Practical Pydantic

Practical Pydantic

The Missing Guide to Data Validation in Python

About the Book

Unlock the full power of Python data validation with Pydantic — the library trusted by FastAPI, SQLModel, and modern Python projects worldwide.

Whether you’re building APIs, cleaning messy datasets, managing environment configurations, or structuring ML workflows, this book gives you the practical skills and deep understanding to write safer, cleaner, and more reliable Python code.

Inside, you’ll discover:

  • Foundations of Pydantic and runtime data validation.
  • Advanced techniques: custom validators, nested models, and performance tuning.
  • Real-world projects: integrating APIs, ETL pipelines, and environment settings.
  • A thorough comparison of alternatives like Marshmallow, attrs, dataclasses, TypedDict, and more.
  • Expert guidance on choosing the right tool for your project.

Packed with examples, exercises, and actionable advice, this ebook is perfect for Python developers, data engineers, FastAPI users, and anyone who wants to level up their code quality.

Stop guessing whether your data is safe — trust Pydantic, and write Python code with confidence.

About the Author

Nuno Bispo
Nuno Bispo

Nuno Bispo is a Senior Software Engineer with more than 15 years of experience in software development.

He has worked in various industries such as insurance, banking, and airlines, where he focused on building software using low-code platforms.

For the past years, Nuno has been improving his skills in Python and Django and has worked as a freelance consultant on many international projects and written several innovative articles on his blog.

Currently, Nuno works as an Integration Architect for a major multinational corporation.

He has a degree in Computer Engineering.

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