Webpack config with dev server

webpack.config.js

module.exports = {
  entry:  __dirname + "/app/main.js",
  output: {
    path: __dirname + "/public",
    filename: "app.js"
  },
  devServer: {
    contentBase: "./public",
    historyApiFallback: true,
    inline: true,
    port: 3001
  } 
};