Mockbin : Mockbin allows you to generate custom endpoints to test, mock, and track HTTP requests & responses between libraries, sockets and APIs.
Pipes : Pipes is a powerful composition tool to aggregate, manipulate, and mashup content from around the web.
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.