What we still need to verify : 2 points in this profile are not yet confirmed against vendor documentation.
- Exact scope of the free tier versus paid platform features: confirm with vendor
- Current list of supported CI systems and IDEs: verify against vendor docs
Treat these points as unconfirmed. They are open items in the catalog's verification queue, and this note stays until each is checked against the vendor's documentation.
What it does
42Crunch treats the OpenAPI definition as the security artifact. Its audit engine parses a definition and runs it against a large library of checks covering authentication declarations, transport settings and data shape constraints: whether every operation declares a security scheme, whether response schemas are tightly typed or fall back to free form objects, whether string fields carry length and pattern limits. Findings are pinned to specific lines of the definition, so a developer sees the problem in the file they are editing rather than in a separate report.
The second stage checks whether the running API matches the contract it claims. The conformance scanner generates requests from the definition, both valid ones and deliberately malformed ones that violate declared types, lengths and required fields, then compares what the live endpoint returns against what the spec promised. A parameter documented as an integer that happily accepts a string surfaces as a conformance gap. The third stage is an API firewall that enforces the same contract in front of the service, deployed as a container or sidecar, rejecting traffic that falls outside the schema.
Where it fits
The audit runs earlier than anything else in API security tooling, on a developer's laptop through an IDE plugin and again on pull requests, because it needs only the definition file. Conformance scanning needs a deployed instance, so it sits in the pipeline after a build lands in a test environment. The firewall is a runtime deployment owned by platform or operations. The hard prerequisite is a maintained OpenAPI definition for every service. If your specs are generated once and then diverge from the code, the whole chain loses its footing.
Strengths
- Design time feedback catches weak schema and missing authorization declarations before any code exists.
- Conformance scanning tests the gap between documented and actual behavior, which most scanners never look at.
- One contract drives audit, scan and runtime enforcement, so there is a single source of truth instead of three rule sets.
- Positive security enforcement blocks malformed input by default rather than matching known attack patterns.
Limitations
- Contract driven by design, so undocumented and shadow endpoints are invisible. It does not discover APIs from traffic.
- Strict audit rules produce long finding lists against real world specs, and teams spend real effort tightening definitions first.
- The firewall adds a component to the request path, with the operational and latency considerations that implies.
Who it suits
Teams practicing design first API development, where the specification is written before the implementation and kept authoritative. Organizations whose API estate is largely undocumented should pair this with traffic based discovery, or start there instead.
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