I too have made similar observations regarding pydantic and FastAPI.

I was evaluating various Python async http frameworks and landed on a similar stack:

- attrs/cattrs for models - starlette+uvicorn for HTTP/websocket - validation I’m still on the fence about. I’ll see how far I get with the built in validators offered by attrs. I use voluptuous at work and generally like the DX but it’s in maintenance mode.

This is purely personally preference, I’m sure devs using fastapi+pydantic are more productive in the long run. It almost feels like I’m hand rolling my own fastapi implementation but at the same time I don’t want to be too locked in to frameworks like that.

Ive been burnt by magic frameworks that do too much behind the scenes and there’s something nice about fully understanding what’s going on when you hand stitch libraries yourself.

Depending on how far in you are, starlite/litestar has good documentation and offers another "batteries included" framework. Performance wise it's about the same and the stack is about the same. Fastapi suffers from the "one solo dev in Nebraska" paradigm (check out open prs and old tickets). For me the main draw of litestar is the batteries + better docs + more active development with multiple developers vs most other python web frameworks.

+1 for litestar[1]. The higher bus-factor is nice, and I like that they're working to embrace a wider set of technologies than just pydantic. The framework currently lets you model objects using msgspec[2] (they actually use msgspec for all serialization), pydantic, or attrs[3], and the upcoming release adds some new mechanisms for handling additional types. I really appreciate the flexibility in modeling APIs; not everything fits well into a pydantic shaped box.

[1]: https://litestar.dev/

[2]: https://github.com/jcrist/msgspec

[3]: https://www.attrs.org/en/stable/