Dry Principle

This one enforces DRY principles with some genuinely useful guard rails. The standout feature is the Rule of Three: it won't let you extract shared code until you have three instances, which prevents the classic mistake of premature abstraction. It includes iron laws that push back against over-DRYing, like keeping coincidentally similar code separate if it serves different purposes, and preferring readability over abstraction when the indirection gets too clever. The anti-patterns table is specific about when DRY fails, like coupling unrelated domains or making tests unreadable. It's opinionated about when not to apply DRY, which is more valuable than tools that just scream about duplication everywhere.