webpack.config.js

const path = require("path");
const webpack = require('webpack');

module.exports = {
   entry: {
       app: './index.jsx',
   },
   context: path.resolve(__dirname, "static_src"),
   output: {
       path: path.resolve(__dirname, "static", "build"),
       filename: 'app.js',
   },

   watch: process.argv[process.argv.length - 1] === 'development',

   module: {
       rules: [
           {
               test: /\.(js|jsx)$/,
               include: path.resolve(__dirname, "static_src"),
               loader: 'babel-loader',
               exclude: /node_modules/,
               options: {
                   presets: ['@babel/env', '@babel/react'],
                   plugins: [
                       [
                           "@babel/plugin-proposal-class-properties",
                           {
                               "loose": true
                           }
                       ]
                   ]

               }
           },
           {
               test: /\.css$/,
               loader: 'style-loader!css-loader',
           },
       ],
   },

    resolve: {
       modules: [`${__dirname}/static_src`, 'node_modules'],
       extensions: ['.js', '.jsx'],
    },

    devServer: {
      port: 8080,
      historyApiFallback: {
          index: 'index.html'
      }
    },

    devtool: 'cheap-inline-module-source-map',
};