Ask HN: Coding and the Mystical

I learned Prolog this year and it has been nothing short of a mystical experience. In some sense its spoiling other programming languages for me. I marvel how much can be done with so little. I've border line forgotten how to think in loops and mutable states, I want to see everything as unification and resolution, and when I use other languages I'm looking for Prolog-esque solutions. My ordinary thinking has changed too. I find myself wondering "why my backtracking didn't find that solution", and so on. There is a sense in which I actually believe that if something simple explains many things it must be "fundamental" in some way -- or at least partly isomorphic to something fundamental.

What code or maths have you found transformative in this sort of way?