Stacked Git, is an application for managing Git commits as a stack of patches
stacked-git.github.ioThis seems like it's another attempt to 'simplify' working with Git by layering another model on top with a reduced command set.
Somewhat like how you could do everything with git objects and refs but branches and tags make it easier.
But I do worry that just how occasionally a regular Git users needs git reflog to fix a problem, that a StGit user will still have to fallback to Git and that as such, it's just another layer of onion.
That's kind of the point. Both mercurial and darcs had such a feature. I wasn't an avid Mercurial user, but I think it might have been mercurial queues.