I understand that R is single-threaded and it does not support concurrent requests. This is the same issue when we use rplumber:
R is a single-threaded programming language, meaning that it can only do one task at a time. This is still true when serving APIs using Plumber, so if you have a single endpoint that takes two seconds to generate a response, then every time that endpoint is requested, your R process will be unable to respond to any additional incoming requests for those two seconds.
What about rapache? Does it support concurrent requests? Can I use rapache as a server for rplumber or jug?