```ruby
module RubyWedding
  class Engine < ::Rails::Engine
    isolate_namespace RubyWedding

    config.generators do |g|
      g.test_framework :rspec, fixture: false
      g.fixture_replacement :factory_girl, dir: 'spec/factories'
      g.assets false
      g.helper false
    end

  end
end
```

Allow decorators in the parent app.
user
```ruby
module RubyWedding
  class Engine < ::Rails::Engine
    isolate_namespace RubyWedding

    config.generators do |g|
      g.test_framework :rspec, fixture: false
      g.fixture_replacement :factory_girl, dir: 'spec/factories'
      g.assets false
      g.helper false
    end

    config.to_prepare do
      Dir.glob(Rails.root + "app/decorators/**/**/*_decorator*.rb").each do |c|
        require_dependency(c)
      end
    end
  end
end
```
assistant