Installation¶

pip install slowfw

That is the whole runtime. SlowAPI has zero required dependencies — no Pydantic, no Starlette, no anyio, no click. The import name is slowfw:

from slowfw import SlowAPI

On the name. slowapi on PyPI is an unrelated rate-limiting library for Starlette, which is why this project is not called that. slowfw is the distribution, the import and the command, so the two can share an environment without either noticing.

Supported versions¶


Python	3.10, 3.11, 3.12, 3.13
Operating systems	Linux, macOS, Windows
Implementations	CPython (PyPy is untested, not unsupported)

Python 3.10 is the floor because SlowAPI resolves X | Y annotations at runtime, which typing.get_type_hints only handles from 3.10 onwards.

Optional extras¶

Extras are opt-in on purpose: a dependency you did not ask for is a dependency you still have to patch.

pip install "slowfw[asgi]"       # uvicorn, for the ASGI path
pip install "slowfw[wsgi]"       # gunicorn, for the WSGI path
pip install "slowfw[templates]"  # jinja2, instead of the built-in engine
pip install "slowfw[pydantic]"   # pydantic models as DTOs
pip install "slowfw[all]"        # all of the above
pip install "slowfw[dev]"        # plus pytest, ruff, mypy

Nothing above changes how you write code. app.run() works with none of them installed, falling back to the standard library's wsgiref server (and telling you it did).

Extra	Enables
`asgi`	`uvicorn main:app`, and `app.run()` picking uvicorn
`wsgi`	`gunicorn main:app`, and `app.run()` picking gunicorn
`templates`	`app.configure_templates(..., engine="jinja2")`
`pydantic`	Pydantic models anywhere a dataclass DTO is accepted

Verify the install¶

python -m slowfw --version
python -c "import slowfw; print(slowfw.__version__)"

From source¶

git clone https://github.com/Somilg11/slowfw
cd slowfw
make install     # creates .venv and installs -e ".[dev,all]"
make check       # lint, types, and the full test suite

Scaffold a project¶

python -m slowfw new my-service
cd my-service
pip install -r requirements.txt
python -m slowfw run main:app --reload

The generated project has a health endpoint, a non-root Dockerfile, a .env example, and a test that runs on both protocols.