Basic webpack configuration

webpack.config.js

# Minimal webpack.config.js
module.exports = {
 mode: "production",
 entry: {
  "app": "./src/index.js",
 },
 module: {
  rules: [
   {
    test: /\.css$/,
    use: ["style-loader", "css-loader"],
    exclude: /node_modules/,
   },
   {
    test: /\.js$/,
    loader: "babel-loader",
    exclude: /node_modules/,
   }
  ],
 },
 output: {
  path: __dirname+"/build",
  filename: "bundle.js",
 },
}