Haskell doesn't force you to make the separation either (nor does it trivialize software design). You can write all your pure code in IO if that is what you'd

Haskell doesn't force you to make the separation either (nor does it trivialize software design). You can write all your pure code in IO if that is what you'd prefer. I look at types as more of a way to communicate to others using my code as "here be dragons, this has side effects" or vice versa. The developer using your code doesn't just have to trust a comment block, they can see it directly in the types. I agree monad composition isn't amazing. When I was writing a lot of Haskell (I was working on real time 3d reconstruction algorithms from video feeds using camera input and OpenGL output) it wasn't a very large roadblock though. But effect type systems seemed like they might be cleaner. I don't have time to read through that article right away but I saved it for future reference - thank you for sharing.