This is the code for a very simple banking system. The system contains only one code file (app.py) with an command line interface to donate money from one account to another or withdraw money from one account. We also have some predefined bank accounts, that can interact with the system and apply these two use cases.

The system only has one main function. However, in future we plan to add new use cases (e.g., loan), change the data storage (e.g., from sqlite to postgresql) or add another interface for the system (e.g., web api)

We want to be independent from any technology and third-party frameworks. In the end you should have a onion architecture-like structure with packages for infrastructure, application and domain. Keep in mind that the domain model and application should not have any external dependencies and all dependencies should be directed inwards.

1. Install Python (>= 3.9)
2. Create a virtual environment
   python -m venv .venv
3. Activate the virtual environment
   source .venv/bin/activate (Linux) or .venv/Scripts/activate (Windows)
4. Install all requirements
   pip install -r requirements.txt

You can run the system by executing python app.py <arguments>.

To get all available commands you can execute python app.py --help.