npm · Packagist99Exceptionalhealth index

swagger-api/swagger-uiSwagger UI is a collection of HTML, JavaScript, and CSS assets that dynamically generate beautiful documentation from a Swagger-compliant API.
JavaScript★ 29K↓ 49.8M/moSep 16, 2026
npm98Exceptionalhealth index
JavaScript · TypeScript★ 9,461↓ 49.5K/moAug 28, 2026
npm96Exceptionalhealth index
JavaScript★ 2,694Aug 27, 2026
npm94Exceptionalhealth index
TypeScript★ 100↓ 24.5M/moOct 12, 2026
Go91Excellenthealth index
Go★ 1,358Sep 14, 2026
PyPI90Excellenthealth index
Python★ 1,988Sep 14, 2026
npm · PyPI88Excellenthealth index

counterfact/api-simulatorTurn an OpenAPI spec into a local API in one command. Build and test your frontend with custom responses, shared state, and simulated failures, without waiting for the backend.
TypeScript · JavaScript · Astro★ 170↓ 28.2K/moSep 18, 2026
Go88Excellenthealth index
Go★ 4,354Aug 28, 2026
npm · Go88Excellenthealth index

daveshanley/vacuumvacuum is the worlds fastest and most versatile OpenAPI, AsyncAPI & JSON Schema linter, docs generator and toolkit. It tears through API specs at light speed. 100% compatible with Spectral rulesets, and OpenAPI 3.0, 3.1 and 3.2
Go★ 1,124↓ 160.5K/moSep 11, 2026
npm88Excellenthealth index
TypeScript★ 7↓ 1.3M/moOct 21, 2026
PyPI87Excellenthealth index

python-openapi/openapi-coreOpenapi-core is a Python library that adds client-side and server-side support for the OpenAPI v3.0 and OpenAPI v3.1 and OpenAPI v3.2 specification.
Python★ 369↓ 3.8M/moAug 27, 2026
Go86Excellenthealth index

pb33f/libopenapilibopenapi is a fully featured, high performance OpenAPI 3.2, 3.1, 3.0, Overlays and Arazzo parser, library, validator and toolkit for go applications.
Go★ 874Sep 10, 2026
PyPI86Excellenthealth index

python-openapi/openapi-spec-validatorOpenAPI Spec Validator is a CLI, pre-commit hook and python package that validates OpenAPI Specs against the OpenAPI 2.0 (aka Swagger), OpenAPI 3.0 and OpenAPI 3.1 specification.
Python★ 407↓ 40.6M/moAug 27, 2026
Packagist · npm86Excellenthealth index

studio-design/gessoGesso — OpenAPI 3.0/3.1/3.2 contract testing for PHP. Framework-independent core with Laravel, Symfony, Pest, and PSR-7 adapters. PHPUnit coverage, request/response validation, fuzzing, and drift detection.
PHP★ 10↓ 3,490/moOct 22, 2026
Go84Excellenthealth index

ehabterra/apispecAPISpec - Generate OpenAPI 3.1 specs from Go code with intelligent framework detection and call graph analysis. Supports Gin, Echo, Chi, Fiber, and net/http.
Go★ 85Sep 12, 2026
crates.io84Excellenthealth index

juhaku/utoipaSimple, Fast, Code first and Compile time generated OpenAPI documentation for Rust
Rust★ 4,102↓ 11.6M/moSep 23, 2026
npm · Go84Excellenthealth index

marle3003/mokapiYour API mocking tool for OpenAPI and AsyncAPI using Go and JavaScript - https://mokapi.io
Go · Vue★ 58↓ 4,133/moOct 22, 2026
Go84Excellenthealth index

speakeasy-api/openapiA set of packages and tools for working with OpenAPI, Swagger, Arazzo and Overlay Specification documents.
Go★ 276Sep 23, 2026
RubyGems83Excellenthealth index

ahx/openapi_firstopenapi_first is a Ruby gem for request / response validation and contract-testing against an OpenAPI API description. It makes APIFirst easy and reliable.
Ruby★ 221Sep 11, 2026
PyPI83Excellenthealth index
Python★ 21↓ 161.1K/moSep 26, 2026
npm81Excellenthealth index

sourcey/sourceyPrecision documentation from OpenAPI, MCP, Doxygen, and Markdown guides. Static HTML you own.
TypeScript★ 1,369↓ 6,916/moSep 12, 2026
npm80Excellenthealth index
TypeScript · Vue★ 255↓ 87K/moSep 13, 2026
Python★ 126↓ 26.7M/moAug 27, 2026

erraggy/oastoolsOpenAPI Specification (OAS) tools for validating, parsing, fixing, converting, diffing, joining, and building specs; as well as generating client/servers/types from specs.
Go★ 5Sep 20, 2026

oaswrap/spec⚡A lightweight, framework-agnostic OpenAPI 3.x specification builder for Go.
Go★ 118Sep 18, 2026

yhnavein/swaggieTool for generating TypeScript client code for given Swagger API endpoints
TypeScript★ 26↓ 15.9K/moOct 22, 2026

mockzilla/mockzillaOpen-source OpenAPI mock server with cloud hosting and local modes for development, testing, and CI. Generates realistic API responses from specs with latency simulation, error injection, proxy fallback, and request validation. Validated against 2,200+ real-world OpenAPI specs.
Go★ 106Sep 19, 2026
npm · Go73Goodhealth index

pb33f/openapi-changesThe world's most powerful OpenAPI breaking changes detector. Discover what changed between two OpenAPI specs, or a single spec over time. Supports OpenAPI 3.2, 3.1 and 3.0
JavaScript · Go★ 358↓ 86.1K/moSep 29, 2026
Go · Go Template★ 1Sep 13, 2026

pb33f/doctorThe Doctor. Just the doctor, no more, no less. The OpenAPI all in one supercharged go toolkit
Go · TypeScript★ 42Oct 20, 2026