[larve]

my personal favourite: seeing the foldable (a monoid with two types, kind of) in event driven systems means you can model a lot of your embedded software / web applications as a set of functional state/event reducing functions, and build a clean system right from the get go. Seeing the functors in there tells you which part of the state can be split, parallelized or batched for performance or modularity).

Again, these are all very possible without knowing category theory, but category theory studies what the abstractions behind this could be. I find that the huge amount of intuition (driven by some formalism picked up along the way, but even more so by just writing a lot of code) I developed is reflected in what I see in category theory. It's why I genuinely think that web development is just like embedded development: https://the.scapegoat.dev/embedded-programming-is-like-web-d... which seems to be way more controversial than I thought it would be.