$code = array_reduce(
    get_defined_functions()['internal'] ?? [],
    function (string $carry, string $original): string {
        $alias = lcfirst(
            str_replace(
                ' ',
                '',
                ucwords(
                    str_replace(
                        ['-', '_'],
                        ' ',
                        $original
                    )
                )
            )
        );
        
        if ($alias != $original
            && !empty($alias)
            && !function_exists($alias)
        ) {
            // @todo Use reflection on the original to inherit
            // parameter list.
            $carry .= sprintf(
                <<<'FUNCTION'
if (!function_exists('%1$s')) {
    /**
     * @see %2$s
     */
    function %1$s (...$arguments) {
        return %2$s(...$arguments);
    }
}


FUNCTION
,
                $alias,
                $original
            );
        }
        
        return $carry;
    },
    '<?php' . PHP_EOL
);

// This should be solved with some sort of caching mechanism, to prevent
// having to do this every time.
$storage = tempnam(sys_get_temp_dir(), 'camelCasedInternalFunctions');

file_put_contents($storage, $code);
require $storage;

<?php
$storage = sprintf(
    __DIR__ . '/aliases.%s.php',
    md5(
        implode(
            ':',
            get_defined_functions()['internal'] ?? []
        )
    )
);