public function update_8006000() {
    // Move files to blt subdir.
    $this->updater->moveFile('project.yml', 'blt/project.yml', TRUE);
    $this->updater->moveFile('project.local.yml', 'blt/project.local.yml',
      TRUE);
    $this->updater->moveFile('example.project.local.yml',
      'blt/example.project.local.yml', TRUE);

    // Delete symlink to hooks directory. Individual git hooks are now symlinked, not the entire directory.
    $this->updater->deleteFile('.git/hooks');
    $this->updater->getOutput()
      ->writeln('.git/hooks was deleted. Please re-run blt:init:git-hooks to install git hooks locally.');

    $this->updater->removeComposerRepository('https://github.com/mortenson/composer-patches');
    $this->updater->removeComposerScript('post-create-project-cmd');

    // Change 'deploy' module key to 'prod'.
    // @see https://github.com/acquia/blt/pull/700.
    $project_config = $this->updater->getProjectYml();
    if (!empty($project_config['modules']['deploy'])) {
      $project_config['modules']['prod'] = $project_config['modules']['deploy'];
      unset($project_config['modules']['deploy']);
    }

    $this->updater->getOutput()
      ->writeln("<comment>You MUST remove .travis.yml and re-initialize Travis CI support with `blt recipes:ci:travis:init`.</comment>");
  }