webpack.config.dev.js

const path = require("path");
const { CleanWebpackPlugin } = require("clean-webpack-plugin");
const HtmlWebpackPlugin = require("html-webpack-plugin");

module.exports = {
  mode: "development",
  entry: {
    main: "./src/index.js",
  },
  output: {
    filename: "[name].js",
    path: path.resolve(__dirname, "dist"),
    publicPath: "/",
  },
  module: {
    rules: [
      {
        test: /\.css$/,
        use: ["style-loader", "css-loader"],
      },
      {
        test: /\.(sass|scss)$/,
        use: ["style-loader", "css-loader", "sass-loader"],
      },
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env"],
            plugins: ["@babel/plugin-proposal-class-properties"],
          },
        },
      },
    ],
  },
  plugins: [
    new CleanWebpackPlugin(),
    new HtmlWebpackPlugin({
      template: "./src/index.html",
    }),
  ],
  devServer: {
    open: true,
    static: {
      directory: path.join(__dirname, "src"),
    },
    compress: true,
    port: 9000,
  },
};