770ab7ff82
### Context Profiling on an iPhone 12 mini (Profile build, real community) showed `RelaySessionNotifier._postForEvents` producing contiguous main-isolate busy runs with p90 110 ms and max 124 ms (27 runs of 50 ms or longer). Stacks were dominated by `jsonDecode` of `response.body`, with `NostrEvent.fromJson` smaller. The whole HTTP response decode ran on the UI isolate: gzip inflate (done by `dart:io`), the UTF-8 decode behind `response.body`, JSON parsing, and event parsing. ### What changes - Successful `/query` and `/profiles/search` responses (the only two callers of `_postForEvents`) are now decoded in a single `Isolate.run` from `response.bodyBytes`: inflate, UTF-8, JSON, validation, `NostrEvent.fromJson`. The parsed events come back by ownership transfer (`Isolate.exit`), not a copy. - Gzip: the query transport now sends `Accept-Encoding: gzip` and sets `autoUncompress = false`, so compressed bodies reach the isolate still compressed. Whether bytes are gzip is decided by the gzip magic bytes, so a transport that already inflated (or an injected test client) still works. Error bodies are inflated inline (small). - Unchanged: `FormatException` messages, the malformed-event wrapping, `RelayException.body`, and the rate-limit gate reading the error body. - Fencing (Review-Proven Rule 2): the `_disposed` / `_ageRestricted` / `_contextGeneration` check still runs before the decode and now runs again after it. If the session retires during the decode, the query reports `StateError` even when the decode itself failed, matching the old ordering where a retired session never decoded. ### Design notes - `Isolate.run` per response instead of a long-lived worker: no lifecycle or disposal to manage, no idle isolate heap on a small phone, easy to fake in tests, and the same shape as `parseProfileEventBatch`. The main-isolate side of a spawn measured at microseconds, so there is no size threshold; small responses take the same path. - Event id and signature verification does not happen on these events on the main isolate today (nothing in the mobile app verifies queried events; NIP-OA verification in profile parsing is already in an isolate), so nothing was moved. - Other HTTP decode sites found and left alone: invite create/join, hosted join policy, BuilderLab account, media upload response, community icon lookup, dev push lease NIP-11, archived-agents. These decode small, rare responses (one small JSON object each), where an isolate adds complexity without a measurable gain. Media and avatar byte downloads do no JSON decoding. The mobile app has no `/count` caller. ### Validation Added tests (`relay_session_test.dart`, through the production `queryRelay` / `searchProfiles` path with the real isolate decoder): parsing with non-ASCII content; profile search; gzip success body and `Accept-Encoding`; gzip error body feeding the rate-limit gate and `RelayException.body`; malformed JSON; non-list body; non-object element; malformed event; invalid UTF-8; error status skips decoding; session disposed, age-restricted, or retired-before-decode while a decode is outstanding. The fencing tests are falsifiable: removing the post-decode check fails the disposed and age-restricted tests; removing the retired-wins-over-decode-error branch fails its test; removing the pre-decode check fails the never-decodes test. `FakeRelay` (test helper) now injects an inline decoder, because `fakeAsync` cannot deliver isolate results; it calls the same parse function. The default transport still honors `http.runWithClient`, which the hosted journey tests use to fake the network (`relay_http_query_client_test.dart`; fails without the fix). `just mobile-check` and `just mobile-test` pass. Host benchmark (AOT executable on an Apple silicon Mac, median of 25, copy of the parse logic, main-isolate stall measured with a 0.5 ms heartbeat timer): | Response | Main-isolate blocked before | after | | --- | --- | --- | | 500 events, ~630 KB | 2.4 ms | 0 ms (max gap 0.05 ms) | | 500 events, ~630 KB gzip | 3.2 ms | 0 ms (max gap 0.19 ms) | | 500 events with 50 20 KB avatars, ~1.6 MB | 5.1 ms | 0 ms (max gap 0.28 ms) | | 500 events, ~4.5 MB | 14.0 ms | 0 ms (max gap 0.27 ms) | | 500 events, ~4.5 MB (827 KB gzip) | 17.4 ms | 0 ms (max gap 0.35 ms) | Total latency is unchanged within noise (for example 14.5 ms to 14.9 ms). The host is much faster than the 12 mini, so absolute device savings should be several times larger. On the iPhone 12 mini (Profile builds of base and this branch, real community over the production relay, two runs per scenario; main-isolate stalls measured with a 4 ms heartbeat timer, since the wireless device tunnel has no VM service): | Scenario | Main-isolate `_postForEvents` time, base | this branch | Max stall, base | this branch | | --- | --- | --- | --- | --- | | Cold start + 60 s (~16k events, 7.8 MB gzip) | 282 to 295 ms (max 116 ms) | 0.01 ms | 147 to 150 ms | 100 to 102 ms | | Inbox + search (~7k events) | 122 to 123 ms (max 111 ms) | 0.01 ms | 138 to 142 ms | 97 to 99 ms | | Open 6 channels (558 events) | 5 to 6 ms | 0.01 ms | 88 ms | 86 to 87 ms | | Background 10 s + resume (~7k events) | 118 to 124 ms | 0.01 ms | n/a (suspension) | n/a | - The production relay serves gzip (about 4.4:1; the largest catch-up response is 3.15 MB on the wire, 13.9 MB inflated, 7k events). Inside the isolate that response takes 30 to 47 ms to inflate, 39 to 55 ms for UTF-8, 65 to 105 ms for `jsonDecode` and 7 to 32 ms for `NostrEvent.fromJson`. - Many 16 to 90 ms stalls remain on both builds; they come from other work (mostly markdown build and layout), not response decoding. - Home, channels, inbox, search, profile and a thread render the same on both builds. buzz-review-completed 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Signed-off-by: Tom Brow <tomb@block.xyz> Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>
Buzz Mobile
Flutter mobile client for Buzz.
See VISION_MOBILE.md for intended behavior and architecture.
Optional Builderlab login
BUZZ_AUTH_DOMAINS is a comma-separated build-time environment setting, passed
with Flutter's --dart-define (shell environment variables alone are not read):
flutter run --dart-define=BUZZ_AUTH_DOMAINS=communities.buzz.xyz,communities.public.builderlabstaging.xyz
Unset or empty means Builderlab features are disabled: no account login, community creation, backup/recovery UI, reconnect prompts, or background account restoration. QR/code pairing, community links and invites use Nostr-only entry. Saved account keys and sessions are retained for a later enabled build.
A nonempty list enables Builderlab features and requires account setup only for
matching domains. Those features need their backend endpoints. Normal relay key
authentication remains in place. BUZZ_BUILDERLAB_URL selects the backend; setting
it alone does not enable Builderlab features.
Entries match the domain itself and its subdomains, case-insensitively. Use DNS
names, not URLs or wildcards. The list does not add trusted account servers:
configured domains outside the supported Builderlab realm cannot use hosted
setup. BUZZ_BUILDERLAB_URL still selects the trusted account environment.
Hosted relay authentication
--dart-define=BUZZ_HOSTED_RELAY_AUTH=true enables Builderlab relay assertions
and reconnect sign-in only for BUZZ_AUTH_DOMAINS matches. It defaults off: configure backend assertion issuance
before enabling mobile authentication, and enable relay enforcement last.
Setup
Use the Flutter SDK pinned by the repository. Activate Hermit from the repo root before resolving packages or running any Flutter command:
cd /path/to/buzz
. ./bin/activate-hermit
./bin/just mobile-install
mobile-build-android intentionally builds with --no-pub. If an IDE or an
external Flutter SDK has touched mobile/.dart_tool, rerun mobile-install
with the pinned SDK before building so flutter_test, sky_engine, and the
engine all come from the same Flutter version.
iOS toolchain
Use Xcode 27.0 for iOS development and build validation on an Apple silicon Mac running macOS Tahoe 26.6 or later, as required by the Xcode 27 release notes. On Intel Macs or hosts that cannot meet those requirements, use a compatible Xcode 26 version, which remains supported. Activate the repository's pinned Flutter SDK with Hermit as described above.
When multiple Xcode versions are installed, select the intended version for
the command with DEVELOPER_DIR, for example:
DEVELOPER_DIR=/Applications/Xcode-27.0.0.app/Contents/Developer xcodebuild -version
Adjust the path to your installation. Keep the compiler and SDK from the same
Xcode installation. The pinned Flutter native-assets tooling can discover the
globally selected SDK even when DEVELOPER_DIR selects another compiler, so
use a build machine with a matching default Xcode when validating either
Xcode 26 or Xcode 27.
The native cryptography dependency is pinned upstream C source in
ios/BuzzPushKit/Sources/CSecp256k1; it requires no Swift build-plugin approval.
GitHub's mobile CI currently uses the Xcode default of its macos-latest
runner. The internal release toolchain is configured separately in
buzz-releases.
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 --dart-define=BUZZ_PUSH_GATEWAY_URL=https://push.example
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.dev.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'sAppOverrides.xcconfigis included after it, so app-specific overrides like a personalBUNDLE_IDENTIFIERfor 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 enable push in direct Xcode builds and Runner tests, supply a
BUZZ_PUSH_GATEWAY_URL build setting in the gitignored
mobile/ios/Flutter/AppOverrides.xcconfig; the build phase validates and
passes it through as a Flutter Dart define. Since // begins an xcconfig
comment, spell the origin as BUZZ_PUSH_GATEWAY_URL = https:/$()/push.example.
For an Android debug build that must remain installed alongside other Buzz worktree builds, set an explicit launcher name and package suffix when invoking the generator or a recipe that invokes it:
BUZZ_PUSH_GATEWAY_URL="https://push.example" \
BUZZ_ANDROID_DEBUG_APP_NAME="Buzz Huddles" \
BUZZ_ANDROID_DEBUG_ID_SUFFIX=".huddles_829c" \
./bin/just mobile-build-android
This example produces the debug-only package
xyz.block.buzz.mobile.huddles_829c with the launcher label Buzz Huddles.
The suffix must start with a dot followed by a lowercase letter and may contain
only lowercase letters, digits, and underscores. Release and profile builds
ignore these overrides and retain the production package and name.
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.
iOS push capability
Every iOS artifact builds and embeds the Notification Service Extension and
native push bridge. Runtime activation is fail-closed and scoped to the current
relay. After authenticated connectivity and a fully valid NIP-11 buzz-push-v1 push
descriptor, Buzz independently requests display permission and registers with
APNs. Display denial or request failure does not gate the device token, gateway
enrollment, or lease publication, so a later user opt-in can display pushes
without rebuilding transport authority. An absent, malformed, or unreachable
descriptor leaves push inactive without partial enrollment.
Mobile builds without a gateway origin succeed with push unavailable. To enable push, supply the gateway origin explicitly:
flutter build ios --dart-define=BUZZ_PUSH_GATEWAY_URL=https://push.example
flutter build apk --dart-define=BUZZ_PUSH_GATEWAY_URL=https://push.example
The iOS and Android build gates validate any supplied define, rejecting empty or malformed values. Release/profile builds require an HTTPS origin without an explicit port. An absent define disables permission requests, APNs registration, gateway enrollment, and lease publication; Settings shows push as unavailable. No production gateway is selected implicitly. Enrollment grants and crash-recovery journals are scoped to this origin. Push has not shipped to existing users, so there is no legacy-state or cross-gateway migration. Changing gateways requires fresh enrollment; old installations expire under their original gateway's lease policy. Current-gateway response loss is still retried from the exact journaled request.
Relay rollout remains an explicit deployment opt-in. Only deployments with
BUZZ_PUSH_ENABLED=true advertise the descriptor and process push. 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, override the identity and sandbox
environments in the gitignored mobile/ios/Flutter/AppOverrides.xcconfig:
BUNDLE_IDENTIFIER = com.example.buzz.mobile
BUZZ_DEVELOPMENT_TEAM = YOUR_TEAM_ID
BUZZ_IOS_PUSH_ENVIRONMENT = development
BUZZ_APP_ATTEST_ENVIRONMENT = development
BUZZ_PUSH_GATEWAY_URL = https:/$()/push.example
Use your personal bundle ID and team above. Provision both the parent and its
.NotificationService extension. Configure an isolated gateway with the matching
App Attest application ID, APNs topic and sandbox certificate. Development
attestation requires the explicit personal-dev-app-attest gateway build feature
and BUZZ_PUSH_APP_ATTEST_ENVIRONMENT=development; ordinary gateway builds accept
production attestation only. See docs/push-gateway-deployment.md.
Validate distributed builds separately using a signed release candidate and
its matching gateway configuration.
Parent app identifiers 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 distribution 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 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 --dart-define=BUZZ_PUSH_GATEWAY_URL=https://push.example
Or from the repo root: just mobile-check and just mobile-test.
When writing tests, favor a few journey tests that drive real user flows over many small logic tests. See Testing Conventions.
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 fileBUZZ_ANDROID_UPLOAD_KEYSTORE_PASSWORDBUZZ_ANDROID_UPLOAD_KEY_ALIASBUZZ_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:
Gridtokens for consistent spacing - Linting:
flutter_lints+riverpod_lintviacustom_lint - Feature isolation: No cross-feature imports except
shared/