A modern, full-stack expense splitting application built with Flask and React, designed to help friends and groups manage shared expenses with ease.

SplitFree simplifies expense management for groups by automatically calculating who owes whom and how much. Whether you're splitting restaurant bills, shared apartment expenses, or travel costs, SplitFree handles the complex calculations and keeps everyone informed about their financial obligations.

• 👥 Create Groups - Organize expenses with roommates, friends, or travel buddies
• � Invite Members - Send email invitations or share SPLIT-ABC123 codes
• 🔓 Public/Private Groups - Control group visibility and joining methods
• �💳 Add Expenses - Record shared costs and automatically split them equally
• 💰 Track Balances - See who owes what at a glance
• 📊 Settle Up - Record payments and keep balances updated
• 🔒 Stay Secure - JWT authentication keeps your data safe

• 🐍 Python - Programming language
• 🌶️ Flask - Web framework
• 🗄️ SQLAlchemy - Database ORM
• 🔐 JWT - Authentication
• 📚 Swagger - API documentation
• 🐳 Docker - Containerization

• ⚛️ React 18 - UI library
• 🎨 CSS3 - Styling
• 🌐 Axios - HTTP client
• 🛣️ React Router - Navigation

• 💾 SQLite - Development database
• 🐘 PostgreSQL - Production ready

• Equal splits only (no custom percentages)
• No expense categories
• Manual payment recording

• 📊 Custom split ratios
• 🏷️ Expense categories
• 📸 Receipt photos
• 🔔 Push notifications

• Python 3.8+
• Node.js 14+
• npm or yarn

1. Clone the repository

   git clone <repository-url>
   cd splitwise

2. Create and activate virtual environment

   python -m venv .venv
   .venv\Scripts\activate  # Windows
   # or
   source .venv/bin/activate  # Linux/Mac

3. Install Python dependencies

   pip install -r requirements.txt

4. Set up environment variables (optional)

   # Create .env file for custom configurations
   echo "JWT_SECRET_KEY=your-secret-key" > .env

5. Initialize database

   flask db upgrade

6. Start the backend server

   python app.py

   Backend will run on http://localhost:5000

1. Navigate to frontend directory

   cd frontend

2. Install dependencies

   npm install

3. Start the development server

   npm start

   Frontend will run on http://localhost:3000

1. Start the backend server (python app.py)
2. Start the frontend server (cd frontend && npm start)
3. Open http://localhost:3000 in your browser
4. Register a new account or login
5. Create groups and start splitting expenses!

• POST /register - User registration
• POST /login - User login
• POST /logout - User logout
• POST /refresh - Refresh JWT token

• GET /group - Get user's groups
• POST /group - Create new group
• GET /group/{id} - Get group details
• DELETE /group/{id} - Delete group
• POST /group/{id}/user - Add user to group
• DELETE /group/{id}/user/{user_id} - Remove user from group

• GET /group/{id}/expense - Get group expenses
• POST /group/{id}/expense - Create new expense
• GET /group/{id}/expense/{expense_id} - Get expense details
• DELETE /group/{id}/expense/{expense_id} - Delete expense

• GET /user - Search users
• GET /user/{id} - Get user details

• JWT-based authentication with refresh tokens
• Authorization checks for all group/expense operations
• Users can only access groups they are members of
• Password hashing with secure algorithms
• Protected API endpoints with role-based access

splitwise/
├── app.py                 # Flask application entry point
├── db.py                  # Database configuration
├── requirements.txt       # Python dependencies
├── migrations/           # Database migration files
├── models/              # SQLAlchemy models
│   ├── user.py
│   ├── group.py
│   ├── expense.py
│   └── ...
├── resources/           # API route handlers
│   ├── user.py
│   ├── group.py
│   ├── expense.py
│   └── ...
├── schemas.py           # Marshmallow schemas
└── frontend/           # React application
    ├── src/
    │   ├── components/    # Reusable UI components
    │   ├── pages/        # Page components
    │   ├── services/     # API service layer
    │   ├── contexts/     # React contexts
    │   ├── hooks/        # Custom hooks
    │   └── utils/        # Utility functions
    ├── public/           # Static assets
    └── package.json      # Frontend dependencies

python app.py              # Start development server
flask db migrate           # Create new migration
flask db upgrade           # Apply migrations

npm start                  # Start development server
npm run build             # Build for production
npm test                  # Run tests

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

This project is licensed under the MIT License.

For issues and questions, please open an issue on GitHub.