```ruby
require 'statsd'

module RadCore
  class Engine < ::Rails::Engine
    initializer :append_migrations do |app|
      unless app.root.to_s.match root.to_s
        config.paths['db/migrate'].expanded.each do |expanded_path|
          app.config.paths['db/migrate'] << expanded_path
        end
      end
    end

    initializer :factories, after: 'factory_girl.set_factory_paths' do
      if defined?(FactoryGirl)
        FactoryGirl.definition_file_paths << File.expand_path('../../../spec/factories', __FILE__)
      end
    end
  end
end
```

Add lib to autoload paths.
user
```ruby
require 'statsd'

module RadCore
  class Engine < ::Rails::Engine
    config.autoload_paths << root.join('lib')

    initializer :append_migrations do |app|
      unless app.root.to_s.match root.to_s
        config.paths['db/migrate'].expanded.each do |expanded_path|
          app.config.paths['db/migrate'] << expanded_path
        end
      end
    end

    initializer :factories, after: 'factory_girl.set_factory_paths' do
      if defined?(FactoryGirl)
        FactoryGirl.definition_file_paths << File.expand_path('../../../spec/factories', __FILE__)
      end
    end
  end
end
```
assistant