Calico is a UI library for the Typelevel.js ecosystem. It leverages the abstractions provided by Cats Effect and FS2 to provide a fluent DSL for building web applications that are composable, reactive, and safe. If you enjoy working with Cats Effect and FS2 then I hope that you will like Calico as well.


Calico was inspired by Laminar. I have yet only had time to plagiarize the DSL and a few of the examples ;) Thanks to @raquo for sharing their wisdom.

I am very grateful to @SystemFw who gave me a tutorial on all things Functional Reactive Programming shortly before I embarked on this project.

Try it!

With special thanks to @yurique, you can now try Calico right in your browser at!

libraryDependencies += "com.armanbilge" %%% "calico" % "0.2.2"

Please open issues (and PRs!) for anything and everything :)