Yes, we still have a TUI to our core CMDB and billing. With 500+ employees, not everybody is happy with it, so we also built an API and a web app to access and manipulate the most central data.

But, we also have some power users who absolutely swear by it, and we offer some power user features for them :-)

* full readline integration, so there's a command history, Ctrl-R reverse search in the command history etc.

* tab completion for many prompts

* a generic system where outputs can be redirected to a pager, a physical printer, "wc" (word count), into a file etc.

* tabular data also has an alternative CSV representation

* generic fast-jump into menus. This works by supplying commands on the command line, and transitioning to interactive mode when the command list has run out

This is all built in-house; the first git commit is from 1997 but that was "import from CVS" and already 20k LoC, so the actual origins go back further.

It's written in Perl with no framework, just libraries.

I think you are about a decade off on your first git commit, unless you meant they went cvs -> svn or something and then ended up on git later.