cssnano is a production-grade CSS minifier built as a modular PostCSS plugin system. It takes CSS input and applies a configurable chain of optimizations—color reduction, value normalization, selector minification, longhand merging, rule merging, whitespace stripping, duplicate removal, and more—to produce the smallest possible CSS output while preserving semantics and browser compatibility. The architecture is a monorepo of over 30 PostCSS plugins, orchestrated by three built-in presets (lite, default, advanced) that balance aggressiveness against safety. The codebase is exceptionally well-engineered: every optimization is driven by data extracted from CSS specifications (via @webref/css) and browser compatibility data (via @mdn/browser-compat-data), ensuring transformations only apply when safe for target browsers. Extensive testing includes unit tests, integration tests against major CSS frameworks, fuzz testing with invariants (idempotency, cascade preservation), mutation testing, and statistical performance benchmarking. The project demonstrates exceptional craftsmanship in its handling of CSS value grammars, cascade-aware merging algorithms, and browser-specific fallbacks.
This repository is a React component library (`@codegouvfr/react-dsfr`) that provides a complete implementation of the French government's Design System (DSFR) for modern web applications. It covers nearly all DSFR UI components (buttons, forms, navigation, modals, tables, etc.) and adds framework-specific integrations for Next.js (both Pages Router and App Router), Vite, and Create React App, including SSR support without flash. The library also ships a CLI tool (`npx react-dsfr`) that performs static analysis of a project's source code to generate an optimized CSS bundle containing only the DSFR components actually used, solving a common bloat problem in design-system integrations. Additionally, it provides a GDPR consent management system, i18n per component, MUI theming compatibility, dark mode, and a large set of SVG pictograms. The architecture is a typical React library: each component is a memoized, forwardRef-wrapped functional component using DSFR CSS classes via a `cx` helper. Build-time scripts parse the DSFR CSS into TypeScript constants (spacing, colors, breakpoints, class names) to ensure type safety and ease of use. The library avoids bundling all DSFR CSS in JavaScript; instead, it relies on the CSS being loaded from `node_modules` and optionally trimmed by the CLI. Notable internal patterns include a lightweight `StatefulObservable` for reactive state, a set of stable-callback hooks (`useConst`, `useConstCallback`) to avoid unnecessary re-renders, and a factory pattern for pictograms. While not a hybrid repo, its build pipeline demonstrates a unique approach to CSS-to-TypeScript code generation. The codebase is actively maintained with a comprehensive test suite covering both runtime behavior and build-script correctness. However, it carries some technical drift: it relies on a patched version of `@gouvfr/dsfr` (1.14.2), the pictograms are large inline SVGs that must be manually updated, and the CSS optimization script uses hardcoded component mappings that could diverge from future DSFR releases. Overall, it is a high-quality, production-grade library suitable for any French public service website built with React.
nuxt-purgecss is a Nuxt 3 module that integrates PurgeCSS to remove unused CSS from the final build. It hooks into Nuxt's PostCSS configuration to add the `@fullhuman/postcss-purgecss` plugin with sensible defaults tailored for Vue and Nuxt projects. The module automatically scans common Nuxt directories (components, layouts, pages, composables, app files, plugins, and nuxt.config) for used CSS classes, and includes a safelist of typical Nuxt classes (e.g., transition classes, nuxt-link classes, scoped style attributes) to prevent accidental removal. It also provides a custom default extractor that strips inline `<style>` blocks from Vue Single File Components before extraction, ensuring that only classes used in templates are considered. The module is disabled by default in development mode and can be configured via the `purgecss` key in `nuxt.config`. The codebase is small, well-structured, and includes integration tests using `@nuxt/test-utils` that verify correct purging behavior on a playground Nuxt project. However, the project has seen no releases since September 2022 and relies on outdated dependencies (e.g., Nuxt 3 RC, Node 16 in CI), indicating it is no longer actively maintained.