[zemptime]

I did try ruby-prolog. The deeper issue is that its just not prolog. Writing in actual prolog affords a lot of clarity and concision which would be quite noisy in ruby-prolog. To me, the difference was stark enough it wasn't worth any convenience already being in ruby was worth.

[dragonwriter]

Porolog might be more to your liking.

https://www.rubydoc.info/gems/porolog#porolog-wiki