CNVRT

A fast, privacy-friendly converter for currencies and common units with full offline support

About

CNVRT is a Flutter-based conversion application designed for speed, privacy, and offline resilience. It provides near real-time currency exchange rates with local caching for offline use, along with common unit conversions. The app follows clean architecture principles with a domain/io/ui separation pattern and uses Riverpod for state management.

Key Features

Currency Conversion

Real-time exchange rates for global currencies
Offline mode with local caching
Automatic refresh (configurable)
Network resilience with fallback to cached data
Optional inflation adjustment

Unit Conversion

Temperature (°C, °F, K)
Distance (km, miles)
Speed (kph, mph)
Weight (kg, lbs)
Area (m², ft²)
Volume (L, gal)

User Experience

Multi-language support (English, Spanish, Italian, Korean, Chinese)
Light, dark, and system theme options
Adjustable decimal precision (0-8 places)
Drag-to-reorder currencies
Country flags display
Copy-to-clipboard functionality
Data persistence for preferences

Technology Stack

Component	Technology	Purpose
Framework	Flutter & Dart	Cross-platform UI development
State Management	Riverpod	Reactive state with code generation
Database	Drift	Type-safe SQLite with reactive queries
Routing	Fluro	Declarative navigation
Networking	Dio	HTTP client for API requests
DI	spot_di	Dependency injection with thread safety

Quick Start

Prerequisites

Flutter SDK ^3.8.1 (Install Flutter)
Android Studio with Android SDK (for Android development)
Xcode (for iOS development, macOS only)

Installation

# Clone the repository
git clone https://github.com/wesleybliss/cnvrt.git
cd cnvrt

# Verify Flutter installation
flutter doctor -v

# Install dependencies
flutter clean
flutter pub get

# Generate code (Riverpod providers, Drift database, etc.)
flutter pub run build_runner build --delete-conflicting-outputs

# Run the app
flutter run

Development Commands

# Clean and reinstall dependencies
flutter clean && flutter pub get

# Generate code (one-time)
flutter pub run build_runner build

# Watch for changes (continuous generation)
flutter pub run build_runner watch

# Run static analysis
flutter analyze

# Run tests
flutter test

# Build release APK
flutter build apk --release

Build Variants

CNVRT supports two build flavors to accommodate different distribution channels:

Feature	Standard	FOSS
Firebase Crashlytics	✅	❌
Google Services	✅	❌
Distribution	Play Store, App Store	F-Droid, GitHub
Privacy	Remote error reporting	Local logging only

Learn more about FOSS builds in the FOSS Builds documentation.

Documentation

Architecture

Learn about the technical architecture, code style guidelines, and project structure.

View Architecture →

Contributing

Guidelines for contributing to the project, including setup, workflow, and coding standards.

View Guide →

FOSS Builds

Documentation on building FOSS-compliant variants for F-Droid and other open-source stores.

View FOSS Docs →

Get Involved

CNVRT is open source and welcomes contributions! Whether you want to report a bug, suggest a feature, or contribute code, we'd love to hear from you.