Web performance

Web performance work is most useful when it connects browser behavior to real user experience. This path moves from measurement and budgets to concrete loading and rendering techniques.

Measure what users experience

• Core Web Vitals — a current overview of the user-centered metrics.
• Optimize Core Web Vitals with Lighthouse — turning diagnostics into action.
• Modern UX metrics on WebPageTest — evaluating loading and responsiveness in realistic conditions.
• Performance Budgets — making speed a constraint before regressions ship.

Improve loading

• Native image lazy-loading for the web — when and how to defer offscreen images.
• Better image lazy-loading in Chrome — browser behavior and practical tuning.
• Preload late-discovered hero images — improving priority for likely LCP resources.
• Adaptive Loading — adapting delivery to user and device constraints.

Design stable, responsive experiences

• Infinite scroll without layout shifts
• The PRPL pattern
• Fetch Priority

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