ERC-8262 Reference Implementation

Verifier router, interfaces, and one circuit for ERC-8262 (Zero-Knowledge Compliance Oracle). Licensed CC0-1.0, except contracts/interfaces/IUltraVerifier.sol, which mirrors the ABI of a Barretenberg-generated verifier and is Apache-2.0.

Layout

contracts/
  ERC8262Verifier.sol         router: per-proof-type verifier registry + version history
  interfaces/
    IERC8262Verifier.sol      verifier router interface
    IERC8262Oracle.sol        oracle interface
    IERC165.sol               ERC-165 interface
    IUltraVerifier.sol        per-circuit verifier ABI (Apache-2.0)
  libraries/
    ProofTypes.sol            proof-type IDs + public-input validation
    AccessControl.sol         GUARDIAN / REGISTRAR / CONFIG roles
    Ownable2Step.sol          two-step ownership transfer
    Pausable.sol              global + per-proof-type pause
circuits/
  compliance/                 COMPLIANCE (0x01) circuit (Noir)
  shared/                     shared Noir crate (hashing, Merkle, ECDSA, risk score)

The Barretenberg-generated verifier contracts (one ~100 KB Solidity file per proof type) are build artifacts, reproducible from the circuits, and are registered into ERC8262Verifier by address at deploy time.

Proving stack

Circuits are written in Noir – the zero-knowledge domain-specific language for SNARK proving systems, maintained by the Aztec Foundation under a dual MIT / Apache-2.0 license – and compiled to on-chain UltraHonk verifiers by Barretenberg (bb), the optimized bn128 elliptic-curve library and PLONK / UltraHonk proving backend maintained by Aztec Labs under Apache-2.0. Pinned versions:

Build

forge build

cd circuits/compliance && nargo compile
bb write_solidity_verifier -b ./target/compliance.json -o ./compliance_verifier.sol

The COMPLIANCE witness in circuits/compliance/Prover.toml matches the Witness Annex in ERC-8262.