Is meteor magically browserifying everything in 1.3?

I noticed a few things that seemed a little interesting in 1.3. Not sure why, but I tried this on a client file.

import {EventEmitter} from 'events';

class AsyncOperation extends EventEmitter {
  constructor() {
  async run() {}

It seemed to magically work. How is this happening? Are node packages that can be browserified being automatically browserified?

Yes, Meteor 1.3 allows using for NPM modules on client. Same as browserify and webpack.