Style once, use everywhere.
Style Dictionary is a build system that allows you to define styles once, in a way for any platform or language to consume. A single place to create and edit your styles, and a single command exports these rules to all the places you need them - iOS, Android, CSS, JS, HTML, sketch files, style documentation, or anything you can think of. It is available as a CLI through npm, but can also be used like any normal node module if you want to extend its functionality.