Choose the audit firm that best matches your chain, runtime, protocol risks, and exact code scope—not the one with the biggest name or lowest quote. Verify who will do the work, inspect comparable reports, and agree in writing on remediation and retesting. An audit assesses a defined revision using an agreed scope and methods; it cannot guarantee vulnerability-free code.
1. Define exactly what the audit must cover
Before requesting proposals, create a review brief that gives every firm the same target. Include the target chain and runtime, protocol architecture, assets at risk, planned deployment date, repository and exact commit, known concerns, budget range, and any specific requirement such as formal verification or jurisdiction-specific work.
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List the components explicitly: contracts, libraries, deployment configuration, oracle integrations, privileged roles, governance paths, and external services. State what is excluded. Reviewing your integration with an external protocol does not automatically mean the external protocol itself is in scope. The agreed source revision and boundaries determine what the audit can meaningfully assess; see OpenZeppelin’s guide to choosing a smart-contract auditor and Ethereum.org’s smart-contract security guidance.
Use a reproducible source reference, such as a repository commit hash, rather than a moving branch name. If code or configuration changes during the engagement, ask how the change will be handled and whether it requires additional review.
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2. Match expertise to your chain and threat model
A firm’s general reputation is not a substitute for experience with your system’s language, runtime, assets, trust boundaries, and attack surface. Ask for published work on the target chain and protocol designs comparable to yours. Identify the actual reviewers—not just the firm—and request recent client references for similar systems.
Look for relevant experience with the risks your design creates. A protocol involving oracles, upgrade controls, bridges, complex accounting, or governance needs reviewers who understand those mechanisms and how they interact. Ask what each named reviewer will contribute, their availability, and who is responsible for technical sign-off.
3. Read reports for evidence, not just a clean summary
Where public examples are available, inspect two or three reports from the same technology stack. A useful report lets you understand what was examined and how the reviewers reached their conclusions.
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- Scope and revision: Are the reviewed components, source revision, exclusions, and limitations clear?
- Root cause: Does each finding explain the underlying flaw and its impact, rather than merely label a symptom?
- Reproducibility: For severe issues, does the report provide convincing proof-of-concept evidence or a clear way to reproduce the problem?
- Remediation tracking: Does it show the team’s response and the status of each finding?
- Retest record: Is there evidence that fixes were checked, and is the final status clear?
A report with no findings means that no issue was reported within its scope and process. It is not proof that the code is safe.
4. Understand how the firm will look for defects
Ask how manual review relates to static analysis, fuzzing, symbolic execution, and formal verification where appropriate. Tools can supplement expert reasoning; what matters is whether the team explains which protocol-specific risks and invariants it will test and how the methods fit together.
For example, Hacken publishes a Smart Contract Code Review And Security Analysis Methodology, version 3.0 dated June 16, 2026. It is a vendor-authored example of a published methodology, not independent evidence that one provider outperforms another.
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5. Set remediation and retesting terms before signing
Clarify what happens after the initial findings arrive. Confirm whether the schedule and fee include implementation questions, responses to disputed findings, fix verification, final report updates, and how many retest rounds are included. Establish what happens if you change features or dependencies, or if an issue is found after the engagement ends.
Ask the firm to distinguish findings marked resolved—addressed in the reviewed change—from those marked acknowledged, which may have been accepted or noted without being fixed. A change made after the reviewed revision can fall outside the original scope, so agree on how further changes will be assessed.
6. Choose the review model that fits the work
A private audit assigns a team to a defined scope and delivers a report. A competitive review platform brings multiple independent reviewers or contestants to examine code. As a practical heuristic, contests may suit broader code-level bug finding, while a private firm may better suit sustained protocol-design review. Some high-security teams use both. This is a way to match a delivery model to a need, not a universal guarantee of results; Ethereum.org’s security guidance discusses smart-contract security practices in ecosystem context.
When comparing models, consider whether your main need is a continuing design conversation, independent code-level review, or both. Make sure each proposal states the scope, deliverables, reviewers, and retesting assumptions so the model itself does not obscure what you are buying.
7. Put incident history in context
When checking a firm’s record, compare any public incident attribution with the specific contract, audited scope, and timing. A later governance change, upgrade, or operational key compromise is not automatically evidence that the auditor missed an in-scope code defect. Conversely, a clean public record is only one signal: it may reflect a smaller or lower-risk client sample.
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1Scan for outdated or missing drivers - takes under a minute2Repair Windows errors before they cause bigger problems3Fix the driver behind crashes, sound loss and screen glitchesAvoid ranking providers from a single exploit leaderboard or a self-reported rating. Incident history can inform questions about scope and process, but it does not replace review of the firm’s people, relevant work, reports, and terms.
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8. Compare proposals on identical terms
Send multiple firms the same revision and scope, and ask them to quote the same deliverables, reviewer seniority, schedule, disclosure terms, and retesting assumptions. The available evidence does not establish a reliable market-wide price benchmark, so a quote is useful only in relation to what it covers.
Do not choose the cheapest firm without checking its capability on your target stack. A very low bid could reflect a narrower or more automated review, but that should be tested against the actual proposal—not assumed from price alone. Compare each offer across the same criteria:
Quick Recap
- Chain and runtime fit, plus experience with comparable protocol designs
- Named reviewer seniority, availability, and relevant client references
- Scope, exclusions, manual and tool-assisted methods, and report examples
- Remediation, retesting, schedule, disclosure terms, and total proposal price
- Private, competitive, or combined delivery model
Questions to ask before hiring
- Who specifically will review the code, and what have they reviewed on this chain and protocol type?
- What repository commit and components are in scope? What dependencies, integrations, deployment settings, privileged roles, and governance paths are excluded?
- How do you combine manual review with static analysis, fuzzing, symbolic execution, and formal methods where applicable?
- Can we inspect reports for comparable systems, including scope, proof-of-concept evidence, remediation history, and retest sign-off?
- How are disputed findings handled, and what happens when a finding is reported after the engagement ends?
- Does the proposal include retesting fixes? How many rounds are included, and which changes require new scope?
- Can you provide recent references from clients with similar protocols?
- What are the confidentiality, disclosure, and public-report terms?
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