How to Write Garbage Code

🧠 Core Idea: Reduce Cognitive Load

Linus Torvalds harshly criticized a Meta engineer’s pull request, calling out a helper function make_u32_from_two_u16() as “useless garbage.” His main argument? It obscures intent and increases cognitive load.

🔍 Key Takeaways:

• Explicit > Abstract: Writing (a << 16) + b is clearer than using a helper function that hides logic.

• PRY > DRY: “Please Repeat Yourself” can be better than “Don’t Repeat Yourself” when duplication reduces mental overhead.

• Micro-Context Switches Matter: Jumping across files/functions adds cognitive cost for humans and LLMs alike.

• Chunking Limits: Human brains can only hold 4–7 “chunks” at a time—each abstraction eats into that.

• Locality of Reference: Keeping related code together improves readability and iteration speed.

• Refactorability > Premature Optimization: With modern IDEs and LLMs, duplication is cheap and easy to clean up later.

⚠️ Tone Matters

While Linus’s technical point is valid, the article cautions against emulating his aggressive tone. Constructive feedback fosters better collaboration.