Example Webpack Config for Static Sites

package.json

{
  "name": "static-site",
  "version": "2.1.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "run-s webpack-prod hugo-prod",
    "dev": "run-p webpack-dev hugo-dev",
    "hugo-dev": "wait-on assets/dist && hugo server",
    "hugo-prod": "hugo",
    "webpack-dev": "webpack --mode development --env.production=false --watch",
    "webpack-prod": "webpack --mode production --env.production"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "private": true,
  "browserslist": "> 0.25%, not dead",
  "devDependencies": {
    "@babel/core": "^7.4.5",
    "@babel/preset-env": "^7.4.5",
    "babel-loader": "^8.0.6",
    "clean-webpack-plugin": "^2.0.2",
    "css-loader": "^2.1.1",
    "file-loader": "^3.0.1",
    "friendly-errors-webpack-plugin": "^1.7.0",
    "mini-css-extract-plugin": "^0.6.0",
    "npm-run-all": "^4.1.5",
    "sass": "^1.20.1",
    "sass-loader": "^7.1.0",
    "style-loader": "^0.23.1",
    "uglifyjs-webpack-plugin": "^2.1.3",
    "wait-on": "^3.2.0",
    "webpack": "^4.32.1",
    "webpack-cli": "^3.3.2"
  },
  "dependencies": {
    "bootstrap": "^4.3.1",
    "jquery": "^3.4.1",
    "popper.js": "^1.15.0"
  }
}

webpack.config.js

const { resolve } = require('path')
const MiniCssExtractPlugin = require('mini-css-extract-plugin')
const FriendlyErrorsWebpackPlugin = require('friendly-errors-webpack-plugin')
const UglifyJsPlugin = require('uglifyjs-webpack-plugin')
const CleanWebpackPlugin = require('clean-webpack-plugin')

module.exports = (env, argv) => {
    return {
        entry: [
            resolve(__dirname, 'src', 'js', 'main.js'),
            resolve(__dirname, 'src', 'scss', 'main.scss'),
        ],

        output: {
            filename: '[name].js',
            path: resolve(__dirname, 'assets', 'dist'),
            publicPath: '/dist/'
        },

        module: {
            rules: [
                {
                    test: /\.(sa|sc|c)ss$/,
                    use: [
                        {
                            loader: MiniCssExtractPlugin.loader,
                            options: { publicPath: 'assets/styles' }
                        },
                        {
                            loader: 'css-loader',
                            options: {
                                sourceMap: true,
                                importLoaders: 2,
                                url: false
                            }
                        },
                        {
                            loader: 'sass-loader',
                            options: { 
                                sourceMap: true,
                                implementation: require("sass")
                            }
                        }
                
                    ]
                },
                {
                    test: /\.(png|svg|jpg|gif)$/,
                    use: ['file-loader']
                },
                {
                    test: /\.m?js$/,
                    exclude: /(node_modules|bower_components)/,
                    use: {
                        loader: 'babel-loader',
                        options: {
                            presets: ['@babel/preset-env']
                        }
                    }
                },
            ]
        },

        plugins: [
            new MiniCssExtractPlugin({
                filename: "[name].css",
            }),
            new CleanWebpackPlugin({
                cleanOnceBeforeBuildPatterns: ['assets/dist']
            }),
            new FriendlyErrorsWebpackPlugin(),
        ],

        optimization: {
            splitChunks: {
                chunks: 'all'
            },
            minimizer: [new UglifyJsPlugin()]
        },
        
        performance: {
            maxEntrypointSize: 400000
        },

        watchOptions: {
            ignored: ['node_modules']
        },
    }
}