I wouldn’t say I did it for fun, but I did do it for the learning experience. My university was very invested in COBOL, and I had classmates who got offers much larger than mine to work for various finance companies in Wisconsin, so I had already learned the basics of language.
It’s hard for me to separate the COBOL from all of the other dysfunctional things going on at the company. I knew that the language was a dead-end and did not want to get stuck with it. Not because I didn’t like the language, but because I was 21 and “Web 2.0” was in full swing and I knew I wanted to do something “cool”.
Migrating data files to new descriptors was always a stressful time. The equivalent of a database schema change, but you had to load the old files and rewrite in the new format largely manually.
The tooling we used felt dated, but worked well enough. Better than the tools we used in school.
I always used “Murach’s Structured COBOL” [1] as my primary reference. Carried that book just about everywhere during that time.
[1]: Murach's Structured COBOL https://a.co/d/hONfFT7