def use_default_serfer_stage
      use Serf::Middleware::ParcelFreezer
      use Serf::Middleware::PolicyChecker, policy_chain: @policy_chain
      use Serf::Serfer
    end
def use_default_serfer_stage
      use Serf::Middleware::ParcelFreezer
      use Serf::Middleware::PolicyChecker, policy_chain: @policy_chain
      use Serf::Serfer
    end
Add the following middleware to the chain:

   use Serf::Middleware::ParcelFreezer
   use Serf::Middleware::PolicyChecker, @policy_chain
   use Serf::Serfer