OpenSIPS is a mature implementation of a SIP
server/proxy. It is more than a SIP proxy/router,
as it includes application-level functionalities.
OpenSIPS, as a SIP server, can server as the core
component of any SIP-based VoIP solution.
Atomthreads is a highly portable RTOS and scheduler for real time embedded systems. Made up of a few small C files, it can easily be dropped into any embedded system project that needs threading support. Ports to new CPU architectures require a single assembler file.
DeforaOS asm is a modular assembler and disassember framework with support for many architectures (including IA-32, amd64, sparc, and arm), bytecodes (such as Java and Dalvik), and file formats (like ELF, PE, and Dex).