Aztec Targets Full Post-Quantum Migration by End of 2030

Aztec, an Ethereum Layer 2 for private smart contracts, published a roadmap on Oct. 15 targeting a full migration to post-quantum cryptography by the end of 2030. Hardened developer libraries to better protect private data are planned for early 2027.

The plan separates protecting confidential data today from replacing the cryptography that secures the network. In a “harvest now, decrypt later” attack, an adversary collects encrypted information and stores it until a sufficiently powerful quantum computer can decrypt it. As NIST explains, that risk can persist even if systems upgrade before such computers arrive.

Aztec says its existing design already gives developers ways to resist that attack, including hashing public keys to limit their exposure and supporting offchain delivery of private notes—the records recipients need to discover and use private funds. Applications choose how to encrypt and deliver those notes. The planned libraries aim to make safer patterns easier for developers to implement.

Replacing the Proof System

Protecting historical data is only part of the migration. Aztec’s current CHONK proving system relies on elliptic curves and pairings, according to its technical documentation. The roadmap says a sufficiently capable quantum adversary could forge proofs, which demonstrate that private transactions follow the network’s rules.

Aztec’s Alpha V5 went live on mainnet in July. Its proving-system design calls for users to generate proofs on phones or in browsers, while combining proofs for multiple contract calls without excessive memory requirements. The replacement must preserve those capabilities.

Aztec separately disclosed a critical V5 proving-system flaw in August that it said could let invalid transactions pass verification, putting funds and contract state at risk. Contributors could not determine whether it had been exploited. The October roadmap says fixes for critical vulnerabilities are included in the upcoming V6 release.

Aztec plans to select replacement signature, encryption and proving schemes during 2027, before integrating them across the network. The encryption decision requires benchmarks inside proof systems; the proving-system decision requires working recursion—the ability to verify one proof inside another—and zero knowledge, which keeps the underlying information private.

After selecting the schemes, Aztec says it must update addresses, key derivation, account and validator authentication, and provide a migration path for existing private state.

The final transition also depends on Ethereum. Aztec’s proof verification and blob commitments—the cryptographic commitments used for data availability on Ethereum—sit within Ethereum’s infrastructure. The roadmap says full post-quantum migration must account for upgrades to that infrastructure as well as Aztec’s own changes.