With your push-pull algorithm, were you considering that the graph had already been built up, e.g. by an earlier pull phase? And the push-pull bit is just for subsequent updates? If so, then I think I'm following :).

I've been working in the context of reactivity on the backend where you're often loading up the calculations "from scratch" in a request.

I agree with your monad analogy! We looked into using something like Rx in the name of not reinventing the wheel. If you build out your calculation graph in a DSL like that, then you can do more analysis of the graph structure. But as you said in the article, it can get complicated. And Rx and co are oriented towards "push" flows where you always need to process every input event. In our context, you don't necessarily care about every input if the user makes a bunch of changes at once; it's very acceptable to e.g. debounce the end result.