0.4.1 is now the stable release for that work. The latest tag moves to 0.4, while 0.3.8 remains available by exact version for teams that need a staged migration.

A compiler contract developers can rely on​

Static declarations belong in StyleSheet.create(). Values that depend on props or themes should remain small runtime expressions. The 0.4 compiler makes that boundary explicit for styled components and function-scoped css templates.

Strict mode turns that contract into a CI check:

['babel-plugin-kstyled', { strict: true }];

When a matched template cannot be transformed, the build fails with compiler context instead of quietly changing its performance characteristics.

Composition without wrapper debt​

Real component libraries extend styles, add attrs, forward refs, switch the render target with as, and pass external styles. The beta preserves those behaviors while collapsing nested styled wrappers back to the original target.

The runtime also avoids avoidable allocation in common paths: a single compiled style remains a single reference, normalized dynamic objects are reused, and external styles are not cloned when no shorthand expansion is needed.

Better boundaries for library authors​

defineTheme and generic useTheme improve theme inference without requiring global type augmentation. Explicit CJS, ESM, and React Native export conditions make package resolution less dependent on bundler heuristics. Source maps and matching declarations ship with both the runtime and compiler packages.

These are not headline APIs, but they are the details that determine whether a styling package behaves consistently in an application, a component library, and a test runner.

Upgrade to 0.4​

Install both packages at the same version:

pnpm add kstyled@0.4.1
pnpm add -D babel-plugin-kstyled@0.4.1

Then validate production builds and representative screens on iOS, Android, and web. The full release notes include migration guidance and a practical validation checklist.