A case for effect systems Daniel Spiewak's 2022 Scala Love keynote. "The" case, but let's dial it back.
Notes: 'Your Search Service as a Composable Function' From former Etsian Stefanie Schirmer in 2018 on designing Etsy's search platform using Finatra and functional programming principles.
Intro to Cats Effect Notes on Adam Rosein's presentation to Skills Matter from 04/2021 in partnership with 47D
Notes: 'Programming Scala' These are from a textbook written in 2009! But noting things that should still be relevant in 2021.