Jens - With you 100% on a lot of what you said here, and having been the person on the other side I get how it's easy to take the side of the candidate vs the big bad employer (the employer, after all, almost never gets to tell their side). I do, however, have one little quibble:
"...publishing a private email conversation without letting the other party know and agree on it upfront is a no-go for me."
It's entirely / appropriately anonymized except for references to public repos...can't see at all why this should be held against him or even mentioned.
As for the rest of the take home, the replies sound like an ordinary code review to me...😂
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