Making David Protein's Cart 90% Faster

David Protein had everything dialled. Gorgeous site. Fantastic product. Ads and CRO all working.

But add-to-cart was noticeably, annoyingly slow. On every device. For every customer trying to buy.

And they couldn’t fix it.

The problem

The store converted. Traffic was strong. The product was in demand. The leak was the moment someone decided to buy.

Add-to-cart lagged on every device. Shoppers who were ready to purchase hit a pause — then another — before the cart even responded. That delay sat right on the highest-intent action on the site.

Nothing else was obviously broken. That’s why it was hard to see, and why previous attempts hadn’t landed.

What we changed

We didn’t redesign the site. We didn’t strip apps, kill video, or touch the brand.

We rebuilt how add-to-cart loads:

• Compressed and prioritised the assets that block the cart action
• Removed work that was competing with the click
• Made the interaction respond before the rest of the page finished catching up

Same theme. Same apps. Same visuals. The only change was how fast the buy button actually worked.

The result

We made add-to-cart 90% faster. Within one week:

• Cart add-to-cart rate was up 75.42%
• Average order value was up 10%
• That’s roughly an extra $960k per year

Zero new ad spend. Nothing else changed.

Identical site. Just much faster at the moment it mattered.

This is the pattern we see over and over: the revenue is already on the site. Speed is what stops it leaking at the weakest link.