How does ember transpile modules? I understand that it doesn't use ember-cli-babel(https://www.npmjs.com/package/ember-cli-babel#about-modules) So where can I find details on ember's ES6 module transpiler
Up until ember-cli 1.13.8 it used this package: https://www.npmjs.com/package/broccoli-es6modules, which is a wrapper for the esperanto library. You can see that in the package.json file here: https://github.com/ember-cli/ember-cli/blob/v1.13.8/package.json#L80
However, with ember-cli 1.13.9 it was indeed updated to use the broccoli-babel-transpiler package; see https://github.com/ember-cli/ember-cli/blob/v1.13.9/package.json#L72