Category theory often sounds like impenetrable academic jargon, but at its core, it is simply the mathematics of composition. In functional programming, we use its concepts to build modular, predictable, and bug-resistant code.
JavaScript isn't a pure functional language like Haskell, but it has first-class functions and treats functions as values. This makes it entirely possible to implement category theory primitives.
Here is how the theoretical concepts map to practical JavaScript.
The Vocabulary of Category Theory
Before jumping into code, let's define the fundamental pieces:
