Facebook's React on Scala.JS
The IO monad for cats
Random Data Generation and/or Property Testing in Scala & Scala.JS.
Expressive types for Spark.
Asynchronous, Reactive Programming for Scala and Scala.js.
Reasonable telnet server for Scala.
A DSL for BDD, leveraging Functional Programming techniques.
Generic programming for Scala
principled database access for scala
A tiny and principled library for type-safe IDs
Compositional, streaming I/O library for Scala