The brief
The Mercer Brand needed an Online Store 2.0 rebuild that could carry a custom post-purchase upsell step through Checkout Extensibility, without the launch breaking the pixels the ads team depended on.
What we built
Theme rebuild on Online Store 2.0, section-based and merchant-editable
A Checkout Extensibility upsell step added post-purchase, not pre-checkout
Conversion tracking rebuilt alongside the theme, not bolted on after launch
Speed pass so Core Web Vitals held up once the new sections shipped