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-# 015-coffee_machine
+# Coffee Machine
 
+A console game from Udemy's *100 Days of Code: The Complete Python Pro Bootcamp*
+(day 15). A virtual coffee machine serves espresso, latte and cappuccino. Pay with
+US coins (quarters, dimes, nickels and pennies). The machine checks its water, milk
+and coffee before it serves, refunds you if you pay too little and gives change if
+you pay too much.
+
+```
+What would you like? (espresso/latte/cappuccino): latte
+Please insert coins.
+How many quarters?: 10
+How many dimes?: 0
+How many nickels?: 0
+How many pennies?: 0
+Here is your latte. Enjoy!
+```
+
+- Python 3.13 or newer, no runtime dependencies.
+- Type `report` to see the water, milk, coffee and money in the machine, and `off`
+  to switch the machine off.
+- The function names follow the assignment: `is_resource_sufficient`,
+  `process_coins`, `is_transaction_successful`, `make_coffee`.
+- Money is counted in whole cents inside the program, so change is never off by a
+  rounding error.
+
+## Requirements
+
+- [Python](https://www.python.org/downloads/) 3.13 or newer
+- Optional: [Doxygen](https://www.doxygen.nl/) to build the source documentation
+
+## Set up
+
+Create a local virtual environment in `.venv`, activate it, and upgrade `pip`.
+
+Windows (PowerShell):
+
+```powershell
+python -m venv .venv
+.venv\Scripts\Activate.ps1
+python -m pip install --upgrade pip
+```
+
+Windows (Git Bash), Linux and macOS:
+
+```bash
+python -m venv .venv
+source .venv/Scripts/activate   # Linux/macOS: source .venv/bin/activate
+python -m pip install --upgrade pip
+```
+
+The machine itself needs nothing more. To run the tests and the code checks, install
+the development tools:
+
+```bash
+python -m pip install -e ".[dev]"
+```
+
+## Run the coffee machine
+
+```bash
+python -m coffee_machine
+```
+
+Type `espresso`, `latte` or `cappuccino` and press Enter, then enter the coins.
+Type `report` for the machine's resources, or `off` to quit.
+
+## Run the tests
+
+```bash
+python -m pytest
+```
+
+Check the code style and types:
+
+```bash
+python -m ruff check src tests
+python -m ruff format --check src tests
+python -m mypy src tests
+```
+
+## Build the source documentation
+
+The source uses Doxygen comments. The HTML output goes to `docs/doxygen/html`.
+
+```bash
+doxygen Doxyfile
+```
+
+## Project layout
+
+| Path | Content |
+| --- | --- |
+| `src/coffee_machine/` | The machine: `main.py` (the loop), `constants.py` (menu, coins, starting resources) |
+| `tests/` | pytest tests |
+| `docs/` | Planning and review documents (business case, plan, milestones) |
+| `pyproject.toml` | Project configuration |
+| `Doxyfile` | Doxygen configuration |
+
+## License
+
+GNU Affero General Public License v3.0. See [LICENSE](LICENSE).