Custom platform migration
Migrate a custom ecommerce platform to Shopify Plus
Replace a bespoke, legacy or agency-built platform with Shopify Plus. We document the business logic hidden in your code, clean your data and rebuild your integrations, so nothing important is lost.
Why brands move
Why brands replace custom ecommerce platforms with Shopify
Maintenance costs
Hosting, security and bug fixes eat the budget meant for new features.
Key-person risk
One developer or agency holds all the knowledge.
Technical debt
Every change risks breaking something nobody remembers building.
Building what exists
Paying to build features Shopify gives you out of the box.
Build vs buy comparison
Custom platform vs Shopify Plus
| Custom platform | Shopify Plus | |
|---|---|---|
| Who maintains it | [Your team or agency] | [Shopify] |
| New features | [Built and paid for by you] | [Released by Shopify, plus apps] |
| Flexibility | [Total, at a cost] | [Functions, custom apps, or headless with Hydrogen] |
| Security & PCI | [Your responsibility] | [Included] |
| Hiring & handover | [Hard: bespoke knowledge] | [Easy: large talent pool] |
| Typical 3-year TCO | [£ range] | [£ range] |
Data & logic mapping
How your custom platform maps to Shopify
With bespoke platforms the hard part isn't the data. It's the business rules buried in the code.
| In your platform | Moves to in Shopify | Notes |
|---|---|---|
| Custom product data model | Products, variants, metafields & metaobjects | [Remodelled in discovery] |
| Bespoke pricing & discount rules | Shopify Functions | |
| Custom checkout logic | Checkout extensions & Functions | |
| In-house CMS | Theme sections, pages & metaobjects | |
| Direct database links to ERP / WMS | API integrations or middleware | See Shopify integrations |
| Admin tools & back-office screens | Shopify admin, Flow or custom apps | |
| Customers & order history | Customers & historical orders | [Data cleaned first; passwords reset] |
| URL structure | 301 URL redirects | Every indexed URL mapped |
Risks & how we handle them
Custom platform migration challenges, solved
-
Undocumented logic
We map every rule (pricing, stock, fulfilment) with your team before anything is built.
-
Messy data
Years of inconsistent data cleaned and standardised during migration.
-
Tightly coupled systems
Direct database links replaced with reliable, monitored API integrations.
-
Features you'll miss
A gap analysis up front, so there are no surprises at launch.
Headless option
Need a fully custom front end? Keep the flexibility with Shopify Hydrogen on Shopify's back end.
Process & timeline
Custom platform migration timeline
Timelines vary most here, so discovery comes first and is fixed-price.
Discovery & logic mapping
Rules, data, integrations and gap analysis.
Architecture & design
Data model, integrations plan and UX.
Build
Theme, Functions, custom apps, integrations.
Data cleansing & migration
Cleaned, imported and reconciled.
Launch & decommission
Go-live, then the old platform safely switched off.
Cost of ownership
What is your custom platform really costing you?
Send us your costs and we'll return a 3-year TCO comparison against Shopify Plus.
- Hosting & infrastructure
- £[X] / yr
- Development team or agency
- £[X] / yr
- Security, PCI & compliance
- £[X] / yr
- Features you're building that Shopify includes
- £[X] / yr
- Typical saving on Shopify Plus
- [X]%
Resources & insights
Replatforming resources
Download (gated)
Build vs buy: replatforming business case template
Get the templateInsight
[Is it time to retire your custom ecommerce platform?]
ReadInsight
[Headless vs Online Store 2.0: which is right for you?]
Read
FAQ
Custom platform migration FAQs
Can Shopify do everything our custom platform does?
Usually most of it, often with less code. We run a gap analysis in discovery: features become native Shopify, an app, a Shopify Function or a custom app. Anything that can't be matched is flagged before you commit, so there are no surprises at launch.
How long does it take to migrate from a custom platform?
Timelines vary more than with other platforms, because so much depends on undocumented logic and data quality. That's why we start with a fixed-price discovery, then give you a fixed-scope plan and timeline for the build.
What if our original developers are no longer around?
That's common. We work it out from the code, the database and the people who use the system every day, and document every rule before anything is rebuilt.
Should we go headless or use a Shopify theme?
Most brands are best served by an Online Store 2.0 theme: faster to build, easier for your team to edit and cheaper to run. Headless with Hydrogen makes sense when you need a truly custom front end. We'll recommend one in discovery.
Can you migrate from Visualsoft, Shopware or PrestaShop?
Yes. We migrate from hosted and open-source platforms as well as fully bespoke builds, using the same discovery, data mapping and SEO process.
Migration enquiry
Plan your move from a custom platform
Start with a fixed-price discovery that maps your logic, data and integrations.