Magento Performance Optimisation

The challenge

An established Magento storefront had accumulated generic Magento and third-party frontend assets across catalogue pages. CSS from Magento core, the theme and installed extensions could enter the initial rendering path even when much of it was not needed by the page being viewed.

The aim was to make key product and category journeys more deliberate about the assets they load, without losing required Magento, extension or responsive behaviour.

The solution

Dedicated category and product LESS entry points replaced Magento’s generic styles-m.css and styles-l.css bundles on the targeted catalogue pages. Page-specific dependencies were retained while third-party assets were removed where they were not required.

Critical category CSS was prioritised and non-critical CSS deferred, with a noscript fallback and support for Magento’s versioned static asset URLs. Product pages received their own optimisation rather than being treated as an extension of the category approach.

Responsive product-image preloading and srcset improved early discovery of the likely largest contentful paint image. WebP and AVIF assets were preferred where available, while appropriate fallbacks preserved compatibility.

The outcome

The resulting architecture sends more relevant frontend assets to key catalogue pages, reduces unnecessary render-blocking dependencies and gives above-the-fold content greater priority while retaining a maintainable Magento frontend structure.

Technical highlights