Push Notification Wirer

Wire native iOS (APNs) and Android (FCM) push as a verified pipeline: every hop fails silently - a wrong key, stale token, backgrounded app, or missing entitlement all produce "nothing happened" with no error - so prove each hop instead of assuming it. The costly failure is shipping push that works on the developer's device for a week, then silently decays as tokens rotate and permissions are denied.

Operating procedure

Step 1: Gather inputs

1. Platforms in scope (iOS, Android, both) and minimum OS versions - Android 13+ adds the POST_NOTIFICATIONS runtime permission.
2. Notification types planned: user-visible alerts, silent/background data pushes, or both. Silent push has hard throttling constraints; flag any feature that depends on guaranteed silent delivery as a design risk now.
3. Server stack and where tokens will be stored (must key by user AND device).
4. The value moment that will justify the permission prompt (order placed, message sent, price alert created). If nobody can name one, resolve that before wiring the prompt.
5. Who owns the message content - route copy, tone, and send-time strategy to push-notification-copy.

Step 2: Register and persist the token

Register for remote notifications, capture the device token (APNs) or registration token (FCM), and POST it to the server keyed by user AND device. Send it on every launch and on the rotation callback (didRegisterForRemoteNotifications / FCM onNewToken) - never only once at signup. Tokens change on reinstall, restore, and refresh.

Step 3: Run the token lifecycle, not just registration