A four-part performance layer that speeds up the OpenCart 4 storefront without touching a single core file. Native lazy-loading adds loading="lazy" and decoding="async" to product and category images below the fold, with a configurable skip count so your hero and first-row images still load eagerly. The asset optimizer concatenates and minifies the theme's CSS and JS into hash-named, cache-busted bundles stored in OpenCart's storage cache directory, served with immutable far-future cache headers and ETag/304 support; already-minified .min files are bundled verbatim and never re-minified. Lightweight infinite scroll for category pages uses an IntersectionObserver to append the next page's product grid while leaving the real pagination links in the DOM for SEO and no-JS visitors. Finally, a Core Web Vitals tab explains LCP, CLS, and INP against the official thresholds, gives you a tuning checklist wired to your live settings, and ships a copy-paste measurement snippet for the browser console. Every rewrite fails open: on any error the original output passes through completely untouched.