I recently read a very detailed analysis by Vitalik about how Ethereum is preparing to counter the threat from quantum computers. And truly, this is a problem that not everyone pays attention to.

The main danger here is Shor's algorithm — a quantum algorithm capable of breaking the cryptographic systems we use today. According to Vitalik, four core components of Ethereum currently rely on elliptic curve cryptography or discrete logarithm problems, all of which could be attacked if sufficiently powerful quantum computers emerge. These components include BLS signatures at the consensus layer, KZG data availability commitments, ECDSA account signatures, and zero-knowledge proofs.

The most concerning part is that the window of opportunity could be very narrow. The Metaculus platform estimates a 20% chance that sufficiently powerful quantum computers will appear before 2030. Vitalik even warns that elliptic curve cryptography might fail before the 2028 U.S. presidential election. Therefore, the Ethereum Foundation established the Post-Quantum Security team in January 2026, led by Thomas Coratger, with $2 million allocated for research.

But the interesting part is how they are building the solution. The ETH2030 project has already deployed a full post-quantum cryptography system, including six signature algorithms resistant to Shor's algorithm and similar threats. Developers have tested the system on 48 packages with over 20,900 successful tests. This system also adds 13 custom EVM precompiles to accelerate network-based encryption and verify STARK proofs.

Of course, there is a cost issue. Quantum-secure signatures are much more expensive than current ECDSA — potentially up to 200,000 gas instead of 3,000 gas. To address this, they are using recursive STARK aggregation, compressing multiple signatures into a single proof.

At the consensus layer, ETH2030 introduces a dual signature verification that combines post-quantum cryptography with traditional cryptography, allowing validators to gradually transition without disruption. KZG commitments are replaced with Merkle- and graph-based schemes, avoiding dependence on elliptic curves.

On February 27, 2026, developers successfully ran the system on the Kurtosis devnet, creating blocks and verifying all new precompiles. This demonstrates that Ethereum is making a significant step forward in protecting itself against a threat that most people have not fully recognized the importance of.