▲ + 💅 Better CSS Support for NextJS

Feature-parity with NextJS's built-in CSS with the flexibility to support your favorite pre-processor(s)!

This is a NextJS configuration decorator with the goal of approximately mirroring NextJS's built-in CSS support without losing the flexibility of technology choice. For example, at Magic Labs, we are invested in LESS! However, the built-in CSS features of NextJS are very desirable, so we created @magiclabs/next-css to bridge the gap.

🔗 Installation

@magiclabs/next-css is available as an NPM package:

# Via NPM:
npm install --save @magiclabs/next-css

# Via Yarn:
yarn add @magiclabs/next-css

Peer Dependencies

This module requires NextJS (^12.0.0) as a peer dependency. Additionally, any Webpack dependencies related to your CSS pre-processor of choice are required to be installed separately.

📚 Usage

The stylesheet is compiled to .next/static/css. Next.js will automatically add the css file to the HTML. In production, a chunk hash is added so that styles are updated when a new version of the stylesheet is deployed.

Basic Configuration

Create a next.config.js in the root of your project (next to pages/ and package.json).

// next.config.js
const { withCSS } = require('@magiclabs/next-css'); // Please note the named export!

module.exports = withCSS({
  // Array of objects configuring any CSS pre-processors you like!
  preProcessors: [
    {
      extensions: [...], // i.e.: ["less"] or ["sass", "scss"]
      use: [...], // Receives same configuration as Webpack > Module > Rule > Use
    },
  ],

  // Also valid as a factory function!
  // Receives the same arguments as a NextJS custom `webpack` function.
  preProcessors: (config, options) => [...],
});

Configuration Fields

• preProcessors: An array of PreProcessorItem objects, or a function returning an array of PreProcessorItem objects with the following shape:
  • extensions: An array of String values representing CSS file extensions (i.e.: "css", "less", "scss").
  • use: An array of objects compatible with Webpack's Module Rules#UseEntry schema.

⚡️ Quick Starts

You can easily configure @magiclabs/next-css for the following common use-cases:

• LESS

With LESS

First, install your LESS-specific dependencies:

# Via NPM:
npm install --save less less-loader

# Via Yarn:
yarn add less less-loader

Next, configure the pre-processor with @magiclabs/next-css:

// next.config.js
const { withCSS } = require('@magiclabs/next-css');

module.exports = withCSS({
  preProcessors: [
    {
      extensions: ["less"],
      use: [require.resolve('less-loader')],
    },
  ],
});

⚖️ Trade-offs

• More dependencies leads to longer NPM package installation times. These are marginal for a typical project.

• This is a wholesale re-implementation of NextJS CSS support, so there may be some inconsistencies between the end results. NextJS notably benefits from aggressive internal optimizations which may be missing or unaccounted for here. That being said, we try our best to match the internal implementation as closely as possible.