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YAGNI
You aren’t gonna need it. Do not let the model build the abstraction nobody asked for.
What is YAGNI?
YAGNI is Extreme Programming’s brake: only what this slice needs. Plugin systems, theme engines, generic frameworks — not unless this slice uses them.
Why does YAGNI matter when vibe coding?
The model’s prior is “complete product.” Without YAGNI it builds settings, roles, and dark mode. In vibe coding YAGNI belongs in every prompt, not on a poster.
How do you do YAGNI?
Each turn, list three things not to do. That list matters more than the feature list. If the model opens a new abstraction, stop, delete, start the turn again.
How do you ask a model for YAGNI?
YAGNI. No notifications, no themes, no plugins, no roles. Only this slice: (verb). Delete extra files.
What goes wrong with YAGNI?
Using YAGNI to skip tests. Tests belong to this slice. What you skip is imaginary tomorrow.