My experience with OCaml has transformed how I think about programming and complex system design. This may also be true if you learn any other functional programming language, but OCaml is easy and flexible which makes it good imo as a door towards the more formal part of comp sci. Even for steering an LLM I think this might help.

My experience with lisp was exactly that: it completely changed how I think about programming, but much more, how I think about systems and engineering. (I learned it through SICP)