require "sinatra" require "sprockets/traceur" class SinatraApplication < Sinatra::Base set :raise_errors, true set :show_exceptions, false get "/" do erb :index end end SinatraSample = Rack::Builder.new do map "/assets" do root = File.dirname(__FILE__) environment = Sprockets::Environment.new environment.append_path root + '/js' run environment end map "/" do run SinatraApplication end end