> I have to basically get the mental model of the codebase in my head no matter what.

Ah yes, I feel this too! And that's much harder with someone else's code than with my own.

I unleashed Google's Jules on my toy project recently. I try to review the changes, amend the commits to get rid of the worst, and generally try to supervise the process. But still, it feels like the project is no longer mine.

Yes, Jules implemented in 10 minutes what would've taken me a week (trigonometry to determine the right focal point and length given my scene). And I guess it is the right trigonometry, because it works. But I fear going near it.