webpack.config.js

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

module.exports = {
    entry: './src/index.js',
    output: {
        path: path.resolve(__dirname, 'dist'),
        filename: 'bundle.js'
    },
    resolve: {
        // see below for an explanation
        alias: {
            svelte: path.resolve('node_modules', 'svelte')
        },
        extensions: ['*', '.mjs', '.js', '.svelte'],
        mainFields: ['svelte', 'browser', 'module', 'main']
    },
    module: {
        rules: [
            {
                test: /\.(png|jpe?g|gif)$/i,
                use: [
                    {
                        loader: 'file-loader',
                    },
                ],
            },
            {
                test: /\.js?$/,
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader'
                }
            },
            {
                test: /\.svelte$/,
                use: {
                    loader: 'svelte-loader'
                }
            },
            {
                test: /\.(scss)$/,
                use: [
                    {
                        // Adds CSS to the DOM by injecting a `<style>` tag
                        loader: 'style-loader'
                    },
                    {
                        // Interprets `@import` and `url()` like `import/require()` and will resolve them
                        loader: 'css-loader'
                    },
                    {
                        // Loader for webpack to process CSS with PostCSS
                        loader: 'postcss-loader',
                        options: {
                            plugins: function () {
                                return [
                                    require('autoprefixer')
                                ];
                            }
                        }
                    },
                    {
                        // Loads a SASS/SCSS file and compiles it to CSS
                        loader: 'sass-loader'
                    }
                ]
            }
        ]
    },
    plugins: [
        new HtmlWebpackPlugin({
            inject: true,
            template: './public/index.html',
            filename: './index.html'
        })
    ]
}