I have 11+ years of professional experience. And, many more "hobby programming" years before that.
I develop C, C++ and Python applications for GNU/Linux, UNIX and "no OS" environments.
I've had my fingers in a variety of things: OS programming (Linux, FreeRTOS, few other research projects), Parallel applications based on MPI, a cross-platform 3D game engine (iOS, Windows, GNU/Linux), Python based web-applications and REST services, Automotive ECUs, Textile machines.