This is intriguing, but it kind of goes against the essence of running Dokku.<p>We run Dokku because it's absolutely dead simple. It's not the fastest nor is it particularly scalable, but it works. There will be a point where we can't scale with just Dokku, but we'll cross that bridge when we come to it.
I do something similar - mostly because buildpack downloads seen to time out ever second time. Just wish I could find a trivial way to cache installed gems to really get things flying along.