pump.io : Social server with an ActivityStreams API. It's a stream server that does most of what people really want from a social network.
apiato : apiato is a starter project, designed to help you build scalable API’s faster, by providing tools and functionalities that facilitates the development...
mountebank : mountebank is the first open source tool to provide cross-platform, multi-protocol test doubles over the wire. Simply point your application under tes...
RSS Box : This app uses the API of other websites and gives you an RSS feed in return. Quick and simple.
Cool QL Cool : CoolQLCool (CQC) is an open source GraphQL server that allows you to turn websites into GraphQL APIs.
Bluepine is a DSL for defining API Schema/Endpoint with the capabilities to generate Open API (v3) spec, validate API request and serialize object for API response based on single schema definition.