Rails 5 API + ActiveAdmin + create-react-app on Heroku

rails g active_admin:install

Running via Spring preloader in process 49455
      invoke  devise
    generate    No need to install devise, already done.
      invoke    active_record
      create      db/migrate/20170228184603_devise_create_admin_users.rb
      create      app/models/admin_user.rb
      invoke      test_unit
      create        test/models/admin_user_test.rb
      create        test/fixtures/admin_users.yml
      insert      app/models/admin_user.rb
       route    devise_for :admin_users
        gsub    app/models/admin_user.rb
        gsub    config/routes.rb
      append    db/seeds.rb
      create  config/initializers/active_admin.rb
      create  app/admin
      create  app/admin/dashboard.rb
      create  app/admin/admin_user.rb
      insert  config/routes.rb
    generate  active_admin:assets
Running via Spring preloader in process 49502
      create  app/assets/javascripts/active_admin.js.coffee
      create  app/assets/stylesheets/active_admin.scss
      create  db/migrate/20170228184607_create_active_admin_comments.rb