Frontend Patterns

Frontend Patterns

1. Component Architecture

• Atomic Design: Organize components into Atoms, Molecules, Organisms, Templates, and Pages.
• Compound Components: Use context to share implicit state between parent and child components (e.g., <Select>, <Select.Option>).
• Render Props: Share code between React components using a prop whose value is a function.
• Custom Hooks: Extract stateful logic from a component so it can be tested independently and reused.

2. State Management

• Local State: Use useState or useReducer for state that is isolated to a single component or small subtree.
• Global State: Use context API, Redux, Zustand, or Jotai for application-wide state.
• Server State: Use React Query, SWR, or Apollo Client to manage asynchronous data fetching, caching, synchronization, and error handling.
• Form State: Use libraries like React Hook Form or Formik for complex forms.

3. CSS Patterns

• Utility-first CSS: Tailwind CSS conventions for rapid styling and consistency.
• CSS Modules: Scope CSS locally by default to avoid class name collisions.
• Styled-components: Write actual CSS in JavaScript, leveraging tagged template literals.

4. Performance Optimization

• Code Splitting: Use React.lazy and Suspense to lazy load components.
• Memoization: Use React.memo, useMemo, and useCallback to prevent unnecessary re-renders.
• Virtual Scrolling: Render only the visible items in a long list to save memory and processing time.

5. Accessibility (A11y)

• WCAG 2.1 Checklist: Follow guidelines for contrast, text resizing, and keyboard navigability.
• ARIA Patterns: Use ARIA attributes appropriately to enhance semantics for screen readers.
• Focus Management: Ensure logical tab order and visible focus states.

6. Testing

• Component Testing: Use React Testing Library to test components from the user's perspective.
• Visual Regression: Compare screenshots of components to detect unintended visual changes (e.g., Chromatic, Percy).
• E2E Testing: Automate browser actions to test critical user flows (e.g., Playwright, Cypress).

7. Design System Integration

• Token Consumption: Map design tokens (colors, typography, spacing) to CSS variables or a theme provider.
• Component Composition: Build complex UIs by composing simpler, reusable design system components.

8. SEO

• Meta Tags: Use next/head or react-helmet for dynamic meta tags.
• Structured Data: Inject JSON-LD to help search engines understand page content.
• SSR/SSG: Leverage Next.js or Remix for server-side rendering or static site generation.