Clean Code Standards

This skill provides the foundational principles enforced by the Church of Clean Code purist agents.

The Ten Pillars of Clean Code

1. Type Safety

• No any types - use unknown with guards
• No type assertions (as) - use runtime validation
• Exhaustive switch statements with never checks
• Branded types for domain safety

2. Git Hygiene

• Conventional Commits format required
• Atomic commits (one logical change per commit)
• No WIP commits on main branches
• Clean worktree at session end

3. Architecture Boundaries

• Domain layer depends on NOTHING
• Dependencies flow downward only
• No circular dependencies
• Repository interfaces in domain, implementations in infrastructure

4. Test Coverage

• Domain: 90% coverage minimum
• Application: 80% coverage minimum
• All entities require property tests (fast-check)
• No weak assertions (toBeTruthy without context)

5. Dead Code Elimination

• Zero unused exports
• Zero orphaned files
• No commented-out code (git remembers)
• TODOs older than 3 months must be actioned or deleted

6. Naming Clarity

• File format: [name].[component-type].ts
• Booleans: is/has/should/can/will/did prefixes
• No generic names: data, result, temp, info
• Collections plural, items singular

7. Size Limits

• Components: max 350 lines (critical at 500)
• Functions: max 40 lines (suspicious), 80 lines (condemned)
• Nesting: max 4 levels
• No god classes

8. Secret Security

• Zero secrets in code or git history
• Environment variables for all credentials
• .gitignore must cover all secret patterns
• Rotation required if ever committed

9. Dependency Health

• Zero known vulnerabilities
• No packages >2 major versions behind
• No unused dependencies
• devDependencies vs dependencies properly separated

10. Observability

• No empty catch blocks
• Structured logging with correlation IDs
• All endpoints traced
• Health checks for all dependencies

11. Accessibility (Universal Readability)

• All images have alt text (descriptive or null)
• Text contrast: 4.5:1 minimum (3:1 for large text)
• No information conveyed by color alone
• All interactive elements keyboard accessible
• Focus indicators visible (3:1 contrast)
• ARIA used correctly (or native HTML preferred)
• No keyboard traps

12. High-Converting Copy

• No "Submit" buttons without context - use specific action verbs
• No no-reply email addresses - use monitored addresses
• Hero headlines must state a clear benefit
• Features must connect to benefits (FAB framework)
• Landing pages must follow AIDA/PAS/4Ps structure
• SMS messages must be under 160 characters
• Error messages must include next steps

13. Adaptive UI

• No hardcoded 100vw/100vh -- use %, dvh, container queries
• Foldable hinge awareness via viewport segment APIs
• Canonical layouts (List-Detail, Feed, Supporting Pane) for wide screens
• State preservation across resize, fold, rotate (forms, scroll, navigation)
• Focus-visible styles on all interactive elements, no outline: none
• All images have srcset for multi-DPI support, icons are SVG
• Touch targets minimum 44x44 CSS pixels
• No hover-only interactions -- touch/keyboard alternatives required
• Drag-and-drop has visual feedback and keyboard alternative

When to Invoke Crusades