Installation 

Start here to connect a StyleX build to TYPO3. The connector resolves class names from a JSON manifest; it does not compile StyleX or deliver CSS. A working site therefore needs the extension, a frontend build, manifest registration, and an asset include in the rendered page.

This guide uses a Composer-based TYPO3 project and a sitepackage named my_sitepackage under packages/my_sitepackage. Run commands from the project root and substitute your own package name and paths. The extension targets TYPO3 12.4, 13.4, and 14.3 or later in the 14.x line. TYPO3 12.4 supports PHP 8.1 through 8.4; TYPO3 13.4 and 14.3 require PHP 8.2 or later. This extension currently limits its PHP support to 8.4. You also need a Node.js version supported by your Vite release.

TYPO3 12.4 is in ELTS. Use a current patched ELTS core release in production.

Follow these pages in order:

If the project already has Vite, keep its package manager, lockfile, plugins, and entrypoint. Add the StyleX and manifest steps in Vite and asset delivery to that build. For a new DDEV project, read DDEV development server after installing the dependencies, then return to the Vite guide. DDEV changes how the development server runs; it does not change the manifest or TYPO3 configuration.

After verification, see Using the ViewHelper for class composition. For Content Blocks, Fluid Styled Content, or Bootstrap, choose the relevant guide under Integrations after the base installation works.