CASE STUDY · 2026
The Sweater Shop.
Milk Bottle Labs migrated The Sweater Shop from Magento to Shopify Plus — a complete platform migration including all orders, customer history and product data, completed without disruption for one of Ireland's most beloved retail brands.
THE CHALLENGE
Moving forty years of retail history to a modern platform — without losing a day's trade.
The Sweater Shop has been a fixture on Nassau Street since the 1980s. Generations of Dubliners and international visitors know the store well — it is Ireland's most recognised destination for Aran knitwear, Irish gifts and quality woollen goods shipped worldwide. When it came time to leave Magento behind, the stakes were high. Every order, every customer record, and years of transactional history had to move cleanly to Shopify Plus.
The project demanded precision. A botched migration for a brand this established could mean lost revenue, confused customers and trust damaged over decades. Milk Bottle Labs delivered the complete migration — products, orders, customer accounts and historical data — on time, without disruption, and with the client confident from kickoff to launch day.
WHAT WE DELIVERED
- 01
Overview
Founded in the 1980s and located at 30 Nassau Street in the heart of Dublin 2, The Sweater Shop is one of Ireland's most iconic retail destinations. Specialising in authentic Aran knitwear, Irish gifts and quality woollen goods, the store has served generations of customers — both local Dubliners and visitors from all over the world. When the business decided to move its online store to Shopify Plus, Milk Bottle Labs was brought in to manage the full migration from Magento, including the complete transfer of all historical orders and customer data.
- 02
The challenge
Magento is a capable platform, but over time it becomes a burden rather than an asset. Hosting costs rise, technical maintenance demands grow, and the ability to move quickly — to launch new collections, run seasonal promotions, update the store — is constantly held back by complexity. For The Sweater Shop, which balances a busy bricks-and-mortar presence at one of Dublin city centre's most visited addresses with a growing international online business, that friction had to go. The decision to migrate was clear. The execution required real care. Decades of customer accounts, thousands of orders and years of product history all had to move cleanly to the new platform. There was no appetite for data loss, downtime or confusion for the loyal customers who had been shopping with The Sweater Shop for years — in some cases for generations.
- 03
What we did
Milk Bottle Labs handled the migration from end to end. We began with a full audit of the Magento store — cataloguing the product range, reviewing order data, mapping customer accounts and identifying edge cases that would need particular attention during the transfer. The data migration covered the complete history of the store. All orders were migrated to Shopify Plus, preserving the transaction records the business relies on for reporting, customer service and returns. Customer accounts were moved cleanly, ensuring that returning shoppers found their history intact and their experience uninterrupted on the new platform. The Shopify Plus store was built to reflect the quality and character of The Sweater Shop brand — clean, navigable, and well-suited to both a domestic Irish audience and the international visitors who form a significant part of the store's online customer base. The theme was developed to showcase the product range clearly, with strong imagery, intuitive filtering and a checkout experience optimised for conversion. We managed the full project from discovery through to launch, including QA testing, redirect mapping for SEO continuity, and hands-on support during the go-live period to make sure the team felt fully confident on the new platform from day one.
- 04
The result
The migration completed on schedule and without disruption. The Sweater Shop's online store launched on Shopify Plus with its full order history, customer records and product catalogue intact. The transition from Magento was seamless — no meaningful downtime, no data loss, and no negative impact on customers. The client was delighted with how the project ran and with the store that went live. The new Shopify Plus store positions The Sweater Shop for the next chapter of its growth. The platform is faster to manage, easier to update, and built to scale alongside a brand that has been getting it right for over forty years.
- 05
Klaviyo email marketing
Alongside the Shopify Plus store build, Milk Bottle Labs integrated Klaviyo and built a complete email marketing programme for The Sweater Shop from the ground up. Klaviyo is the email marketing platform built specifically for Shopify and Shopify Plus merchants, and the native Shopify integration means customer data, order history, product catalogue and real-time behaviour sync automatically — no manual exports, no third-party connectors. We redesigned the email templates to match the new store aesthetic — clean, on-brand layouts built in the Klaviyo email editor that render correctly across all major email clients and devices. The automated Klaviyo flows built for The Sweater Shop include a welcome series for new email subscribers, an abandoned cart flow to recover lost revenue, a browse abandonment sequence for customers who viewed products without purchasing, and a post-purchase flow that nurtures the customer relationship after every order. Klaviyo segments were configured to separate the audience by purchase history, geography and engagement level — enabling targeted email campaigns rather than blanket newsletters. Every flow was tested before launch, including A/B tests on subject lines and send timing, so the Klaviyo email programme was generating revenue from day one. For a brand with a loyal, established customer base like The Sweater Shop, Klaviyo's email automation and segmentation capabilities represent one of the highest-return investments available on the Shopify Plus platform.
HOW IT SHIPPED
How it shipped. Then onward, together.
| Week 1–2 | Discovery & audit | Full review of the Magento store — products, orders, customer data, URL structure and third-party integrations. |
| Week 3–6 | Store build | Shopify Plus store build, custom theme development, product import, navigation and checkout configuration. |
| Week 7–9 | Data migration | Full migration of all orders, customer accounts, historical transaction data and SEO redirect mapping. |
| Week 10–12 | QA & launch | End-to-end testing, UAT with the client team, go-live, and dedicated post-launch support. |
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