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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My 2025 Tech Stack: What I’m Actually Using (and Why) | Issue #54
Published 9 months ago • 2 min read
Hi there,
What’s in my stack? Python, TypeScript… and one wooden robot. 🤖
You might not know this, but before ArjanCodes was a channel, it was a pile of ideas held together by duct tape and Google Docs. Now? We’ve got a full ecosystem: static websites on Astro, backend automations in Python, our own SDK, and a business portal for team licenses—all deployed with GitHub Actions and a sprinkle of serverless. ⚡
In this week’s video, I give you a behind-the-scenes tour of our real tech stack—no gatekeeping, just practical insight and a few jokes at my own expense. 😂
I hope you enjoy the video and happy coding!
Cheers,
Arjan
# News
🧠 Is Python Code Sensitive to CPU Caching?
Think CPU caching is only a concern for low-level languages? Lukas Atkinson challenges this notion in his insightful article.
Through a series of experiments, Lukas demonstrates that even in high-level languages like Python, memory access patterns can significantly impact performance. Specifically, he finds that random access patterns can be multiple times slower than sequential ones, especially when data sizes exceed CPU cache capacities. 💡
This suggests that being mindful of data access patterns can lead to more efficient Python code, even without the low-level control offered by languages like C++ or Rust. Interested? Click here to read more. 🧑💻
14 Advanced Python Features 🐍
Think you know Python inside out? Edward Li’s latest article, might surprise you. He delves into lesser-known aspects of Python that can elevate your coding game. 💡
From typing overloads and keyword-only arguments to structural pattern matching and metaclasses, this collection offers insights that go beyond the basics. Each feature is explained with clarity, making it accessible even if you’re not a Python guru. 📚
Whether you’re looking to write cleaner code, optimize performance, or simply explore Python’s depths, this article is a valuable resource. 👉 Read the full article.
# Community
I recently took ChatGPT’s new image generation feature for a spin—and of course, I had to see if it could recreate me. So I gave it a shot and shared the result on YouTube with one simple question: “Does this look like me?”
The responses from the community were absolutely gold—funny, thoughtful, and all over the map. From “Robert Downey Jr. vibes” and “just a Linux bit” to “JD Vance meets Ted Lasso,” people had opinions. Some said it nailed me, while others couldn’t imagine me ever looking that skeptical (or that grumpy 😅).
It’s been a fun reminder of how differently we see ourselves compared to how others—and now AI—perceive us. It also makes you wonder: what’s the next step in AI development? And am I about to be fully replaced by a synthetic version of myself? 🫣
Do you enjoy my content on YouTube and would you like to dive in deeper?
🚀 Check out my online courses
My courses have helped thousands of developers take the next step in their careers. Check out these courses to help grow your skills and become a senior developer:
The Software Architect Mindset - Learn the mindset that will allow you to effortlessly build and maintain scalable software systems. Become a software architect.
🔧 Need help with a complex codebase?
If your team is struggling with tech debt, unclear architecture, or cloud costs that keep creeping up, my team and I can help. We don’t just review, we get in and fix things. We’re only working with a few companies at a time to stay focused, so if it sounds like a fit:
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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