−94% page weight. Zero visible change.

For a beauty brand in the luxury segment, the design is the product. The store was built to match, with no visual compromise: an autoplay hero video, product videos on every page, catalog-quality images. The cost was measurable: the product page weighed 110 MB, LCP sat at 13.8 seconds, and on anything but fast wi-fi the mobile experience was effectively unusable.

The standard agency answer is a “redesign and relaunch” where speed is bought by cutting into the look. That was off the table here — and it is exactly the kind of constraint our method is built for: speed as pure engineering, with the design left untouched.

The work shipped as 38 gate-passed builds. Each build had to pass a screenshot-parity check — pixel comparison before/after across page types — before it could move on. One visible deviation and the build was rejected. The rollback path was a deliverable on par with the code.

Within those limits, everything the user can’t see was rebuilt:

• Video: 249 videos re-encoded to adaptive streaming; concurrent video decoders cut from 26 to 7; the mobile video payload from 23 MB to 1.25 MB.
• Images: 411 catalog images replaced in a scripted, logged operation — 826 MB → 311 MB (−62%), zero errors, full rollback log.
• Code: the CSS bundle from 907 KB to 435 KB, and third-party scripts deferred with self-disarming fallbacks.
• LCP discovery: the LCP element made discoverable to the browser on every product page — 31/31 now pass Google’s LCP-discovery audit (was 8/31).