npm package: @stylexjs/postcss-plugin
Description: PostCSS plugin for StyleX
Latest version: 0.18.2

# @stylexjs/postcss-plugin

## Documentation Website

[https://stylexjs.com](https://stylexjs.com)

## Installation

Install the package by using:

```bash
npm install --save-dev @stylexjs/postcss-plugin autoprefixer
```

or with yarn:

```
yarn add --dev @stylexjs/postcss-plugin autoprefixer
```

Add the following to your `postcss.config.js`

```javascript
// postcss.config.js
module.exports = {
  plugins: {
    '@stylexjs/postcss-plugin': {
      include: ['src/**/*.{js,jsx,ts,tsx}'],
    },
    autoprefixer: {},
  },
};
```

Add the following to your `babel.config.js`

```javascript
import styleXPlugin from '@stylexjs/babel-plugin';

const config = {
  plugins: [
    [
      styleXPlugin,
      {
        // Required for this plugin
        runtimeInjection: false,
        dev: true,
        // Set this to true for snapshot testing
        // default: false
        test: false,
        // Required for CSS variable support
        unstable_moduleResolution: {
          // type: 'commonJS' | 'haste'
          // default: 'commonJS'
          type: 'commonJS',
          // The absolute path to the root directory of your project
          rootDir: __dirname,
        },
      },
    ],
  ],
};

export default config;
```

Add the following to `src/stylex.css`

```css
/**
 * The @stylex directive is used by the @stylexjs/postcss-plugin.
 * It is automatically replaced with generated CSS during builds.
 */
@stylex;
```

Then, import this file from your application entrypoint:

```javascript
// src/index.js
import './stylex.css';
```

## Plugin Options

### include

```js
include: string[] // Default: auto-discovered
```

Array of paths or glob patterns to compile.

When omitted, the plugin auto-discovers source files in the project `cwd` and
direct dependencies that use StyleX.

---

### exclude

```js
exclude: string[] // Default: []
```

Array of paths or glob patterns to exclude from compilation. Paths in exclude
take precedence over include.

When `include` is omitted, the plugin automatically excludes common build and
dependency folders (for example `node_modules`, `.next`, `dist`, `build`) to
keep discovery focused on source files.

---

### cwd

```js
cwd: string; // Default: process.cwd()
```

Working directory for the plugin; defaults to process.cwd(). Dependency paths
and Babel config resolution use this value.

---

### babelConfig

```js
babelConfig: object; // Default: {}
```

Options for Babel configuration. By default, the plugin reads from
babel.config.js in your project. For custom configurations, set babelrc: false
and specify desired options. Refer to
[Babel Config Options](https://babeljs.io/docs/options) for available options.

---

### useCSSLayers

```js
useCSSLayers: boolean; // Default: false
```

Enabling this option switches Stylex from using `:not(#\#)` to using `@layers`
for handling CSS specificity.

---

### importSources

```js
importSources: Array<string | { from: string, as: string }>; // Default: ['@stylexjs/stylex', 'stylex']
```

Possible strings where you can import stylex from. Files that do not match the
import sources may be skipped from being processed to speed up compilation.

When omitted, the plugin will infer `importSources` from your
`@stylexjs/babel-plugin` options (if present) and still include the default
StyleX sources.

---

## Debugging auto-discovery

Set `STYLEX_POSTCSS_DEBUG=1` to print resolved plugin inputs, including:
- resolved `importSources` and where they came from
- final `include` and `exclude` globs
- discovered dependency directories