Cats Effect manages effects using an IO monad. Most of the projects I currently work with use it. This is why I say it's not useful to try to draw a strict lin

Cats Effect manages effects using an IO monad. Most of the projects I currently work with use it. This is why I say it's not useful to try to draw a strict line. I'm not going to argue with you on whether using an IO monad in an impure language is "pure FP" or not, but some Scala devs would. That argument in itself is not nearly as illuminating as knowing all the tools and concepts.