Nexus Android

Native Android IM client for Nexus, built with Jetpack Compose + Kotlin.

The app talks to Nexus backend services through generated Connect-Kotlin clients. Room is the local source of truth for conversations, messages, contacts, groups, agents, and media metadata; DataStore holds non-sensitive preferences, and Android Keystore protects credentials.

Requirements

• Android Studio with Android Gradle Plugin 9.3 support
• JDK 21 (pinned by .java-version; AGP requires at least JDK 17)
• Android SDK 36 and Build Tools 36.0.0
• buf CLI for protobuf generation

Commands

./gradlew generateProtocol
./gradlew assembleDebug
./gradlew test
./gradlew lint

Use task doctor to validate the local toolchain, task verify for the full quality gate, and task run-debug to build and launch the app on a connected device or the nexus_test AVD. Protocol generation uses pinned local generator artifacts; Nexus schemas are never sent to a remote code-generation service.

Architecture

• UI: Jetpack Compose + Material 3
• DI: Hilt
• Navigation: Compose Navigation
• Protocol: Protobuf + Connect-Kotlin generated from ../nexus-proto/proto
• Network: Connect RPC over OkHttp + WebSocket gateway
• Storage: Room + DataStore + Android Keystore
• Background reliability: WorkManager send queue and bounded sync recovery
• Push: optional Firebase Messaging (FID registration, data-only notifications, sync wake-up, deduplication, and deep-link routing)

Modules

Module	Purpose
app	Android application, UI, DI, network wrappers, sync, and local storage
protocol	Generated protobuf messages and Connect-Kotlin clients