code: public function prepareJob(Job $job)
      {
          $origin = $job->getParameters()['origin'];
          $target = $this->buildPath.DIRECTORY_SEPARATOR. $job->getDirectory();
          $build  = $job->getParameters()['build'];
  
          // First mirroring target
          $this->filesystem->mirror($origin, $target, null, array(
              'delete'   => true,
              'override' => true,
          ));
  
          // Second override target with build dir
          $this->filesystem->mirror($build, $target, null, array(
              'delete'   => false,
              'override' => true,
          ));
      }
docs: {@inheritdoc}