A full-stack expense splitting application that calculates the minimum number of transactions to settle group debts.
- JWT-based authentication (register & login)
- Create groups and invite members by email
- Add shared expenses with automatic equal splitting
- Debt simplification algorithm to minimize settlements
- RESTful API with Swagger documentation
| Layer | Technology |
|---|---|
| Frontend | Angular, PrimeNG, TypeScript |
| Backend | Spring Boot 3, Spring Security, JWT |
| Database | MySQL 8 |
| Build | Maven, npm |
split-settle/ ├── api/ # Spring Boot backend ├── split-settle/ # Angular frontend
- Java 17+
- MySQL 8+
- Maven 3.8+
# Create database
mysql -u root -p
CREATE DATABASE splitsettle;
# Run the backend
cd api
mvn clean install
mvn spring-boot:run
# API runs at http://localhost:8080
# Swagger UI at http://localhost:8080/swagger-ui.html- Node.js 18+
- npm 9+
cd split-settle
npm install
ng serve
# Runs at http://localhost:4200| Method | Endpoint | Description | Auth |
|---|---|---|---|
| POST | /api/auth/register | Register user | No |
| POST | /api/auth/login | Login | No |
| GET | /api/groups | Get my groups | Yes |
| POST | /api/groups | Create group | Yes |
| POST | /api/groups/{id}/members | Add member | Yes |
| POST | /api/expenses | Add expense | Yes |
| GET | /api/expenses/group/{id} | List expenses | Yes |
| GET | /api/settlements/{groupId} | Get settlements | Yes |
| POST | /api/settlements/settle | Settle up | Yes |
Instead of tracking every individual debt, the app calculates each user's net balance (paid - owed), then uses a greedy algorithm to match the largest debtor with the largest creditor — minimizing total transactions needed to settle a group.
- Passwords hashed with BCrypt
- Stateless JWT authentication
- CORS configured for local frontend dev
(Coming soon — frontend in progress)
Built by Dinesh Ravi