cats

## Cats

![Cats graphic](https://typelevel.org/cats/img/cats2.png)

[![cats-core Scala version support](https://index.scala-lang.org/typelevel/cats/cats-core/latest-by-scala-version.svg?targetType=Js)](https://index.scala-lang.org/typelevel/cats/cats-core) ![Continuous Integration](https://github.com/typelevel/cats/workflows/Continuous%20Integration/badge.svg)
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[![Discord](https://img.shields.io/discord/632277896739946517.svg?label=&logo=discord&logoColor=ffffff&color=404244&labelColor=6A7EC2)](https://discord.gg/XF3CXcMzqD)

### Overview

Cats is a library which provides abstractions for functional programming in the [Scala programming language](https://scala-lang.org).

Scala supports both object-oriented and functional programming, and this is reflected in the hybrid approach of the
standard library. Cats strives to provide functional programming abstractions that are core, [binary compatible](#binary-compatibility-and-versioning), [modular](https://typelevel.org/cats/motivations.html#modularity), [approachable](https://typelevel.org/cats/motivations.html#approachability) and [efficient](https://typelevel.org/cats/motivations.html#efficiency). A broader goal of Cats is to provide a foundation for an [ecosystem of pure, typeful libraries](https://typelevel.org/cats/typelevelEcosystem.html) to support functional programming in Scala applications.

For more detail about Cats' motivations, go [here](https://typelevel.org/cats/motivations.html).

### Why "cats"?

The name is a playful shortening of the word *category*, from "[category theory](https://en.wikipedia.org/wiki/Category_theory)".

Regardless, you do not need to know anything about category theory to use Cats.

## Contributors

### Code Contributors

This project exists thanks to [all the people who contribute](https://github.com/typelevel/cats/graphs/contributors). We welcome contributions to Cats and would love for you to help build
Cats. See our [contributor guide](CONTRIBUTING.md) for more
information about how you can get involved as a developer. If you are looking for something to start with, [here is a beginner friendly list](https://github.com/typelevel/cats/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22).

### Financial Contributors

[Become a financial contributor](https://opencollective.com/typelevel) and help us sustain our community. Donations directly support office hours for maintainers, better documentation and strategic initiatives.

<h4>Platinum Sponsors</h4>
<a href="https://opencollective.com/typelevel/contribute/platinum-sposor-12420/checkout">Platinum sponsorship</a> starts at $950 USD/month.
<div id="platinum-sponsors">
  <noscript>Platinum Sponsors appear here at <a href="https://typelevel.org/cats/#financial-contributors">https://typelevel.org/cats</a></noscript>
</div>

<h4>Gold Sponsors