Curie is a very minimalistic, tiny C library. It supports basic I/O, basic networking, S-expression based I/O, signal handling, process handling, and I/O multiplexing. If the target architecture is explicitly supported, statically linked binaries may be as small as 4-20 kilobytes; if not, then it only relies on the host's C library. The library explicitly does not provide a POSIX interface so that it may be used in conjunction with a regular host libc (or without one).
GraphicsMagick is a robust collection of tools and libraries which support reading, writing, and manipulating an image in over 90 major formats including popular formats like DPX, DICOM, BMP, GIF, JPEG, JPEG-2000, PDF, PNG, PNM, SVG, and TIFF. A high-quality 2D renderer is included, which provides a subset of SVG capabilities. C, C++, Perl, Tcl, and Ruby are supported. Originally based on ImageMagick, GraphicsMagick focuses on performance, minimizing bugs, and providing stable APIs and ABIs. It runs on all modern variants of Unix, Windows, and Mac OS X.
BACnet is an implementation of the BACnet (Building Automation and Control Networks) protocol specifically tailored for embedded systems. BACnet itself is a standard routable protocol designed to handle communications in automation in buildings, such as air conditioning systems and other HVAC equipment.