Performance Optimization Summary

Problem Diagnosed

Your GitHub Pages site was loading slowly because:

  1. 20+ CSS files loading synchronously (render-blocking)
  2. 15+ JavaScript files loading without defer/async (render-blocking)
  3. Flash of Unstyled Content (FOUC) - slideshows appearing unstyled initially
  4. No critical CSS - essential styles not inlined

Solutions Implemented

1. Critical CSS Inlining

  • Created assets/css/critical.css with essential above-the-fold styles
  • Includes complete Swiper/slideshow styles to prevent FOUC
  • Inlined directly in <style> tags for instant rendering

2. Progressive CSS Loading

  • High Priority: Core styles (variables, base, typography) load immediately
  • Medium Priority: Component styles load after 100ms
  • Low Priority: Enhancement styles load after page load
  • External CSS (Bulma, Normalize) load asynchronously

3. Optimized JavaScript Loading

  • Critical scripts load immediately (theme, performance monitoring)
  • Essential libraries (GSAP, Swiper) load conditionally based on page content
  • Feature scripts load progressively (Swup, animations, etc.)
  • Non-essential scripts load after page load (cursor effects, search, etc.)

4. Conditional Loading

  • Gallery scripts only load if gallery elements detected
  • Video scripts only load if video elements detected
  • Icon libraries only load when needed

Files Modified

Core Files

  • _includes/styles-optimized.html - Performance-optimized CSS loading
  • _includes/scripts-optimized.html - Progressive JavaScript loading
  • assets/css/critical.css - Critical above-the-fold styles
  • _includes/head.html - Conditional optimization for production
  • _layouts/default.html - Uses optimized includes in production

Key Features

  • Production Detection: Optimizations only apply when JEKYLL_ENV=production
  • Fallback Support: <noscript> tags ensure styles load without JavaScript
  • Error Handling: Failed script loads are logged but don't break functionality
  • Performance Monitoring: Timing marks to measure load performance

Expected Results

Before Optimization

  • 20+ render-blocking CSS requests
  • 15+ render-blocking JavaScript requests
  • Visible FOUC on slideshows
  • Slow first contentful paint

After Optimization

  • 1 inline critical CSS block (instant)
  • Progressive asset loading (non-blocking)
  • No FOUC - slideshows styled immediately
  • Faster first contentful paint and interaction

Testing

Development Mode

bundle exec jekyll serve
# Uses standard includes for easier debugging

Production Mode

JEKYLL_ENV=production bundle exec jekyll serve
# Uses optimized includes for performance

GitHub Pages Deployment

  • GitHub Pages automatically sets JEKYLL_ENV=production
  • Optimizations will be active on your live site
  • No additional configuration needed

Performance Benefits

  1. Eliminated FOUC: Critical CSS ensures slideshows render styled immediately
  2. Reduced Render Blocking: CSS and JS load progressively instead of blocking
  3. Faster First Paint: Critical styles inline, everything else loads asynchronously
  4. Better User Experience: Content appears faster, interactions feel snappier
  5. Bandwidth Efficiency: Only loads scripts for features actually used on each page

Next Steps

  1. Deploy to GitHub Pages to see live performance improvements
  2. Use browser dev tools to verify no render-blocking resources
  3. Test on slow connections to confirm FOUC elimination
  4. Monitor Core Web Vitals for improved scores

The optimizations maintain full functionality while dramatically improving loading performance, especially on GitHub Pages where every millisecond counts for user experience.