Really, that's quite likely, but I don't actually know of any myself, so I chose to keep it to software that I (1) knew about and (2) others did as well. It's

Really, that's quite likely, but I don't actually know of any myself, so I chose to keep it to software that I (1) knew about and (2) others did as well. It's worth pointing out (because I'm a Lisp nerd) that there is a decent amount of Lisp code that is still executable today that was written a long time ago. In terms of software systems, https://en.wikipedia.org/wiki/Maxima_%28software%29 https://en.wikipedia.org/wiki/Maxima_%28software%29 is the one I know about; there might be quite a few others I don't know about. Also, I've gotten the impression that there is some sort of slow move to Java/.NET from the COBOL systems.