# moox/postcss-cssnext

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5,261 stars · 185 forks · JavaScript · MIT · archived

## Links

- GitHub: https://github.com/MoOx/postcss-cssnext
- Homepage: https://moox.io/blog/deprecating-cssnext/
- awesome-repositories: https://awesome-repositories.com/repository/moox-postcss-cssnext.md

## Topics

`css` `cssnext` `javascript` `postcss` `postcss-plugins`

## Description

postcss-cssnext is a PostCSS plugin suite and transpiler designed to convert modern CSS features and emerging syntax into code compatible with older web browsers. It functions as a polyfill engine that adds fallback properties and replaces modern units to ensure consistent rendering across different browser environments.

The tool automates the conversion of advanced CSS specifications into standard styles by employing a transformation engine for emerging features such as nesting and advanced selectors. It also includes a utility for converting relative rem units into pixel values based on defined root font sizes.

The project integrates into development pipelines through a command line interface that supports file watching and target browser configuration. These workflows use a browser compatibility list to determine which transformations are necessary for the specified targets.

## Tags

### Web Development

- [CSS Transpilers](https://awesome-repositories.com/f/web-development/web-infrastructure-deployment/asset-management-build-tools/asset-lifecycle-orchestration/asset-processing/css-transpilers.md) — Functions as a CSS transpiler that converts emerging features like nesting into browser-compatible syntax. ([source](https://github.com/MoOx/postcss-cssnext/blob/master/CHANGELOG.md))
- [CSS Property Polyfills](https://awesome-repositories.com/f/web-development/css-property-polyfills.md) — Creates fallback properties for modern CSS features to ensure consistent rendering across browser environments. ([source](https://github.com/MoOx/postcss-cssnext/blob/master/CHANGELOG.md))
- [CSS Syntax Transpilation](https://awesome-repositories.com/f/web-development/css-syntax-transpilation.md) — Transpiles modern CSS syntax into legacy formats based on browser compatibility lists.
- [PostCSS Plugin Suites](https://awesome-repositories.com/f/web-development/postcss-plugin-suites.md) — Provides a comprehensive suite of plugins to automate the conversion of modern CSS into standard styles.
- [CSS Build Tools](https://awesome-repositories.com/f/web-development/web-infrastructure-deployment/asset-management-build-tools/style-optimization-tools/css-build-tools.md) — Provides a build-time engine to automate CSS transformations and browser target configurations.
- [PostCSS Pipeline Integration](https://awesome-repositories.com/f/web-development/postcss-pipeline-integration.md) — Integrates with the PostCSS engine to handle CSS tokenization and source map generation.

### Part of an Awesome List

- [CSS Polyfills](https://awesome-repositories.com/f/awesome-lists/devtools/css-polyfills.md) — Implements CSS polyfills by adding fallback styles for consistent cross-browser rendering.
- [CSS Polyfill Engines](https://awesome-repositories.com/f/awesome-lists/devtools/css-polyfills/css-polyfill-engines.md) — Acts as a polyfill engine that replaces modern units and adds fallback properties for consistency.

### Data & Databases

- [Style](https://awesome-repositories.com/f/data-databases/data-transformation-functions/transformation-chains/style.md) — Processes styles through a sequence of modular plugin functions to apply transformations and polyfills.

### Development Tools & Productivity

- [AST-Based Source Transformations](https://awesome-repositories.com/f/development-tools-productivity/ast-transformation-tools/ast-to-source-conversion/ast-based-source-transformations.md) — Implements AST-based transformations to modify CSS syntax trees before generating final stylesheets.
- [CSS Build Process Configurations](https://awesome-repositories.com/f/development-tools-productivity/build-plugin-architectures/build-configuration-architectures/build-process-hooks/css-build-process-configurations.md) — Provides a CLI to control the transformation process, including target browser lists and file watching. ([source](https://github.com/MoOx/postcss-cssnext/blob/master/CHANGELOG.md))

### User Interface & Experience

- [CSS Unit Converters](https://awesome-repositories.com/f/user-interface-experience/css-unit-converters.md) — Includes a utility to convert relative rem units into pixel values based on root font sizes. ([source](https://github.com/MoOx/postcss-cssnext/blob/master/CHANGELOG.md))