Razzle: CSS Modules with SCSS files

@dizzyn The razzle plugin above I think is just for straightforward SCSS support.

I lifted this from elsewhere, but works for me. Essentially you copy the existing CSS loader configuration and apply it for .module.scss extensions like so:

const makeLoaderFinder = require('razzle-dev-utils/makeLoaderFinder');
const cssLoaderFinder = makeLoaderFinder('css-loader');
const paths = require('razzle/config/paths');

module.exports = {
  modify: (baseConfig, {dev}, webpack) => {
    const config = Object.assign({}, baseConfig);

    config.module.rules.filter(cssLoaderFinder).forEach(rule => {
        const isCssModuleRule = !rule.test.test('module.css');
        const scssExclude = [paths.appBuild];
        let scssTest = /\.s[ac]ss$/;
        if (isCssModuleRule) {
            scssTest = /\.module\.s[ac]ss$/;
        } else {
            scssExclude.push(/\.module\.s[ac]ss$/);
        }

        // Use default configs
        config.module.rules.push({
            test: scssTest,
            exclude: scssExclude,
            use: [
                ...rule.use,
                scssLoader,
            ]
        });
    });
  }
};

In the razzle.config.js
I expanded the configuration webpack.

const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const getCSSModuleLocalIdent = require('react-dev-utils/getCSSModuleLocalIdent');
const postcssNormalize = require('postcss-normalize');


const sassRegex = /\.(scss|sass)$/;
const sassModuleRegex = /\.module\.(scss|sass)$/;
const getStyleLoaders = (cssOptions, preProcessor) => {
    const loaders = [
        {
            loader: MiniCssExtractPlugin.loader
        },
        {
            loader: require.resolve('css-loader'),
            options: cssOptions,
        },
        {
            loader: require.resolve('postcss-loader'),
            options: {
                ident: 'postcss',
                plugins: () => [
                    require('postcss-flexbugs-fixes'),
                    require('postcss-preset-env')({
                        autoprefixer: {
                            flexbox: 'no-2009',
                        },
                        stage: 3,
                    }),
                    postcssNormalize(),
                ],
                sourceMap: false,
            },
        },
    ].filter(Boolean);
    if (preProcessor) {
        loaders.push({
            loader: require.resolve(preProcessor),
            options: {
                sourceMap: false,
            },
        });
    }
    return loaders;
};
module.exports = {
    modify: (config, { target, dev }, webpack) => {

        config.plugins.push(new MiniCssExtractPlugin({
            filename: 'static/css/bundle.[contenthash:8].css',
            chunkFilename: 'static/css/[name].[contenthash:8].chunk.css',
            allChunks: true,

        }))

        config.module.rules.push(
            {
                test: sassRegex,
                exclude: sassModuleRegex,
                use: getStyleLoaders(
                    {
                        importLoaders: 2,
                        sourceMap: false,
                    },
                    'sass-loader'
                ),
                sideEffects: true,
            },
            {
                test: sassModuleRegex,
                use: getStyleLoaders(
                    {
                        importLoaders: 2,
                        sourceMap: false,
                        modules: true,
                        getLocalIdent: getCSSModuleLocalIdent,
                    },
                    'sass-loader'
                ),
            }
        )
        return config;
    }
};

it's work

import './Home.css';
import s from './Home.module.css';
import './a.scss';
import a from './a.module.scss';

I created pull request https://github.com/jaredpalmer/razzle/pull/1047 in wich css scss, *.module.scss, *.module.css supports in default configuration