docs: @SuppressWarnings("unchecked")
    public final IntCache<V> buildForIntKey() {
      Cache2kConfiguration<K,V> cfg = config();
      if (cfg.getKeyType().getType() != Integer.class) {
        throw new IllegalArgumentException("Integer key type expected, was: " + cfg.getKeyType());
      }
      return (IntCache<V>) CacheManager.PROVIDER.createCache(manager, config());
    }