I've been using Unix on and off for 20 years, and I've done a bunch of Unix development work here and there (and more than just "did some programming and it was on a Unix system") - but I've no idea how to write a bash script, or a zsh one, for that matter.

If I need to automate something, I use a GNU Makefile, or Python. That way it works on Unix as well as on Windows...