A little background: I wrote this simple pair of scripts to save me time and effort at work. I am currently working on a software project that needs frequent rebuilding, so wrote my own custom build script. After the second or third time I accidentally overwrote my most recent changes and lost some small amount of work, I decided that I wanted to back up every time I built the thing.
Secondly, now that the project is being distributed and others are testing it, I get bug reports saying "I found this bug using the version from the 18th of August, can you reproduce it and fix it?". I need to be able to do that, so needed an easily accessible copy of the older versions of the project to recreate bugs on.
Having stored versions of your old code also makes fixing regressions (breaking things that you previously had working) a snap- you flick back through your old versions to find the point at which one version works and the one after it doesnt, find the differences between the two and your problem will be right there.
I decided to write this up
a) to share my work with people who might appreciate it
b) lest anyone suggest all I do is bitch about Instructables about batch files and never contribute any useful ones myself.
Please Note: I have licensed this as "all rights reserved" because it's possible that my employer owns the IP to this project, not me. As such I can't license it for modification and redistribution, so please don't redistribute this code. If you want to point people in the direction of the Instructable, however...