Hoppscotch Community Edition is an open-source API development and testing tool for REST, GraphQL, WebSocket, SSE, MQTT, and Socket.IO with collections and environments.

80.1k stars6.1k forksMITlast commit Actively maintained

Stoplight is a cloud API design and governance platform for creating and editing OpenAPI and JSON Schema specifications, generating interactive API documentation and mock servers, validating API style/rules, and supporting collaboration and API lifecycle workflows.
Hoppscotch Community Edition is an open-source API development and testing tool for REST, GraphQL, WebSocket, SSE, MQTT, and Socket.IO with collections and environments.

80.1k stars6.1k forksMITlast commit Actively maintained
Open source architecture documentation tool to model and document domains, services, events, and schemas for event-driven and microservice systems.

2.8k stars272 forkslast commit Actively maintained
SQLPage is a fast SQL-only web app builder that turns .sql files into interactive web pages and APIs on top of your existing database.

2.5k stars177 forksMITlast commit Actively maintained
Yaade is a self-hosted, collaborative API development environment that lets teams share API collections, run tests, and import from OpenAPI or Postman.

2k stars89 forksMITlast commit Slowing down
Every option on this page is open source and free to run on your own hardware, so you own the data and there is no subscription to cancel. 3 of 4 shipped a commit in the last six months. Licences in this list: MIT. In exchange you take on hosting, backups and updates yourself.
Browse everything in API Development, Mocking & Testing.