Project Index

Automatic derivation for argonaut

RDF, SPARQL and Linked Data technologies

Pure, reactive UI library for building web applications with Cats Effect + FS2

An Actor Model implementation built on top of Cats-Effect, providing a higher-level abstraction for managing concurrency.

A case-insensitive string for Scala

A thin wrapper for the Launch Darkly Java server SDK using cats-effect and fs2

Cats instances for various Twitter Open Source Scala projects

A library intended to provide abstractions for functional programming in Scala, leveraging its unique features. Design goals are approachability, modularity, documentation and efficiency.

Data structures that facilitate pure functional programming with cats

The IO Monad for Scala, plus type classes for general effect types.

Monad transformers made easy

A parsing library for the cats ecosystem

Scalatest bindings for Cats.

A STM implementation for Cats Effect

A library of utilities for tagless final algebras

Instances for Cats Typeclasses for Java 8 Time

Yet another JSON library for Scala

Functional Configurations for Scala

A statically typed unit analysis library for Scala

Cross-platform CRON expression parsing for Scala

A composable command-line parser for Scala.

Originally intended for internal use in spire, this library helps libraries declaring type classes to precisely state the laws which instances need to satisfy, and takes care of not checking derived laws multiple times.

A pure functional JDBC layer for Scala. It is not an ORM, nor is it a relational algebra; it just provides a principled way to construct programs (and higher-level libraries) that use JDBC.

Event-driven automata for Scala, Scala.js and scala native. This library provides purely functional state machines that can be used to create event sourced and/or CQRS style applications. It also includes production ready backends.

Extensible effects are an alternative to monad transformers for computing with effects in a functional way. This library is based on the “free-er” monad and an “open union” of effects described by Oleg Kiselyov in “Freer monads, more extensible effects”

Sharded and event-sourced entities using tagless-final algebras

Populate case classes from any configuration source

Object-Notation Abstraction for JSON, binary, HOCON, etc.

Feral cats are homeless, feral functions are serverless

A purely functional web frontend framework for Scala.js.

Library built on top of Cats that provides efficient data access from heterogeneous dataurces

Purely functional basic blocks atop of Finagle for building composable HTTP APIs

Frameless is a library for working with Spark using more expressive types.

Micro library providing AES encryption/decryption of fs2.Stream[F, Byte].

Compression Algorithms for Fs2

Parse and transform data (CBOR, CSV, JSON, XML) in a streaming manner

Idiomatic Cats Effect + FS2 integrations for Web APIs

gRPC implementation for FS2/cats-effect

FS2 is a library for purely functional, effectful, and polymorphic stream processing library in the Scala programming language. Its design goals are compositionality, expressiveness, resource safety, and speed. The name is a modified acronym for Functional Streams for Scala (FSS, or FS2).

Functional GraphQL server for the Typelevel stack

Purely functional HTTP client

A typeful, purely functional HTTP library for client and server applications

Summoning implicit values

Integration of jawn and fs2 for streaming, incremental JSON parsing

A Keyed Pool Implementation for Scala

Plugin for nicer type-lambda syntax

Automatic type class derivation

Site and e-book generator and customizable text markup transformer for sbt, Scala and Scala.js

Pure functional JDBC layer with Cats Effect 3 and Scala 3

Purely functional, non-blocking RabbitMQ client for scala, scala js and scala native built on top of fs2.

Compile time dimensional analysis for any problem domain

Compile time validation of literal values built from strings

Logging Tools For Interaction with cats-effect

High-performance library for composing asynchronous, event-based programs, exposing a Reactive Streams implementation along with primitives for dealing with concurrency and side-effects.

Optics library offering a simple yet powerful API to access and transform immutable data

Enrichments to standard library classes to ease functional programming

functional tracing for cats

An OpenTelemetry library based on cats-effect

The Functional and Reactive Web-Frontend Library for Scala.js

The parsley-cats library exposes Cats instances for Parsley parsing library.

An actor library for Cats Effect

Provides tools for generic programming, and typeclasses for monad transformers and higher kinded data.

A boilerplate-free library for loading configuration files

Tools for refining types with type-level predicates which constrain the set of values described by the refined type, for example restricting to positive or negative numbers.

ScalaCheck is a library for automated property-based testing. It contains generators for randomized test data and combinators for properties.

Automatic derivation for ScalaCheck

Platform and framework for Scala devs to learn about Scala libraries

A robot that helps keeping Scala projects up-to-date

scodec is a combinator library for working with binary data. It focuses on contract-first and pure functional encoding and decoding of binary data and provides integration with shapeless.

Code coverage tool for Scala

Shapeless is a generic programming library. Starting with implementations of Scrap your boilerplate and higher rank polymorphism in Scala, it quickly grew to provide advanced abstract tools like heterogenous lists and automatic instance derivation for type classes.

First-class syntax for type classes

Simulacrum as Scalafix rules

Operations for primitive and String singleton types

A data access library for Scala + Postgres

Property-based testing with integrated shrinking

specs2 is a library for writing executable software specifications, aiming for conciseness, readability and extensibility.

Spire is a numeric library for Scala which is intended to be generic, fast, and precise. Using features such as specialization, macros, type classes, and implicits, Spire works hard to defy conventional wisdom around performance and precision trade-offs.

The Scala API for Quantities, Units of Measure and Dimensional Analysis

Micro-library for building effectful protocols

A compiler plugin adding support for mutual tail recursion

A Giter8 template for sbt-typelevel

Development tools for Typelevel projects

Functional user journeys

A purely functional, interval based rate limiter

Type-safe, persistent storage for values of arbitrary types