code: func (c *Config) StartApps() error {
  	for _, ap := range c.apps {
  		if err := ap.Start(); err != nil {
  			return fmt.Errorf("error starting app %v: %v", ap.ProgramName(), err)
  		}
  	}
  	return nil
  }
docs: // StartApps starts all the server applications that were configured
  // during InstallHandlers. It should only be called after perkeepd
  // has started serving, since these apps might request some configuration
  // from Perkeep to finish initializing.