module.exports = {
  devtool: 'source-map',
  module: {
    loaders: [
      { test: /\.tsx?$/, use: 'ts-loader' }
    ]
  },
  resolve: {
    extensions: [ '.tsx', '.ts', '.js' ]
  },
  output: {
    filename: 'bundle.js'
  }
}

module.exports = {
  mode: "development",
  devtool: "source-map",
  module: {
    rules: [
      {
        test: /\.tsx?$/,
        use: "ts-loader",
        exclude: /node_modules/
      }
    ]
  },
  resolve: {
    extensions: [".tsx", ".ts", ".js"]
  },
  output: {
    filename: "bundle.js"
  }
};

Update webpack config