global

Global Standards

Priority: P0 — Universal Rules

Core Design

• Apply SOLID, especially Single Responsibility: each function, component, class, or service has one clear reason to change.
• Apply KISS: choose the simplest design that solves the current problem correctly.
• Apply DRY: remove repeated logic when the duplication is real and stable, not accidental similarity.
• Apply YAGNI: do not add abstraction, configurability, or extension points without a present need.

Readability

• Use intention-revealing names. A reader should understand purpose without decoding abbreviations.
• Guard clauses and early returns over deep nesting.
• Explicit data flow over hidden side effects.
• Keep units focused enough to reason about quickly. Split when one unit mixes unrelated responsibilities.
• Comments explain why, constraints, or non-obvious tradeoffs — not what the code already says.

Safety

• Validate and sanitize all untrusted input at every boundary.
• Handle errors explicitly. Never swallow exceptions or return failures that hide the cause.
• Add context when propagating errors so failures are diagnosable.
• Never hardcode secrets, tokens, or credentials.
• Never leak sensitive data, PII, or internal stack details to users, clients, or logs.
• Clean up owned resources: subscriptions, listeners, timers, streams, connections.

Security Baseline

Three rules that apply on every code write, regardless of context:

• No raw SQL string concatenation. Parameterized queries or ORMs only.
• No wildcard CORS on authenticated routes. Explicit allowlisted origins only.
• No full ORM entity returned from an API endpoint. Project to DTO always.
• No auth tokens in localStorage/sessionStorage. Use httpOnly cookies; deeper auth rules live in refs/auth.md.

Change Quality

• Remove dead code, debug code, and stale fallbacks before finishing.
• Cover changed logic and important edge cases with appropriate verification.
• Keep behavior, naming, and structure consistent with the existing project unless there is a clear reason to improve.