private <U> U withRegistrations(Function<NamedDomainObjectSet<BuildServiceRegistration<?, ?>>, U> function) {
        registrationsLock.lock();
        try {
            return function.apply(registrations);
        } finally {
            registrationsLock.unlock();
        }
    }

    @Override
    public NamedDomainObjectSet<BuildServiceRegistration<?, ?>> getRegistrations() {
        return registrations;
    }