It's great for running unit tests on save, or hacking on python script and re-execute them when you need.

I often use something like this when iterating over stuff. This is a quick hack to list files I touched and differ from main.

    git diff main --name-only --relative | entr -r -c my-command

This of course needs to be killed and re-run if you want to pick up new files

That's a great tip!