Design in docs/push-notifications.md. The short version: Apple and Google are unavoidable —
iOS suspends apps so only APNs can wake one, and Android only accepts pushes from FCM — but
Expo is not. Its push service is a relay in front of both and does not remove either
credential, so we talk to Apple and Google ourselves.
Both protocols were verified in Bun before designing around them: node:http2 works as a
client (APNs is HTTP/2-only), and ES256 signing produces the raw 64-byte r||s form Apple
requires rather than Node's default DER, which is silently rejected. No push library is
needed for either channel.
The load-bearing decision is the payload: a push is a doorbell, not a message. Apple and
Google see metadata regardless, so they must not also see content — a notification carries a
category and an id, never a subject, sender or error, and the app composes the visible text
locally and fetches the real thing over the tailnet on tap.
This commit is the registry: push_devices, holding native APNs/FCM tokens. environment is a
column because APNs sandbox and production are different hosts AND different token
namespaces — a debug-build token fails against production with a silent BadDeviceToken, so
guessing is not an option. Registration upserts on (token, bundle_id) because tokens rotate
and the app re-registers every launch. Failure counting prunes dead tokens; a hard rejection
deletes at once.
Nothing sensitive lands here: a token is useless without the APNs key or FCM service
account, both of which stay in the sidecar's env.
NOTE: `bun db:push` will fail until the telegram/whatsapp/discord rows are deleted from
server_integrations — the CHECK constraint added earlier refuses while they exist. That is
the enforcement working, not a problem to route around.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>