UNIX-like reverse engineering framework and command-line toolset
Capstone disassembly/disassembler framework
Unicorn CPU emulator framework (ARM, AArch64, M68K, Mips, Sparc
Tools for BPF-based Linux IO analysis, networking, monitoring, etc.
Next Scripting Framework (NSF)
The best library to work with .Net Assemblies in any programming lang.
PHP bindings for the cross-platform GUI library wxWidgets.
Universal programmer/debugger. Universal embedded software framework.