RESTinio
HTTP/WebSocket server C++14 library
...Consider the task of writing a C++ application that must support some REST API, RESTinio represents our solution for that task. Server runs on the main thread, and responds to all requests with a hello-world message. Of course, you've got access to the structure of a given HTTP request, so you can apply complex logic for handling requests. Async request handling. Cannot get the response data immediately? That's ok, store the request handle somewhere and/or pass it to another execution context and get back to it when the data is ready.