This PR implements MVP, iOS-only,
[NIP-PL](8d2d0ff5ad/docs/nips/NIP-PL.md)-compliant
push notifications.
A relay with `BUZZ_PUSH_ENABLED` will send a push notification for any
message that appears in the in-app Notifications tab.
## Enrollment flow
The first time the client first connects to a relay with
`BUZZ_PUSH_ENABLED`:
```mermaid
sequenceDiagram
autonumber
participant App as Buzz iOS app
participant iOS
participant Relay as Buzz relay
participant Attest as Apple App Attest
participant Gateway as Push gateway
App->>Relay: Fetch NIP-11 push capability
Relay-->>App: Push profile, current relay public key, and limits
par
App->>iOS: Request notification permission
iOS-->>App: Permission result
and
App->>iOS: Register for remote notifications
iOS-->>App: Device token
end
App->>Gateway: Request installation challenge
Gateway-->>App: Single-use challenge
App->>Attest: Attest installation transcript
Attest-->>App: Attestation proof
App->>Gateway: Enroll device token and proof
Gateway-->>App: Installation handle
App->>Gateway: Request delegation challenge
Gateway-->>App: Single-use challenge
App->>Attest: Assert relay-key delegation
Attest-->>App: Assertion
App->>Gateway: Create delegation
Gateway-->>App: Opaque endpoint grant
App->>Relay: Publish encrypted push lease and filters
Relay-->>App: Lease acknowledged
```
## Push-time flow
When a notification-eligible event is received by the relay:
```mermaid
%%{init: {
"sequence": {
"actorMargin": 20,
"width": 110,
"messageMargin": 18,
"diagramMarginX": 8,
"wrap": true
}
}}%%
sequenceDiagram
autonumber
participant Relay as Buzz relay
participant Gateway as Push gateway
participant APNs as Apple Push<br/>Notification service
participant iOS
participant NSE as Notification service<br/>extension
Relay->>Gateway: POST /v1/deliveries/apns<br/>opaque endpoint grant, request ID, expiry, NIP-98 authorization
Gateway->>APNs: POST /3/device/{device-token}<br/>topic, request ID, expiry, constant mutable-content payload
APNs-->>Gateway: 200 OK: request accepted
Gateway-->>Relay: 200 OK: accepted status
APNs-->>iOS: Notification: constant reconnect alert<br/>mutable-content = 1
iOS->>NSE: Invoke extension<br/>original notification content
NSE->>Relay: POST /query: subscription filters, limit 10<br/>NIP-98 authorization
Relay-->>NSE: 200 OK: signed Nostr events<br/>kinds 9, 40002, 45001, or 45003
NSE->>iOS: Complete notification: title, body, subtitle<br/>thread ID, exact-message target
```
relay → push gateway → APNs -> NSE -> Notification Center
## Known limitations
The APNs wake payload is intentionally constant and opaque: it contains
no originating community or message identifier, in keeping with the
implemented NIP-PL privacy design.
The Notification Service Extension must therefore reconnect to the relay
and resolve eligible messages after each wake. Around overlapping wakes,
timing boundaries, or resolution windows, notification presentation may
occasionally omit an expected message or display a message more than
once.
This best-effort behavior is deliberately accepted for the current
implementation and will be measured during the internal rollout to
determine whether the user experience is acceptable before any broader
deployment; the implementation does not claim exactly-once presentation.
## Validation
Live end-to-end hardware validation used an internal remotely hosted
development relay and push gateway, the APNs sandbox, and a physical
iPhone 12 mini:
- A second real Buzz client published a uniquely marked message through
the hosted relay.
- The relay matched the message and sent the constant opaque wake
through the hosted gateway. The gateway made an actual APNs request; no
`simctl push` or simulated notification was used.
- The iPhone received the notification on its lock screen. The
Notification Service Extension reconnected to the relay, fetched the
event, verified its ID and signature, and replaced the placeholder
content with the real notification title and body.
- After the app populated its shared presentation cache, a final marked
notification visibly showed the sender display name, sender avatar, and
hashtag-prefixed channel name.
- Tapping a lock-screen notification opened Buzz and exercised the
notification-response path and navigated to the corresponding message.
Final validation with a dogfood-signed artifact and production App
Attest/APNs configuration remains a release step.
## Independent pre-reviews
- **First pass:**
[Carl](buzz://message?channel=18882f4c-289f-41db-942f-81f6f8066da1&id=74ab9a93bb227f3e762568f1cf9fee66d7495b0edc3918735ff787238b9cc585)
found missing transient retries, executor-key rotation suppression,
duplicate installation renewal, and an unauthenticated challenge write
amplifier. These were resolved by [retry-safe
bootstrap](https://github.com/block/buzz/pull/6269/changes/12c66ea62)
and [authenticated renewal plus a cross-replica
quota](https://github.com/block/buzz/pull/6269/changes/8e5ece0bd).
[sol-max](buzz://message?channel=ad83385f-8e9e-4461-9a35-c1bf2e208532&id=d26d53daa4684669e2ed354638241f13f36c3a97027fe8b4dd738aff09038962)
found delegation generation burning and an edited applied migration,
resolved by [exact-generation
revocation](https://github.com/block/buzz/pull/6269/changes/c26d2159d)
and a [forward-only
migration](https://github.com/block/buzz/pull/6269/changes/956c1d099).
[k3-max](buzz://message?channel=5e46055d-a766-4065-ae25-05d1e4aaa6b2&id=d43139138a0b15f806cbdbeeedd8f69d992cadf2e805876db6fdde6a34c7eda1)
found no blockers.
- **Exact-head re-review:**
[Carl](buzz://message?channel=18882f4c-289f-41db-942f-81f6f8066da1&id=a897721673459301b0cf26e8b85a1478d7ebbb56a4621f93d774c98d395b8f68),
[sol-max](buzz://message?channel=ad83385f-8e9e-4461-9a35-c1bf2e208532&id=fb2159f709ec68f74f7b21459acd76da0e8a7c5c0f3d469f99826b0cc2380849),
and
[k3-max](buzz://message?channel=5e46055d-a766-4065-ae25-05d1e4aaa6b2&id=2ce2842910435f562e9d9cc718595848f281b122c94605e523a4b964254b8bfb)
independently returned **NO BLOCKERS** at `7eb3a650b`; k3-max also
revalidated every remediation and the endpoint-specific App Attest
enrollment bound.
---------
Signed-off-by: Tom Brow <tomb@squareup.com>
Signed-off-by: Tom Brow <tomb@block.xyz>
Co-authored-by: Tom Brow <tomb@squareup.com>
Co-authored-by: Codex <noreply@openai.com>
Co-authored-by: Jordan Mecom <jm@squareup.com>
### What changed?
After a new mobile invite claim succeeds, Buzz now best-effort ensures
membership in the same public starter channels as desktop:
- `#general`
- `#welcome-everyone`
Missing starters use desktop's deterministic per-relay IDs and exact
public channel configuration, so concurrent mobile and desktop setup
converges safely. Setup failures do not invalidate or retry an already
successful invite claim, and failure for one starter does not block the
other.
The success sheet offers **Continue to #welcome-everyone** when that
channel is available. Mobile does not create the private `Welcome`
channel because it cannot provision the desktop Welcome agents that make
that channel useful.
This PR is stacked on #6145 because it deliberately reuses that PR's
open-channel directory and join behavior. Once #6145 merges, this PR can
be retargeted to `main` without changing its BUZZ-12 diff.
Fixes
[BUZZ-12](https://linear.app/squareup/issue/BUZZ-12/bug-community-appears-empty-after-using-invite-link-on-mobile).
### How is it tested?
- Desktop/mobile deterministic starter-ID parity coverage.
- Existing-channel join and missing-channel creation coverage.
- Duplicate-create convergence and per-channel failure isolation
coverage.
- Invite success remains successful when starter setup fails.
- Widget coverage for continuing directly into `#welcome-everyone`.
- Focused invite/deep-link tests: 23 passed.
- `just mobile-check`: passed.
- `just mobile-test`: 1,483 passed.
- Pre-push repository checks: passed.
---------
Signed-off-by: Tom Brow <tomb@block.xyz>
Co-authored-by: Codex <noreply@openai.com>
**Category:** new-feature
**User Impact:** Mobile users must confirm with Face ID, biometrics, or
their device passcode before sending their Buzz identity to Desktop.
**Problem:** A signed-in phone could send its full identity, including
the `nsec`, to a desktop without fresh local verification.
**Solution:** Require OS device authentication before opening the
identity-recovery scanner, retain that authorization only for the active
pairing session and short pairing window, and require fresh
authentication again if it expires before the identity payload is sent.
Normal app opening, identity import, and community removal remain
unchanged.
## Screencasts
| Enable Face ID | Use Face ID |
| --- | --- |
| 
| 
|
<details>
<summary>File changes</summary>
**Android and iOS integration**
- `mobile/android/app/build.gradle.kts` declares the AppCompat
dependency required by the biometric activity theme.
-
`mobile/android/app/src/main/kotlin/xyz/block/buzz/mobile/MainActivity.kt`
uses the activity type required by the system authentication prompt.
- `mobile/android/app/src/main/res/values/styles.xml` and
`mobile/android/app/src/main/res/values-night/styles.xml` use the
compatible launch theme.
- `mobile/ios/Podfile.lock` records the native local-authentication
dependency.
- `mobile/ios/Runner/Info.plist` explains why Buzz requests Face ID
access.
**Identity policy and pairing flow**
- `mobile/lib/shared/security/sensitive_action_authorizer.dart` wraps OS
authentication and maps platform errors to stable app-level outcomes.
- `mobile/lib/shared/community/community.dart` and
`mobile/lib/shared/community/community_storage.dart` persist the
sensitive-action policy.
- `mobile/lib/features/invites/invite_join_provider.dart` assigns the
explicit policy for invite-created communities.
- `mobile/lib/features/pairing/pairing_provider.dart` gates export,
binds grants to the active community/session, reauthenticates expired
grants, and clears grants on every terminal path.
- `mobile/lib/features/pairing/pairing_page.dart` lets users choose
biometric protection while importing an identity.
- `mobile/lib/features/settings/settings_page.dart` wires pairing into
settings.
- `mobile/lib/features/settings/settings_page/connection_section.dart`
authenticates before opening export recovery and bounds the
foreground-resume wait.
- `mobile/pubspec.yaml` and `mobile/pubspec.lock` add and lock
`local_auth`.
**Coverage**
- `mobile/test/shared/security/sensitive_action_authorizer_test.dart`
covers native result mapping, unsupported devices, and single-flight
behavior.
- `mobile/test/shared/community/community_test.dart` and
`mobile/test/shared/community/community_storage_test.dart` cover policy
defaults and persistence.
- `mobile/test/features/invites/invite_join_provider_test.dart` covers
the invite policy.
- `mobile/test/features/pairing/pairing_page_test.dart` covers import
protection controls.
- `mobile/test/features/pairing/pairing_provider_test.dart` covers
export/import authorization, stale/reset/concurrent guards, malformed
payload cleanup, and no-export failure paths.
- `mobile/test/features/settings/connection_section_test.dart` covers
the tap gate, lifecycle resume, and timeout behavior.
</details>
## Reproduction steps
1. Pair an identity into the mobile app.
2. Open Settings and choose “Send identity to desktop.”
3. Verify Face ID, biometrics, or the device passcode is required before
the recovery scanner opens.
4. Cancel device authentication and verify the scanner does not open and
no identity transfer begins.
5. Authenticate, scan a Desktop recovery code, confirm the SAS, and
verify the identity transfer completes.
## Validation
At `be5620f5f10aa6cc16e86a4f01f102f3d9aeef9b`:
- `cd mobile && ../bin/flutter analyze` — no issues
- `cd mobile && ../bin/flutter test` — 1,368 tests passed
- `cd mobile/android && JAVA_HOME=$(/usr/libexec/java_home -v 21)
./gradlew app:assembleDebug` — debug APK assembled successfully
---------
Signed-off-by: Taylor Ho <taylorkmho@gmail.com>
