C/Invoke is a library which can call C functions at runtime with no prior knowledge of the function prototypes. This capability is used to allow any language to call native libraries without writing a separate module in C, similar to the P/Invoke functionality of the .NET framework.
cqueues is a comprehensive event and networking library for Lua 5.2 and LuaJIT using modern Unix O(1) polling facilities. It includes libraries for buffered socket I/O, SSL/TLS sockets, DNS querying, signal handling, threading, file change notification, and X.509 key management. It natively supports Linux, *BSD, OS X, and Solaris systems without third-party dependencies, and is interoperable with any event loop that accepts plain descriptors, or is usable standalone.