The Mercury logic programming system (github.com)

Oh wow, Zoltan was one of my lecturers at UniMelb, and in one semester we were tasked with learning his Mercury language. So good to see it thriving still.

The closest that I could find to a "what the fuck is this?" page is:

https://www.mercurylang.org/about.html

There are files in this repository that were last touched 32 years ago. Any reason to be posting it now?

Last release was in 2023.

It is effectively dead.

This is a terrible shame, because this would have been an nice modern alternative to Prolog.

prince, a high quality html renderer used for typesetting, is written in mercury:

https://www.princexml.com/doc/acknowledgements/

Something you might find interesting to look at is Rego, a datalog-derived language been used for writing security policies. Rego is dynamically typed, so no real protection. It's input is basically JSON and it can apply JSON-Schema, but that's it. I think it would be interesting to look at Rego as a restricted version of this and see what types buys for a Rego user. It's probably one of the larger areas of logic programming and has brought people into the fold, so to speak.