func newRunner(creds) {
&ciRunner{
		githubClient:      newGithubClient(creds),
		githubCredentials: creds,
    // Note: buffered channel. Means that writes to `builds` will almost always return immediately,
    // unless we accumulate 100 builds in the queue. We don't have a good failure mode if that happens.
    // That's OK for now.
    builds: make(chan *event, 100),
	}
}

func main() {
  runner := newRunner()
  
  // background goroutine for doing one build at a time.
  go runner.startBuilder()

	for event := range server.Events {
    // this returns almost immediately
		runner.handleEvent(event)
	}
}


func (r *runner) startBuilder() {
  // Only one thing happening at a time here.
  for event := range r.builds {
    runBazelCommand(event)
     // etc.
    setCIStatusSuccess()
  }
}

func (r *runner) handleEvent(event) {
  setCIStatusPending()
  builds<-event
}