gps-speedo/.planning/codebase/STACK.md

Technology Stack

Analysis Date: 2026-02-09

Languages

Primary:

• Dart 3.9.0+ - Flutter app logic, services, UI widgets
• Kotlin - Android native bridge and plugin implementations
• Swift - iOS native bridge (untested)

Secondary:

• XML - Android manifest and resource files
• YAML - Flutter configuration and package management
• XML/Plist - iOS configuration

Runtime

Environment:

• Flutter 3.24.0+ (SDK)
• Android Runtime (API 21+, configured via Gradle)
• iOS Runtime (optional, iOS 12.0+)

Package Manager:

• Pub (Dart package manager)
• Lockfile: pubspec.lock (present)
• Direct dependencies resolved from pub.dev

Frameworks

Core:

• Flutter 0.0.0 - UI framework and cross-platform mobile development
• Material Design 3 - Flutter Material Design components with useMaterial3: true

Testing:

• Flutter Test SDK - Unit and widget testing framework (included in Flutter SDK)
• flutter_lints 6.0.0 - Linting rules for code quality

Build/Dev:

• flutter_launcher_icons 0.14.4 - Icon generation for Android and iOS
• Gradle (Kotlin DSL) - Android build system configured in android/app/build.gradle.kts

Key Dependencies

Critical:

• geolocator 14.0.2 - GPS positioning and real-time location streaming with heading/speed data
  • Platform-specific implementations: geolocator_android, geolocator_apple, geolocator_linux, geolocator_web, geolocator_windows
  • Transitive: geolocator_platform_interface 4.2.6
• permission_handler 12.0.1 - Runtime permissions management (location, overlay window)
  • Platform-specific: permission_handler_android, permission_handler_apple, permission_handler_windows, permission_handler_html

Infrastructure:

• wakelock_plus 1.3.2 - Keeps device screen/CPU awake during GPS tracking
  • Transitive: wakelock_plus_platform_interface 1.2.3
• flutter_overlay_window 0.5.0 - System-level floating window overlay for GPS data display
  • Core overlay service: flutter.overlay.window.flutter_overlay_window.OverlayService
• bg_launcher 0.1.0 - Brings app to foreground from background or overlay state

Utilities:

• http 1.5.0 (transitive) - HTTP client library (included as dependency of other packages)
• package_info_plus 8.3.1 (transitive) - App version and package info
• uuid 4.5.1 (transitive) - UUID generation for identifiers
• meta 1.16.0 (transitive) - Dart language annotations

Development Utilities:

• archive 4.0.7 - For launcher icon generation
• image 4.5.4 - Image processing for icons
• json_annotation 4.9.0 - JSON serialization support

Configuration

Environment:

• No .env files or environment variable configuration detected
• Configuration is hardcoded in Dart code and managed through SharedPreferences during runtime
• Key runtime settings:
  • Speed units (km/h, mph, knots) stored in app state
  • Theme selection (dark/light) managed in state
  • Location service permissions checked at runtime

Build:

• Android build configuration: android/app/build.gradle.kts
  • Namespace: com.novoyuuparosk.speedo
  • Min SDK: Flutter default
  • Target SDK: Flutter default
  • Source/Target Compatibility: Java 11
  • JVM Target: Java 11 (Kotlin)
• iOS build configuration: ios/Runner/Info.plist
  • Bundle ID: $(PRODUCT_BUNDLE_IDENTIFIER)
  • Supported orientations: Portrait, Landscape (Left/Right), Portrait Upside Down (iPad)

Icon Configuration:

• flutter_launcher_icons configuration in pubspec.yaml
  • Source image: icon/speedo.png
  • Generates both Android and iOS icons with adaptive icon support
  • Adaptive foreground: icon/speedo.png

Fonts:

• Custom font: DIN1451Alt
  • Asset file: fonts/din1451alt.ttf
  • Used for speedometer display typography

Platform Requirements

Development:

• Flutter SDK 3.24.0 or later
• Dart 3.9.0 or later
• Android development environment with Gradle
• Kotlin compiler (for Android native code)
• Physical Android device or emulator with GPS simulation (recommended: physical device for accurate GPS)

Production:

• Android 5.0+ (API 21+) for primary platform
• iOS 12.0+ (secondary/untested platform)
• Foreground service capability (Android 12+)
• System alert window permission (for overlay functionality)
• Location services enabled on device
• Screen wake lock capability for continuous monitoring

Permissions & Capabilities:

• Runtime permissions:
  • ACCESS_FINE_LOCATION - High-precision GPS
  • ACCESS_COARSE_LOCATION - Network-based location fallback
  • ACCESS_BACKGROUND_LOCATION - Background location access (optional)
  • SYSTEM_ALERT_WINDOW - Floating overlay window
  • FOREGROUND_SERVICE - Background service requirement
  • FOREGROUND_SERVICE_SPECIAL_USE - Overlay service special use
  • WAKE_LOCK - Keep device awake
  • REQUEST_IGNORE_BATTERY_OPTIMIZATIONS - Battery optimization bypass

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Stack analysis: 2026-02-09