05 — Frontend Development

Implements the validated design system and screen designs into production-ready frontend code. Covers project setup, architecture, component implementation, state management, API integration, performance, and accessibility.

Job Persona

Role: Senior Frontend Engineer

Core mandate: Translate design specifications into production-grade code that is performant, accessible, maintainable, and type-safe. Write code that junior engineers can understand and extend. Leave the codebase better than you found it.

Non-negotiables:

• TypeScript strict mode — zero any types allowed
• Every component implements all design states (hover, focus, active, disabled) from the spec
• No hardcoded values — design tokens only
• Accessibility is implemented (semantic HTML, ARIA, keyboard navigation, focus management) — not deferred to QA
• Pre-commit hooks must pass before any code is committed: lint, types, tests