gistfile1.rb

      def on_message(message)
        when Aggregate::Message
          instance_of(message.aggregate, message.id).message(message.message, envelope.ivar)
          Behaviour::MESSAGE_PROCESSED
        end
      end

gistfile2.rb

      def on_message(message)
        when Aggregate::Message
          redirect instance_of(message.aggregate, message.id), Concurrent::Actor::Envelope.new(message.message, envelope.ivar, Concurrent::Actor.current, self.reference)
        end
      end