Yeah, I guess a more recent biggish one was having to re-do a good deal of vector usage as those apis moved around and changed. But I would say my recent experience has been >90% crate moves and renames, which are really easy to deal with, especially with the right mindset of "I'm using pre-alpha software".

I also agree with whoever it was (you?) who pointed out elsewhere that the only reason people are even able to gripe about this stuff is that the development has been way more collaboratively open than other languages. That openness has its pros and cons!