Akka HTTP
The Streaming-first HTTP server/module of Akka
...Akka HTTP follows a rather open design and many times offers several different API levels for “doing the same thing”. You get to pick the API level of abstraction that is most suitable for your application. This means that, if you have trouble achieving something using a high-level API, there’s a good chance that you can get it done with a low-level API, which offers more flexibility but might require you to write more application code. Akka HTTP has been driven with a clear focus on providing tools for building integration layers rather than application cores. As such it regards itself as a suite of libraries rather than a framework.