webpack.config.js

const path = require('path');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');

module.exports = {
  entry: ['babel-polyfill', path.normalize(__dirname + '/src/js/index')],
  devtool: 'cheap-module-source-map',
  output: {
    filename: 'bundle.js',
    path: path.join(__dirname, 'dist'),
    publicPath: '/public/',
  },
  module: {
    rules: [
      {
        test: /\.js|jsx$/,
        exclude: /node_modules/,
        include: [path.resolve(__dirname, 'src', 'js')],
        use: [
          {
            loader: 'babel-loader',
            options: {
              plugins: ['transform-runtime', 'transform-object-rest-spread'],
              presets: ['env', 'react']
            },
          },
          {
            loader: path.resolve(__dirname, 'lib', 'featureEnabler.js'),
            options: {
              filter: true
            }
          }
        ]
      }, {
        test: /\.(sa|sc|c)ss$/,
        use: [
          'css-hot-loader',
          MiniCssExtractPlugin.loader,
          {
            loader: 'css-loader',
            options: {
              importLoaders: 2,
            },
          },
          {
            loader: 'postcss-loader',
            options: {
              ident: 'postcss',
              plugins: () => {
                require('autoprefixer')();
              },
            },
          },
          'sass-loader',
        ],
      },
    ],
  },
  devServer: {
    contentBase: path.join(__dirname, 'public'),
    hot: true,
  },
  plugins: [
    new CleanWebpackPlugin(['dist']),
    new MiniCssExtractPlugin({
      filename: '[name].css',
      chunkFilename: '[id].css',
    }),
  ],
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        cache: true,
        parallel: true,
        sourceMap: true,
      }),
      new OptimizeCSSAssetsPlugin({}),
    ],
  },
  resolve: {
    extensions: ['.js', '.jsx'],
  },
};