module Middleman::Renderers::Slim

def registered(app)

Once registered
def registered(app)
  app.before_configuration do
    template_extensions :slim => :html
  end
  # Setup Slim options to work with partials
  ::Slim::Engine.set_default_options(
    :buffer    => '@_out_buf', 
    :generator => ::Temple::Generators::StringBuffer
  )
end