Writing a C++11 program to take curl requests

I want to write a simple program (in C++11) that can recieve data from curl commands. In a language like python, I would probably write a flask app to listen for requests like curl "localhost:5000" -H "Content-Type: application/json" -d '{"user_1": "alice", "user_2":"bob"} for example. What libraries / what do I need to do to write a program that can take a string from a curl request and input it into my C++ program? Are there any links or wikis that you can direct me to to learn about how to write something like this? Thanks, and sorry for the high-level question.

I tried using crow but I couldn't get it to install properly. If someone can help me with setting up crow, I'll be happy.