, while 2026's best machines manage only a few dozen logical qubits built on roughly 1,000 to 1,200 noisy physical ones. A March 2026 paper from Google Quantum AI, co-authored with Stanford's Dan Boneh, the cryptographer Chris pointed to by name as one of the field's best, cut the physical-qubit estimate needed for an idealized attack to under 500,000 and a runtime of minutes rather than days. That paper moved the conversation, but it did not close the gap: published hardware roadmaps for machines that could actually do this still stretch toward the end of the decade.

Chris argued the more immediate risk sits elsewhere. "My take on quantum is it is much more likely to have a classical break in elliptic curve cryptography long before quantum poses a threat," he said, adding that Bitcoin's post-quantum signature research is further along, and proportionally better resourced, than the threat currently warrants.

THE COVENANT WAITING IN THE WINGS

The segment's real pitch was for BIP 448, a bundle of three proposed Bitcoin script upgrades: OP_TEMPLATEHASH (BIP 446), OP_CHECKSIGFROMSTACK (BIP 348) and OP_INTERNALKEY (BIP 349). The bundle entered Draft status in March 2026 and began testing on the Bitcoin Inquisition signet in July 2026. No activation client exists yet and no mainnet signaling has begun.

What the bundle would enable is a covenant, a way to restrict what a transaction spending a coin is allowed to look like. Chris described the practical upside as reactive security: a vault that caps how much Bitcoin can leave per day, restricts withdrawals to a pre-approved address, or lets an owner claw back a transaction before it settles. That matters because today's hardware wallets only offer proactive security, locking a seed phrase away and hoping it's never exposed. Chris connected that gap directly to two incidents that have hit self-custody hardware this year: the Coldcard exploit that drained more than $116 million, and the October 2026 discovery that Ledger devices sold through a Southeast Asian reseller carried a hidden implant that read recovery phrases off the screen and transmitted them over a cellular network, a breach now linked to more than $90 million in losses.

THE LESSON FROM TAPROOT, AND FROM BIP-110

Chris was explicit about not wanting to rush this one. Taproot took three years to go from proposal to activation after developers oversold the timeline. BIP-110 went the other direction in August 2026: it activated with just 2.53 percent miner support, split off a minority chain that mined two blocks before stalling, and was marked closed within days, the most decisive rejection of a soft fork since SegWit2x. Chris's read is that BIP 448 should build the tooling and prove the use case first, gather broad support across miners, exchanges and node runners, and only then move toward activation. "Now that we have forked off the BIP 110 people, I think it's time to get serious about improving Bitcoin, because we're running out of time," he said, pointing to Europe's incoming cash-transaction limits as one reason the clock on reactive security and privacy improvements matters now, not eventually.

This story comes from the Simply Bitcoin Live show. Watch the full episode.