This project is a Django REST Framework-based API server that provides paginated, sorted, and filtered endpoints for managing transactions and wallets. The API follows the JSON:API specification using djangorestframework-jsonapi. The project is built with the best modern tools and libraries, e.g. uv and ruff.

• Wallet Management: Create, update and retrieve wallets with balances automatically calculated from transactions.
• Transaction Management: Create and retrieve transactions linked to wallets with strict constraints to prevent negative balances.
• Pagination, Sorting, and Filtering: Implemented for both Wallet and Transaction models.
• Strict Balance Constraint: Ensures a wallet’s balance never goes negative.
• Database Indexing: Optimized queries with indexes where necessary.
• Test Coverage: Comprehensive tests (just for the wallets app, which is sufficient for demo purposes).
• Linting: ruff check (run with pre-commit git hook).
• Formatting: ruff format and isort (run with pre-commit git hook).
• Testing: pytest tests (run with pre-commit git hook).

• Python: 3.13
• Django: 5.1
• Django REST Framework: 3.15
• PostgreSQL: 17
• djangorestframework-jsonapi: 7.1

• Docker and docker compose

docker compose up

docker compose run -it web bash -c 'DJANGO_SETTINGS_MODULE="config.settings" ./.venv/bin/pytest -s -v backend'