* '''Not properly languages''': SQL, HTML, CSS, LaTeX, GNU make.
* '''Operating systems''': Linux (Red Hat, Fedora, Ubuntu, SuSE, Debian), Mac OS X, Solaris (versions 6 to 9),
- NetBSD, AmigaOS, Windows (NT, WIN32 and WIN16).
+ NetBSD, AmigaOS, Windows.
* '''Frameworks/APIs''': POSIX, Qt, Gtk, STL, Boost, WIN32, MFC.
* '''Programming Techniques''': OOP, generic programming, metaprogramming, real-time, event-driven, multithreading.
* '''Development Tools''': GCC toolchain, GNU make, auto-tools, MSVC, XCode, Codewarrior, IAR, Code Composer Studio, BSO Tasking.