The 4 Elements of Simple Design
Simplicity in software design is essential for maintainability and scalability but challenging to achieve. The 4 Elements of Simple Design provide a framework for it.
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Now, let's dive into today's micro-topic!
In short
🌟 Simplicity in software design is essential for maintainability and scalability but challenging to achieve. The 4 Elements of Simple Design provide a framework: code must pass tests, minimize duplication, maximize clarity, and use fewer elements. These principles guide developers in creating cleaner, more effective systems.
🔍 Tests ensure functionality and enable safe refactoring. Starting with tests helps avoid unnecessary code and keeps development focused on meeting requirements.
✂️ Reducing duplication and maximizing clarity make code understandable and maintainable. Stripping unnecessary elements further enhances simplicity, aligning with long-term goals.
Simplicity is hard
Simplicity in design is not just a virtue—it’s a necessity for maintainable and scalable software. But simplicity is also hard to achieve. How do we achieve it in our codebase? First, we need to agree on a shared meaning for simplicity, especially when it comes to software design: we can use the 4 Elements of Simple Design to give simplicity a meaning.
1. Passes its Tests
Tests ensure your software behaves as expected. Writing tests first, as in TDD (Test-Driven Development), encourages writing only the code you need to make the tests pass. That's why this is the first rule. Test also allow for safe refactoring in order to be able to improve design.
2. Minimize Duplication
Duplication is one of the biggest code smells. Repeated logic or code often indicates deeper issues in the design. Removing duplication simplifies the codebase and makes it easier to maintain.
3. Maximize Clarity
Clear code communicates intent.
Use meaningful names.
Create correct and purposeful abstractions.
Strive for code that is so obvious it answers questions before they’re asked.
You should write the more obvious code possible, you should even question yourself "Do I really have to be this explicit?" and the answer is yes!
4. Has Less Elements
Once your code passes tests, eliminates duplication, and maximizes clarity, ask yourself: Can I achieve the same with less? Simplify further by reducing unnecessary elements or code. Less code means fewer bugs and less maintenance.
The order matters
These elements work best when applied in sequence:
Make it work (tests).
Make it DRY (remove duplication).
Make it clear (maximize clarity).
Make it lean (reduce elements).
The reason is that in this order you can enable the following rules with the previous one: you proof your code works as expected thanks to tests, and those tests also enable the refactoring you will need to remove duplication, make it cleaner and remove elements.
To deep dive into the 4 rules, you should check out the book Understanding the Four Rules of Simple Design by Corey Haines, a foundational resource for mastering these principles.
Until next time, happy coding! 🤓👩💻👨💻