Mocky

Mocky is a simple application for generating custom HTTP responses, aimed at developers who need to test a web service client before the real backend exists, or who want to mock a specific response for a single test case. It lets a developer define a response and get a URL back that returns exactly that response when requested.

It is offered as a free and unlimited hosted service at mocky.io, with a FAQ describing allowed usage, though the maintainer does not guarantee the sustainability or stability of the service. The README notes that self-hosting a private instance was a work in progress at the time of writing, so self-hosting support may be limited or incomplete.

The backend API is written in Scala using the HTTP4s server, with mocks stored in a PostgreSQL database via Doobie, while the frontend is a TypeScript React and Redux application. Mocky is released under the Apache-2.0 license and is currently hosted on Clever Cloud.