First, thanks for a well-considered and detailed response instead of just calling me a bigot for noting that he was needlessly difficult to understand. On that I see the same issue as in his code: Just Barely Good Enough. He’d learned the words but not the pronunciation. In his code he had learned the HOW but had no grasp of the WHY and in both cases he was uninterested in closing the loop.
By the time the API issue happened I was about done there, and I had tried much of what you said with this guy many times. He was unreceptive. But I think you’re off the mark on his insecurity; he figured he knew it all. I had at least four times his experience but he wasn’t interested in anything I had to say. I think his only imperative was the clearing of his task list. He was the only one on the project who emailed his every commit. Not a PR, just the spew. Useless information. “Fixed spelling error in comment.”
FTR I make a practice of never involving manager because that is chickenshit tattling, unless I have exhausted all other options. I didn’t just send links (he would not have read them), I wrote long and detailed explanations, which he either ignored or responded to with pastes that had nothing to do with what I’d sent. I put up with a lot.
I mentioned I am usually the back-end developer albeit in the .NET/C# stack, but I am accustomed to dealing with the front-end people and assuring that all details were understood, and I usually wrote brief documents. One of my many beefs with scragile is it dismissal of documentation. listening and speaking aren’t good enough.
As was amply shown by L forgetting the name of my branch, seconds after speaking it several time. I had to mute at that point and I nearly left the call. Th guy was hopeless. He’ll drift from one job to another, never learning or improving but going through the motions of screen sharing and conference calls for trivial matters and putting on a show of being professional
Anyway this project had no spec, which usually means I turn it down, had no QA, had a daily status report on Zoom instead of the email we managed to get by with for 20-odd years. The managers were not former developers but they seemed to know a lot about crypto, on reflection I think they were working from requirements dictated by their client.