progrium/dokku — pull request #229 by pnegahdar (2013-09-28 20:45:36+00:00)
Title: Keep .heroku and build on the existing image.

Closes issue #225

Basically runs the builder on the last version of the image with the everything in the app directory but .heroku deleted. This makes it so that if the environment already exists it simply builds on it (tested in python). If you want to force rebuild you simply delete the image in docker.