Atuin is my longest-running project and certainly the most successful (depending on your measure of success). It synchronises shell history between all of your machines, keeps an e2e encrypted backup, and has a nice terminal search UI.
For years I have thought that shell history could be improved. I was often working across multiple machines, and searching for commands I had ran months prior. Why couldn’t I have all the history I’d ever ran, on all machines, at all times?
Atuin was written to try and solve that problem. I originally named it “shync”, from shell and sync, but luckily managed to choose something better.