* Languages: C/C++, Python, Matlab, Java, etc.
* Code Manage: Subversion, Mercurial, Trac
* Engineering: Unit testing, Agile development, OOA/OOD, Design Patterns
* Documenting: Doxygen, reStructuredText, Wiki, etc.
* Tools: GNU toolset, Vim, AWK, grep, sed, shell scripts, etc.
* Specialty: Domain-specific languages, API design