httpuv

httpuv provides low-level socket and protocol support for handling HTTP and WebSocket requests directly from within R. It uses a multithreaded architecture where I/O is handled on one thread and R callbacks are handled on another.

This package is primarily intended as a building block for other packages rather than for creating complete web applications directly. It can serve static files entirely within the I/O thread without blocking R, and it supports WebSocket connections in addition to standard HTTP requests. httpuv is built on top of the libuv and http-parser C libraries for reliable, high-performance network communication.