pylon:
Do you know git (https://git-scm.com)?
I don't like Git. My brain doesn't work that way. I store all of my Arduino stuff in a Subversion repository. It does the same thing; it just starts from a different concept.
With some Arduino-based devices, I've downloaded the hex file off the device and saved it in Subversion. Then I have a backup of what was on it when it was delivered. With only a little command-line effort, I can put that file back onto the device.