public function linkComposer($options = ['blt-path' => InputOption::VALUE_REQUIRED]) {
    $composer_json_filepath = $this->getConfigValue('repo.root') . '/composer.json';
    $composer_json = json_decode(file_get_contents($composer_json_filepath));
    $composer_json->repositories->blt = [
      'type' => 'path',
      'url' => $options['blt-path'],
    ];
    $composer_json->require->{'acquia/blt'} = '*';

    file_put_contents($composer_json_filepath, json_encode($composer_json, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES));

    $this->taskExec('composer update acquia/blt --with-dependencies')
      ->dir($this->getConfigValue('repo.root'))
      ->run();
  }