FOSSBilling builds shared browser assets from frontend/ and theme assets from each theme workspace.

• npm run build checks frontend source, builds core assets, and builds all themes.
• npm run build:production runs the same build with NODE_ENV=production.
• npm run check runs lightweight JavaScript syntax checks and validates theme icon manifests.
• npm run build-admin_default and npm run build-huraga build a single theme.

Generated assets are written to src/public/assets and src/themes/*/assets/build. These paths are ignored by Git and are copied into release artifacts by the Docker build.

Themes own the UI packages they consume. Shared tooling in frontend/tools can help compile assets, generate sprites, and post-process CSS, but it should not make a theme depend on a specific UI package.

Examples:

• admin_default owns Tabler, Coloris, Chart.js, Litepicker, Tom Select, Flag Icons, and its Tabler icon package.
• huraga owns Bootstrap, Tom Select, Flag Icons, and its Tabler icon package.
• svg-sprite is a root development dependency because the shared sprite helper imports it.

Theme icon sprites are generated from each theme's icon-manifest.json.

• Add static SVG icon usage to the relevant theme manifest.
• Mark icons as "dynamic": true when the icon name is resolved at runtime, such as admin navigation icons from module metadata.
• Put theme-specific SVG files in the theme's custom-icons directory.
• Reference generated symbols with inline sprite IDs, for example <use href="#home" />.

Run npm run check-icons before changing icon usage.

Theme vendor CSS belongs in src/themes/*/assets/css/vendor.css. Theme-specific styles belong in the theme Sass entrypoint.

PurgeCSS runs only for production builds. A PurgeCSS failure fails production builds so release CSS problems are caught early.