SF / 002Door and check-in application
ScannerSync
Guest check-in that keeps working when the signal doesn’t.
A queue at the door does not care that the venue’s uplink went down. ScannerSync is built on the assumption that it will.
- 0
- Bars of signal required
- 1:1
- Idempotent scan to check-in
- Stores
- App Store and Google Play
- 4
- Angular · Capacitor · ML Kit · IndexedDB
What it does
ScannerSync, in detail.
The door app for the EventSync ecosystem. It holds the guest list on the device, scans against it with no connection at all, and drains its queue in order when the signal returns.
- 01
The guest list lives on the phone
Before doors open the event is pulled down in full. From that point the scan is a local lookup, so it answers as fast as the camera can read the code.
Camera QR scanning through ML Kit Per-seat check-in for reserved events Partial check-in for a group booking arriving in twos
- 02
Wrong is recoverable, double is not
A door app that checks the same guest in twice is worse than one that is briefly offline, so the queue is built to make that impossible.
Undo a check-in any time before it syncs Every queued action carries an idempotency key The queue drains in order, so the server sees the night as it happened
- 03
The awkward cases are handled on purpose
Real doors produce codes nobody planned for. The app admits the guest and flags the decision rather than holding up the queue.
Unrecognised codes are admitted and marked for the server to judge Seats moved off the live chart without leaving the door A visible queue, so staff can see what has not yet reached the server
Gallery
ScannerSync, in production.
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