Biometric integration that survives the real world
The answer
Devices go offline, people punch twice, and night shifts cross midnight. The punch pipeline de-duplicates, pairs INs with OUTs, assigns a punch after midnight to the shift that started before it, and keeps the raw events forever so any judged day can be re-derived and explained. When a device is down for an hour, the punches arrive late and the affected days are re-evaluated — not lost.
