How to include polyfill?

I’m trying to use Symbol and the babel page says I need to include the polyfill

What is the best approach to include the polyfill in an ember cli project?

[BrianSipple]

I’ve noticed that this is the first thing shown by Google when you search “ember babel polyfill”.

For any of those folks looking for an answer, please set the includePolyfill property of the ember-cli-babel hash in your ember-cli-build.js file to true:

var app = new EmberApp({
  'ember-cli-babel': {
    includePolyfill: true
  }
});

Edited after the heads-up from @iNaD.

[iNaD]

For further reference if someone will find this Issue. With BrianSipple’s solution you will get a deprecation warning with current versions DEPRECATION: Putting the "includePolyfill" option in "babel" is deprecated, please put it in "ember-cli-babel" instead.

So the correct solution for newer versions is:

var app = new EmberApp({
  'ember-cli-babel': {
    includePolyfill: true
  }
});