I would add only one thing to the article. Algebraic data types are so great because they are so dumb. ADTs are inherently stateless, for example (as long as yo

I would add only one thing to the article. Algebraic data types are so great because they are so dumb. ADTs are inherently stateless, for example (as long as you don't put stateful things inside them). This makes them extremely easy to reason about: they're no harder to reason about than an integer is.