Shipping ZK Circuits? Prove They're Sound.
One under-constrained signal can let anyone forge proofs your verifier accepts. Find the right ZK auditor, the tooling that catches circuit bugs, and learn from real proving-system failures.
Featured Resources
Curated picks from our directory
Top ZK Tools*
- Circom
A domain-specific language and compiler for writing arithmetic circuits used in zk-SNARK proof systems.
- Halo2
Zcash's Rust proving system implementing PLONKish arithmetization with no trusted setup, widely forked across the ZK ecosystem.
- Noir
Aztec's Rust-like language for writing zero-knowledge circuits with a backend-agnostic intermediate representation (ACIR).
- SP1
Succinct's open-source zkVM that proves execution of ordinary Rust programs using a Plonky3-based STARK stack.
- Circomspect
Trail of Bits' static analyzer and linter for circom, detecting under-constrained signals and other circuit anti-patterns.
- Picus
Veridise's automated verifier that detects under-constrained circuits by checking uniqueness of witness outputs.
ZK-Capable Auditors*
- Trail of Bits
Rating: 4.9/5 · Est. 2012
- Veridise
Rating: 4.8/5 · Est. 2021
- zkSecurity
Rating: 4.8/5 · Est. 2023
- Zellic
Rating: 4.8/5 · Est. 2020
- OpenZeppelin
Rating: 4.8/5 · Est. 2015
Notable ZK Incidents
- ZKsync Era (Boojum) $0 (bug bounty)Ethereum L2 · Under-constrained circuit in the Boojum proof system discovered by ChainLight and responsibly disclosed via bug bounty before any exploitation
- Nova (reference implementation) $0 (disclosed)Proof system (generic) · Soundness vulnerability in the Nova recursive folding implementation allowing forged proofs of long computations; reported by researchers and patched
- circom-pairing / Succinct Telepathy $0 (disclosed pre-deployment)Ethereum (light client) · Missing constraint in the circom-pairing BLS signature verification circuits found by Veridise, which would have allowed forged validity proofs
- BNB Chain (BSC Token Hub bridge) ~$570M minted (partially frozen)BNB Chain · Forged IAVL Merkle proof accepted by the cross-chain bridge's proof verification, letting the attacker mint 2M BNB
Real proving-system and verifier failures · Curated from public disclosures
* How we rank: Tools are scored on community adoption (GitHub stars, downloads), active maintenance, detection accuracy, and practitioner recommendations. Auditors are evaluated on public ZK audit track record, depth of circuit and cryptography findings, transparency (public reports), and reputation among security researchers. No firm pays for ranking. See our full methodology.
The Path to a Sound Proof System
Three steps between your circuits and a safe deployment
Why Trust Us
Built on experience, maintained with integrity
Practitioners Since 2017
Built by an infosec practitioner with blockchain security experience since 2017 — including first-audit work on major protocol launches.
No Conflicts
Independent advisory through Savy Advisors LLC. We don't sell ZK audits or run a security firm — our recommendations are unbiased.
AI-Curated
Automated research pipelines track new ZK tooling, circuit bug disclosures, and audit reports so the directory stays current.
Community
Connect with security researchers and practitioners
0xPARC
A non-profit research and development organization supporting applied cryptography and ZK application development, known for programs like ZK learning groups and the ZK Bug Tracker.
Privacy & Scaling Explorations (PSE)
An Ethereum Foundation-supported research lab building open-source zero-knowledge and privacy infrastructure, including Semaphore, MACI, TLSNotary, and zkEVM research.
Zero Knowledge Podcast
The long-running podcast hosted by Anna Rose covering zero-knowledge research, proof systems, and the teams building ZK infrastructure, with an active community around it.