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Work / Lumen Retail

A storefront rebuild that paid for itself in eleven weeks

A headless Next.js commerce build with a real performance budget, where the largest conversion gain came from deleting things rather than adding them.
Client
Lumen Retail
Sector
Commerce
Year
2025
Services
Web & Product
All case studies

3.4x

mobile conversion rate

0.8s

Largest Contentful Paint, from 4.6s

11wk

to full payback on build cost

The problem

Challenge

The existing storefront scored 19 on mobile performance and carried 2.1MB of JavaScript before a product image loaded. Mobile was 74% of sessions and 31% of revenue. The brief asked for a redesign; the audit said the design was not the problem.

What we did

Approach

In order, including the steps that changed the plan.

  1. 01

    Audit before redesign

    Session recordings and funnel instrumentation located the drop-off precisely: users left during the four seconds before the page became interactive. We proposed a rebuild on the existing visual language and measured that first.

  2. 02

    Server-render the commerce path

    Catalogue, product and cart pages render on the server with streaming, so the first meaningful paint no longer waits on a client-side data fetch. Client JavaScript on a product page fell to 94KB.

  3. 03

    Budget enforced in CI

    A pull request that pushes Largest Contentful Paint above one second or the bundle above its budget fails before review. The performance win has held for fourteen months, which is the part that usually does not.

  4. 04

    Then improve the design

    With the baseline fixed, we ran nine experiments on the checkout flow. Removing the account-creation step before payment was worth more than the previous three redesigns combined.

Where it landed

Outcome

Mobile conversion more than tripled against a stable traffic mix. The build cost was recovered in eleven weeks, and the performance budget in CI means the next team cannot quietly give it back.

Built with

  • Next.js
  • TypeScript
  • Stripe
  • Sanity
  • Vercel
“They talked us out of the redesign we asked for and into the rebuild we needed. The invoice was the same either way, which is how I knew the advice was honest.”
Marcus FeldChief Digital Officer, Lumen Retail
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