It's hard coming back down to the earth of a JVM based language after spending time with Haskell and OCaml. The type systems are enviable, and the abstractions available are incredibly powerful.

Yallop and White's paper on Lightweight Higher-Kinded Polymorphism has been an inspiration for many libraries seeking to add functional abstractions to languages that don't support them. For Kotlin, one library is [Arrow](arrow-kt.io), which provides incredibly powerful abstractions over native language capabilities like co-routines, reactive-streams and nullable types.

This talk will discuss functional programming in Kotlin with the Arrow library, how the abstractions it provides can improve your code, and how this magic that provides higher-kinded types works under the hood.