webpack.config.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');

module.exports = {
  entry: './src/index.jsx',
  output: {
    filename: 'bundle.js',
    path: path.resolve(__dirname, 'build'),
  },
  mode: process.env.NODE_ENV,
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env', '@babel/preset-react'],
          },
        },
        exclude: /node_modules/,
      },
      {
        test: /\.css$/,
        use: ['style-loader', 'css-loader'],
      },
      //   {
      //     test: /\.scss$/,
      //     use: ['style-loader', 'css-loader', 'sass-loader'],
      //   },
      {
        test: /\.less$/,
        use: ['style-loader', 'css-loader', 'less-loader'],
      },
      {
        test: /\.(png|jpe?g|gif)$/i,
        use: [
          {
            loader: 'file-loader',
          },
        ],
      },
      {
        test: /\.js$/,
        enforce: 'pre',
        use: ['source-map-loader'],
      },
    ],
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: './index.html',
    }),
  ],
  devServer: {
    static: {
      publicPath: '/build',
      directory: path.resolve(__dirname, 'public'),
    },
    proxy: {
      '/': 'http://localhost:3000',
    },
  },
};