Provides immutable datatypes for working with bits and bytes
Powerful new number types and numeric abstractions for Scala.
First class syntax support for type classes in Scala
Implementation of the `java.time` API in scala. Especially useful for scala.js
Easy, fast, transparent generic derivation of typeclass instances
Configurable generic derivation for Circe
Scala library providing "source" metadata to your program, similar to Python's __name__, C++'s __LINE__ or Ruby's __FILE__.
ScalaTags is a small XML/HTML construction library for Scala.
Generation of arbitrary case classes / ADTs instances with scalacheck and shapeless
Wonderful reusable code from Twitter
Scala combinator library for working with binary data
ScalaTest + Play
Flexible law checking for Scala
(No longer actively maintained.)
Functional JDBC layer for Scala.
Parallel collections standard library module for Scala 2.13+
Facebook's React on Scala.JS
Jawn is for parsing jay-sawn (JSON)
Scala compiler plugin for static code analysis