private function helpers()
    {
        $HELPERS_FILE = [];
        // From base
        if (file_exists($pathHelpers = VENDOR_KNOB_BASE_DIR . '/src/config/' . static::HELPERS_FILE . '.php')) {
            $HELPERS_FILE += include $pathHelpers;
        }
        // From App
        if (file_exists($pathHelpers = APP_DIR . '/config/' . static::HELPERS_FILE . '.php')) {
            $HELPERS_FILE += include $pathHelpers;
        }

        return array_merge([
            'case' => [
                'lower' => function ($value) {
                    return strtolower((string)$value);
                },
                'upper' => function ($value) {
                    return strtoupper((string)$value);
                },
            ],
            'count' => function ($value = []) {
                return count($value);
            },
            'moreThan1' => function ($value = []) {
                return count($value) > 1;
            },
            'date' => [
                'xmlschema' => function ($value) {
                    return date('c', strtotime($value));
                },
                'string' => function ($value) {
                    return date('l, d F Y', strtotime($value));
                },
                'format' => function ($value) {
                    return date(get_option('date_format'), strtotime($value));
                },
            ],
            'toArray' => function ($value) {
                return explode(',', $value);
            },
            'ucfirst' => function ($value) {
                return ucfirst($value);
            },
        ], $HELPERS_FILE);
    }