Higgs.IO is a high performance, message oriented network library built for realtime systems. It provides a core extensible framework and libraries built on top of the core. Libraries include a WebSocket server, an HTTP server and client, and Boson, a custom serialization and RMI library.
Monkey HTTP Daemon is a very fast and lightweight Web server for Linux. It uses a hybrid networking model based on asynchronous calls (event-driven) and fixed threads, which makes it scalable and capable of attending thousands of clients per second. It provides a powerful API for C and is ideal for embedded devices, thanks to its small core and plugin architecture.