===================================================================== PERFORMANCE OPTIMIZATION GUIDELINES ===================================================================== Golf Cartify - https://golfcartify.com Phone: 1-844-552-0202 Last Updated: 2026-02-10 ===================================================================== This document outlines the performance optimization standards and best practices for the Golf Cartify website. These guidelines ensure fast page loads, smooth interactivity, and excellent user experience across all devices and network conditions. ===================================================================== 1. CORE WEB VITALS TARGETS ===================================================================== 1.1 LARGEST CONTENTFUL PAINT (LCP) --------------------------------------------------------------------- - Target: Less than 2.5 seconds - Measurement: Time for the largest visible content element to render - Key elements: Hero images, product grid images, main headings - Optimization strategies: - Preload LCP candidate images with fetchpriority="high" - Use optimized WebP format for hero and product images - Inline critical CSS for above-the-fold content - Minimize server response time (TTFB under 600ms) - Avoid lazy loading images in the first viewport - Use CDN for static asset delivery - Preconnect to required origins 1.2 FIRST INPUT DELAY (FID) --------------------------------------------------------------------- - Target: Less than 100 milliseconds - Measurement: Time from first user interaction to browser response - Optimization strategies: - Minimize main thread blocking time - Break up long JavaScript tasks into smaller chunks - Use web workers for heavy computations - Defer non-critical third-party scripts - Optimize event handlers for responsiveness - Reduce JavaScript bundle size through code splitting 1.3 CUMULATIVE LAYOUT SHIFT (CLS) --------------------------------------------------------------------- - Target: Less than 0.1 - Measurement: Visual stability during page load - Optimization strategies: - Set explicit width and height on all images - Reserve space for dynamically loaded content - Use aspect-ratio CSS property for responsive images - Avoid inserting content above existing content - Use transform animations instead of layout-triggering properties - Preload web fonts to prevent FOUT/FOIT - Set dimensions on ad slots and embeds 1.4 INTERACTION TO NEXT PAINT (INP) --------------------------------------------------------------------- - Target: Less than 200 milliseconds - Measurement: Responsiveness of all user interactions - Optimization strategies: - Optimize React component re-renders with memoization - Use React.memo, useMemo, and useCallback appropriately - Implement virtualized lists for large inventory displays - Debounce search and filter input handlers - Use requestAnimationFrame for visual updates - Keep event handlers lightweight and non-blocking ===================================================================== 2. MOBILE-FIRST INDEXING COMPLIANCE ===================================================================== 2.1 RESPONSIVE DESIGN REQUIREMENTS --------------------------------------------------------------------- - All pages must be fully responsive from 320px to 2560px - Use CSS Grid and Flexbox for responsive layouts - Implement responsive images with srcset and sizes attributes - Touch targets must be minimum 48x48 CSS pixels - Font sizes must be legible without zooming (minimum 16px base) - Horizontal scrolling must not occur at any viewport width - Content parity between mobile and desktop versions 2.2 MOBILE PERFORMANCE TARGETS --------------------------------------------------------------------- - Target 3G connection speeds for baseline performance - Total page weight under 1.5 MB for initial load - JavaScript bundle under 300 KB gzipped for initial load - Critical CSS inlined (under 14 KB) - Time to Interactive under 5 seconds on mid-range devices - Smooth scrolling at 60fps on mobile devices 2.3 VIEWPORT AND META CONFIGURATION --------------------------------------------------------------------- - Proper viewport meta tag: width=device-width, initial-scale=1 - Theme color meta tag matching brand colors - Apple mobile web app capable meta tags - Prevent auto-zoom on iOS input focus (font-size: 16px minimum) ===================================================================== 3. CACHING STRATEGY ===================================================================== 3.1 API CACHE REFRESH SCHEDULE --------------------------------------------------------------------- - Inventory API cache refresh: Daily at 10:45 PM EST - Brand data cache: Refreshed weekly or on update - Location data cache: Refreshed monthly or on update - Pricing data: Synced with inventory refresh cycle - Cache invalidation: Automatic on DMS data push - Stale-while-revalidate: 1 hour for inventory data - Cache TTL for static content: 30 days minimum 3.2 BROWSER CACHING HEADERS --------------------------------------------------------------------- - HTML pages: no-cache, must-revalidate - CSS/JS bundles (hashed): max-age=31536000, immutable - Images (product): max-age=86400, stale-while-revalidate=3600 - Fonts: max-age=31536000, immutable - API responses: max-age=300, stale-while-revalidate=600 - Service worker: no-cache, no-store - Manifest and favicon: max-age=604800 3.3 CDN CONFIGURATION --------------------------------------------------------------------- - Static assets served via CDN edge locations - Image assets from S3: s3.amazonaws.com/prod.docs.s3/carts/ - CDN cache purge on deployment - Geo-distributed edge caching for 11 location areas - Brotli compression enabled at CDN level - HTTP/2 and HTTP/3 support enabled ===================================================================== 4. ASSET OPTIMIZATION ===================================================================== 4.1 IMAGE LAZY LOADING --------------------------------------------------------------------- - Native lazy loading (loading="lazy") for below-fold images - Above-fold images load eagerly with fetchpriority="high" - Intersection Observer fallback for older browsers - Low-quality image placeholders (LQIP) during loading - Progressive JPEG/WebP for perceived performance - Skeleton loaders for product grid during data fetch 4.2 CODE SPLITTING --------------------------------------------------------------------- - Route-based code splitting via React.lazy and Suspense - Dynamic imports for heavy components: - Inventory filters and search functionality - Cart detail image galleries - Financing calculator - Map/location components - Admin dashboard (if applicable) - Vendor chunk separation for stable caching - Common chunk extraction for shared dependencies 4.3 TREE SHAKING --------------------------------------------------------------------- - ES module imports only (no CommonJS in client code) - Import specific functions, not entire libraries - Configure Vite for optimal tree shaking - Audit bundle for unused dependencies regularly - Use bundle analyzer to identify dead code 4.4 MINIFICATION --------------------------------------------------------------------- - JavaScript: Terser minification via Vite build - CSS: PostCSS with cssnano for production builds - HTML: Minified during build process - SVG: SVGO optimization for all vector assets - JSON: Minified API responses in production - Remove console.log and debugger statements in production ===================================================================== 5. NETWORK OPTIMIZATION ===================================================================== 5.1 RESOURCE HINTS --------------------------------------------------------------------- Preconnect to critical third-party origins: - - - - - 5.2 PRELOADING CRITICAL ASSETS --------------------------------------------------------------------- - Preload hero image for LCP improvement - Preload primary web font (WOFF2 format) - Preload critical above-fold CSS - Prefetch next likely navigation routes - Preload logo and brand-critical images 5.3 COMPRESSION --------------------------------------------------------------------- - Brotli compression for all text-based assets (preferred) - Gzip fallback for older clients - Compression level: Brotli 4 for dynamic, 11 for static - Minimum compression threshold: 1 KB file size - Compressed content types: HTML, CSS, JS, JSON, SVG, XML 5.4 HTTP PROTOCOL OPTIMIZATION --------------------------------------------------------------------- - HTTP/2 enabled for multiplexed connections - HTTP/3 (QUIC) support where available - Server push disabled (browser support deprecated) - Connection keep-alive enabled - Maximum concurrent connections optimized per origin ===================================================================== 6. JAVASCRIPT OPTIMIZATION ===================================================================== 6.1 BUNDLE SIZE TARGETS --------------------------------------------------------------------- - Main bundle: Under 150 KB gzipped - Vendor bundle: Under 100 KB gzipped - Route chunks: Under 50 KB gzipped each - Total initial JavaScript: Under 300 KB gzipped - Total page JavaScript (all chunks): Under 500 KB gzipped 6.2 RUNTIME PERFORMANCE --------------------------------------------------------------------- - Avoid forced synchronous layouts - Batch DOM reads and writes - Use CSS containment for complex components - Implement virtual scrolling for inventory lists (50+ items) - Debounce window resize and scroll event handlers - Use passive event listeners where appropriate - Avoid memory leaks in React useEffect cleanup ===================================================================== 7. RENDERING OPTIMIZATION ===================================================================== 7.1 REACT WITH VITE --------------------------------------------------------------------- - React 18+ with concurrent features - Vite for fast development and optimized production builds - SSR-ready architecture for future server-side rendering - Automatic code splitting via dynamic imports - Hot Module Replacement (HMR) for development efficiency - Production build with Rollup optimization 7.2 PROGRESSIVE ENHANCEMENT --------------------------------------------------------------------- - Core content accessible without JavaScript - Semantic HTML structure for baseline functionality - CSS-first animations and transitions - JavaScript enhances, not enables, core experiences - Graceful degradation for unsupported features - No-JavaScript fallback for critical information display 7.3 REACT PERFORMANCE PATTERNS --------------------------------------------------------------------- - React.memo for expensive pure components - useMemo for expensive computations in render - useCallback for stable function references - Key prop optimization for list rendering - Avoid inline object/array creation in JSX props - State colocation to minimize unnecessary re-renders - Context splitting to prevent broad re-renders ===================================================================== 8. MONITORING & MEASUREMENT ===================================================================== 8.1 GOOGLE PAGESPEED INSIGHTS --------------------------------------------------------------------- - Target score: 90+ for both mobile and desktop - Run audits before and after deployments - Address all "Opportunities" and "Diagnostics" findings - Monitor scores weekly for regression detection - Document baseline scores for all key pages: - Homepage - Inventory listing page - Cart detail page - Financing page - Location pages 8.2 LIGHTHOUSE AUDITS --------------------------------------------------------------------- - Performance: Target 90+ - Accessibility: Target 95+ - Best Practices: Target 95+ - SEO: Target 95+ - Run Lighthouse CI in deployment pipeline - Track scores over time for trend analysis - Address all failing audits before deployment 8.3 WEB VITALS TRACKING --------------------------------------------------------------------- - Implement web-vitals library for Real User Monitoring (RUM) - Track CWV metrics: LCP, FID, CLS, INP, TTFB - Report metrics to analytics dashboard - Set up alerts for CWV regression - Segment data by device type, connection speed, and location - Monthly performance review and optimization sprint - 75th percentile targets for all CWV metrics 8.4 ERROR MONITORING --------------------------------------------------------------------- - Client-side error tracking implementation - Monitor JavaScript runtime errors - Track failed API requests and timeouts - Alert on error rate spikes - Log slow API responses (over 2 seconds) - Monitor 404 and other HTTP error rates ===================================================================== 9. DEPLOYMENT PERFORMANCE ===================================================================== 9.1 BUILD OPTIMIZATION --------------------------------------------------------------------- - Production builds with full optimization enabled - Source maps generated but not served to clients - Asset fingerprinting for cache busting - Pre-compressed assets (Brotli and Gzip) - Automated build size monitoring 9.2 PERFORMANCE BUDGET --------------------------------------------------------------------- - Total page weight: Under 2 MB (initial load) - Total requests: Under 50 (initial load) - Time to First Byte: Under 600ms - First Contentful Paint: Under 1.8s - Time to Interactive: Under 3.8s - Speed Index: Under 3.4s ===================================================================== END OF PERFORMANCE OPTIMIZATION GUIDELINES ===================================================================== Golf Cartify | https://golfcartify.com | 1-844-552-0202 =====================================================================