running Exorcist with Grunt Browserify after bundle creation

browserify.js

// This will create a readable stream that we can pipe our bundle to Exorcist with

var stream = require('stream');
var grunt = require('grunt');
var exorcist = require('exorcist');

var createSourceMap = function(err, src, next) {
  var mapfile = grunt.template.process('<%= folders.output %>/<%= filenames.js %>.map');
  var s = new stream.Readable();
  s._read = function noop() {};
  s.push(src);
  s.push(null);
  s.pipe(exorcist(mapfile).on('finish', function() {
    next(err, src);
  }));
};

module.exports = {
  development: {
    options: {
      bundleOptions: {
        debug: true
      },
      postBundleCB: createSourceMap
    },
    dest: 'destination.js',
    src: 'source.js'
  }
};