Here are my notes from the book Essential Effects . I really love this book as it explained a lot of concepts that are used in functional programming and the cats effect ecosystem. I love how the examples were concise and practical.

Before we start talking about monad transformers, let’s talk about why we may need them. Let’s say we define the following classes and functions in this contrived example:

P.S This post is for beginners, experienced developers can skip this :)

P.S. If you are a newbie, I highly encourage you to read part 1 of this post.

This post assumes a basic knowledge of Scala and SBT set up

This post is going to try to simplify the concepts of monads, this means that a lot of technicalities may be omitted, but I’ll be sure to attach links to more technical concepts in this post.