From Boring Object-Oriented to INSANE Functional Code | Issue #13


Hi there,

Ever wondered whether you should go functional or stick with object-oriented programming? Today I’ll dive into the pros and cons of both and show you how to blend them for the best of both worlds! 🔥

In this week’s video, I refactor some tricky code with surprising results, exploring the eternal debate of functional versus object-oriented programming. I’ll show you a fun word puzzle generator powered by Python and AI and explain why it’s called a “Philippine” puzzle—it involves almonds, believe it or not! 🥜

Learn how moving methods out of classes can simplify your code, discover the power of function composition and closures, and learn to avoid the dreaded “God class” for cleaner design. 🤓

Enjoy the video and happy coding!

Cheers,

Arjan

# News

Python Metaclasses

This week’s blog dives into the world of metaclasses in Python! 🐍 Learn how metaclasses act as blueprints for defining classes, enabling the customization of class behavior, enforcing coding standards, and more.

Explore practical examples and discover built-in metaclasses like type, ABCMeta, and EnumMeta from Python’s standard library. 🛠️

The article will help you understand when and why to use this powerful feature in your projects, including specific use cases and scenarios where metaclasses can significantly enhance your code. 💡 Click here to read the full blog.

Why Facebook doesn’t use Git

Greg Foster recently published an interesting blog post on why Facebook chose Mercurial over Git for its version control system. 🖥️

He dives into Facebook’s need for better performance and extensibility and how Mercurial’s architecture and community support led to this pivotal decision.

If you are a tech enthusiast interested in the history and evolution of source control tools, click here to read the full post.

# Community

Having trouble scaling your FastAPI service?

Recently, a member of our Discord community asked for help to boost the performance of their FastAPI service. This sparked an engaging discussion with valuable insights and practical advice from several of our community members.

Join our Discord server to read the full thread on optimizing FastAPI for handling concurrent requests, improving performance with async routes, offloading heavy tasks, and more. 🌟


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.

🪄 Learntail

My team and I created an AI quiz generator designed to accelerate your learning, called Learntail. You can try it for free or unlock even more capabilities and features with the monthly subscription. Take a look here.

Unsubscribe | Send by ArjanCodes

Wolvenplein 25, Utrecht, UT 3512 CK

The Friday Loop

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.

Read more from The Friday Loop

Code can be correct and still be unpleasant to read. A lot of software design isn’t about what the code does but about how clearly it communicates the sequence of ideas behind it. In this week’s video, I explore the Fluent Interface pattern by refactoring a small animation engine in Python. I start with a clunky but functional API, then gradually reshape it until defining an animation reads almost like a sentence: move, rotate, scale, fade. Enjoy this deep dive into API design, readability,...

Have you ever looked at a Python script and thought: “Why is this slow? The logic is trivial.” Very often, the problem isn’t what your code does, but how often it does expensive work. In this week’s video, I start with a deliberately inefficient example: parsing a large CSV file multiple times. From there, I use it as a vehicle to introduce 10 powerful Python features that many developers either don’t know about or don’t know when to apply. I look at things like: • caching expensive...

I almost didn’t publish this week’s video. It’s about the Specification design pattern, and if I’m honest, the final version of the code scared me a little. It’s complex, abstract, and in many cases… absolutely overengineered. But there’s a reason I still decided to share it. In the video, I explore how the Specification pattern tackles a very real problem: business rules duplicated across different parts of a system, slowly drifting apart and becoming harder to change safely. Is this...