webpack 4: Webpack dev server + proxy + hot reloading working

package.json

{
  "name": "webpack-4-quickstart",
  "version": "1.0.0",
  "main": "index.js",
  "scripts": {
    "precommit": "lint-staged",
    "dev": "webpack-dev-server --mode development ./src/scripts/index.js --open",
    "build": "webpack --mode production ./src/scripts/index.js"
  },
  "lint-staged": {
    "src/**/*.{js,json,css,md}": [
      "eslint",
      "prettier --write",
      "git add"
    ]
  },
  "keywords": [],
  "devDependencies": {
    "babel-core": "^6.26.0",
    "babel-eslint": "^8.2.2",
    "babel-loader": "^7.1.2",
    "babel-preset-env": "^1.6.1",
    "breakpoint-sass": "^2.7.1",
    "breakpoint-slicer": "^2.0.0",
    "css-loader": "^0.28.10",
    "eslint": "^4.18.2",
    "eslint-loader": "^2.0.0",
    "extract-text-webpack-plugin": "^4.0.0-beta.0",
    "file-loader": "^1.1.11",
    "html-loader": "^0.5.5",
    "html-webpack-plugin": "^3.0.4",
    "husky": "^0.14.3",
    "image-webpack-loader": "^4.1.0",
    "lint-staged": "^7.0.0",
    "node-sass": "^4.7.2",
    "prettier": "^1.11.1",
    "pug": "^2.0.0-rc.4",
    "pug-loader": "https://github.com/pugjs/pug-loader/tarball/master",
    "sass-loader": "^6.0.7",
    "style-loader": "^0.20.2",
    "webpack": "^4.0.0",
    "webpack-cli": "^2.0.10",
    "webpack-dev-server": "^3.1.0",
    "webpack-notifier": "^1.5.1"
  },
  "dependencies": {}
}

webpack.config.js

const HtmlWebPackPlugin = require('html-webpack-plugin')
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const WebpackNotifierPlugin = require('webpack-notifier')
const path = require('path')

const appDirectory = path.resolve(__dirname, './../')
const localAppBackendUrl = 'http://localhost:48000/'

module.exports = {
  output: {
    path: `${appDirectory}landpages/static/`,
    publicPath: `${localAppBackendUrl}static/`,
    filename: 'js/[name].js'
  },
  module: {
    rules: [
      {
        test: /\.scss$/,
        use: ExtractTextPlugin.extract({
          use: [
            {
              loader: 'css-loader',
              options: {
                minimize: true,
              },
            },
            {
              loader: 'sass-loader',
            },
          ],
          fallback: 'style-loader',
          allChunks: true,
        }),
      },
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: ['babel-loader', 'eslint-loader'],
      },
      {
        test: /\.html$/,
        use: [
          {
            loader: 'html-loader',
            options: { minimize: false },
          },
        ],
      },
      {
        test: /\.(gif|png|jpe?g|svg)$/i,
        use: { 
          loader: 'file-loader',
          options: {
            name: '[name].[ext]',
            outputPath: 'img/'
          }
          // {
          //   loader: 'image-webpack-loader',
          //   options: {
          //     mozjpeg: {
          //       progressive: true,
          //       quality: 65,
          //     },
          //     // optipng.enabled: false will disable optipng
          //     optipng: {
          //       enabled: false,
          //     },
          //     pngquant: {
          //       quality: '65-90',
          //       speed: 4,
          //     },
          //     gifsicle: {
          //       interlaced: false,
          //     },
          //   },
          // },
        },
      },
      {
        test: /\.pug$/,
        use: {
          loader: 'pug-loader',
          query: {}, // Can be empty
        },
      },
    ],
  },
  resolve: {
    alias: {
      assets: path.resolve(__dirname, 'src/assets/'),
    },
  },
  devServer: {
    openPage: 'home-alarm/',
    historyApiFallback: true,
    noInfo: true,
    headers: { 'Access-Control-Allow-Origin': '*' },
    port: 8020,
    quiet: true,
    proxy: {
      '/': {
        target: localAppBackendUrl,
        changeOrigin: true
      }
    }
  },
  node: {
    fs: 'empty'
  },
  plugins: [
    new ExtractTextPlugin('css/[name].css'),
    new WebpackNotifierPlugin({
      alwaysNotify: true,
      skipFirstNotification: true,
    }),
  ],
}