I mean, the modern language of algebraic geometry and homotopy theory is based on advanced category theory. David Spivak, the author of this book, wrote a great

I mean, the modern language of algebraic geometry and homotopy theory is based on advanced category theory. David Spivak, the author of this book, wrote a great thesis on cobordisms and used categorical techniques to sidestep hard problems in intersection theory. You can also look at some of Ezra Getzler’s work to see how setting up clean categorical abstractions can make it easier to attack hard problems in geometry. In CS, abstractions like monads and effect handlers come from category theory. Plotkin and Power did a lot of super technical work on syntax/semantics adjunctions while sorting out the foundations of effect handlers.