@ITOWFYL There is a nice example of Quicksort in the deck posted here: From Subtype Polymorphism To Typeclass-based Ad hoc Polymorphism - An Example.
That deck goes over and above what you’re asking about, but the starting example is worth a look, and the subject of that deck is worth revisiting once you’ve become more comfortable with Scala.
I would imagine that having a look round FPIlluminated might be useful anyway…