Hey there!

Summary of this email:

• The 4 rules of simple design (+ its course published on the Standard plan).
• Underperformance course published on ManagerPro.
• What we recorded last week.
• 5th edition of the AI for Programming Workshop now open.

Estimated reading time: 2 minutes.

🔢 The 4 rules of simple design

Years ago (back in the 1990s!), Kent Beck wrote 4 rules for achieving simple software design.

These rules have aged remarkably well over time, and in the AI era, they're even more valuable since they provide a solid foundation for writing code.

The rules are:

1️⃣ Reveals intention Code should clearly explain what it does and why, without needing to read comments or having to ask the person who wrote it (that person might be the you from a few months ago).

Variable, function, and class names should be expressive. The logic flow should be easy to follow.

2️⃣ Minimize the number of elements The fewer concepts, classes, functions, and modules there are, the easier it is to understand and maintain the system.

Be careful not to overdo this one, as it can lead to highly coupled code.

3️⃣ No duplication If the same knowledge or logic exists in more than one place, it's likely that modifying one component will require touching the others.

This rule needs to be interpreted carefully — otherwise it can be very problematic, as you might end up filling the codebase with premature abstractions.

There are various techniques for handling this, but the most recommended is the Rule of Three: Don't consider abstracting it until you've seen it duplicated 3 times.

4️⃣ Passes the tests Code must fulfill its purpose and work as expected.

• New code comes with tests.
• Refactored code doesn't break tests.
• If there's a bug, it gets tested and reproduced.

We've published the 4 Rules of Simple Design course on the Codely Pro Standard plan. 😊 We hope you enjoy it as much as we enjoyed recording it.

🗣️ Underperformance Course published on ManagerPro

Managing underperformance within a team is one of the toughest challenges for any manager.

This course guides you step by step through dramatized real-world cases, where you'll learn how to spot warning signs, avoid jumping to conclusions, and distinguish between individual, team, or organizational issues.

You'll see why the famous Performance Improvement Plans (PiPs) often fail, but also when they can make sense and what more effective alternatives you can apply.

Through practical examples, downloadable guides, and techniques like Needs Mapping, you'll learn how to open difficult conversations with empathy and design strategies that recover burned-out talent.

We'll soon be reducing the current discount on ManagerPro now that a new course has been published. So take advantage of it before that happens!

🎥 What we recorded last week

Last week was an intense week for Codely.

On Tuesday, we recorded an audit session that we absolutely loved. Unlike other audits we've done, this one doesn't focus on micro-design, but on macro-design.

They've got some serious legacy code (files with over 10,000 lines) and have come up with 2 proposals for how to get out of it. Our role is to evaluate those proposals and make our own. All with one mantra: we can't stop production.

So the goal is to keep shipping features while gradually getting rid of the legacy.

We'll publish it in a few weeks — we believe it's top-tier content and you're going to love it. 🙌

Also, on Thursday we ran the first edition of the AI for Programming Workshop for a company (Idealista). It was great and we got really positive feedback. If you'd like your company to host an exclusive edition, reach out to us at empresas@codely.com for more information.

✨ 5th edition of the AI for Programming Workshop now open

A thousand thanks once again. Seriously. We've sold out the 4th public edition of the AI for Programming Workshop. And after thinking it over, we've decided to open a fifth one for December.

We're putting a lot of care into the Workshop. Not just in the initial preparation, but in every edition we collect feedback to keep iterating on it. Plus, we keep updating it every time new technologies/tools come out.

Early spots come with a bigger discount than later ones, so grab yours as soon as you can!

And since you've made it this far in the newsletter, here's the joke of the week, which I know you were waiting for:

> This is a joke about recursion. You can only understand it if you read it again. 😂

Cheers!