Very interesting.

Are there PLs that support this kind of thing at the language level as you are describing?

https://colcarroll.github.io/ppl-api/ is likely a good starting point to get a taste of examples in Python; some use custom languages, but the success of Python-native frameworks in the LLM world I think has shown that embracing that makes interop and composability more possible at scale.

https://news.ycombinator.com/item?id=28941145 has some discussion here as well, though it’s a few years old.

Pyro and NumPyro seem to be popular at the moment!

If you're willing to be discrete about it, logic languages like Prolog and Mercury use "unification" instead of "evaluation" which means they can evaluate backwards.