http://kategory.io/

KΛTEGORY is a library that started as a port of Typelevel Scala cats for the Kotlin Programming Language and is now evolving to bring the best of typed FP to Kotlin. This talk covers some of the main data types and abstractions that make typed Functional Programming in Kotlin Possible. Kategory features techniques such as monadic comprehensions, laws, applicative builders, emulated higher kinds, free monads, and global typeclass instances for the increasingly popular Kotlin programming language. We discuss some pragmatic applications of KΛTEGORY and some of the different styles you can adopt when working with typed FP in Kotlin alogn with a proposal to introduce type classes and higher kinds as part of the language.

https://github.com/47deg/kategory-intro