Working with computers since 1985. x86 assembler, then C, then C++, then Java. Some scripting (bash et.al.), Javascript/Typescript.
I have a job in the German IT security industry. A lot of cryptography, smartcards, HSMs, firewalls, etc.
I came from MS Windows but am working solely with Linux systems today (SUN/Oracle Solaris in between). My Linux favorites are Debians (Buster, Bullseye, Bookworm).
Recently, I love it to optimize with SIMD (Single Instruction Multiple data) only on AMD64 architectures up to AVX-512.
Favorite cryptographic library was, is, and will ever be: OpenSSL. Almost all of my crypto stuff depends on OpenSSL across PKCS standards, RSA, ECC, Edwards Curves, AES, AES-GCM, etc.