Architecture
Overview
clearproof is a monorepo spanning four languages:
- Circom — ZK circuit definitions
- TypeScript — Proof SDK, CLI, contract bindings
- Python — FastAPI server, registries, chain interaction
- Solidity — On-chain verifier, registries, compliance recording
Component map
VASP server
The API server collects witnesses from the credential, sanctions, and issuer registries, passes all inputs to the Groth16 prover, evaluates SAR flags, encrypts PII, and assembles the hybrid payload. This is a sequential pipeline, not parallel.
On-chain contracts
ComplianceRegistry is the main entry point. It calls Groth16Verifier for cryptographic verification, checks VASPRegistry for VASP identity and issuer roots, and validates the sanctions root against SanctionsOracle. SanctionsRootRelay receives root updates from a relayer or cross-chain bridge and forwards them to the oracle.
How they connect
Data flow: compliant transfer
Steps 1-6 happen sequentially inside the originating VASP. The SAR review (step 4) evaluates whether the transfer warrants human compliance review — this is advisory only, not an automatic SAR filing. On-chain recording (step 10) can be submitted by either the originating or beneficiary VASP.
See the system diagram for the full visual breakdown of each step.
Hybrid payload
The proof is publicly verifiable. The PII is only readable by the intended counterparty. The envelope binding uses the transfer_id as AES-256-GCM associated data, preventing the encrypted PII from being replayed in a different transfer context.
Security properties
The circuit proves all six properties simultaneously in a single Groth16 proof. They are independent — not sequential.
Click any property to see how the circuit enforces it.