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The Friday Loop

Coupling 101: Design Choices That Make or Break Your Code | Issue #47

Published 7 months ago • 2 min read

Hi there,

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You’ve probably heard the phrase: “Coupling is bad.” But what if I told you that coupling is actually necessary? The real issue isn’t that your code has coupling—it’s that some types of coupling are worse than others. 🚨
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In this week’s video, I dive into three real-world examples of bad coupling and show you how to refactor them into better designs. We’ll tackle:
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  • Global coupling – Why global variables cause headaches and how to avoid them
  • Content coupling – When modules dig too deep into each other’s business
  • Stamp coupling – The sneaky way dependencies make your code harder to maintain
    ​

Plus, I’ll explain why AI struggles to fix these problems for you (spoiler: design is more than just code generation). 🤖❌

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Happy coding and enjoy the video!

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Cheers,

Arjan

# News

Python’s GIL: A Step Closer to Removal? 🐍

Big news in the Python world: the Global Interpreter Lock (GIL) might finally be on its way out! LWN’s latest article dives into PEP 703, which proposes making Python truly multi-threaded. No more GIL bottleneck—just faster, more efficient concurrency. ⚡

The catch? It’s a massive change with big implications for compatibility and performance. Curious how this could reshape Python development? 🧐 Read more here.

Duck Typing in Python: Type Less, Do More!

“If it walks like a duck and quacks like a duck…” you know the rest! 🦆 Python’s duck typing lets you write flexible, dynamic code without worrying about strict types. But when should you embrace it, and when does it become a maintenance nightmare? 🤔

Real Python’s recent course dives into duck typing, showing you how to balance flexibility and safety in your code. A must-watch for Pythonistas! 🐍💡Check it out here.

# Community

Ever used a decorator and noticed it messes with your function’s signature or docstring? 🤯 One of our Discord members ran into this exact issue when trying to preserve function metadata while decorating a method.

🛠️ What went wrong?

  • The function’s signature disappeared from tooltips in the IDE.
  • The docstring wasn’t showing as expected.
  • Even using @wraps didn’t fully resolve the issue.

👀 What’s causing it?

After some deep debugging (and a few rabbit holes 🐇), the community discovered a sneaky interaction between type hints and decorators. A small change made all the difference!

Want to know the fix? Curious if this might be affecting your decorators too? Join the discussion on Discord and see the full breakdown! 🚀

Do you enjoy my content on YouTube and would you like to dive in deeper? Check out my online courses below. They've helped thousands of developers take the next step in their careers.

🚀 The Mindset Online Course Series

The goal of this series is to help junior developers grow their skills to become senior developers faster.

💥 Other Courses

💡 If you’re part of a development team at a company, I offer special packages for companies that give your team the tools to consistently write high-quality code and dramatically increase your team's productivity.

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The Friday Loop

by ArjanCodes

Every Friday, you'll get a recap of the most important and exciting Python and coding news. The Friday Loop also keeps everyone posted on new ArjanCodes courses and any limited offers coming up.

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