public function composerInstall() {
    $result = $this->taskExec(
      (DIRECTORY_SEPARATOR == "\\") ? 'set' : 'export' .
        " COMPOSER_EXIT_ON_PATCH_FAILURE=1 && composer install --ansi --no-interaction --optimize-autoloader --apcu-autoloader"
    )
      ->dir($this->getConfigValue('repo.root'))
      ->interactive($this->input()->isInteractive())
      ->setVerbosityThreshold(VerbosityThresholdInterface::VERBOSITY_VERBOSE)
      ->run();

    return $result;
  }