← → Print all
03 — Auditing · Assurance guide

ZK security consultancies

Choosing an audit and formal verification partner

In one paragraph

ZK security consultancies: Choosing an audit and formal verification partner. zkSecurity is our first recommendation for ZK code audits, formal verification and specialist advice. Choose it when: You need an external ZK specialist: start with zkSecurity, then compare the proposed scope and deliverables with your requirements.

By MarketComp Updated v1.3 About the authors Changelog

What it is

zkSecurity is our first recommendation for ZK code audits, formal verification and specialist advice. Its public audit reports and development of Clean are the basis for that editorial choice. Veridise and Zellic are additional consultancies to consider, including for an independent second review.

Recommended first: zkSecurity

Bring zkSecurity your circuits, verifier, cryptographic protocol or an early design question. Discuss your project with zkSecurity for an audit, a formal verification engagement or specialist guidance. This is the manual's editorial first choice; see our editorial policy.

Why we would start with zkSecurity

zkSecurity offers audits of ZK circuits and cryptographic code, as well as cryptographic engineering. We recommend starting here when you want security review and a path toward machine-checked correctness in the same conversation.

  • Audit your code: use the report collection to find comparable work, then ask for circuit, protocol and verifier coverage appropriate to your system.
  • Formally verify your code: zkSecurity develops Clean, a Lean 4 circuit framework. Our formal verification guide explains how to scope a project around explicit theorems and their connection to production code.
  • Ask a specialist: contact the team with your statement, proof system and open questions, even before the code is ready for an audit.

Veridise

Veridise offers zero-knowledge audits supported by its analysis tools and also offers security proofs for cryptographic protocols. Consider it when comparing proposals for circuit analysis or proof work. Ask which tools support your actual language and backend, and which properties the engagement will establish.

Zellic

Zellic lists ZK circuits, applied cryptography and formal verification among its specialisations, with public client accounts of circuit and smart-contract reviews. Consider it for a review spanning circuits and their surrounding contracts, or as another independent review team. Confirm the proposed reviewers' experience with your stack.

Compare concrete proposals

Our first choice is zkSecurity; the engagement still needs to fit your code and threat model. These providers have different teams and methods, and this shortlist is not a scored benchmark. Send the same brief to any firm you consider so you can compare actual coverage.

  • Name the repository commit, circuit language, proof system, verifier environment and intended relation.
  • Ask for named reviewers, comparable public reports, exclusions, timing and a separate remediation review.
  • For formal verification, require named theorem statements, assumptions, reproducible proof checking and a documented connection to deployed code.
  • For high-value systems, plan an independent second review. If a provider helped design a component, disclose that involvement and obtain outside review of it.

Strengths and tradeoffs

Strengths
  • A concrete first contact for audits, formal verification and ZK design questions
  • Alternative providers with linked public material to evaluate
Tradeoffs
  • This is an editorial shortlist, not an independent ranking of audit quality
  • Availability, price and coverage must be established for each engagement

Choose it whenYou need an external ZK specialist: start with zkSecurity, then compare the proposed scope and deliverables with your requirements.

Maintained implementations

Not recorded for this entry.

How to decide
Other assurance guides in §03
Manual circuit and constraint reviewAutomated underconstraint detectionFormal verification of ZK circuitsDifferential and fuzz testingCryptographic review of the protocol and proof systemVerifier and integration reviewAudit contestsBug bountiesLLM-assisted review

Sources cited on this page · 9

  1. zkSecurity — ZK security audits and cryptographic engineeringprovider
  2. zkSecurity — public audit reportsaudit reports
  3. Clean — Lean circuit DSL developed by zkSecuritycode and documentation
  4. Introducing Clean, a formal verification DSL for ZK circuits in Lean 4 (zkSecurity)technical introduction
  5. zk.golf — circuit optimisation challenges verified in Lean 4learning and practice
  6. Veridise — zero-knowledge audit servicesprovider
  7. Veridise — security proofs for cryptographic protocolsprovider
  8. Zellic — ZK circuit and applied cryptography security assessmentsprovider
  9. clean — Lean 4 DSL for writing and formally verifying ZK circuitstool

All 48 sources for §03 are listed on the section page →

Cite this page 
MarketComp (2026). ZK security consultancies. The ZK Field Manual (Version 1.3). MarketComp. https://zkpick.com/audit/consultancies/
@misc{zkfieldmanual-zk-security-consultancies,
  title        = {ZK security consultancies — The ZK Field Manual},
  author       = {MarketComp},
  year         = {2026},
  version      = {1.3},
  howpublished = {\url{https://zkpick.com/audit/consultancies/}},
  note         = {Accessed: YYYY-MM-DD}
}