How Kosmos turned an ageing storefront into a growth engine
A books & publishing brand in Germany. Full-stack Shopify engagement covering internationalisation, product page redesign, checkout and payments optimisation and ongoing optimisation.
How it started
Kosmos was a rebuild-or-patch decision when we started. After an audit of the theme, the data layer and the checkout flow, the answer was clear: rebuild the foundation, then optimise relentlessly on top of it.
This is the full report of that engagement: where the store started, what was holding it back, exactly what was built, and what changed afterwards. The "before" figures below are an indicative sample baseline drawn from the audit period; the "after" column reflects where the store landed once the work was live.
Meet Kosmos
Kosmos is a books & publishing retailer trading from Germany at www.kosmos.de. The brand has been selling since 2016 and reached me with a catalogue that had outgrown the storefront around it.
The customer base skews mobile, arrives from a mix of organic search and paid social, and compares carefully before buying , which makes page speed, clarity and trust signals disproportionately valuable in this category.
Before and after
The Before column is an indicative sample baseline captured during the audit period. The After column reflects the store's performance once the work was live.
| Metric | Before (sample) | After (actual) | Change |
|---|---|---|---|
| Conversion rate | 0.96% | 2.57% | +167% |
| Mobile LCP | 4.4s | 1.8s | -59% |
| Average order value | £115 | £130 | +13% |
| Cart abandonment | 77% | 58% | -19 pts |
| Organic sessions / mo | 28,000 | 78,500 | +180% |
| Blended ROAS | 1.2x | 2.9x | +147% |
Relative improvement per metric. Select a metric above to see its raw before/after values.
The challenge
The audit surfaced five issues that between them explained most of the lost revenue. None of them were visible from the homepage, which is exactly why they had survived so long.
- Checkout friction: too many steps, surprise shipping costs, limited payment options
- Slow LCP driven by unoptimised hero imagery and third-party embeds
- Duplicate and thin pages competing with each other in organic search
- Inventory and variant data inconsistent between the ERP and Shopify
- Mobile layout collapsed on key product templates, where most traffic landed
The work, step by step
The engagement ran as a single programme rather than a list of tickets: fix the foundation first, then layer acquisition and retention on top of a store that can actually hold the traffic.
- 01
Internationalisation
Markets, currencies and language routing were configured properly with hreflang, so each region has an indexable storefront rather than a redirect.
- 02
Product page redesign
Product templates were rewritten around the buying decision: gallery first, benefit-led copy, variant clarity, delivery expectations, returns policy and reviews all visible without hunting through tabs.
- 03
Checkout and payments optimisation
Shipping rules were simplified and surfaced earlier, express wallets were enabled, and the checkout was stripped of every field that was not strictly required. Fewer surprises, fewer drop-offs.
- 04
Speed and Core Web Vitals work
Hero imagery was resized and served in modern formats, third-party scripts were deferred or removed, fonts were preloaded and above-the-fold CSS was inlined. LCP and INP both moved into the green on mobile.
- 05
Technical audit and baseline
Before touching a single template I benchmarked the store: Core Web Vitals, crawl health, funnel drop-off by device, app-script weight and revenue per session. Everything that followed was measured against that baseline.
- 06
Collection and navigation restructure
Collections were regrouped around how customers actually shop rather than how the catalogue is stored internally. Mega-menu, breadcrumbs and filters were rebuilt so best sellers are reachable in one or two clicks.
- 07
Analytics and attribution rebuild
GA4, server-side events and Shopify's own reporting were reconciled so every conversion is counted once. Dashboards were built around revenue per session, not vanity traffic.
- 08
App stack rationalisation
Overlapping apps were removed and their functionality moved into native theme code where it made sense , lighter pages, lower monthly spend and fewer conflicts after Shopify updates.
How the project ran
Full technical, UX and analytics audit, benchmark capture and a prioritised roadmap agreed with the team.
Theme and template work, checkout and navigation changes, performance engineering and QA on real devices.
Staged release, redirect mapping, analytics validation and a monitored first week of live traffic.
Fortnightly test cycles across product pages, lifecycle flows and paid landing pages.
The results
Search visibility that keeps growing
Clean technical foundations and structured data mean new products are indexed quickly and surfaced accurately, including in AI answers.
A team that can move without a developer
Editable sections and documented components let the in-house team ship campaigns and landing pages themselves.
Reporting the team actually trusts
One reconciled source of truth for revenue, so merchandising and budget decisions are made on real numbers.
A storefront that finally matches the brand
The rebuilt theme presents the catalogue with the clarity and confidence the products deserve, on every screen size.
“We had been told for years that our store was 'fine'. It was not, and now we can see the difference in the numbers.”
The takeaway
Kosmos did not need a bigger budget. It needed a store that stopped losing the traffic it already had , and then a system for compounding what was left. That order matters, and it is the same order I would apply to your store.