The first prerelease of git-annex was made ten years ago. Taking a look back at 0.01, which I think only I ever used, it had the commands add, get, drop, unannex, init, fix, and fromkey. There were 2600 lines of code in all, which has increased 30-fold.
Later that week, 0.02 added the move command. I've been working recently on fixing a ?tricky problem with resuming interrupted moves. The move command has been surprisingly subtle to get just right, since it turns out to not be as simple as a get followed by a drop -- numcopies checks that would prevent a drop sometimes need to be relaxed to allow a move. Maybe I've finally gotten it perfect now. Probably not.