src/Reaction.php
protected static function locateClassLoader()
    {
        $cwd = getcwd();
        $path = $cwd . DIRECTORY_SEPARATOR . 'vendor/autoload.php';
        if (!file_exists($path) || !is_file($path)) {
            return null;
        }
        return include $path;
    }
protected static function locateClassLoader()
    {
        $cwd = getcwd();
        $path = $cwd . DIRECTORY_SEPARATOR . 'vendor/autoload.php';
        if (!file_exists($path) || !is_file($path)) {
            return null;
        }
        return include $path;
    }
Get composer class loader
@return null|\Composer\Autoload\ClassLoader