WireMock : Free and Open Source tool for building mock APIs. Create stable development environments, isolate yourself from flakey 3rd parties and simulate APIs t...
Mockbin : Mockbin allows you to generate custom endpoints to test, mock, and track HTTP requests & responses between libraries, sockets and APIs.
DuckRails : DuckRails is a development tool.
Its main purpose is to allow developers to quickly mock API endpoints that for many possible reasons can't reach at a...
Postal : Postal is a complete and fully featured mail server for use by websites & web servers. Think Sendgrid, Mailgun or Postmark but open source and ready f...
Grafana k6 : Grafana k6 is an open-source, developer-friendly, and extensible load testing tool. k6 allows you to prevent performance issues and proactively improv...
Mockoon is the easiest and quickest way to design and run mock APIs. No remote deployment, no account required, free and open-source.