I would not be surprised if TAL is still used for https://www.hpe.com/us/en/servers/nonstop.html boxen.

Similarly, https://www.unisys.com/client-education/clearpath-forward-li... probably still uses its bespoke languages ( https://en.wikipedia.org/wiki/Burroughs_Large_Systems#ALGOL ) in places.

I wonder how much people who still write these languages are paid? I feel like it is one extreme or the other. You are rolling in it or you just don't know any better.

My WAG is that they might have handcuffs of 2x mainstream, but aren't "rolling in it".

Unlike K (or the APLs in general), all these languages are pidgin algol, hence not that difficult to train.

K

Whoa, I work at Crunchy Data. We focus on Postgres, but this K and KX family is wild. Reading about how it is used for Formula 1 data analytics

cf https://t3x.org/klong/ for an even-smaller-audience relative in the family.

poke around the t3x.org domain for more small-audience languages.

Do you have any interest in academic languages?

After a half a century or so without, BCPL recently got floats (for a flight simulator): https://www.cl.cam.ac.uk/~mr10/BCPL.html

I prefer the author's MCPL: https://www.cl.cam.ac.uk/~mr10/MCPL.html but have no idea if anyone is currently using it.

[Edit: looks like Martin backported pattern matching from MCPL into BCPL ca. Oct 2022, so that's recent signs of life for both strains!]

Brainfuck lol

Check "advent of code" solutions. Some of the people invent their own programming languages to solve problems.

JScript is Microsoft's JavaScript that can run server side. I guess it was a thing in the late 90s and early 00s. The "Click Commerce" web CMS/framework was largely written in it. They pivoted from commerce to medical research, and the software is still being used by dozens of institutions.

Z80 assembly.

Pike (https://pike.lysator.liu.se)

Rexx at IBM, but I guess there are several such internal langs used in similar obscure companies.