Brocfile.js

var dist   = require('broccoli-dist-es6-module');
var esNext = require('broccoli-esnext');

var tree = esNext('lib');

module.exports = dist(tree, {

  // the entry script, and module that becomes the global
  main: 'main',

  // will become window.ic.ajax with the exports from `main`
  global: 'mylib',

  // the prefix for named-amd modules
  packageName: 'mylib',

  // global output only: naive shimming, when the id 'ember' is imported,
  // substitute with `window.Ember` instead
  shim: {
    'ember': 'Ember'
  }
});

lib-main.js

import Utils from './utils';

export default () => {
  console.log(Utils.add(1, 2));
}

lib-utils.js

export default (a, b) => {
  return a + b;
}

package.json

{
  "name": "compile",
  "version": "0.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "broccoli": "^0.12.3",
    "broccoli-dist-es6-module": "^0.2.0",
    "broccoli-esnext": "^0.2.0"
  }
}