app.rb

  def run_in_background(&block)
    Process.fork do
      Process.fork do
        puts "Launching Background Process"
        Daemons.call &block
        puts "Background Process has been Launched"
      end
      exit
    end
  end

  get '/first' do
    puts "start FIRST action"
    run_in_background {puts "HI"; sleep 20; puts "BYE"; }
    puts "finish FIRST action"
    redirect("/second")
  end

  get '/second' do
    "This is the SECOND action<br/><a href='/first'>go to first</a>"
  end