I have been using UNIX since I was 7. It all started with a copy of The Waite Group’s UNIX Primer Plus and an account on grex, which at the time was a SunOS 4 box that gave out free shell accounts, accessible via Telnet! Next came Linux, and then FreeBSD, and then Mac OS X, and then Linux again. Meaning, Arch.
I was an early adopter of FreeBSD/amd64, in the Athlon64 3200+ days, and through FreeBSD source and The Design and Implementation of (4.4BSD|FreeBSD) series of books, independently studied… the design and implementation of operating systems. I remain a staunch advocate for the UNIX and C philosophies, including as they are carried on in modern languages like Go and Rust.