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New Arrow website launches

New Arrow website launches

We’re excited to announce the launch of the new website for the Arrow family of libraries designed for functional programming in Kotlin. The launch of this website signifies not only the massive growth of this set of open source tools in 2019 but the projected expansion planned for 2020 and beyond.

A New UI

The site has been completely revamped with a sleek new UI. The minimalist design provides a clean layout, creating improved organization overall. This includes better organization of Arrow documentation, which is now just a click away in the sidebar.

Module Division

Arrow is currently divided into four components, but as we make more features available in the future, additional modules will be added. This is something we’re looking for the community’s help with! If you have ideas that you believe would improve Arrow’s mission and would be a good fit, please join us.

For now, the website clearly identifies Arrow’s available modules, making it easier than ever to quickly access information about each of the following:

Arrow Core - Arrow is the functional companion to Kotlin’s Standard Library.

Arrow Core

Arrow FX - Arrow FX is a next-generation Typed FP Effects Library built to tame side effectful APIs.

Arrow Fx

Arrow Optics - Arrow Optics helps by transforming and computing over immutable data models in Kotlin.

Arrow Optics

Arrow Meta - Arrow Meta is the functional companion to the Kotlin Compiler and its plugin ecosystem.

Arrow Meta

Also included is the new Arrow Incubator featuring libraries currently in initial development or brainstorming phases. These projects will be promoted to top level libraries as they become ergonomic, stable, and follow the standards of quality we expect under the Arrow umbrella.

Arrow Incubator

New Arrow media section

A new media section has been added to the site, showcasing tutorials, conference presentations, and other Arrow-related content. We’re still in the process of uploading materials to this section, but there’s plenty of content for you to get started with.

Have a talk, training video, blog post, or related materials to add? Don’t hesitate to open a PR!

Arrow Media Section

Special thanks for this undertaking goes to Antonio Mateo, Juan Valencia, Israel Perez, Francisco Díaz, Jetro Cabau, and Jason McClellan.

For a full list of the contributors who have helped Arrow get to where it is today, please check out: Arrow Contributors. We’re always looking for additional help, please view the guidelines for contributing and take a look at the help-wanted issues. All levels are welcome and we offer 1:1 mentoring through Arrow’s Slack and Gitter channels.

If you would like to support Arrow, but don’t have the time to invest in contributing, consider picking up some Arrow swag! All proceeds are invested back into advancing the library.


The active development of Arrow is proudly sponsored by 47 Degrees, a Functional Programming consultancy with a focus on the Scala, Kotlin, Haskell, and Swift programming languages.

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