Lifeboat would be the part before you press Publish in RapidWeaver. You would use Lifeboat to first configure a new vps instance so that it can serve your website. Then you use RW to publish the content. I use RW for my blog 
I’ve been avoiding marketing Lifeboat as a general web developer tool because it lacks some features that other web panels offer. I might be too self conscious about it to assert myself there.