public static function buildBootstrap(Event $event)
    {
        $options = static::getOptions($event);
        $bootstrapDir = $autoloadDir = $options['symfony-app-dir'];

        if (static::useNewDirectoryStructure($options)) {
            $bootstrapDir = $options['symfony-var-dir'];
            if (!static::hasDirectory($event, 'symfony-var-dir', $bootstrapDir, 'build bootstrap file')) {
                return;
            }
        }

        if (!static::useSymfonyAutoloader($options)) {
            $autoloadDir = $options['vendor-dir'];
        }

        if (!static::hasDirectory($event, 'symfony-app-dir', $autoloadDir, 'build bootstrap file')) {
            return;
        }

        static::executeBuildBootstrap($event, $bootstrapDir, $autoloadDir, $options['process-timeout']);
    }