Book a Call

Custom and Headless Platform to Shopify Migration

A custom platform to Shopify Plus migration moves your products, customers, orders and content out of a custom built or headless store’s database into Shopify, rebuilds your custom business logic with Shopify Functions and apps, reconnects your ERP, PIM, OMS and WMS, and 301 redirects every old URL. Ecomzier plans, tests and launches the move.

Get a Free Migration Plan

Try before you buy: review a working copy of your store on Shopify before you commit.

Who is a custom platform to Shopify Plus migration for?

Unlike a move between two hosted platforms, a custom platform migration has no standard export and no standard data model. Every project starts by reading your database and your code. These are the custom stores we migrate most often:

Custom built PHP, .NET and Java stores

Your store runs on code your team or an agency wrote years ago, on your own servers or cloud. Every security patch, upgrade and peak season is your problem. We move the data and the logic that still earns its keep.

Legacy in house platforms

Older commerce systems often sit inside an ERP or a back office tool, with business rules nobody has documented. We map those rules first, so nothing that matters is lost in the move.

Headless and composable setups

A custom front end on a commerce engine or microservices gives you control, but also a large bill for hosting and engineering. We help you choose between a Shopify theme and headless Shopify.

Custom B2B and wholesale portals

Account pricing, quotes, credit terms and approval flows built from scratch. We map them to Shopify B2B on Plus, and rebuild the rest with Shopify Functions and custom apps.

Source	How we extract	Best for
SQL databases (MySQL, PostgreSQL, SQL Server, Oracle)	Read only SQL exports or a database replica, with queries written against your schema.	Most custom PHP, .NET and Java stores, where the database is the single source of truth.
Your platform’s own API	Paged API calls from a migration script, with rate limits respected.	Headless setups and platforms where business rules live in the API layer rather than the database.
ERP or PIM as the master	Exports or API pulls from the system that owns products, prices or stock.	Stores where the website was only a window on the ERP or PIM.
Flat files and feeds	CSV, XML or product feed files, checked against the database for gaps.	Small data sets, legacy archives and data that only exists in spreadsheets.
Media and files	Image and document folders copied from your servers or object storage.	Product images, downloads and blog media, uploaded to Shopify and relinked.

Custom platform data	Shopify object	How we map it
Products and SKUs	Products and variants	Each sellable SKU becomes a variant with its own SKU, price, stock, weight, barcode and image.
Product attributes	Options, metafields or both	Attributes that create SKUs become up to three options. Descriptive attributes become typed metafields that themes and filters can use.
More than three variant attributes	Restructured	Products are split into linked products, or attributes without their own stock move to metafields or line item properties.
Lookup tables (brands, materials, size charts, stores)	Metaobjects	Each table becomes a metaobject definition with entries, referenced from products through metafields.
Categories	Collections and menus	Categories become manual or automated collections, and the tree becomes your navigation menu.
Customers and addresses	Customers	Names, emails, phones, addresses, tags and marketing consent move. Extra customer fields become customer metafields.
Customer passwords	Not moved	Hashed passwords cannot be moved. With Shopify new customer accounts, customers sign in with a one time 6 digit code instead.
Historical orders	Orders, via API or app	Shopify admin CSV import covers products and customers, while historical orders need a migration app or the API (Shopify Help Center). We import products, then customers, then orders so every order links correctly.
Gift cards and store credit	Gift cards, via API	Open balances move through the API or a migration app (Shopify Help Center) and are reconciled against your ledger.
Content pages and blog posts	Pages and blog articles	Copy, images, authors and dates move, with internal links rewritten to the new URLs.
SEO titles and meta descriptions	SEO fields	They move into the SEO fields of each product, collection, page and article.

Moving to Shopify: Liquid theme or headless?

Leaving a custom or headless platform does not mean you have to stay headless. Shopify supports three front end models, and we recommend one based on what your team needs to change, how often, and who maintains it.

Hydrogen is Shopify’s headless framework, and Shopify describes Hydrogen projects as React Router apps preconfigured with Shopify specific features. Oxygen is Shopify’s hosting for Hydrogen storefronts, available at no extra charge on paid Shopify plans including Plus (Shopify developer docs).

Front end option	How it works	Best when
Liquid theme (Online Store)	Shopify hosts the storefront. Pages are built with Liquid sections and blocks that your team edits in the theme editor.	You want the lowest running cost, fast launches, and a marketing team that changes pages without developers.
Hydrogen on Oxygen	A React Router storefront built with Shopify’s Hydrogen framework and deployed to Shopify’s Oxygen hosting.	You need a fully custom experience, have React developers, and want Shopify to host the front end.
Your own headless front end	Any framework or app reads products and carts through the Storefront API and runs on your own hosting.	You already run a front end, mobile app or content platform you want to keep, and only replace the commerce engine.

Many stores that went headless for speed or flexibility find a modern Shopify theme covers what they need. We tell you honestly if headless still pays off for your store.

Rebuilding custom business logic on Shopify

Custom platforms carry years of rules hard coded into checkout, pricing and fulfillment. On Shopify, that logic moves into Shopify Functions, checkout UI extensions, Shopify Flow and custom apps. One plan detail matters: stores on any plan can use public App Store apps that contain functions, but only stores on Shopify Plus can use custom apps that contain Shopify Function APIs (Shopify developer docs). That is a key reason custom platform merchants move to Plus.

Custom logic on your platform	Shopify equivalent	Notes
Pricing and discount rules	Discount functions	Tiered, bundle, customer specific and stacked discounts written as functions in a custom app.
Bundles and line item price changes	Cart transform function	Merge, expand or reprice cart lines, such as kits and bundles built from components.
Shipping rules	Delivery customization functions	Hide, rename or reorder delivery options by product, address or customer.
Payment rules	Payment customization functions	Hide or reorder payment methods, for example net terms only for approved accounts.
Order validation	Cart and checkout validation functions	Minimum quantities, restricted products by region and purchase limits are enforced at checkout.
Fulfillment and warehouse routing	Fulfillment constraints and order routing functions	Rules that keep items together or route orders to specific locations.
Custom checkout fields and messages	Checkout UI extensions	Extensions for the information, shipping and payment steps are available only on Shopify Plus (Shopify developer docs).
Back office jobs and scheduled tasks	Shopify Flow or a custom app	Tagging, alerts and approval steps move to Flow. Heavier jobs run in a custom app on the Admin API and webhooks.

System	What usually syncs	How we connect it
ERP	Products, prices, stock, customers, orders, invoices and payment terms.	An existing Shopify connector where one fits, or middleware or a custom app with clear rules for which system owns each field.
PIM	Product content, attributes, media and translations.	Attributes mapped to options, metafields and metaobjects, published to Shopify through the API.
OMS	Orders, order status, splits, returns and refunds.	Orders sent by webhook, with fulfillment and status updates written back to Shopify.
WMS and 3PL	Stock levels by location, shipments and tracking.	Each warehouse becomes a Shopify location, with stock and tracking synced through the API.
CRM, marketing and accounting tools	Customers, consent, orders and payouts.	Native Shopify apps where available, or a custom integration when your tool has none.

How we keep your SEO when moving from a custom platform to Shopify

Custom platforms can use any URL scheme: script names, numeric IDs, file extensions, query strings. Shopify uses fixed URL prefixes (/products/, /collections/, /pages/, /blogs/), so nearly every URL changes. Rankings survive when each old URL points to the right new page. Our SEO checklist:

A full URL inventory. We crawl the site, pull URLs from your database and server logs, and add indexed and linked URLs from Search Console and backlink tools.
Pattern based mapping. We decode how your platform builds URLs, then generate redirects from the database so each old product, category and page URL maps to its new Shopify handle.
A one to one redirect map. Every URL gets a 301 redirect to its Shopify equivalent, imported by CSV. No mass redirects to the homepage, and no redirect chains.
Metadata and content kept. Page titles, meta descriptions, headings, image alt text and copy move unchanged.
Sitemap resubmitted. Shopify generates /sitemap.xml automatically (Shopify Help Center). We submit it in Google Search Console and Bing Webmaster Tools on launch day.
Post launch checks. We test old URLs on the live domain and watch Search Console for 404s, fixing any gaps.

Typical custom platform URL patterns and where they go:

Custom platform URL	Shopify URL	Notes
/product/10482/oak-cheese-grater	/products/oak-cheese-grater	ID based paths are matched to the product through the ID in your database.
/catalog/kitchen/graters.aspx	/collections/graters	File extensions such as .php, .aspx and .jsp are dropped. Each category becomes a collection.
/item.php?id=10482	/products/oak-cheese-grater	Query string URL. Mapped and tested one by one, because Shopify warns these might not redirect as expected.
/content/about-us.html	/pages/about-us	Content pages become Shopify pages.
/news/2024/05/post-title	/blogs/news/post-title	Blog posts become articles in a Shopify blog.

Shopify URL redirects are 301 redirects, can be imported by CSV, and only work from URLs that no longer load a page. Stores can hold up to 100,000 redirects, or 20,000,000 on Shopify Plus. Shopify notes that URLs with query strings might not work as expected (Shopify Help Center). We flag every query string URL that carries traffic or backlinks before launch and agree how each one is handled.

Step 01
Discovery and code audit
We read your database schema, code, integrations and URLs, and list every business rule your platform runs. You receive a written migration plan.
Step 02
Data and logic mapping
Tables are mapped to Shopify objects, and each custom rule to a Shopify feature, function, app or custom app. You approve the plan.
Step 03
Build and test migration
We build the storefront, Shopify Functions, apps and integrations, then run a full test import from staging while your current site stays live.
Step 04
Redirects and SEO setup
The redirect map, metadata, alt text and internal links are loaded and checked against the crawl, URL by URL.
Step 05
Launch and monitoring
A final delta migration moves new orders and customers, domains switch, the sitemap is submitted and Search Console is watched after launch.

Get your free custom platform to Shopify Plus migration plan

Tell us about your platform and our migration team will send a free, step by step plan covering your data, business logic, integrations, URLs and timeline.

Get My Free Plan

Your personal information will be processed in accordance with Shopify’s Privacy Policy

Project type	Typical scope	Typical timeline
Simple custom store	Clean database, under 5,000 products, little custom logic, one or two integrations	6 to 10 weeks
Mid market custom platform	Larger catalog, custom pricing or shipping rules, ERP and several integrations	10 to 16 weeks
Enterprise, B2B or headless	Complex logic, B2B portal, ERP, PIM, OMS and WMS, or a headless front end	16 to 28 weeks

Typical ranges for planning only, not a quote or a guarantee. Your audit sets the actual schedule.

Factor	Why it matters
Database quality and documentation	Clean, documented schemas map quickly. Undocumented tables, duplicates and data spread across systems take longer to decode and clean.
Custom business logic	Each pricing, shipping, payment or validation rule is rebuilt as a Shopify feature, a function or custom app code, and tested.
Integrations	ERP, PIM, OMS, WMS, CRM and accounting connections each need mapping, building and end to end testing.
Catalog structure	Products with more than three variant attributes, or many lookup tables, need restructuring into variants, metafields and metaobjects.
Order history	Years of orders take longer to import and reconcile than products and customers.
URL complexity	Query string and ID based URLs need more mapping and testing than clean, readable URLs.
Front end choice	Adapting a Shopify theme costs less than a custom theme, and a headless Hydrogen build costs more than both.

Area	Custom platform	Shopify Plus
Hosting	You run and scale servers or cloud infrastructure yourself.	Hosting is included and managed by Shopify, and Hydrogen storefronts can run on Oxygen.
Security and PCI	You are responsible for patches, monitoring and PCI compliance for your checkout.	Shopify is certified Level 1 PCI DSS compliant (Shopify security).
Upgrades	Framework, language and library upgrades are projects your team plans and pays for.	Shopify updates the core platform for you, so staying current is not a project on your roadmap.
Business logic	Any rule you can code, but every rule is yours to maintain.	Shopify Functions, checkout UI extensions, Flow and custom apps, with function custom apps on Plus.
Integrations	Point to point code against your own database.	The Admin API, webhooks and the Shopify App Store.
Total cost drivers	Hosting, developers, security, compliance work and upgrade projects.	Shopify Plus subscription, apps and any custom app or integration development.

Specialist auto parts retailer, in business since 1978
Legacy custom PHP platform to Shopify Plus
3 custom apps
Timeline:
About 12 months
Read the case study
Digital products brand for educators, USA
Custom platform to Shopify
1,430 digital products
Timeline:
4 to 5 weeks
Read the case study
Nonprofit educational ministry, USA
Headless React storefront to Shopify native theme
8 integrations kept
Timeline:
8 to 12 weeks
Read the case study

Custom platform to Shopify Plus migration FAQ

Can you migrate a custom built PHP, .NET or Java store to Shopify?

Yes. The language your store was written in matters less than where the data lives. We extract from your database or API, transform the data in staging, and load it into Shopify, then rebuild the storefront and business rules on Shopify.

How do you get data out of a custom database?

Usually with read only SQL exports or a database replica, using queries written for your schema. Where rules live in an API layer, we extract through your API instead. Large volumes are loaded into Shopify with GraphQL Admin API bulk imports (Shopify developer docs).

Should we stay headless after moving to Shopify?

Only if it still pays off. A Liquid theme has the lowest running cost and lets marketers edit pages without developers. Headless with Hydrogen or the Storefront API suits stores that need a fully custom experience and have developers to maintain it.

What are Hydrogen and Oxygen?

Hydrogen is Shopify’s framework for headless storefronts, built on React Router. Oxygen is Shopify’s hosting for Hydrogen storefronts, available at no extra charge on paid Shopify plans including Plus (Shopify developer docs).

Can Shopify handle our custom pricing, shipping and checkout rules?

In most cases, yes. Shopify Functions customize discounts, cart lines, delivery and payment options, validation and fulfillment. Only Shopify Plus stores can use custom apps that contain Shopify Function APIs (Shopify developer docs), so custom logic is a common reason to choose Plus.

How do our product attributes fit Shopify’s variant limits?

Shopify allows up to three options and 2,048 variants per product (Shopify Help Center). Attributes that create SKUs become options. Other attributes become typed metafields, and lookup tables such as brands or size charts become metaobjects.

Will we lose SEO when moving from a custom platform?

Not if every old URL gets a 301 redirect to its new Shopify URL and your titles, descriptions and content stay the same. Shopify Plus stores can hold up to 20,000,000 redirects, but URLs with query strings might not redirect as expected (Shopify Help Center), so we test each one.

Can our ERP, PIM, OMS and WMS connect to Shopify?

Yes. Each one connects through the Shopify Admin API and webhooks, using an existing connector where one fits, middleware, or a custom app we build. We agree which system owns each field before launch so data never conflicts.

Can historical orders and customer passwords be moved?

Orders, yes: they are imported through the API or a migration app, since admin CSV import covers products and customers only (Shopify Help Center). Passwords, no, because they are stored as hashes. With new customer accounts, customers sign in with a one time 6 digit code (Shopify Help Center).

How long does a custom platform to Shopify Plus migration take?

Typically 6 to 10 weeks for a simple custom store, 10 to 16 weeks for a mid market platform, and 16 to 28 weeks for enterprise, B2B or headless projects. These are typical ranges, not a guarantee. Your audit sets the actual schedule.

Book your custom platform to Shopify Plus migration audit

Ecomzier has built 1,100+ Shopify stores that have generated $500M+ in client revenue, backed by 11 eCommerce awards and 400+ five star reviews. Start with a free audit of your custom platform and a try before you buy demo of your store on Shopify Plus.

All Migration Services