code: void loadAdditionalServices(ServiceRegistry registry) {
          for (ResourceLoader loader : getResourceLoaders()) {
              for (Metadata<Service> metadata : ServiceLoader.load(Service.class, loader)) {
                  Service service = metadata.getValue();
                  for (Class<? extends Service> serviceInterface : Services.identifyServiceInterfaces(service.getClass(), new HashSet<>())) {
                      Services.put(registry, serviceInterface, service);
                  }
              }
          }
      }
docs: Discovers additional services using {@link ServiceLoader} and appends them to the given service registry.
  @param registry the given service registry