A real-time overlay for a plane-spotting livestream
Broadcast graphics one person drives from a phone, built so the screen can never go blank on air. Delivered and accepted.
One operator drives the overlay from a phone. The overlay draws the last good state it saw, so a dropped connection redraws instantly instead of showing an empty frame.
The operator writes to a single source of truth. The overlay renders whatever state it last saw, as a pure function of that state. On reconnect the current state replays at once, so the screen stays consistent by construction.
Delivered and accepted, with a requirements-to-evidence matrix handed over.