"That Depends"

Dependency injection framework for Python.

Starting a new project? Also consider modern-di, the newer DI framework from the same author with a smaller core and per-framework integration packages. that-depends remains fully supported — see Ecosystem below.

It is production-ready and gives you the following:

• Simple async-first DI framework with IOC-container.
• Python 3.10+ support.
• Full coverage by types annotations (mypy in strict mode, pyrefly).
• Inbuilt FastAPI, FastStream and LiteStar compatibility.
• Dependency context management with scopes.
• Overriding dependencies for tests.
• Injecting dependencies in functions and coroutines without wiring.
• Package with zero dependencies.

Installation

pip install that-depends

Ecosystem

that-depends is part of the modern-python family. If you're starting a new project, consider modern-di — the newer DI framework from the same author, with separate framework adapters:

• modern-di — core DI framework with scopes
• modern-di-fastapi, modern-di-litestar, modern-di-faststream, modern-di-typer, modern-di-pytest

that-depends remains actively maintained — see the migration guide if you want to move existing projects across.

📚 Documentation

📦 PyPi

📝 License