Shameless plug: I’ve been working on some open-ended state-machine-like constructs in Clojure and JavaScript - https://github.com/notduncansmith/factfold https:

Shameless plug: I’ve been working on some open-ended state-machine-like constructs in Clojure and JavaScript - https://github.com/notduncansmith/factfold https://github.com/notduncansmith/factfold The idea is to capture the useful properties of state machines without being constrained to enumerable states. I’m currently working on a program to edit these machines visually.