Can't deploy to Heroku - EmberCli::DependencyError: No `ember-cli` executable found for `testapp`

[shanekoss]

Which operating system and version is the project developed on?
OSX 10.11.5
Which version of ruby is the project developed on?
2.4.1
Which version of npm is the project developed on?
3.10.10
Which version of ember-cli is the project developed on?
2.13.2
What is the rails version?
5.1.4
What is the ember-cli-rails version (from Gemfile)?
0.10.0
What is the ember-cli-rails-addon version (from package.json)?
^0.8.0
Is your application server multi-threaded
(such as puma and unicorn) or is it multi-process (such as thin and webrick)?
puma
What are the contents of config/initializers/ember.rb?
EmberCli.configure do |c|
c.app :testapp
end
How is the application deployed?
heroku

Test app runs fine locally but getting this error when trying to deploy to heroku.

followed all steps here: https://github.com/thoughtbot/ember-cli-rails

Any ideas? Thanks!

remote: -----> Preparing app for Rails asset pipeline
remote:        Running: rake assets:precompile
remote:        npm WARN package.json @ No repository field.
remote:        npm WARN package.json @ No license field.
remote:        npm WARN build_4ed292cd43786841af9deda8a203762f No repository field.
remote:        npm WARN build_4ed292cd43786841af9deda8a203762f No license field.
remote:        rake aborted!
remote:        EmberCli::DependencyError: No `ember-cli` executable found for `testapp`.
remote:        Install it:
remote:        $ cd /tmp/build_4ed292cd43786841af9deda8a203762f/testapp
remote:        $ npm install
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/path_set.rb:46:in `block in ember'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/path_set.rb:44:in `tap'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/path_set.rb:44:in `ember'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/command.rb:33:in `ember_build'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/command.rb:17:in `build'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/shell.rb:17:in `compile'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli/app.rb:43:in `compile'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli.rb:70:in `block in each_app'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli.rb:70:in `each'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli.rb:70:in `each_app'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/ember_cli.rb:52:in `compile!'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/ember-cli-rails-0.10.0/lib/tasks/ember-cli.rake:4:in `block (2 levels) in <top (required)>'
remote:        /tmp/build_4ed292cd43786841af9deda8a203762f/vendor/bundle/ruby/2.4.0/gems/rake-12.0.0/exe/rake:27:in `<top (required)>'
remote:        Tasks: TOP => assets:precompile => ember:compile
remote:        (See full trace by running task with --trace)
remote:  !
remote:  !     Precompiling assets failed.
remote:  !
remote:  !     Push rejected, failed to compile Ruby app.
remote: 
remote:  !     Push failed 

[nruth]

Did you follow https://github.com/thoughtbot/ember-cli-rails#heroku and add the nodejs buildpack?