public function isDrushAliasValid($alias) {
    $bin = $this->getConfigValue('composer.bin');
    $command = "'$bin/drush' site:alias @$alias --format=json";
    return $this->executor->execute($command)
      ->setVerbosityThreshold(VerbosityThresholdInterface::VERBOSITY_VERY_VERBOSE)
      ->run()
      ->wasSuccessful();
  }