public function validate($subject): bool
    {
        if (isset($this->schema['items']) && \is_array($this->schema['items'])) {
            $schemaFirstKey = \array_keys($this->schema['items'])[0];
            $schemaType = \is_int($schemaFirstKey) ? 'array' : 'object';

            if ($schemaType === 'array') {
                if (!$this->validateAdditionalItems($subject, $this->schema)) {
                    return false;
                }
            }
        }
        return true;
    }