If you don't mind using Ruby instead of Python, this sounds a lot like Chef. All my Chef scripts wind up using a bunch of off-the-shelf cookbooks to install Pos

If you don't mind using Ruby instead of Python, this sounds a lot like Chef. All my Chef scripts wind up using a bunch of off-the-shelf cookbooks to install Postgres, Nginx, etc., then an app-specific recipe to do the rest. A recipe is just Ruby code (augmented with Chef's "resources"), and you can run code on the server with the ruby_block or bash resource. You can also import cookbooks to define more resources (or LWRPs). If you use chef-solo, librarian-chef, and knife solo, you cut out a lot of the complexity too.