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+---
+title: "CSS-in-JS"
+ring: adopt
+quadrant: methods-and-patterns
+tags:       [coding, frontend]
+---
+
+Since the arrival of react 18, many CSS-in-JS libraries like styled components, emotion and stitches face a big problem.
+They generate CSS only at runtime and therefore incompatible with streaming and React Server Components.
+The React developers have written an [article](https://github.com/reactwg/react-18/discussions/110) about this, in which they explicitly advise against CSS-in-JS libraries that generate CSS at runtime.
+
+This has led to great uncertainty among developers and communities of the affected libraries.
+Is refactoring possible to turn the runtime libraries into buildtime libraries?
+So far, none of the libraries have announced anything in this direction and one of the most popular new libraries, stitches, has been [no longer maintained](https://github.com/stitchesjs/stitches/discussions/1149#discussioncomment-6223090).
+
+Fortunately, more and more CSS-in-JS solutions that generate CSS at buildtime are emerging since then.
+Libraries like [Vanilla Extract](https://vanilla-extract.style/), [panda](https://panda-css.com/) or [Kuma UI](https://www.kuma-ui.com/) keep the excellent developer experience, compensate the performance disadvantages and are compatible to React 18.
+
+Unfortunately, these libraries are not yet very widespread and it is difficult to judge how they will develop.
+Therefore, at AOE we continue to use the established solutions as long as the new React features are not mandatory.
+
+In addition, we are gaining experience with the new libraries because we see a lot of potential.