I used to work at Epic, but it was over six years ago at this point. Their entire stack at the time was MUMPS and VB6. No idea if that's still the case, mind you -- there were some modernization efforts underway when I left. Although from what my friends that work at Epic hospitals tell me about their software, it likely hasn't changed much.

And I almost certainly got hired there because I actually knew MUMPS from a previous job. Of the developers they hired during my cycle, every one of them was on an H1-B or fresh out of Carnegie Mellon or MIT; meanwhile I was a kid with a sub-3 GPA from a liberal arts school with a Political Science degree.

(If you do some light searching, you can find another famous story on TDWTF that I wrote about MUMPS.)