I have experience using C# to for backend webserver development, as well as developing Windows desktop applications for use in the transportation industry. Some of my most enjoyable work has been in reworking login systems to be more secure. I've had the opportunity on multiple occasions to redesign a server's login process to remove legacy plaintext login and replace it with more secure BCrypt hashed password systems. I've also discovered and patched CSRF and replay attack vulnerabilities in these same systems.
C/C++
I tend to use C or C++ for personal and school projects. If you're interested in seeing some of my work in these languages, the best place to check out would be my github profile
Assembly
My work collecting old computers and software has led me to develop an interest in assembly languages. Specifically 6502 and Z80 assembly. I've used 6502 assembly to develop games for both the Commodore 64 and the Nintendo NES. I use Z80 assembly to write small programs for a Z80 computer that I built myself.
Other langauges
I also have experience writing in python, java, and a little javascript.