Over the years I've been surprised a number of times by seeing Apple hire a particular software engineer that I wouldn't hire for my own little company. You're still kinda junior @ 4 years there, but.. have you seen seen any slippage in hiring standards?
Apple hiring is independent per team. You can literally interview forever at apple and the way each team interviews is wildly variant. Had some pretty cool interview loops. I got rejected and then got an offer after interview 4 or 5 with a team on a high profile app that I really liked.
Apple doesn't give good offers although, so I took another one at a company / team I also really liked with a better offer.
