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Aleksei Aleinikov
Aleksei Aleinikov

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🧠 Why Python Dictionaries Can Secretly Ruin Your Codebase (and What To Do Instead)

🧠 Why Python Dictionaries Can Secretly Ruin Your Codebase (and What To Do Instead)

TL;DR: Python dict is super convenient β€” until it silently turns your project into spaghetti code. Here's why, and what to use instead.

❗ The Problem
What starts as a simple use of dict can evolve into a maintenance nightmare:

  • No type safety.
  • Anyone can modify structure anywhere.
  • Debugging becomes guesswork.

If your project grows, uncontrolled use of dictionaries will slow you down, introduce hidden bugs, and kill readability.

πŸ” Real Example Inside

I break down:

  • Why dict is bad as internal data structure.
  • How to transition to dataclasses, Pydantic, or at least TypedDict.
  • Clear code examples (yes, real ones!) with refactors.
  • Pro tips on keeping your data models clean and predictable.

πŸ‘‰ Want to see full examples, Pydantic vs. dataclass comparison, and migration strategy?
Check out the full article here:
πŸ‘‰ Why dictionaries in Python can β€œbreak” your project and how to avoid it (Medium)

🧰 Tools Mentioned:

  1. @dataclass
  2. Pydantic
  3. TypedDict
  4. Type hints like Mapping[str, str]

Let’s be honest: you can use dictionaries β€” but only where they belong.

Structure your code like a pro.
πŸ—£ What’s your approach to handling JSON data in Python? Drop your thoughts below πŸ‘‡
Or share how you migrated off raw dictionaries β€” always curious to hear other devs' stories!
https://levelup.gitconnected.com/why-dictionaries-in-python-can-break-your-project-and-how-to-avoid-it-fad0143df87a
🐍 Follow me here or on Medium for deep Python dives, dev tips, and clean code strategies.

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