TLDR Summary: Backup a file when it has changed and rotate the backups.
So I have this habit of playing FTL: Faster Than Light, which is fun and fantastic!
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But recently I lost some progress because my profile got corrupted. I was able to get an old save from Apple's Time Machine file history backups, but I didn't want to start playing again until I had a way to ensure that there would be a history of backups created as I play the game.
Also I wanted a reason to get hands-on with GoLang again.
Thus it came to pass that I created software for something that could have been easily solved with plan old gnu tools and maybe some Bash scripting. No regrets. This was a fun bit of coding that I wanted to do for my own selfish reasons.