E-Commerce Platform: 3x Faster Page Loads, 40% Higher Conversions

The Challenge

A retail brand selling home goods online came to us with a familiar problem: their store looked fine but was losing customers they couldn't see leaving. Analytics showed a 68% bounce rate on product pages, and checkout abandonment was high.

A technical audit revealed the root cause immediately. Their storefront — built on a legacy stack — was serving unoptimised images, loading 3.2MB of JavaScript on the first visit, and scoring 28/100 on Google PageSpeed. On mobile, the largest contentful paint (LCP) was over 8 seconds.

Every second of load time was costing them conversions.

What We Did

Phase 1 — Technical Audit (Week 1) We profiled the existing site with Lighthouse, WebPageTest, and Chrome DevTools. We identified 11 critical performance issues: unoptimised images, render-blocking scripts, no caching strategy, no CDN, and a component architecture that hydrated the entire page on load. Phase 2 — Next.js Migration (Weeks 2–5) We rebuilt the product listing and product detail pages in Next.js using:

• Static Generation (SSG) for the product catalogue — pages pre-rendered at build time, served from the edge
• Incremental Static Regeneration (ISR) for inventory-sensitive pages so stock status stays current without a full rebuild
• next/image for automatic format conversion (WebP/AVIF), responsive sizing, and lazy loading
• Route-level code splitting to ensure no page loads JavaScript it doesn't need

Phase 3 — Core Web Vitals Tuning (Weeks 6–7) With the migration done, we focused on the three Google Core Web Vitals:

• LCP brought from 8.4s → 1.2s by preloading the hero image and moving it to a static asset CDN
• CLS eliminated by setting explicit width/height on all images and ads
• FID/INP improved by deferring non-critical third-party scripts (chat widget, analytics)

Phase 4 — SEO & Structured Data (Week 8) Product schema markup, breadcrumb schema, updated sitemap, and canonical URL fixes. This resulted in richer Google search previews and a measurable uptick in click-through rates within 3 weeks.

The Results

One month after go-live:

• Page load time (3G mobile): 8.4s → 2.8s (67% faster)
• Google PageSpeed score: 28 → 92
• Bounce rate on product pages: 68% → 40% (-28 points)
• Conversion rate: baseline +40% lift
• Organic search traffic: +22% (Core Web Vitals improvement as ranking signal)

The client's words: "We'd been losing sales we couldn't explain. Now we can see exactly why — and it's fixed."

Lessons

Performance is a feature, not an afterthought. A 1-second improvement in load time can increase conversions by 7%. At scale, that's real money. ISR is underused. Most teams default to either fully static or fully dynamic. ISR gives you the performance of static with the freshness of SSR — it's the right answer for most e-commerce use cases. Measure everything before you start. The audit phase is not optional. Without a baseline, you can't prove the value of what you built.