Working with the ember-rails gem and Heroku require some application settings that aren’t immediately intuative.
For ember-rails, you need to tell Rails which variant of ember to use. This is done in your application config.
Heroku doesn’t play nice with the default Rails asset pipeline settings. You’ll need to configure your Rails app to serve up the assets in production.
config/environments/development.rb you can set ember to use the development variant.
And with that, deployment is as easy as
git push heroku master.