typelevel/cats-effect

The pure asynchronous runtime for Scala

softwaremill/magnolia

Easy, fast, transparent generic derivation of typeclass instances

tofu-tf/tofu

Functional programming toolbox

typelevel/cats-mtl

cats transformer type classes.

djspiewak/shims

Seamless interop layer between cats and scalaz

softwaremill/scala-common

Tiny independent libraries with a single purpose, often a single class

scalaz/scalaz-deriving

Principled, fast, typeclass derivation.

hablapps/puretest

Purely functional testing in Scala

dmytromitin/auxify

Introduces macro/meta annotations @ aux, @ self, @ instance, @ apply, @ delegated, @ syntax and String-based type class LabelledGeneric

evolution-gaming/derivation

Configured derivation library for scala 3

xuwei-k/play2scalaz

Scalaz typeclasses <~> Playframework2 typeclasses

nrktkt/ninny-json

JSON typeclasses that know the difference between null and absent fields

mlopes/wen

Date and time types and instances

fdietze/formidable

Automatic Form Derivation for Outwatch

dmytromitin/shapeless-circe-patched-type-keytag

https://stackoverflow.com/questions/74384745/encoding-decoding-a-field-with-any-datatype-assigned-with-value-none-in-scala

sweet-delights/delightful-typeclasses

A Scala library containing utility typeclasses

dmytromitin/shapeless

Generic programming for Scala