dry-principle

Dry Principle Skill

• Follow the DRY (Don't Repeat Yourself) Principle and Avoid Duplicating Code or Logic.
• Avoid writing the same code more than once. Instead, reuse your code using functions, classes, modules, libraries, or other abstractions.
• Modify code in one place if you need to change or update it.

Iron Laws

1. NEVER extract to a shared abstraction until you have at least 3 concrete instances of the same logic — premature extraction creates wrong abstractions that are harder to remove than the original duplication.
2. ALWAYS maintain a single source of truth for configuration values — the same constant or config value defined in two places will diverge and cause bugs.
3. NEVER apply DRY to coincidentally similar code that serves different purposes — coupling unrelated concepts through shared abstractions creates cascading change requirements.
4. ALWAYS prefer readability over DRY when the abstraction requires indirection that obscures what the code does — a small amount of duplication is often better than an obscure helper.
5. NEVER use copy-paste as a first resort for new similar functionality — always check whether an existing abstraction can be extended or parameterized first.

Anti-Patterns

Memory Protocol (MANDATORY)

Before starting:

cat .claude/context/memory/learnings.md

After completing: Record any new patterns or exceptions discovered.

ASSUME INTERRUPTION: Your context may reset. If it's not in memory, it didn't happen.