Is the whole program uploaded even if only one byte changed?

guix:
I'm already at 2000+ uploads I think, and I haven't even done 10% of the code for my project, just testing things...

Is this an exaggeration? I can't imagine how a project small enough to fit on an Arduino could require 2000 attempts to get 10% of it working. Are you uploading the code when you meant to just verify it, or something? You'd have to be uploading every five minutes for weeks on end to reach that sort of number of uploads.