A Toolkit for Zero-Runtime CSS-in-JS Libraries


wyw-in-js, short for "Whatever-you-want-in-JS," is the world's first toolkit for creating various zero-runtime CSS(and more)-in-JS libraries. In essence, it empowers developers to build their own solutions with arbitrary syntax and functionality, offering complete independence from specific implementations.


This library evolved from the CSS-in-JS library Linaria (opens in a new tab), with the aim of decoupling from a specific implementation and providing developers with a comprehensive toolkit for crafting their own solutions with custom syntax and features.

Key Features

  • Provides an API for creating custom processors (e.g., css and styled in Linaria (opens in a new tab) or makeStyles in Griffel (opens in a new tab)).
  • Supports a wide range of syntaxes, including tagged templates, function calls, and object literals.
  • Computes any unprepared JavaScript during the build phase, generating a set of artifacts that processors can transform into styles (or other outputs, depending on the processor).
  • Allows for arbitrary JavaScript in style definitions, including imports, conditionals, and loops.
  • Offers loaders and plugins for popular bundlers (including Webpack, Vite, esbuild) and frameworks (Next.js), ensuring compatibility with various build systems.