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name: code-philosophy description: Internal logic and data flow philosophy (The 5 Laws of Elegant Defense). Understand deeply to ensure code guides data naturally and prevents errors.

Internal Logic Philosophy: The 5 Laws of Elegant Defense

Role: Principal Engineer for all Internal Logic & Data Flow — applies to backend, React components, hooks, state management, and any code where functionality matters.

Philosophy: Elegant Simplicity — code should guide data so naturally that errors become impossible, keeping core logic flat, readable, and pristine.

The 5 Laws

1. The Law of the Early Exit (Guard Clauses)

• Concept: Indentation is the enemy of simplicity. Deep nesting hides bugs.
• Rule: Handle edge cases, nulls, and errors at the very top of functions.
• Practice: Use if (!valid) return; doWork(); instead of if (valid) { doWork(); }.

2. Make Illegal States Unrepresentable (Parse, Don't Validate)

• Concept: Don't check data repeatedly; structure it so it can't be wrong.
• Rule: Parse inputs at the boundary. Once data enters internal logic, it must be in trusted, typed state.
• Why: Removes defensive checks deep in algorithmic code, keeping core logic pristine.

3. The Law of Atomic Predictability

• Concept: A function must never surprise the caller.
• Rule: Functions should be "Pure" where possible. Same Input = Same Output. No hidden mutations.
• Defense: Avoid void functions that mutate global state. Return new data structures instead.

4. The Law of "Fail Fast, Fail Loud"

• Concept: Silent failures cause complexity later.
• Rule: If a state is invalid, halt immediately with a descriptive error. Do not try to "patch" bad data.
• Result: Keeps logic simple by never accounting for "half-broken" states.

5. The Law of Intentional Naming

• Concept: Comments are often a crutch for bad code.
• Rule: Variables and functions must be named so clearly that logic reads like an English sentence.
• Defense: isUserEligible is better than check(). The name itself guarantees the boolean logic.

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Adherence Checklist

Before completing your task, verify:

• Guard Clauses: Are all edge cases handled at the top with early returns?
• Parsed State: Is data parsed into trusted types at the boundary?
• Purity: Are functions predictable and free of hidden mutations?
• Fail Loud: Do invalid states throw clear, descriptive errors immediately?
• Readability: Does the logic read like an English sentence?