buzz/mobile

Buzz Mobile

Flutter mobile client for Buzz.

Setup

cd mobile
flutter pub get

Run

# From repo root (applies a worktree-isolated debug identity and starts/reuses Simulator):
just mobile-dev

# Direct (uses the app's configured community; apply worktree overrides first):
cd mobile && flutter run

Worktree-aware debug identity

Debug builds produced from a git worktree get a unique app identifier keyed to the worktree directory name (xyz.block.buzz.dogfood.mobile.<slug> on iOS, xyz.block.buzz.mobile.<slug> on Android) plus a display-only branch label in the app name (Buzz (my-branch), or a short SHA when the worktree is detached). Because the identifier follows the directory rather than the branch, one worktree keeps exactly one installed app — and its login state — across branch switches, and builds from multiple worktrees install side by side, mirroring the desktop dev experience. Release and profile builds always keep the production identity and name.

just mobile-dev and just mobile-build-android apply this automatically by running scripts/mobile-worktree-overrides.sh, which writes two gitignored files:

• mobile/ios/Flutter/WorktreeOverrides.xcconfig (included by Debug builds only; a developer's AppOverrides.xcconfig is included after it, so app-specific overrides like a personal BUNDLE_IDENTIFIER for device signing always win)
• mobile/android/worktree.properties (read by the debug build type only)

Android developers can keep a stable local test identity that takes precedence over the generated worktree values by creating the gitignored mobile/android/AppOverrides.properties:

appName=Buzz Pairing
applicationIdSuffix=.device_pairing_e2e1

These values are consumed by the debug build type only. The standard just mobile-build-android command can still be used; regenerating worktree.properties does not overwrite AppOverrides.properties. Release and profile builds keep the production Buzz name and application ID.

For direct Xcode / Android Studio / flutter run development, run ./scripts/mobile-worktree-overrides.sh from the repo root once per branch switch to refresh the display label (the install identity never changes); the persisted files are then picked up by any subsequent build. In the main checkout the script is a no-op that removes stale override files, restoring the plain Buzz identity.

To remove leftover worktree-suffixed installs from booted iOS simulators and connected Android emulators, run just mobile-clean (add --dry-run via ./scripts/mobile-worktree-clean.sh --dry-run to preview). Production installs are never touched.

Internal iOS push capability

iOS push is a compile/build capability and defaults off. A normal Debug, Profile, Release, or App Store build excludes the native push bridge sources, uses push-free Runner entitlements, and neither builds nor embeds the Notification Service Extension. Dart also compiles out permission requests, APNs registration, gateway enrollment/delegation, and relay lease behavior.

For an authorized internal dogfood build only, create the gitignored mobile/ios/Flutter/AppOverrides.xcconfig with this single include:

#include "PushEnabled.xcconfig"

The tracked overlay selects xyz.block.buzz.dogfood.mobile, production App Attest/APNs entitlements, the internal development team, the push-capable Runner entitlements, the native bridge, and the extension. CI may equivalently inject that same include into its ephemeral AppOverrides.xcconfig; it must not edit a tracked base configuration. Relay rollout is independent and remains off unless its deployment sets BUZZ_PUSH_ENABLED=true. See docs/push-gateway-deployment.md for the canonical gateway profile contract, manual physical-device proof, measurements, and rollback procedure.

For local physical-device development, enable the same capability while overriding the dogfood identity back to the normal mobile development identity and sandbox environments:

#include "PushEnabled.xcconfig"
BUNDLE_IDENTIFIER = xyz.block.buzz.mobile
BUZZ_DEVELOPMENT_TEAM = EYF346PHUG
BUZZ_IOS_PUSH_ENVIRONMENT = development
BUZZ_APP_ATTEST_ENVIRONMENT = development

This exercises the client, extension, relay, and gateway integration without requiring a dogfood development signing identity. It uses the canonical gateway's server-owned App Store profile configured for sandbox in the local development gateway; it does not validate the internally distributed dogfood artifact or enable the App Store profile in production. Validate dogfood APNs end to end by cutting an internal release, waiting for it to reach Mobile Releases/Comp Portal, and installing that signed artifact on a physical device.

Push-enabled parent app identifiers also require Apple's Communication Notifications capability and a regenerated app provisioning profile. The Notification Service Extension profile does not require that capability. Enable it on the personal development App ID for local rich-presentation validation. Enabling it on the Block dogfood and eventual App Store App IDs is a release follow-up and is not performed by this repository change. Without a matching parent profile, source and unit validation still work, but the push-enabled app cannot be signed for a physical device.

APNs and the gateway continue to carry only the constant opaque wake-up. The extension fetches the message from the scoped relay, verifies message, sender profile, and channel-metadata signatures, and uses a bounded App Group cache for names and app-rendered avatar thumbnails. It never fetches an avatar URL; missing, stale, or invalid enrichment falls back to the verified message with a short sender pubkey, community subtitle, and no image.

Checks

dart format --output=none --set-exit-if-changed .
flutter analyze
flutter test

Or from the repo root: just mobile-check and just mobile-test.

Android release signing

Android release builds fail unless all upload-key inputs are supplied through the environment:

• BUZZ_ANDROID_UPLOAD_KEYSTORE_PATH: path to a CI-vended keystore file
• BUZZ_ANDROID_UPLOAD_KEYSTORE_PASSWORD
• BUZZ_ANDROID_UPLOAD_KEY_ALIAS
• BUZZ_ANDROID_UPLOAD_KEY_PASSWORD

The keystore path must be absolute, and the keystore must remain outside the repository. Development and debug builds do not require these variables.

Release pipelines that sign through the central APK Signer service instead of a local upload keystore must set BUZZ_ANDROID_RELEASE_SIGNING=external. That mode produces an unsigned release bundle and refuses to run if any BUZZ_ANDROID_UPLOAD_* value is also set.

Architecture

lib/
├── main.dart              # Entry point, Riverpod bootstrap
├── app.dart               # MaterialApp with theme
├── shared/
│   └── theme/             # Catppuccin light/dark, spacing tokens, extensions
└── features/
    └── home/              # Placeholder home surface

• State management: Riverpod + Hooks (HookConsumerWidget)
• Theme: Catppuccin Latte (light) / Macchiato (dark) — matches desktop
• Spacing: Grid tokens for consistent spacing
• Linting: flutter_lints + riverpod_lint via custom_lint
• Feature isolation: No cross-feature imports except shared/