That looks really nice, thanks. However, I've sworn off Ruby as installing and maintaining the whole Gems stack is such a pain. I'd rather write a shell script, or conjure up some Python.
Just to kid myself, I ran `sudo gem install backup` on my CentOS 7 desktop. The CPU has been pegged for over a minute, I have no idea what it's doing. It's not using much memory, and I'm not sure if it is making or hanging on network requests.
EDIT: After a few minutes of warming the CPU, Ruby failed but at least with an informative error message.