My webpack+gulp config

gulpfile.js

var notifier = require('node-notifier');
var gulp = require('gulp');
var g = require('gulp-load-plugins')();

var lr = require('tiny-lr');
var server = lr();
var minimist = require('minimist');

var env = minimist(process.argv.slice(2));
var debug = !!env.debug || !!env.d;
var watch = env._[0] === 'watch';

var webpack = require('webpack');
var webpack_cfg = require('./webpack.config.js');

gulp.task('scripts', ['lang'], function(cb) {
  webpack(webpack_cfg(watch, debug), function(err, stats) {
    if(stats.compilation.errors.length > 0) {
      console.log('============================================================');
      g.util.log(stats.compilation.errors[0].error.message);
      console.log('============================================================');
      if(watch) {
        notifier.notify({
          title: 'Error',
          message: stats.compilation.errors[0].error.message,
          wait: true,
          open: 'file://' + stats.compilation.errors[0].module.resource
        });
      }
    } else {
      g.util.log("[webpack]", stats.toString({
        colors: true
      }));

      gulp.src('index.php').pipe(g.livereload(server));
    }
  });
});

gulp.task('watch', ['scripts'], function() {
  server.listen(35729, function(err) {
    if(err) {
      console.log(err);
    }

    //start watch some tasks here
  });
});

gulp.task('default', ['scripts', 'images', 'svg', 'sass']);

webpack.config.js

var webpack = require('webpack');

module.exports = function(watch, debug) {
  watch = watch === undefined ? false : watch;
  debug = debug === undefined ? false : debug;
  return {
    entry: {
      app: './src/react/app.js',
      main: './src/js/legacy.js'
    },
    output: {
      path: __dirname + '/js',
      filename: '[name]-built.js'
    },
    resolve: {
      extensions: ['', '.js', '.js'],
      modulesDirectories: ['node_modules', 'bower_components', 'src/react']
    },
    devtool: '#source-map',
    watch: watch,
    module: {
      loaders: [
        {test: /\.js$/, exclude: /node_modules/, loader: 'babel'},
        {test: require.resolve('react'), loader: 'expose?React'},
        {test: require.resolve('immutable'), loader: 'expose?Immutable'}
      ],
    },
    externals: {
      "jquery": "jQuery"
    },
    plugins: [
      debug && new webpack.optimize.UglifyJsPlugin(),
      new webpack.DefinePlugin({
        'process.env': {
          'NODE_ENV': JSON.stringify(debug ? 'development' : 'production')
        }
      }),
      new webpack.ContextReplacementPlugin(/moment[\/\\]locale$/, /ru|es|uk/),
      new webpack.optimize.CommonsChunkPlugin({
        filename: 'common-built.js',
        minChunks: 2
      }),
      new webpack.ProvidePlugin({
        to5Runtime: "imports?global=>{}!exports?global.to5Runtime!babel/runtime"
      })
    ],
  };
};