protected function deleteDeliveryRuntime(core_kernel_classes_Resource $assembly)
    {
        /** @var GroupAssignment $deliveryAssignement */
        $deliveryAssignement = $this->getServiceManager()->get(GroupAssignment::SERVICE_ID);
        $deliveryAssignement->onDelete($assembly);
        /** @var core_kernel_classes_Resource $runtimeResource */
        $runtimeResource = $assembly->getUniquePropertyValue(new core_kernel_classes_Property(self::PROPERTY_DELIVERY_RUNTIME));
        return $runtimeResource->delete();
    }