OpenAPI/Swagger explorer with a contract linter

Zero-config OpenAPI (Swagger) 3.x linter: broken $refs, duplicate operationIds, missing responses, undeclared path params, REST naming, security gaps. JSON+YAML, deterministic, runs in CI. A lightweight Spectral alternative.

Centralized OpenAPI quality suite (Spectral rules + Redocly bundle & preview) — portable for any environment.

A curated index of services, tooling, and open source solutions for API testing, mocking, load testing, contract testing, and quality assurance.

Zally is an open source API linter from Zalando that validates OpenAPI 2 and 3 specifications against configurable rule sets for API design consistency. It exposes a REST API, command-line interface, and web UI for checking API designs against Zalando's RESTful API Guidelines or custom rule sets.