Have tutored in both Ruby and Python before at beginner to intermediate level. Happy to teach using TDD (I use rspec on Ruby and py.test on Python).
Regularly use Ubuntu/OSX/Windows7 for cross-platform development.
Lead Programmer for 2x2 Games for 6 months, working on Unity of Command 2 (laid off, sadly) - Python, Cython, SDL2, OpenGL, GLSL. Many small projects as a freelance developer before and after this (Python and Ruby).