Ethereum Bets Big on Quantum Defense as Crypto's Survival Game Begins

What if every cryptocurrency you own could be hacked in 10 years? That's the scenario driving Ethereum's latest strategic shift—and it's not waiting to find out.

Earlier this January, the Ethereum Foundation formally elevated post-quantum security to a strategic priority, creating a dedicated Post-Quantum (PQ) team to drive research, tooling, and real-world upgrades. The move signals a fundamental shift: quantum computing has moved from distant theory to immediate engineering concern.

"Quantum computing is moving from theory into engineering," said Thomas Coratger, who leads the Ethereum Foundation's PQ team. "That changes the timeline, and it means we need to prepare."

The urgency isn't theoretical anymore. While Bitcoin's community has been debating quantum threats for over a year, Ethereum's 2026 mobilization represents the first major institutional response from a leading blockchain platform.

Industry-Wide Defense Mode

Ethereum isn't moving alone. Coinbase announced an independent quantum advisory board staffed with leading cryptographers to guide long-term blockchain security planning. Meanwhile, Optimism, one of Ethereum's largest layer-2 networks, laid out a formal 10-year roadmap to transition its entire Superchain stack toward post-quantum cryptography.

These coordinated moves mark a noticeable shift across the ecosystem. Post-quantum security is no longer a fringe topic for the far future—it's a live concern shaping development roadmaps and governance discussions across major platforms.

Coratger has spent the past year quietly working on post-quantum research within the foundation before this month's formal announcement. The creation of a dedicated team made public what had already become a growing internal concern: if quantum computers arrive sooner than expected, Ethereum needs to be ready well before that moment.

The Technical Challenge: Scaling Quantum-Safe Signatures

The team's focus centers on Ethereum's "consensus layer"—the system enabling thousands of validators to agree on which transactions are valid and which blocks get added to the chain. Today's system relies on cryptography that works efficiently now but could eventually crumble under quantum attack.

The biggest challenge involves replacing Ethereum's current signature system, which efficiently bundles thousands of validator approvals into manageable packets. "That system works incredibly well today," Coratger explained. "But the post-quantum alternatives don't have the same properties. Figuring out how to make them work at Ethereum's scale is a major challenge."

To address this, the foundation is building leanVM—a highly specialized piece of software designed to combine many post-quantum approvals into a single proof that can be added to the blockchain without overwhelming it. The technology is complex under the hood, but the goal is simple: keep Ethereum running smoothly even if the cryptography underneath needs to change.

"We already have test networks running with post-quantum signatures," Coratger confirmed.

Racing Against Time

Coratger stressed that Ethereum isn't in immediate danger. But the gap between how fast technology can change and how slowly decentralized networks can move explains why the foundation is acting now. The aim is completing the transition well before quantum computers become a real threat.

"The worst-case scenario is that quantum computers arrive and we're not ready," Coratger said.

What's struck him over the past year is how quickly the underlying science is advancing. "New breakthroughs are happening all the time. Sometimes it's hard to keep up."

The Ethereum Foundation is working closely with outside researchers and developers on post-quantum efforts, recognizing this isn't just a technical upgrade—it's a long-term engineering project that will shape how the network evolves over time.