I wrote my first programs (in BASIC or PL1) in 1970, so yes, I'm an old fart.

At last count I've coded in over 50 languages, at least 16 operating systems (counting all variations of Linux as one OS, all variations of Unix as one, etc.), and probably a couple dozen hardware platforms. The first Mainframe I used had 64 KB of RAM and the largest drive on it was 33 MB (16 bit addressing). The user area in RAM limited your combined code and data to 20,424 bytes. Oh, and your disc file buffers came out of the 20,424 bytes, so you really didn't want to open many files.

I spent years in OS work. Yup, the stuff where you work with low-level languages, assembly, etc. It was fun. Desk checking was a must. One typo and the system went down, the 32 users were streaming, and you were reading a memory dump.

I also spent time with OS networking code. This was in the days before routers, switches, TCP, etc., where you had leased lines connecting computers (gateways) and you wrote your own software to move data around your network. LOL, I doubt any of the papers I gave at international conferences were ever copied from paper publications to electronic form.

Then I co-founded what was called a third-party software house. We sold our software mainly to Fortune 100 customers, and had customers on five continents, in Banking, Media, University, Government, and various other industries. My divorce led to the end of that, but we had a 15+ year run of it.

Since then I've worked on various contracts, for what at the time was the worlds largest Internet Service Provider, etc. Today I'm mostly in business intelligence, writing SQL and quite a bit of code.

I'm on emacs.stackexchange.com because I'm getting back into Emacs. Today I'm running version 25.3.something on Windows 10, but I first used Emacs (technically "Micro Emacs") in 1985 on the HP 150 Touchscreen Graphic PC. It is sad to say, but that MS DOS 2.11 Intel 8088 processor based PC was such a great Micro Emacs platform that it took considerably more than a decade for a better Emacs platform to replace it. Execute Emacs commands by touching the screen, and in 1985.

John