FastAPI Validation Deep Dive: Mastering Pydantic vs Manual Logic for 2025

As we move into 2026, writing robust APIs requires moving beyond basic syntax to understand how underlying validation frameworks actually influence application performance. This guide explores whether...

📺 Watch here: https://www.youtube.com/watch?v=0IZqA2zJuj0

##FastAPI ##Pydantic ##Python ##API

https://blog.dataengineerthings.org/why-data-engineers-should-care-about-pydantic-821eb0f6c892

#DataEngineering #Pydantic

Python devs, is this familiar: Your team writes beautiful snake_case code, but every external API wants camelCase.

You could:
- Pollute your codebase with non-Pythonic naming
- Write manual conversion layers
- Live with the friction

Or you could use Pydantic's field aliases to solve this once and for all.

New guide: How to handle non-Pythonic naming conventions seamlessly 👇
https://link.testdouble.com/e357d1

#Python #Pydantic

TIL #PyAI on March 10th 2026 (just missed it). Small event, focused on unglamourous AI in production, some of the speakers were practitioners I know and respect. The description reminds me a bit of #NormConf !

https://pyai.events/

- Talk videos will hopefully be released online soon
- Blogpost by @pamelafox, one of the speakers: https://blog.pamelafox.org/2026/03/learnings-from-pyai-conference.html
- Organisers plan to organize another one next year 👀

#llms #genai #pydantic

I used #Pydantic Evals to evaluate a bunch of agents today. After running an evaluation, I'd like to inspect the SpanTree for each evaluation case, e.g. to check which tools were called and debug my custom Evaluators. My current approach is a custom Evaluator that captures the tree as a side effect into a module-level variable.

Storing the trees in a global var is not great, so let's see if we can come up with a better solution: https://github.com/pydantic/pydantic-ai/issues/4758

#llms #evals #foss

Planning to make large behavioural changes to a (sometimes long-running) production-grade AI agent. Working with `pydantic-evals` today because I want to eval the agent before and after. So far it looks very similar to Langfuse datasets/runs for evalling, except that the data lives in your repository instead of in the Langfuse platform.

https://ai.pydantic.dev/evals/

#llms #pydantic #genai #agents #claude #langfuse

Hahaha, oh Pydantic...

> Unlike unit tests, evals are an emerging art/science. Anyone who claims to know exactly how your evals should be defined can safely be ignored.

Source: https://ai.pydantic.dev/evals/

#pydantic #evals #llms #genai

RE: https://mastodon.social/@lobsters/116241885772634780

Oxyde looks really cool. I work with Pydantic a lot, but have missed having the Django ORM. Oxyde appears to bring a Django ORM-like experience to Pydantic, and I'm here for it.

#Pydantic #Python #Django

Oxyde – Pydantic-native async ORM with a Rust core

https://github.com/mr-fatalyst/oxyde

#HackerNews #Oxyde #Pydantic #ORM #Rust #async #Python #developer #tools