ChatGPT answers, unedited

If your main business is building custom integrations for clients, I’d look first at Medusa.

Why Medusa fits a freelance integration shop

Medusa is built around a modular architecture rather than treating the store as a giant monolith. Its current architecture gives you:

• Custom modules for client-specific domains and third-party integrations.
• Workflows for multi-step business logic, including rollback/data consistency.
• API routes, subscribers, scheduled jobs, and admin extensions inside plugins.
• Access to the underlying commerce modules—products, orders, customers, inventory, payments, fulfillment, etc.—from your custom code.
• Reusable plugins/modules that you can carry from one client project to another. Medusa Docs Medusa Docs Medusa Docs

That last point is particularly attractive for a freelancer. You could, for example, build your own reusable integration package for an ERP, PIM, shipping provider, or CRM and deploy it across multiple client stores.

How I'd think about the main options

Saleor is also very extensible, but its model is more deliberately API/app oriented: its documentation emphasizes GraphQL, apps, webhooks, and extending the dashboard. Saleor Documentation

Medusa, by contrast, lets your custom code live directly in the application architecture. Its modules can define their own models/services, and workflows can combine those custom modules with Medusa's built-in commerce modules. Medusa Docs Medusa Docs

For a freelance developer, I'd choose based on stack

If you're primarily TypeScript/Node → Medusa.

If you're primarily Python/Django/GraphQL → Saleor.

If you're primarily PHP/Symfony → Sylius.

If you're primarily PHP/Laravel → Bagisto.

If your clients mostly want "WordPress + ecommerce + whatever plugin does it" → WooCommerce.

The interesting distinction is that WooCommerce may be the easiest to extend in terms of sheer ecosystem, whereas Medusa is arguably the cleaner starting point when your actual product is custom engineering. Current comparisons likewise distinguish WooCommerce's enormous extension ecosystem from Medusa's more developer-oriented modular architecture. OSSAlt OpenReplay Blog

For your particular business model, I'd seriously consider standardizing on Medusa + Next.js + PostgreSQL + Redis and building a small internal library of reusable integration modules. Medusa's own docs explicitly support reusable plugins containing modules, workflows, API routes, subscribers, scheduled jobs, and admin extensions. Medusa Docs Medusa Docs

If you tell me what kinds of integrations your clients typically need (ERP, Shopify migration, Stripe, shipping, PIM, marketplaces, subscriptions, B2B pricing, etc.), I can compare Medusa vs Saleor vs Sylius specifically for those workloads.

For a freelance developer doing custom integrations across many client stores, I’d look hardest at Medusa and WooCommerce, with Saleor as a strong option if you prefer an API-first/headless architecture.

My practical breakdown

🥇 Medusa — probably the most interesting for your use case

Medusa is specifically designed around customization. You can create modules, data models, API routes, workflows, event subscribers, scheduled jobs, admin extensions, and plugins rather than having to bolt everything onto an existing monolith. Medusa Docs Medusa Docs

The particularly useful part for client work is that integrations can become reusable modules/plugins. For example, you could build an ERP connector once and reuse it across multiple client projects. Medusa's plugins can package modules, workflows, API routes, hooks, subscribers, scheduled jobs, and admin extensions. Medusa Docs

Its architecture also explicitly supports third-party integrations through modules and workflows, including cross-system operations such as ERP synchronization. Medusa Docs

If you're comfortable with TypeScript/Node, I'd seriously consider making Medusa your default custom-commerce stack.

🥈 WooCommerce — easiest if clients want conventional WordPress stores

WooCommerce is extremely extensible from a developer's perspective. You have PHP hooks, filters, APIs, custom payment gateways, shipping methods, REST APIs, webhooks, and the entire WordPress ecosystem. The WooCommerce Developer Blog The WooCommerce Developer Blog

Its REST API covers things like products, orders, customers, coupons, and shipping zones, while webhooks can notify external systems about store events. The WooCommerce Developer Blog The WooCommerce Developer Blog

The advantage for a freelancer is client familiarity: many businesses already have WordPress hosting, WordPress skills, and WooCommerce experience.

The downside is architectural complexity. A heavily customized WooCommerce installation can eventually become a collection of plugins, hooks, theme overrides, and WordPress-specific behavior that you have to maintain.

🥉 Saleor — excellent for API-first/headless projects

Saleor takes a different approach: instead of modifying the core, you extend it with apps and APIs. Its backend is API-only, and its extensibility model includes webhooks, metadata, apps, API extensions, and dashboard extensions. GitHub Saleor Commerce

That makes it attractive when your typical client says:

"We have an ERP, PIM, CRM, custom frontend, warehouse system and several external services. Make them all work together."

Saleor also supports self-hosting and lets you build integrations in essentially any language because you're interacting through GraphQL rather than directly with its Python core. Saleor Commerce

What I'd choose as a freelancer

If your business is primarily "I build custom commerce systems and integrations", rather than "I build WordPress websites that happen to sell things," I'd lean toward:

Medusa → default custom-commerce stack
WooCommerce → clients who specifically want WordPress
Saleor → clients wanting sophisticated headless/API-first commerce

The biggest reason I'd put Medusa first is reuse. You can turn solutions you build for client A into modules/plugins/workflows that accelerate client B, rather than repeatedly fighting the platform's extension points. Medusa Docs Medusa Docs

If you tell me your preferred stack (TypeScript, PHP, Python, etc.) and the kinds of integrations you usually build (ERP, Shopify migration, marketplaces, subscriptions, fulfillment, custom pricing, etc.), I can narrow this down considerably.

If your priority is “I want to take a client’s weird business requirement and implement it without fighting the platform,” I’d pick medusajs.com.

My ranking for a freelance developer

1. Medusa — my default recommendation

Medusa is particularly well suited to the kind of work you're describing. Its architecture explicitly separates API routes → workflows → modules → database, and custom modules can contain their own data models and business logic. Medusa Docs Medusa Docs

The important bit for a freelancer is that you aren't forced to build every integration as an external service. You can put things like:

• ERP synchronization
• custom pricing
• unusual fulfillment logic
• marketplace functionality
• custom payment providers
• customer-specific business rules
• scheduled jobs and event handlers

inside the Medusa application itself. Its workflows can orchestrate multiple systems, while modules provide the integration boundary. Medusa Docs

It also has a particularly nice reuse story: package a client's reusable functionality as a plugin containing modules, workflows, API routes, etc., then install that plugin into another client's Medusa project. Medusa Docs

For someone doing repeated client projects, that's a big advantage.

docs.medusajs.com

2. Vendure — arguably the closest competitor

If you're a TypeScript developer, I'd seriously evaluate vendure.io alongside Medusa.

Vendure's model is very plugin-centric: plugins can add entities, business logic, GraphQL API extensions, permissions, and Admin UI functionality. Vendure Vendure Vendure

That makes it excellent for a freelancer building repeatable vertical solutions.

I'd lean Vendure over Medusa if you particularly like GraphQL and want a more opinionated plugin architecture. I'd lean Medusa if you want maximum freedom and a more modular “commerce framework” feel.

3. Sylius — excellent if you're a PHP developer

sylius.com is extremely extensible because it's fundamentally a Symfony-based framework rather than a traditional monolithic store builder. Its plugin architecture is designed specifically for extending functionality without modifying core code. Sylius Academy

If you're already strong in Symfony/PHP, I wouldn't dismiss it just because Medusa is trendy. For deeply customized B2B/enterprise projects, Sylius can be an excellent choice.

4. Saleor — great API, slightly different philosophy

saleor.io is attractive if you want GraphQL everywhere and prefer integrations to live primarily as apps/extensions. Its documentation has dedicated concepts for apps, dashboard extensions, custom modeling, payments, channels, etc. Saleor Documentation

I'd choose it when a client's requirements are particularly multi-channel / international / B2B rather than simply “we need lots of custom code.”

5. WooCommerce — easiest to sell, not necessarily easiest to architect

woocommerce.com remains compelling because its ecosystem is enormous. Its extension model gives you PHP hooks, REST APIs, webhooks, Store API extensions, payment APIs, shipping APIs, etc. The WooCommerce Developer Blog The WooCommerce Developer Blog

But there's a catch: you're extending WordPress + WooCommerce, so sufficiently unusual requirements can turn into wrestling with WordPress conventions, plugin interactions, update compatibility, and legacy APIs. WooCommerce itself warns that relying on internal APIs can cause extensions to break during updates. The WooCommerce Developer Blog

So I wouldn't choose WooCommerce purely because “it's easy to extend.”

What I'd use in your position

I'd standardize around:

Medusa + PostgreSQL + TypeScript + Next.js

and build your own reusable layer of:

/client-project
  /src
    /modules
      erp/
      custom-pricing/
      shipping/
      loyalty/
    /workflows
    /api
    /subscribers
  /plugins
    your-reusable-integrations

That gives you a useful flywheel: client #1 pays you to build an integration → you package the generalized version → client #2 becomes substantially faster.

Medusa's current architecture is explicitly designed around this sort of customization and reuse. Medusa Docs Medusa Docs

Bottom line: If you're primarily a JS/TS freelancer doing bespoke integrations, I'd start with Medusa, with Vendure as the alternative I'd benchmark before committing. If you're PHP/Symfony-native, choose Sylius instead.

If your main business is building custom integrations for clients, I’d put Medusa at the top of the list.

My ranking for a freelance developer

Why I'd choose Medusa

Medusa is particularly well suited to the agency/freelancer building lots of different integrations model.

Its architecture explicitly separates API routes → workflows → modules → database, and third-party services are designed to be integrated through replaceable modules. Medusa Docs Medusa Docs

For example, you can make a client-specific integration as a module, then reuse it across future projects. Medusa's plugin system can package modules, API routes, workflows, subscribers, scheduled jobs, links, and admin extensions into reusable packages. Medusa Docs Medusa Docs

That maps very nicely to integrations like:

• ERP ↔ ecommerce
• custom fulfillment providers
• unusual payment gateways
• inventory synchronization
• CRM/customer synchronization
• marketplace integrations
• custom pricing logic
• subscription systems
• PIM integrations
• bespoke B2B workflows

The fact that it's TypeScript/Node.js also makes it particularly attractive if you're already comfortable in the modern JS/TS ecosystem.

Where WooCommerce wins

WooCommerce is arguably the safer choice if your clients need a conventional WordPress site and you want the largest possible ecosystem of existing extensions.

The tradeoff is that you're extending a WordPress/PHP system rather than a commerce backend designed around modular services. Its enormous plugin ecosystem can save you tremendous development time, but customizations can also become entangled with WordPress themes, plugins, hooks, and upgrades.

So I'd use WooCommerce when the client says:

"We need a normal website/store, preferably WordPress, and there are probably plugins for most of this."

I'd use Medusa when they say:

"We have an ERP/PIM/warehouse/payment system and need ecommerce to fit around it."

Bagisto is worth serious consideration

Bagisto is the one I'd investigate if you work heavily in Laravel/PHP.

Its developer documentation explicitly supports creating packages/modules, custom shipping methods, payment methods, product types, REST/GraphQL APIs, and headless storefronts. Bagisto

That makes it surprisingly attractive for bespoke client work, especially if your clients are already Laravel shops.

Saleor

Saleor is excellent technically, particularly if you like Python + GraphQL. Its extension model includes apps, dashboard extensions, webhooks, custom modeling, and payment integrations. Saleor Documentation

I'd choose it over Medusa when the project has substantial multi-channel, multi-region, B2B, or enterprise commerce requirements and the team is comfortable with its architecture.

The important distinction

For your particular business, I'd optimize for "how quickly can I build integration #7 after I've built integrations #1–6?", rather than simply "which platform has the most features?"

On that criterion, my pick is:

1. Medusa → best overall for custom integration work
2. WooCommerce → best when the existing ecosystem solves the problem
3. Bagisto → best Laravel-oriented alternative
4. Saleor → best for sophisticated GraphQL/Python commerce
5. Magento → only when the client's requirements justify its complexity

One especially compelling Medusa feature for a freelancer is that modules can be reused across Medusa projects, while plugins let you package broader reusable customizations. Medusa Docs Medusa Docs

So you could gradually build your own internal library of, say, medusa-erp-sync, medusa-custom-shipping, medusa-b2b-pricing, etc., and reuse those components across clients.

If I were starting a freelance ecommerce integration practice today, I'd probably standardize on Medusa + Next.js + PostgreSQL, while keeping WooCommerce as the "client already uses WordPress" option.

If your main business is building custom stores for clients and integrating third-party systems, I’d shortlist Vendure and Medusa, with Vendure as my default pick for a freelance/agency workflow.

My ranking

1. Vendure — best overall for custom client work
2. Medusa — best if you want maximum flexibility and a lighter architecture
3. Saleor — best when GraphQL/Python/enterprise requirements dominate
4. WooCommerce — easiest ecosystem, but less pleasant for deeply custom headless work

Why I’d pick Vendure

Vendure is unusually well suited to the "every client needs something weird" scenario.

Its plugin system is essentially the extension mechanism for the entire platform. A plugin can:

• add/modify database entities
• add GraphQL queries and mutations
• add custom fields
• integrate external systems
• react to commerce events
• run background jobs
• modify configuration and existing behavior

That's all explicitly supported by the framework rather than requiring you to fork the core. Vendure GitHub

For example, you could make reusable plugins such as:

your-agency/
├── vendure-plugin-erp/
├── vendure-plugin-custom-pricing/
├── vendure-plugin-shipping-provider/
├── vendure-plugin-crm-sync/
├── vendure-plugin-b2b/
└── vendure-plugin-marketplace/

Then reuse those across clients.

The other big advantage is that it's TypeScript + NestJS + GraphQL, so you get a fairly conventional dependency-injection/module architecture instead of inventing your own extension conventions. GitHub

Medusa is a very close second

Medusa is arguably more attractive if you're a TypeScript/Node developer who wants the platform to behave more like a commerce toolkit than a traditional ecommerce application.

Its current architecture has modules, workflows, subscribers, scheduled jobs, API routes and admin extensions. Those can all be packaged into reusable plugins. Medusa Documentation Medusa Documentation

The particularly nice part for integrations is its workflow system. You can compose existing commerce workflows into your own workflows and add custom steps, including compensation/rollback behavior. Medusa Documentation

So something like:

Order placed
    ↓
Create ERP order
    ↓
Reserve inventory
    ↓
Create shipment
    ↓
Send CRM event

can be modeled as application workflows rather than a pile of webhook handlers.

I'd choose Medusa over Vendure if your clients routinely need complex multi-system orchestration.

Where Saleor fits

Saleor is excellent, but I'd choose it more selectively.

It's GraphQL-first and has a strong concept of external apps, webhooks, dashboard extensions, channels, etc. Saleor Documentation

That makes it attractive for larger/enterprise clients and teams already comfortable with Python/Django + GraphQL.

But if your question is specifically:

"I get a new client with a strange requirement. Which platform lets me jump into the backend and implement it?"

I'd rather have Vendure or Medusa.

The important distinction

I'd think about them like this:

One caveat: check licensing carefully for the exact version/components you deploy rather than assuming the entire ecosystem has one license. Current third-party comparisons sometimes disagree on license details, so I'd verify against the project's own repository/docs before standardizing your agency stack. GitHub ShipGarden

What I'd do if I were building an agency stack

I'd probably standardize on Vendure + Next.js + PostgreSQL.

Build your own internal layer of reusable Vendure plugins:

Core
├── ERP connector
├── Accounting connector
├── CRM connector
├── Shipping abstraction
├── Payment integrations
├── Custom pricing
├── B2B organizations
├── Product import/export
├── Client-specific webhooks
└── Audit/event logging

Then each new client becomes mostly configuration + composing your existing plugins, rather than starting an ecommerce backend from scratch.

That is where Vendure's architecture really pays off for a freelancer: its official documentation explicitly positions plugins as the place for custom business logic and integrations, including CMS synchronization. Vendure Vendure

Bottom line: if "easy to extend" means I want to build arbitrary custom commerce behavior without fighting the platform, I'd start with Vendure. If "easy to extend" means I want a highly composable commerce engine and sophisticated integration workflows, I'd seriously consider Medusa.

If your main business is building custom stores for clients and integrating ERP/CRM/PIM/payment/fulfillment systems, I’d put Medusa at the top of the list.

My ranking for a freelance developer

1. Medusa — best overall for custom integrations
2. Saleor — best API/headless architecture
3. WooCommerce — easiest if clients want WordPress
4. Sylius — extremely flexible, but higher development overhead

Why I'd choose Medusa

Medusa is unusually well suited to the "client needs something weird" freelance model. Its architecture explicitly revolves around modules, workflows, API routes, data models, events, and third-party integrations. You can create a module for an ERP/PIM/etc., then use workflows to orchestrate operations between it and the commerce system. Medusa Docs Medusa Docs

For example, a client might say:

"When an order is placed, reserve inventory in our ERP, send the order to our 3PL, calculate a custom shipping rate, and only then mark the order as ready for fulfillment."

That's very much the sort of thing Medusa's workflow/module architecture is designed to handle. Its workflows also provide rollback/reliability mechanisms rather than requiring you to glue everything together with ad-hoc webhooks. Medusa Docs Medusa Docs

It also lets you add your own data models and connect them to existing commerce models without tightly coupling everything together. Medusa Docs Medusa Docs

And importantly for a freelancer, you can potentially reuse your modules across different client projects. Medusa Docs

docs.medusajs.com

Where Saleor fits

I'd pick Saleor instead if you prefer a strongly headless/API-first architecture and expect your integrations to live as separate services.

Saleor is GraphQL-native and has extensive webhooks, apps, dashboard extensions, and mechanisms for extending the commerce model. Saleor Commerce Saleor Documentation

The tradeoff is that Medusa feels more like a commerce framework you customize internally, whereas Saleor feels more like a commerce engine you compose around.

For a solo developer who is repeatedly implementing bespoke business logic, I find Medusa's approach more attractive.

Where WooCommerce fits

If the client's requirements are relatively conventional and they specifically want WordPress, WooCommerce is still incredibly practical.

Its plugin/hook ecosystem is enormous, and it has REST APIs plus customer-facing Store APIs. The WooCommerce Developer Blog The WooCommerce Developer Blog

The downside for your particular business is architectural: once clients start asking for deeply customized commerce behavior, you can end up navigating WordPress/WooCommerce hooks, plugin interactions, and compatibility boundaries. WooCommerce itself warns that internal APIs aren't guaranteed to maintain backwards compatibility. The WooCommerce Developer Blog

So I'd use WooCommerce when WordPress is part of the requirement, rather than making it my default custom-commerce platform.

The short version

If I were starting a freelance ecommerce practice today, I'd learn Medusa first. Its architecture maps unusually well to selling "custom integrations" as your differentiator rather than just selling website builds. Medusa Docs Medusa Docs

If you tell me your preferred stack (Node/TypeScript, PHP, Python, etc.) and the kinds of integrations your clients usually need, I can also give you a Medusa vs Saleor vs WooCommerce decision matrix specifically for freelance work, including maintenance burden and how easy it is to reuse your integration code across clients.

If your main business is building custom stores for clients and integrating ERPs, CRMs, PIMs, fulfillment systems, unusual pricing logic, marketplaces, etc., I’d shortlist Vendure and Medusa.

My pick: Vendure

Vendure is probably the easiest fit if your priority is deep customization without fighting the platform.

Its plugin system is unusually comprehensive: plugins can add database entities, GraphQL fields/resolvers, external integrations, event handlers, background jobs, and custom fields. Vendure Vendure

The big advantage for a freelance developer is that you're essentially extending a NestJS/TypeScript application, rather than learning a proprietary extension language.

Vendure vs. Medusa

This is the comparison I'd make most seriously.

Choose Vendure if:

• You like NestJS/TypeScript.
• You want a conventional, structured backend.
• You frequently need to alter core commerce behavior.
• You want plugins to have direct access to the application and database.
• You're building fairly different stores for different clients.

Vendure itself describes the architecture as a single NestJS application where catalog, pricing, orders, customers, channels, APIs, and extensions live together. Vendure

Choose Medusa if:

• You prefer a more composable/modular architecture.
• Your integrations tend to be external systems that need orchestration.
• You want reusable modules across client projects.
• You like its workflow/rollback model.

Medusa has first-class modules, workflows, API routes, subscribers, scheduled jobs, and admin extensions. Its docs specifically position custom modules as the way to integrate external systems such as ERPs and CMSs. Medusa Docs Medusa Docs Medusa Docs

For a freelancer, that last part is particularly attractive: you could build something like a reusable AcmeERPModule once and carry the pattern between projects.

Where Saleor fits

Saleor is excellent, but I'd rank it slightly lower for your particular use case.

Its extension philosophy is deliberately "don't modify the core; build apps around it." Apps communicate through GraphQL and webhooks. That's excellent for keeping upgrades safe and allowing integrations to be written in virtually any language. Saleor Commerce Saleor Commerce

But if a client says:

"We need checkout to behave completely differently and we need custom business logic inside the commerce engine."

I'd rather be holding Vendure or Medusa.

The important distinction

I'd actually categorize them like this:

• Vendure: "Give me a commerce backend and let me program it."
• Medusa: "Give me commerce primitives and let me assemble/customize the system."
• Saleor: "Give me a stable commerce API and let me build integrations around it."
• WooCommerce: "Give me WordPress + an enormous plugin ecosystem and let me bend it to my will."

For a freelance developer doing bespoke integrations repeatedly, I'd start with Vendure, with Medusa as the other serious candidate.

If you tell me the kinds of integrations you typically build (ERP, Shopify migration, custom payment, subscriptions, PIM, shipping, B2B pricing, marketplaces, etc.), I can give you a more opinionated Vendure vs Medusa vs WooCommerce vs Saleor recommendation based on actual implementation effort.

But if a client says:

"We need checkout to behave completely differently and we need custom business logic inside the commerce engine."

I'd rather be holding Vendure or Medusa.

The important distinction

I'd actually categorize them like this:

If your main business is building custom stores and integrations for clients, I’d shortlist Medusa and Vendure, with Medusa as my default choice.

My ranking

1. Medusa — easiest for custom integrations
2. Vendure — best if you like NestJS/GraphQL
3. Saleor — excellent, especially for Python/GraphQL teams
4. Sylius — extremely flexible, but more framework-heavy

Why I'd pick Medusa

Medusa is designed almost like a commerce backend framework, rather than a finished monolithic shop that you have to fight against.

Its architecture gives you:

• Modules for custom domains and third-party integrations
• Workflows for multi-step business processes and rollback
• API routes for exposing your own functionality
• Subscribers/events for reacting to commerce events
• Custom data models
• Admin extensions
• Reusable plugins containing combinations of all of the above Medusa Docs Medusa Docs

That maps unusually well to freelance work. For example, a client might say:

"When an order ships, push it to our ERP, update our warehouse, send data to our CRM, and create a loyalty transaction."

In Medusa, that naturally becomes an integration module + workflow + event/subscriber rather than modifications scattered throughout the ecommerce core. Medusa explicitly documents this pattern for third-party systems. Medusa Docs

It also means you can build your own reusable modules once and carry them between clients.

Vendure is a very close second

If you're a TypeScript/NestJS developer, I'd seriously consider Vendure.

Its plugin system is exceptionally straightforward: a plugin can add database entities, REST controllers, GraphQL queries/mutations, custom fields, external integrations, event handlers, background jobs, and configuration. Vendure Vendure

That's arguably even more intuitive than Medusa if your integrations tend to look like conventional backend development.

For example:

Client store
├── ERPPlugin
├── ShippingPlugin
├── CRMPlugin
├── CustomPricingPlugin
└── MarketplacePlugin

Each can encapsulate its own entities, services, API extensions and integration logic.

Vendure also has a very nice strategy/plugin architecture for replacing specific pieces of behavior without modifying the core. Vendure

The practical distinction

What I'd actually do as a freelancer

I'd choose Medusa if you're starting a new client platform today, particularly if your stack is already TypeScript/Node/Next.js.

The killer feature isn't really its ecommerce functionality. It's that you can treat the platform as infrastructure for composing a client's commerce system. Medusa itself describes its modules as usable as a middleware layer between commerce systems, which is almost exactly your use case. Medusa Docs Medusa Docs

I'd choose Vendure instead if you already know NestJS well or expect clients to require lots of custom admin/API/domain behavior. Its plugin architecture is exceptionally clean. Vendure Vendure

One important consideration: don't choose purely on "how extensible is it?" For freelance client work, I'd also evaluate license, upgrade friction, hosting/deployment, admin customization, multi-store/multi-channel requirements, and how easy it is to hand the project over to another developer. Those can matter more than raw extensibility.

If you tell me your typical client integrations (e.g. ERP + Shopify migration + Stripe + shipping + subscriptions + PIM + custom pricing), I can give you a much more concrete Medusa vs Vendure vs Saleor recommendation and a suggested architecture for your freelance stack.

If your main business is building custom stores and integrations for clients, I’d pick Medusa.

My ranking for a freelance developer

Why I'd choose Medusa

Medusa is unusually well suited to the kind of work you're describing. Its architecture treats custom functionality as a first-class concept: you can create custom modules, API routes, workflows, data models, module links, event subscribers, and integrations rather than fighting a monolithic plugin system. Medusa Docs Medusa Docs

The particularly useful part for client work is the integration model:

third-party service → module → workflow → API/event

So, for example, if a client has an ERP, PIM, warehouse, subscription system, or unusual pricing engine, you can make a module for it and then orchestrate synchronization through workflows. Medusa explicitly supports this pattern for systems such as ERPs and CMSs. Medusa Docs Medusa Docs

It also uses TypeScript/Node.js, which makes it attractive if you're already comfortable with the modern JS ecosystem.

One particularly nice architectural feature is module links: you can associate your custom entities with Medusa's commerce entities without directly coupling your module's database models to theirs. Medusa Docs

The big caveat: WooCommerce

If by "easiest to extend" you mean "I want a plugin for almost anything a client might ask for", then WooCommerce wins.

Its enormous WordPress/plugin ecosystem means you can frequently avoid writing an integration yourself. WP Bundle

But there's a difference between:

• extending an existing ecosystem, and
• building a custom commerce application

For the latter, I think Medusa is substantially cleaner.

When I'd choose Sylius instead

I'd seriously consider Sylius if you're a strong PHP/Symfony developer and your clients tend to have complicated B2B/business rules.

It's particularly compelling when the store itself is basically a custom application with commerce functionality, rather than a conventional ecommerce site.

My practical recommendation

For a freelance consultancy, I'd probably standardize around:

Medusa + Next.js + PostgreSQL + your preferred CMS + Stripe/etc.

Then build your own reusable modules for things you repeatedly encounter:

• ERP connectors
• PIM synchronization
• custom pricing
• B2B accounts
• shipping providers
• tax integrations
• marketplace feeds
• inventory synchronization
• customer-specific catalogs
• custom checkout logic

That lets you turn each new client project into configuration + incremental development rather than starting from zero. Medusa explicitly supports reusing custom modules across projects. Medusa Docs

Bottom line: If you're selling custom integrations and bespoke commerce development, I'd start with Medusa. If you're selling fast implementation of conventional stores, I'd choose WooCommerce.

If you tell me your typical clients (B2B/B2C, order volume, ERP/PIM systems, preferred language, and whether you use React), I can narrow this down to Medusa vs Sylius vs WooCommerce for your specific business model.

It also uses TypeScript/Node.js, which makes it attractive if you're already comfortable with the modern JS ecosystem.

One particularly nice architectural feature is module links: you can associate your custom entities with Medusa's commerce entities without directly coupling your module's database models to theirs.

The big caveat: WooCommerce

If your priority is “I’m a developer and every client may need weird custom integrations”, I’d pick Medusa.

My ranking

Why I'd choose Medusa

Medusa is essentially designed around the problem you're describing. Its architecture separates API routes → workflows → modules → database, and those layers themselves can be implemented in plugins. More importantly, you can create custom modules for your client's external systems rather than hacking the core. Medusa Docs Medusa Docs

For example, imagine a client needs:

• ERP synchronization
• custom pricing from an external API
• unusual fulfillment logic
• Stripe + another payment provider
• inventory from their warehouse system
• CRM/customer synchronization
• custom B2B rules
• webhook/event-driven integrations

You can make those into reusable modules/workflows and carry the patterns into your next client project. Medusa explicitly supports custom commerce and infrastructure modules, including payment, fulfillment, notification, event, file, caching, and other integrations. Medusa Docs Medusa Docs

It's also a particularly good fit if you're comfortable with TypeScript/Node.js and building the storefront separately. The storefront is decoupled from the Medusa application, so you can use whatever frontend stack makes sense for the client. Medusa Docs

docs.medusajs.com

When I'd choose something else

Sylius would be my alternative if you're a strong PHP/Symfony developer and expect clients to require very deep domain-level customization. It's more of a commerce framework than a turnkey store, which can actually be an advantage for an agency/developer.

Saleor is excellent if you want GraphQL-first development. Its extension model uses apps, webhooks, API extensions, metadata, and dashboard extensions rather than a traditional monolithic plugin architecture. GitHub GitHub

saleor.io

WooCommerce is the choice I'd make when the client specifically benefits from WordPress and its enormous existing ecosystem. It isn't necessarily the cleanest engineering architecture for novel integrations, but the sheer number of existing plugins can dramatically reduce implementation time.

For a freelance developer specifically

I'd optimize for reusability across clients, not just how easy it is to modify one store.

That makes my preferred stack:

Medusa + PostgreSQL + Redis + Next.js + your own reusable integration modules

You could build your own internal modules for things like:

/integrations
  /stripe
  /shopify-import
  /quickbooks
  /netsuite
  /shipstation
  /custom-erp

/modules
  /b2b-pricing
  /customer-credits
  /subscriptions
  /custom-products

/workflows
  /sync-order-to-erp
  /fulfill-order
  /import-catalog

Then each new client becomes more configuration and composition rather than starting from zero.

Bottom line: If you're deliberately positioning yourself as the developer who builds custom-integrated ecommerce, I'd start with Medusa. If you're a PHP/Symfony specialist, I'd seriously consider Sylius instead. If your clients skew toward sophisticated GraphQL/multichannel/enterprise requirements, Saleor deserves a close look.

If your priority is “I need to build weird, client-specific integrations without fighting the platform,” I’d pick Medusa first.

My ranking for a freelance developer

Why I'd choose Medusa

Medusa is essentially designed around the scenario you're describing: a commerce engine that developers customize rather than a rigid store builder. Its current architecture gives you API routes, workflows, custom data models/modules, event subscribers, scheduled jobs, admin customization, and integrations as first-class extension points. Medusa Docs Medusa Docs

The particularly useful part for client work is its module system. You can create a custom module for something like:

• ERP synchronization
• B2B companies and purchasing rules
• custom pricing
• warehouse/inventory systems
• subscription logic
• bespoke fulfillment
• external PIM/CMS integration
• client-specific business entities

…and have that functionality live inside the same application rather than maintaining a completely separate integration service. Medusa explicitly supports custom modules and replacing providers for things such as payments, fulfillment, notifications, storage, events, and infrastructure. Medusa Docs Medusa

It also has a workflow layer, which is valuable when you're doing integrations where multiple systems have to change atomically or reliably. Medusa Docs

When I'd pick the others

Sylius would be my choice if you're a strong Symfony/PHP developer and expect extremely bespoke business rules. It's arguably one of the most flexible traditional commerce frameworks, but the Symfony ecosystem means a steeper initial investment than Medusa.

Saleor is excellent if you want an API-only, GraphQL-first architecture and prefer keeping custom functionality in separate apps. Its extension model revolves around APIs, webhooks, metadata, apps, and dashboard extensions. Saleor Documentation GitHub

The distinction I'd make is:

Medusa: “Customize the commerce application itself.”
Saleor: “Build applications around the commerce API.”

For a freelancer doing many different clients, I slightly prefer the former because you can build reusable modules/workflows and carry them from project to project.

WooCommerce is still the pragmatic choice when the client already lives in WordPress or needs a huge ecosystem of existing plugins. But for genuinely custom commerce architecture, I'd rather start with Medusa than progressively turn WooCommerce into an application framework.

My recommendation

If your typical project looks like:

Next.js storefront → commerce backend → Stripe + ERP + shipping + custom client logic + third-party APIs

I'd start with Medusa.

If it looks like:

Symfony/PHP application → highly bespoke B2B/marketplace/business rules

I'd seriously consider Sylius.

If it looks like:

Headless frontend → GraphQL commerce API → lots of independently deployed integrations/apps

I'd consider Saleor.

For a freelance developer, Medusa is probably the best balance of extensibility, developer experience, and ability to turn your custom integrations into reusable building blocks. Medusa Docs Medusa Docs

If you tell me your preferred stack (Node/TS, PHP, Python, etc.) and the kinds of integrations your clients usually request, I can narrow this down to a specific platform and architecture.

If your main business is building custom stores for clients and integrating ERPs, CRMs, fulfillment systems, PIMs, custom payment flows, etc., I’d shortlist Medusa and Vendure, with Vendure as my pick for “easiest to extend” if you’re comfortable with TypeScript/NestJS.

My ranking for a freelance developer

1. Vendure — my pick

Vendure is almost purpose-built for what you're describing. Its plugin architecture lets you:

• add custom database entities
• add/modify GraphQL queries and mutations
• create REST endpoints
• inject your own services
• respond to events such as orders being placed
• run background tasks
• interact directly with external systems
• add custom fields
• customize the Admin UI

All of that is exposed through its plugin system rather than requiring you to fork the core. Vendure Developer Hub Vendure Developer Hub

The architecture is also very familiar if you're a TypeScript developer: Node.js + NestJS + GraphQL + TypeORM.

That makes something like:

"When an order is paid, send it to the client's ERP, reserve inventory, create a shipment, and expose the ERP status in Admin"

feel like a normal application feature rather than an awkward ecommerce hack.

2. Medusa — extremely close second

I'd choose Medusa if you prefer a more modular/composable architecture.

Medusa has explicit modules for things like products, orders, inventory, payments, fulfillment, regions, pricing, etc., and lets you create custom modules and workflows. Its architecture is specifically designed around replacing/integrating third-party services. Medusa Documentation Medusa Documentation

Its plugins can package modules, API routes, workflows, workflow hooks, links, subscribers, scheduled jobs, and Admin extensions, which is particularly attractive for a freelancer because you can turn integrations you've built for one client into reusable packages. Medusa Documentation

I'd actually lean Medusa over Vendure if your long-term goal is:

"I want to build my own reusable commerce/integration framework on top of an ecommerce engine."

The important distinction

I'd think about them this way:

Vendure:
"Here's a really good ecommerce application; extend it with TypeScript plugins."

Medusa:
"Here's a commerce framework; compose and replace pieces to build the system you want."

For client work, both are substantially nicer than fighting against a SaaS platform's extension boundaries.

What I'd use for your freelance business

If you're primarily a TypeScript/Node developer, I'd start with:

Vendure → default choice
Medusa → use when the project is particularly composable/integration-heavy

I'd also avoid Saleor unless you specifically want Python/Django. Saleor is very capable and has a strong GraphQL/app-extension model, but its Python stack means you're giving up some of the simplicity of staying entirely in the TypeScript ecosystem. Saleor Documentation

One other consideration is licensing: before standardizing on either platform for client projects, I'd have your lawyer/accountant check the current licenses and how they apply to the way you're distributing/customizing deployments.

If you tell me your preferred stack (TypeScript/PHP/Python), typical client size, and the integrations you build most often, I can give you a much more concrete Vendure vs Medusa vs WooCommerce recommendation for a freelance agency setup.

If your priority is “I’m a developer, and every client may need weird custom integrations”, I’d shortlist these:

My pick: Medusa

For a freelance developer doing bespoke integrations, I'd lean toward Medusa.

Its architecture is explicitly designed around customization: API routes → workflows → modules → database, and third-party integrations can be implemented as custom modules. You can also package reusable customizations as plugins and reuse them across client projects. Medusa Docs Medusa Docs Medusa Docs

That maps nicely onto freelance work:

• Client needs an ERP integration → custom module + workflow.
• Client needs unusual pricing → customize the pricing domain/workflow.
• Client needs a proprietary fulfillment provider → fulfillment module.
• Client needs custom admin functionality → admin extension.
• You solve the same problem for another client → turn it into a reusable plugin.

It's particularly attractive if you're comfortable with TypeScript/Node.

When I'd choose Shopware instead

If clients expect a more traditional, batteries-included ecommerce platform, I'd seriously consider Shopware.

Its self-hosted version has PHP/Symfony plugins that can intervene deeply in the platform, alongside apps and APIs. Shopware explicitly positions plugins as the mechanism for deep customization of self-hosted stores. Shopware Shopware

That's a particularly good fit if you're doing things like:

• complicated B2B pricing
• ERP/PIM integrations
• custom checkout logic
• unusual product/catalog rules
• complex promotions
• custom administration functionality

Shopware also has a mature integration model for connecting external systems through APIs. Shopware Shopware Documentation

Sylius is the “developer's framework” choice

Sylius is worth considering if your clients' requirements are so custom that you're effectively building a bespoke commerce application.

The tradeoff is that you get more architectural freedom and less of the “install a plugin and configure it” experience. Its ecosystem has an official addons marketplace, but I'd choose it primarily because you want to build around Symfony/PHP, not because you want the quickest possible client deployment. Sylius Addons Marketplace

WooCommerce is underrated for freelancing

If your business model is “ship client stores quickly and make money on implementation”, WooCommerce may actually win.

Its PHP extension model is extremely mature, and it exposes APIs for products, orders, customers, shipping, payments, settings, etc. The WooCommerce Developer Blog The WooCommerce Developer Blog

The downside is architectural cleanliness: WordPress/WooCommerce can become messy when a project accumulates lots of bespoke business logic and integrations.

Saleor

I'd pick Saleor when the project is strongly headless/API-first. Its GraphQL API, app system, dashboard extensions, and commerce-domain modeling make it powerful for custom frontends and integrations. Saleor Documentation

But for general-purpose freelance work, I'd put Medusa/Shopware ahead of it.

My ranking for your specific business

If you're primarily a developer rather than an agency selling a packaged store:

1. Medusa — best modern custom-development experience
2. Shopware — best full-featured platform for deep customization
3. Sylius — best if you want a commerce framework rather than a conventional store
4. WooCommerce — best for speed, ecosystem, and smaller clients
5. Saleor — best for API/GraphQL-heavy headless projects

The key distinction I'd make is:

Medusa/Sylius let you build the commerce system around the client's requirements. Shopware/WooCommerce give you a commerce system and let you bend it to the client's requirements.

For a freelancer doing custom integrations repeatedly, I'd start with Medusa if you're TypeScript-first, or Shopware if you're PHP/Symfony-first.

Its PHP extension model is extremely mature, and it exposes APIs for products, orders, customers, shipping, payments, settings, etc. developer.woocommerce.com developer.woocommerce.com

The downside is architectural cleanliness: WordPress/WooCommerce can become messy when a project accumulates lots of bespoke business logic and integrations.

Saleor

I'd pick Saleor when the project is strongly headless/API-first. Its GraphQL API, app system, dashboard extensions, and commerce-domain modeling make it powerful for custom frontends and integrations.

But for general-purpose freelance work, I'd put Medusa/Shopware ahead of it.

My ranking for your specific business

If your priority is “I’m a developer, I need to bend the platform around each client’s weird integrations”, my first choice would be Medusa.

My ranking for a freelance integration-heavy shop

Why I'd pick Medusa

Medusa is unusually well suited to the freelancer building multiple bespoke stores model.

Its architecture explicitly separates API routes → workflows → modules → database, and custom third-party integrations can be implemented as modules. Medusa Docs Medusa Docs

That gives you a nice pattern like:

Client store
│
├── Core Medusa
│
├── Custom ERP module
├── Custom pricing module
├── Custom fulfillment provider
├── Custom CRM integration
├── Custom payment provider
│
└── Client-specific workflows

Even better, Medusa's plugins can bundle modules, API routes, workflows, subscribers, scheduled jobs, and admin extensions. So once you build an integration for Client A, you can turn the reusable portion into a package and use it for Client B. Medusa Docs

And the stack is TypeScript/Node, which makes it particularly attractive if you're already comfortable in the modern JS ecosystem.

docs.medusajs.com

Vendure is probably the closest alternative

I'd seriously consider Vendure if you want an even more opinionated TypeScript plugin architecture.

It's particularly attractive when your projects involve lots of:

• custom entities
• custom admin UI
• payment/shipping providers
• event-driven integrations
• bespoke checkout logic
• TypeScript-heavy codebases

For a developer, it's arguably one of the cleanest platforms to turn into a custom commerce application rather than merely customize an existing store.

Where Saleor fits

Saleor is excellent if you're comfortable with GraphQL and distributed integrations. Its API-first model uses apps, webhooks, API extensions, metadata, and dashboard extensions rather than a traditional monolithic plugin architecture. Saleor Documentation GitHub

That's powerful, but there's a philosophical difference:

Medusa:

“Extend the commerce application itself.”

Saleor:

“Build services/apps around an API-centric commerce core.”

For a freelance developer who frequently needs to implement unusual business logic inside the commerce system, I'd lean Medusa.

Sylius deserves a mention

If you're a strong PHP/Symfony developer, Sylius could actually be your best choice.

Its plugin architecture is mature and deeply integrated with Symfony, and plugins can add things such as payment gateways, CRM/ERP integrations, custom resources, forms, validation, grids, and more. Sylius Academy

The downside is that it assumes significantly more Symfony knowledge than Medusa assumes of a typical TypeScript developer.

What I'd use for your business

If I were setting up a freelance practice today:

Default: Medusa
TypeScript-heavy / highly structured: Vendure
PHP/Symfony specialist: Sylius
GraphQL/composable architecture: Saleor
“Client wants 500 existing plugins”: WooCommerce
Enterprise procurement / huge existing organization: Shopware or Magento

The important distinction is that Medusa/Vendure/Sylius are closer to commerce frameworks, whereas WooCommerce/Magento/Shopware are more like established commerce platforms that you customize.

For your particular business model, I'd favor the former: you want the platform to get out of your way rather than force your integration into somebody else's assumptions.

If you tell me your typical client integrations (ERP, Shopify migration, NetSuite, Stripe, shipping, subscriptions, B2B pricing, marketplaces, etc.), I can give you a Medusa vs Vendure vs Sylius comparison specifically for freelance client work, including which one is easiest to reuse across projects.

If your main business is building custom stores for clients, I’d put Medusa at the top of the list right now.

My ranking for a freelance developer

🥇 Medusa — probably your best fit

docs.medusajs.com

Medusa is particularly attractive for a freelancer because it is designed more like a commerce framework than a finished monolithic store. Its architecture gives you API routes, workflows, modules, events, data models, integrations, and admin extensions as explicit extension points. Medusa Docs Medusa Docs

The big advantage for client work is that you can turn your recurring integrations into reusable packages. Medusa plugins can contain modules, API routes, workflows, subscribers, scheduled jobs, and admin extensions, and can be published as npm packages. Medusa Docs Medusa Docs

So you could, for example, build:

client store
├── Medusa
├── ERP integration
├── custom pricing engine
├── shipping integration
├── CRM sync
└── your reusable agency plugins

And those integrations don't require hacking the core.

It's also a particularly natural choice if you're already comfortable with TypeScript/Node/React.

🥈 Sylius — fantastic if you're a PHP/Symfony developer

sylius.com

If PHP/Symfony is your preferred ecosystem, I'd seriously consider Sylius. It's extremely composable and its plugin architecture is mature. The official ecosystem has plugins for payments, shipping, CRM/ERP integrations, marketing, search, etc. Sylius Academy Sylius Addons Marketplace

I'd choose Sylius over Medusa when a client needs very deep domain-specific commerce logic, particularly B2B.

🥉 Saleor — excellent API-first alternative

docs.saleor.io

Saleor is compelling if you want a strongly headless, GraphQL-first architecture. Its extension model includes apps, webhooks, metadata, API extensions and dashboard extensions. Saleor Documentation GitHub

I'd lean Saleor when the integration architecture is mostly:

Saleor
   ↓ GraphQL
your application/services
   ↓
ERP / CRM / PIM / payments / fulfillment

rather than wanting to modify commerce behavior deeply inside the platform.

What I'd choose in your position

If you're a freelance JS/TS developer doing multiple custom ecommerce projects, I'd standardize on:

Medusa + Next.js + PostgreSQL + your own reusable integration modules.

That gives you a nice agency flywheel: the second time you integrate an ERP, payment provider, fulfillment system, custom pricing engine, etc., you're building on work from the previous client rather than starting over.

The key distinction is that WooCommerce is probably easiest to get a basic store running, but Medusa is easier to make into a genuinely custom commerce system without fighting the platform.

If you tell me what kinds of integrations your clients typically need (ERP, Shopify migration, marketplaces, subscriptions, B2B pricing, custom checkout, etc.), I can give you a more specific Medusa vs Sylius vs Saleor vs WooCommerce recommendation.

For a freelance developer building custom stores with lots of integrations, I’d usually rank them like this:

1. Medusa — easiest to extend for custom builds
2. WooCommerce — easiest to deliver quickly for mainstream merchants
3. Saleor — powerful, but better for larger/enterprise-style builds
4. Sylius — excellent if you are a PHP/Symfony specialist
5. Shopware — strong ecosystem, heavier stack

OpenReplay Blog WPBundle## My pick for a freelance integration specialist: Medusa

If your clients are asking for things like:

• ERP integrations
• custom pricing logic
• unusual checkout flows
• marketplace functionality
• subscription logic
• custom fulfillment rules
• external inventory systems
• bespoke admin workflows

I would lean toward Medusa.

Why:

• TypeScript end-to-end: your storefront, backend extensions, and integrations can all live in the same ecosystem.
• Modular architecture: payments, fulfillment, inventory, pricing, and other commerce concerns are designed to be replaced or extended rather than hacked around.
• Headless-first: you are not fighting a theme system or CMS assumptions.
• Clean deployments: a Node app + database is a simpler mental model than many older commerce stacks. WPBundle Eryx Innovations Lab

The downside: you will write more integrations yourself because its plugin ecosystem is much smaller than WooCommerce’s. WPBundle

When I would choose WooCommerce instead

Choose WooCommerce when the client says:

• "We need a store like this existing WordPress site."
• "We need lots of marketing pages."
• "We need a niche payment/shipping/tax plugin."
• "The client wants to manage everything themselves."

The advantage is not the architecture; it is the ecosystem. There are years of plugins, agencies, tutorials, and merchant familiarity behind it. WPBundle

The tradeoff: deep custom business logic can become WordPress/plugin-hook archaeology.

When Saleor makes sense

Saleor is attractive when clients need:

• multi-region catalogs
• multi-warehouse inventory
• complex B2B permissions
• GraphQL-first architecture

It is very capable, but the extension model is more API/app/webhook oriented rather than "drop in code and modify behavior." GitHub Netguru

My freelance stack recommendation

If I were building a reusable agency/freelance toolkit:

Default stack

• Backend: Medusa
• Frontend: Next.js
• Database: PostgreSQL
• CMS: Sanity/Contentful/Strapi when needed
• Payments: Stripe/Adyen/etc.
• Integrations: custom Medusa modules

Keep WooCommerce in your toolbox

Use it when the client values:

• fast launch
• WordPress editing
• existing plugins
• lower initial budget

A practical rule:

• 80% custom workflow/integration → Medusa
• 80% marketing site + normal store → WooCommerce
• enterprise catalog complexity → Saleor/Sylius

For a solo developer trying to build a repeatable custom-commerce practice, I’d invest in Medusa first and keep WooCommerce as the "ship it fast" option. WPBundle WPBundle

For a freelance developer doing custom integrations repeatedly across different client stores, I’d pick Medusa.

My ranking for your use case

Why I'd choose Medusa

The big advantage is that customization is part of the architecture rather than something you bolt onto the platform.

Medusa 2 gives you:

• Modules for your own data models and integrations.
• Workflows for multi-step business logic and cross-system operations.
• Workflow hooks for injecting behavior into existing commerce flows.
• API routes for exposing your own functionality.
• Subscribers/events for reacting to commerce events.
• Admin extensions for adding client-specific functionality to the admin.
• Plugins that package all of the above so you can reuse your work between clients. Medusa Docs Medusa Docs Medusa Docs

That's particularly attractive for a freelancer. For example, you could build:

my-medusa-integrations/
├── erp-sync/
├── custom-pricing/
├── shipping-provider/
├── crm-integration/
└── client-specific/

and turn the pieces that recur across projects into reusable packages. Medusa explicitly supports packaging modules, workflows, API routes, admin extensions, etc. as npm-installable plugins. Medusa Docs

It also makes integrations feel fairly natural:

External ERP
     ↓
  Medusa Module
     ↓
    Workflow
     ↓
Medusa Commerce Modules
     ↓
   Storefront

Medusa's documentation specifically describes using modules for third-party services and workflows to orchestrate operations across systems. Medusa Docs

And the underlying architecture is nicely separated into API → workflows → modules → database, which makes it easier to reason about where custom code belongs. Medusa Docs

The main alternative: Vendure

I'd seriously consider Vendure if you're a TypeScript-heavy developer.

Its plugin architecture is excellent, and its approach is arguably a little more conventional and predictable than Medusa. If your projects tend to be complex B2B/catalog/order-management systems rather than highly bespoke commerce applications, Vendure deserves a very close look.

When I'd choose Saleor instead

Saleor is particularly compelling if you want the platform to remain a relatively untouched commerce engine and put your custom logic outside it.

It's GraphQL-only and designed around API-based extensibility, with apps, webhooks, metadata, API extensions, and dashboard extensions. GitHub Saleor Documentation

That's excellent for a team that says:

"We don't want to modify the commerce backend; we want our integrations to be independent services."

But for a solo/freelance developer who frequently gets requests like "can you make checkout work differently for this client?", "add this custom entity and connect it to orders", or "change this business workflow", I think Medusa's in-process modules/workflows are more convenient.

One important distinction

I'd separate "easiest to extend" from "easiest to deploy for a client."

If your clients mostly want:

WordPress + store + 50 existing plugins + minimal custom development

then WooCommerce may actually make you more money because of its enormous ecosystem.

But if your typical client says:

"We have an ERP, custom fulfillment rules, a weird pricing system, an external CRM, and a bespoke storefront. Can you make all of this talk to each other?"

I'd start with Medusa.

My short version:

Medusa → best overall for your freelance/custom-integration niche.
Vendure → best alternative if you want a very structured TypeScript plugin architecture.
Saleor → best if you strongly prefer API/GraphQL and external-service architecture.
Sylius → best if you're already deep into PHP/Symfony.
WooCommerce → best when leveraging an existing ecosystem matters more than architectural elegance.

If you're building 5–20 client stores rather than one giant store, I'd also evaluate them specifically on how easily you can create your own reusable "starter commerce stack" and deploy/upgrade it across clients. That's where the differences become much more interesting.

If your main business is building custom stores and integrations for clients, I’d rank them:

1. Medusa — best overall for a freelance developer
2. WooCommerce — easiest if clients need a huge ecosystem
3. Sylius — excellent for complex PHP/Symfony projects
4. Saleor — powerful, but more architecture than you may need

Why I'd pick Medusa

Medusa is unusually well suited to the exact scenario you described: different clients needing bespoke integrations and business logic.

Its current architecture gives you first-class concepts for:

• Custom data models/modules
• API routes
• Workflows
• Workflow hooks
• Events/subscribers
• Scheduled jobs
• Links between your models and commerce models
• Reusable plugins

That means an ERP integration, custom pricing engine, marketplace functionality, fulfillment provider, subscription system, etc. can be implemented as actual application components rather than a pile of overrides. Medusa Docs Medusa Docs Medusa Docs

The particularly useful part for a freelancer is plugins: Medusa lets you package modules, workflows, API routes, admin extensions, subscribers, and other customizations into reusable packages that you can install across projects. Medusa Docs Medusa Docs

So you could gradually build your own internal toolkit:

your-medusa-toolkit/
├── erp-connector
├── custom-pricing
├── b2b-accounts
├── shipping-integrations
├── product-importers
└── client-specific modules

Then reuse pieces on the next client rather than starting from zero.

Where WooCommerce wins

If "easiest to extend" means "I want to make almost anything happen with the least amount of ecosystem friction," WooCommerce is still extremely compelling.

Its PHP/WordPress architecture is familiar to a huge number of developers, and WooCommerce exposes REST APIs plus numerous PHP extension APIs for things like payments, shipping, settings, and core behavior. The WooCommerce Developer Blog The WooCommerce Developer Blog

The tradeoff is architectural cleanliness. You can get extraordinarily far with hooks and plugins, but large custom projects can eventually become a web of WordPress/WooCommerce hooks, plugin interactions, and compatibility concerns.

I'd choose WooCommerce when the client wants:

• WordPress + ecommerce
• lots of existing plugins
• relatively conventional stores
• easy handoff to non-developer WordPress teams
• maximum availability of third-party integrations

I'd choose Medusa when the store is really becoming a custom commerce application.

Sylius is the sleeper choice

If you're a strong PHP/Symfony developer, Sylius deserves serious consideration. Its plugin architecture is explicitly designed around extending the platform without modifying core code, and it supports reusable plugins for things such as payment gateways, CRM/ERP integrations, wishlists, and custom business functionality. Sylius Academy

It's particularly attractive for clients with sophisticated B2B/business rules where you want a conventional, strongly structured backend rather than a WordPress-based system.

My practical recommendation

For your freelance business, I'd probably standardize on:

Medusa + Next.js + PostgreSQL

and keep WooCommerce in your toolbox for clients who specifically want WordPress.

The important distinction is:

WooCommerce is the easiest ecommerce platform to extend incrementally. Medusa is the easiest to turn into a custom commerce application.

For custom integrations, I'd favor Medusa. Its current framework explicitly treats third-party integrations as modules + workflows + events rather than something you have to bolt awkwardly onto the platform. Medusa Docs

If you tell me what kinds of integrations your clients typically need (ERP, Shopify migration, POS, shipping, subscriptions, B2B pricing, marketplaces, etc.), I can give you a freelancer-oriented Medusa vs WooCommerce vs Sylius comparison, including development speed, hosting, maintenance, and how reusable your code can be.

If your main business is building custom integrations for clients, I’d put Medusa at the top of the list right now.

My ranking for a freelance/custom-integration workflow

1. Medusa — best for maximum developer control
2. Shopware 6 — best for deep customization + mature merchant features
3. WooCommerce — easiest overall if clients want WordPress/ecosystem compatibility
4. Saleor — excellent API-first architecture, but more opinionated
5. Sylius — extremely flexible, particularly if you're comfortable with Symfony/PHP

Why I’d choose Medusa

Medusa is essentially a commerce framework rather than a giant monolithic store that you're expected to work around. Its architecture gives you modules, workflows, API routes, events, custom data models, integrations, and admin extensions as first-class customization points. Medusa Documentation Medusa Documentation

For example, a client wants:

Shopify-like store + custom ERP + unusual pricing engine + marketplace functionality + bespoke fulfillment

With Medusa, you can create custom modules and providers, link your data models to commerce entities, subscribe to events, and package reusable functionality into plugins. Medusa Documentation Medusa Documentation

That's particularly attractive for a freelancer because you can build your own integration toolkit and reuse it across clients.

It's also TypeScript/Node-based, which makes it particularly nice if your usual stack is React/Next.js/Node.

Where Shopware beats it

I'd choose Shopware 6 instead if your clients are traditional merchants who need a lot of ecommerce functionality out of the box.

Shopware has both an app system and deep PHP/Symfony plugins that can modify internal functionality and database schema. Its API-first architecture also makes ERP/PIM/WMS/CRM integrations straightforward. Shopware Developer Docs Shopware

The important distinction is:

• Medusa: "Let's build the commerce system around this client's requirements."
• Shopware: "Here's a very capable commerce system; let's customize it heavily."

For agency/freelance work, that distinction matters.

WooCommerce is the pragmatic option

Don't underestimate WooCommerce. Its extension ecosystem is enormous, and its APIs expose products, orders, customers, coupons, shipping, payments, etc. It also provides PHP APIs for deeply modifying core behavior. The WooCommerce Developer Blog

If your clients are already using WordPress, WooCommerce can be dramatically faster to deliver than introducing a new commerce stack.

My actual recommendation

If you're building custom stores repeatedly, I'd specialize around:

Medusa + Next.js + PostgreSQL + your own reusable integration modules

Then keep Shopware in your toolkit for larger/more conventional ecommerce clients.

I'd choose WooCommerce when the client's existing WordPress ecosystem makes it the obvious choice.

The key reason I'd favor Medusa for your particular business model is that you're selling development and integration expertise, not just deploying an ecommerce package. Its architecture is deliberately designed around customization and integrations. Medusa Documentation Medusa Documentation

If you tell me your usual stack (e.g. Laravel/PHP, Node/TypeScript, Python, or .NET) and the kinds of integrations you build (ERP, payment, shipping, marketplaces, subscriptions, etc.), I can narrow this down to the best 1–2 platforms for your agency workflow.

For a freelance developer building custom integrations for clients, I’d optimize less for “best ecommerce platform” and more for:

• How cleanly can I add business logic?
• Can I avoid forking core code?
• Are integrations first-class (webhooks, APIs, modules)?
• Can I hand it off to another developer later?

My shortlist:

OpenReplay Blog Toolradar## My recommendation for a freelance integration business

1. Choose Medusa if you mostly build custom experiences

This is probably what I’d pick today for a developer starting a commerce integration practice.

Why:

• TypeScript end-to-end
• Clean module architecture
• Good for ERP/CRM/PIM/shipping/payment integrations
• Headless by design
• Easy to pair with Next.js, React Native, mobile apps, kiosks, etc.

The tradeoff: you are building more yourself. It has fewer ready-made merchant plugins than WooCommerce. WPBundle

Typical client projects:

• “Connect our store to SAP/NetSuite”
• “Custom pricing engine”
• “Wholesale portal”
• “Marketplace”
• “Subscription + custom fulfillment logic”
• “One backend powering web + mobile + POS”

2. Choose WooCommerce if your clients are small businesses

WooCommerce wins when the requirement is:

“We need a store in 4 weeks with payments, shipping, email marketing, accounting, and 20 existing plugins.”

Its ecosystem is enormous, so you often solve problems by configuring or extending rather than building from scratch. Toolradar WPBundle

The downside:

• WordPress plugin conflicts
• More legacy patterns
• Complex custom workflows can become messy

3. Choose Vendure if you want a TypeScript framework with strong customization

Vendure is interesting for freelancers who want something closer to “write the commerce system you need” while staying in Node/TypeScript. Its plugin system is designed around extending behavior rather than patching the core. OpenReplay Blog

Platforms I’d be cautious about as a solo freelancer

Magento

Great technology, but projects can become maintenance-heavy:

• complicated deployments
• upgrades are significant
• clients often underestimate costs

Good if you target enterprise retainers.

Saleor

Architecturally strong, especially if you like GraphQL and service-oriented systems, but it can require more engineering discipline and infrastructure than many freelance clients expect. OpenReplay Blog

A practical freelance stack

If I were building a reusable agency/freelance toolkit:

• Default: Medusa + Next.js + PostgreSQL
• Budget/SMB: WooCommerce + custom plugins
• Complex B2B: Vendure or Sylius
• Enterprise: Magento or Saleor

The biggest business advantage is not the platform itself — it’s picking one stack you can build integrations for repeatedly. A freelancer who knows one commerce engine deeply usually beats someone who has touched ten platforms.

A practical freelance stack

If I were building a reusable agency/freelance toolkit:

If your priority is “I want to build custom integrations quickly and reuse my work across clients,” I’d pick Medusa.

My ranking for a freelance developer

1. Medusa — best overall

• TypeScript/Node.js, so the extension model feels natural if you're a JS/TS developer.
• Custom business logic can live directly in modules, workflows, API routes, subscribers, and plugins rather than forcing you to bolt on a separate application. Medusa Docs Medusa Docs Medusa Docs
• Third-party integrations are a first-class concept: payment, fulfillment, ERP, CMS, event systems, storage, etc. can be implemented as modules/providers. Medusa Docs Medusa Docs
• You can package your reusable client-specific functionality as plugins and install it across projects. Medusa Docs
• REST APIs and a headless architecture make it particularly nice for custom React/Next.js storefronts. Medusa Docs
• Saleor — best if you're GraphQL/Python-oriented

• Excellent API-first architecture and strong support for apps/integrations.
• GraphQL is very clean for custom storefronts.
• Particularly attractive for sophisticated multi-channel/B2B setups.
• The tradeoff is that its Python/Django ecosystem may be less convenient if your normal stack is TypeScript. Its documentation explicitly centers apps, API extensions, dashboard extensions, and custom modeling. Saleor Documentation
• WooCommerce — easiest for conventional client sites

• Massive plugin ecosystem and enormous pool of WordPress developers.
• Very easy to hand off to a client who already knows WordPress.
• But for deeply custom integrations, I find its WordPress/plugin/hook architecture less pleasant than a purpose-built headless framework.
• I'd choose it when the client's requirements are mostly conventional ecommerce + existing WordPress plugins, rather than when you're building a custom commerce system.
• Sylius — excellent, but more specialized

• Very powerful if you like PHP/Symfony and want a true ecommerce framework rather than a turnkey store.
• I'd consider it seriously for large, unusual commerce implementations, but not necessarily as your default freelance stack unless you're already strong in Symfony.

Why I'd choose Medusa for your particular business

The important distinction is extensibility vs. configurability.

If you're repeatedly getting clients asking for things like:

“When an order comes from ERP X, transform it, send it to warehouse Y, calculate this weird shipping rule, sync inventory with Z, and expose a custom endpoint for our mobile app.”

Medusa's architecture maps nicely onto that problem:

API route → workflow → modules → external integration

You can create a custom module for the external system, a workflow for the business process, subscribers for events, and potentially turn the whole thing into a reusable plugin. Medusa Docs Medusa Docs

That's much closer to building software on top of a commerce engine than merely customizing a store.

The other big advantage for freelancing is reuse. You could gradually build your own internal library of things like:

• ERP connectors
• custom payment providers
• shipping integrations
• product importers
• inventory synchronizers
• CRM integrations
• custom pricing logic
• B2B functionality
• client-specific admin extensions

…and package the recurring pieces as Medusa modules/plugins. Medusa Docs Medusa Docs

One caveat

Medusa is not the lowest-ops option. Self-hosting means you're responsible for the Node server, PostgreSQL, Redis and associated infrastructure/configuration. Medusa's own documentation explicitly calls out that self-hosting requires configuring and maintaining those pieces. Medusa Docs Medusa Docs

So my rule of thumb would be:

Custom integrations + modern JS stack → Medusa

GraphQL + Python + sophisticated commerce → Saleor

WordPress clients + lots of existing plugins → WooCommerce

Symfony/PHP + very bespoke enterprise commerce → Sylius

For a freelance developer trying to standardize on one platform for many custom client builds, I'd start with Medusa. Its modular architecture is unusually well aligned with turning your integration work into reusable IP.

For a freelance developer building multiple client stores with custom integrations, I’d pick Medusa first.

The short version:

Why I'd choose Medusa

Medusa is unusually well suited to the "every client needs something weird" situation.

Its architecture explicitly treats customization as a first-class concern: you can create modules, data models, API routes, workflows, event subscribers, scheduled jobs, and plugins inside the application. Medusa Docs Medusa Docs

For example, imagine a client needs:

Shopify-like store + ERP sync + custom pricing rules + third-party fulfillment + special B2B checkout.

With Medusa, you can structure that roughly as:

src/
├── modules/
│   ├── erp/
│   ├── fulfillment/
│   └── customer-pricing/
├── workflows/
│   ├── sync-order.ts
│   ├── calculate-custom-price.ts
│   └── fulfill-order.ts
├── api/
│   └── ...
└── subscribers/
    └── order-placed.ts

The important part is that these aren't merely external services bolted onto an ecommerce API. Medusa lets your custom modules participate directly in the application's workflows and dependency container. Medusa Docs Medusa Docs

That's particularly attractive for a freelancer because you can turn successful client-specific integrations into reusable plugins and install them in subsequent projects. Medusa plugins can bundle modules, API routes, workflows, hooks, subscribers, scheduled jobs, and admin extensions. Medusa Docs

Sylius is the strongest alternative

If you're a PHP/Symfony developer, I'd seriously consider Sylius instead.

Its plugin architecture is excellent: plugins are Symfony bundles that extend Sylius without modifying core, and they're explicitly designed for things like payment gateways, CRM/ERP integrations, CMSs, wishlists, etc. Sylius Academy

In fact, I'd choose Sylius over Medusa if:

• Your clients are predominantly PHP shops.
• You already know Symfony deeply.
• You're building highly customized back-office/business workflows.
• You want the mature Symfony ecosystem underneath the commerce layer.

Saleor is excellent, but I'd put it third

Saleor is compelling if you love GraphQL and want integrations to live as separate applications.

Saleor's model is basically:

Saleor
   │
   ├── GraphQL API
   │
   ├── Webhooks
   │
   └── Apps
        ├── ERP
        ├── PIM
        ├── loyalty
        └── custom business logic

Its documentation specifically supports building apps and dashboard extensions, and its app architecture lets you add custom logic without modifying the core. Saleor Documentation GitHub

That's powerful, but I think Medusa's "custom code lives inside the commerce application" model is more convenient for a solo developer when you're frequently doing unusual integrations.

And WooCommerce?

WooCommerce is the pragmatic choice if your clients want traditional WordPress.

Its enormous plugin ecosystem is a major advantage, but that's different from being pleasant to extend. For a developer who routinely needs to invent custom commerce behavior rather than assemble existing plugins, I'd rather have Medusa's framework-style architecture.

My recommendation

I'd narrow it down like this:

TypeScript/Node → Medusa
PHP/Symfony → Sylius
Python/GraphQL → Saleor
WordPress/client wants lots of existing plugins → WooCommerce

For your particular business model, Medusa is probably the best default. Its module + workflow + plugin architecture maps very nicely onto a freelance agency model where you build an integration once, refine it, then reuse it across clients. Medusa Docs Medusa Docs

If you tell me what kinds of integrations your clients typically need (ERP, Stripe/custom payments, shipping, marketplaces, subscriptions, PIM, B2B pricing, etc.), I can also rank Medusa vs Sylius vs Saleor specifically for that workload.

If your main criterion is “I want to build custom integrations for lots of different clients without fighting the platform,” I’d pick Medusa.

My ranking for a freelance developer

1. Medusa — best overall for custom integrations
2. Vendure — arguably the nicest alternative if you want a very structured TypeScript plugin architecture
3. Sylius — excellent if you’re comfortable with Symfony/PHP
4. Saleor — powerful, especially for B2B, but more infrastructure/architecture than you usually need
5. WooCommerce — easiest to find an existing integration for, but less pleasant when you need deep custom business logic

Why Medusa is my default

Medusa is TypeScript/Node-based and was designed around modular commerce rather than being a monolithic CMS with ecommerce bolted on. Its modules cover things like products, carts, orders, pricing and fulfillment, and you can replace or extend pieces with your own code. OSSAlt OSSAlt

For freelance work, that's particularly attractive because your typical project becomes:

Next.js storefront → Medusa → custom modules/integrations → client's ERP/CRM/WMS/payment/shipping system

You can keep the whole custom stack in JavaScript/TypeScript, which reduces context switching and makes it easier to reuse patterns between clients. OpenReplay Blog Designodin

The downside is important: Medusa's extension ecosystem is much smaller than WooCommerce's. If a client wants some obscure accounting/shipping/marketing integration, you're more likely to build it yourself. WPBundle

When I'd choose something else

Choose Vendure if you want Node/TypeScript but put a premium on a formal plugin architecture and type-safe extension points. It's a particularly compelling choice for a developer building a reusable integration layer across many projects. OpenReplay Blog

Choose Sylius if you're already strong in Symfony. It's less “plug-and-play ecommerce” and more like an ecommerce framework you can shape around the client's business. That's fantastic for highly bespoke projects, but the Symfony learning curve makes it a worse universal recommendation for a JS-focused freelancer. OpenReplay Blog Edana

Choose Saleor when the clients tend toward sophisticated B2B/multichannel requirements. Its GraphQL-first architecture and built-in multi-channel, multi-warehouse capabilities are excellent, but you're taking on Python/Django plus Redis/Celery infrastructure rather than a relatively straightforward Node stack. OpenReplay Blog Ribbsaeter Systems

Choose WooCommerce when “does an integration/plugin already exist?” matters more than architectural elegance. Its enormous plugin ecosystem is a huge advantage, particularly for conventional SMB stores. But deeply customized workflows can eventually turn into a pile of WordPress hooks, plugins, and compatibility issues. OSSAlt ossium

For your specific business model

I'd actually standardize your freelance offering around Medusa + Next.js + PostgreSQL, and build your own small library of reusable integration modules:

• ERP sync
• CRM/customer sync
• payment providers
• shipping/fulfillment
• tax
• inventory
• webhooks/event processing
• product/catalog imports
• custom checkout logic

Then each new client mostly becomes configuration + a handful of client-specific adapters, rather than starting from scratch.

If you tell me what kinds of clients/integrations you typically build (Shopify migrations, ERP integration, subscriptions, marketplaces, B2B, custom checkout, etc.), I can narrow this down to Medusa vs Vendure vs Sylius and tell you which I'd standardize on.

When I'd choose something else

Choose Vendure if you want Node/TypeScript but put a premium on a formal plugin architecture and type-safe extension points. It's a particularly compelling choice for a developer building a reusable integration layer across many projects. OpenReplay Blog

Choose Sylius if you're already strong in Symfony. It's less “plug-and-play ecommerce” and more like an ecommerce framework you can shape around the client's business. That's fantastic for highly bespoke projects, but the Symfony learning curve makes it a worse universal recommendation for a JS-focused freelancer. OpenReplay Blog edana.ch

Choose Saleor when the clients tend toward sophisticated B2B/multichannel requirements. Its GraphQL-first architecture and built-in multi-channel, multi-warehouse capabilities are excellent, but you're taking on Python/Django plus Redis/Celery infrastructure rather than a relatively straightforward Node stack. OpenReplay Blog ribbsaetersystems.com

Choose WooCommerce when “does an integration/plugin already exist?” matters more than architectural elegance. Its enormous plugin ecosystem is a huge advantage, particularly for conventional SMB stores. But deeply customized workflows can eventually turn into a pile of WordPress hooks, plugins, and compatibility issues.

For your specific business model

If your main business is building custom stores for clients, I’d put Medusa at the top of the list right now—especially if you’re comfortable with TypeScript/Node.

My ranking for a freelance developer

1. Medusa — best overall for custom integrations
2. Vendure — excellent if you prefer NestJS/GraphQL
3. Sylius — excellent if you’re a PHP/Symfony developer
4. Saleor — powerful, particularly for Python/GraphQL and larger B2B builds
5. WooCommerce — easiest to get a conventional store running, but less pleasant for deeply custom commerce logic

Why I’d choose Medusa

Medusa is deliberately structured around modules, workflows, API routes, events, and plugins, rather than expecting you to hack the core. Its current architecture lets you create custom modules, connect their data to built-in commerce models, hook custom behavior into existing workflows, and package reusable integrations as plugins. Medusa Docs Medusa Docs Medusa Docs

That maps extremely well to freelance work. For example, you could build a reusable:

• ERP integration
• custom pricing engine
• B2B customer/account system
• shipping provider integration
• marketplace functionality
• subscription system
• PIM connector
• client-specific fulfillment workflow

…and turn the common pieces into your own reusable modules/plugins.

Medusa even explicitly supports linking your custom data models to core models such as Products and Customers without modifying those core models directly. Medusa Docs Medusa Docs Medusa Docs

Where the others fit

Vendure is probably my second choice. It's also TypeScript/NestJS-based and has a strong plugin architecture. I'd choose it over Medusa if you're already heavily invested in NestJS and want a more conventional enterprise backend architecture.

Sylius is arguably the best choice if you're a Symfony/PHP developer. Its plugin system is mature and specifically designed for extending commerce without modifying core code. Sylius Academy

Saleor is attractive when the client needs sophisticated multi-channel/B2B commerce and your team likes Python/Django + GraphQL. It's less compelling for a solo JS/TS freelancer simply because the ecosystem and architecture are optimized somewhat differently.

WooCommerce wins if the client wants a traditional WordPress site with a huge plugin ecosystem. But for the sort of "client has an unusual business process and I need to make the commerce engine behave differently" work you're describing, I'd rather start with Medusa/Vendure/Sylius.

The important distinction

I'd separate "easiest to extend" from "easiest to build a store with."

For your business, the former matters much more.

So if you're starting a new freelance commerce stack today, my default would be:

Next.js storefront + Medusa backend + PostgreSQL + your own reusable Medusa modules/plugins.

That gives you a pretty compelling agency/freelancer model: instead of rebuilding integrations for every client, you gradually accumulate your own commerce framework on top of Medusa. Medusa's documentation explicitly supports packaging reusable customizations as plugins that can be installed across projects. Medusa Docs

If you tell me your preferred language (PHP/TS/Python), typical client size, and the kinds of integrations you build, I can narrow this down to Medusa vs Vendure vs Sylius and explain which one will make you the most money/least maintenance as a freelancer.

For a freelance developer building custom integrations for clients, I’d optimize for extension architecture, maintainability, and speed of custom development, not just “number of plugins.” The best choice depends heavily on your stack:

blog.openreplay.com

My ranking for a freelance integration developer

1. Medusa (best overall for greenfield custom stores)
If you’re building things like:

• ERP integrations
• custom pricing engines
• unusual checkout flows
• subscription logic
• marketplace features
• custom fulfillment

Medusa is a strong fit because it is designed as a commerce engine rather than a monolithic storefront. Its TypeScript stack also makes it easy to share types and patterns with modern frontend apps. opensourceprojects.cc

2. Vendure (best developer experience if you like TypeScript)
Vendure is arguably the cleanest architecture for someone who expects to write lots of custom modules. It uses a plugin model with GraphQL extensions and typed server-side code. The downside is a smaller ecosystem, so you build more yourself. blog.openreplay.com

3. WooCommerce (best money-maker for agency work)
If your clients are:

• local businesses
• brands with existing WordPress sites
• stores needing lots of marketing plugins

WooCommerce can be unbeatable because the ecosystem solves many problems already. The tradeoff is that deep customization often means wrestling with WordPress conventions and plugin conflicts. selfhosting.sh

Platforms I’d be cautious about for freelance work

Magento/Open Source

• Very capable.
• Lots of enterprise demand.
• But onboarding clients into a maintainable custom codebase can become a project by itself.

PrestaShop/OpenCart

• Good traditional store platforms.
• Less attractive if your main value proposition is “I build custom integrations and workflows.”

A practical freelance stack choice

If I were building a reusable consulting skillset:

• Default: Medusa + Next.js + PostgreSQL
• Alternative: Vendure + Next.js for highly customized clients
• Quick revenue projects: WooCommerce
• Enterprise contracts: Shopware or Magento

The biggest advantage of Medusa/Vendure is that you’re selling engineering work rather than becoming a plugin installer. You can build reusable integration modules (payments, ERPs, shipping providers, inventory systems) and carry that expertise between clients. codenote.net

If you tell me your preferred stack (Laravel/PHP, Node/TS, Python, Ruby) and the typical client size (small businesses vs $1M+ merchants), I’d narrow it down further.

For a freelance developer building custom client stores, I'd shortlist Vendure and Medusa. If your main criterion is “I need to integrate weird third-party systems without fighting the platform,” I'd currently give Vendure a slight edge.

My ranking for extensibility

🥇 Vendure — my pick for your use case

Vendure's plugin architecture is exceptionally well suited to agency/freelance work. A plugin can add database entities, services, REST endpoints, GraphQL queries/mutations, custom fields, event handlers, background jobs, and integrations with external systems. It's built on NestJS, so if you're comfortable with TypeScript, the mental model is very natural. docs.vendure.io

For example, a client says:

"When an order is placed, send it to our ERP, reserve inventory in another system, add a custom approval step, and expose the resulting status in the storefront."

That's basically what Vendure's plugin model is designed for.

You can keep the integration isolated:

plugins/
  erp/
  shipping/
  loyalty/
  marketplace/
  custom-pricing/

That is particularly attractive when you're building multiple stores for different clients because you can turn your integrations into reusable packages.

Vendure also has a plugin directory, so you aren't necessarily implementing every common integration yourself. docs.vendure.io

🥈 Medusa — arguably better for maximum architectural freedom

I'd choose Medusa if you want the commerce backend to behave more like a composable application framework.

Its architecture separates API routes → workflows → modules → data, and custom modules can integrate external services. Workflows are specifically designed to orchestrate operations across systems, including things such as ERP synchronization. docs.medusajs.com

That's excellent for projects like:

Storefront
   ↓
Medusa
   ├── Shopify-like commerce logic
   ├── ERP module
   ├── PIM module
   ├── CRM module
   ├── custom pricing
   └── fulfillment integration

The big advantage is that integrations become modules, rather than a pile of platform-specific hooks.

Medusa's own documentation describes it as a commerce framework intended to be customized around the business rather than merely configured. docs.medusajs.com

When I'd pick each

Choose Vendure if:

• You're primarily a TypeScript developer.
• You like NestJS/DI/modules.
• You want a very straightforward plugin architecture.
• Clients frequently need custom admin functionality.
• You want reusable integrations across projects.
• You want GraphQL but don't want to build everything yourself.

Choose Medusa if:

• You want maximum architectural control.
• Integrations/workflows are the heart of the project.
• You prefer a modular backend architecture.
• You're building unusual commerce experiences rather than conventional stores.
• You want to treat commerce as infrastructure inside a larger application.

Choose Sylius if:

• You're a strong PHP/Symfony developer.
• The client has complicated domain/business rules.
• You don't mind a more traditional framework-style development experience.

Choose Saleor if:

• GraphQL is central to your architecture.
• You're comfortable with Python/Django.
• The client needs sophisticated multi-channel/multi-warehouse commerce.

The important distinction

For a freelancer, I'd optimize less for “which has the most features?” and more for:

“Can I turn a client's bizarre requirement into an isolated module/plugin without modifying the core?”

That's where Vendure and Medusa stand out.

If I were starting an agency today and wanted one default platform for custom integration-heavy stores, I'd probably standardize on Vendure. If I wanted to build more application-like, highly bespoke commerce systems, I'd lean Medusa.

And I would not default to WooCommerce/Magento just because their ecosystems are larger—their ecosystems are fantastic, but custom integrations can increasingly become plugin/theme/core-hook archaeology rather than clean application development.

If you tell me your typical client stack (Next.js/React, PHP, Python, etc.) and the kinds of integrations you usually build (ERP, PIM, shipping, subscriptions, marketplaces, custom pricing), I can narrow this down to one.

If your main business is building custom integrations for clients, I’d shortlist Sylius, Shopware, and Medusa—and my default pick would be Sylius if you’re comfortable with PHP/Symfony.

My ranking for a freelance integration shop

🥇 Sylius — probably the best for your use case

Sylius is less of a "finished store builder" and more of an ecommerce framework built on Symfony. That distinction is valuable when you're repeatedly doing unusual integrations.

Its architecture is deliberately modular: you can replace individual pieces and connect external PIMs, CRMs, marketing systems, etc., rather than fighting a monolithic platform. It also exposes an API-first architecture through API Platform. plugins.sylius.com

The plugin ecosystem is also reasonably mature, with dedicated integrations for payments, shipping, ERP/CRM systems, search, marketing, and other services. addons.sylius.com

Why I'd choose it for a freelance business: you can treat each client integration as a proper Symfony module rather than accumulating hacks around an existing CMS.

🥈 Shopware — best if clients are more enterprise-oriented

Shopware is probably the strongest alternative.

Shopware has both Apps and Plugins. For self-hosted stores, plugins can deeply modify the application, while apps can keep logic outside the store and communicate through APIs/webhooks. developer.shopware.com

That gives you a particularly useful spectrum:

external integration → App → Plugin → deep platform customization

Shopware explicitly positions its APIs for ERP, PIM, CRM, custom frontends and other integrations. plugins.sylius.comwww.shopware.comossalt.com

I'd favor it over Sylius if your target clients are established retailers with complicated catalogs, ERP/PIM requirements, B2B workflows, multiple sales channels, etc.

🥉 Medusa — best if you're a TypeScript/Node developer

Medusa is attractive if you want to stay entirely in the JavaScript/TypeScript ecosystem. It's headless-first rather than a traditional PHP ecommerce application, which makes it particularly pleasant for custom React/Next.js storefronts and external services. Recent comparisons also put it among the leading developer-oriented open-source commerce backends. www.wpbundle.com

I'd pick Medusa over Sylius if your existing expertise is strongly TypeScript/Node and you're building mostly headless stores.

Where WooCommerce fits

WooCommerce is actually a very pragmatic freelance choice. Its enormous plugin ecosystem means you can solve a lot of ordinary requirements without writing them yourself. ossalt.com

But for unusual integrations and business logic, I prefer Sylius/Medusa. WooCommerce's WordPress/plugin architecture can become difficult to reason about when a project accumulates many third-party plugins and custom hooks.

What I'd do in your position

If you're trying to establish a repeatable freelance stack, I'd probably choose:

PHP/Symfony → Sylius
TypeScript/Node → Medusa
Enterprise/European merchants → Shopware

And I'd avoid Magento/Adobe Commerce unless your niche specifically demands it. It's extremely powerful, but "easy to extend" isn't the same thing as "powerful enough to extend."

The important distinction is that Sylius and Medusa let you make the commerce engine part of your application, whereas platforms like WooCommerce and Shopware start with a more complete merchant application and give you extension mechanisms around it.

If you tell me your preferred stack (PHP/TS/Python), typical client size, and whether you build headless storefronts, I can narrow this down to one platform and explain exactly how I'd structure your reusable integration architecture.

For a freelance developer building multiple client stores with bespoke integrations, I'd pick Medusa as the default.

My ranking

Why Medusa is particularly attractive for you

Medusa is essentially designed around the problem you're describing: take a commerce backend and adapt it to each client's business rather than forcing the business into the platform's model.

Its current architecture gives you:

• Custom modules for new domains/integrations, with their own data models and services.
• Workflows for complicated multi-step business operations, including rollback behavior.
• Custom API routes without having to build a separate integration service.
• Events/subscribers for synchronization and automation.
• Module replacement, so you can substitute parts of the commerce stack with your own implementation or a third-party service.
• Admin customization for client-specific back-office functionality.

Those aren't just theoretical extension points—the current documentation explicitly positions modules, workflows, API routes, data models, events, and admin customization as the normal way to customize a Medusa application. Medusa Docs Medusa Docs Medusa Docs

The architecture is especially nice for integrations. For example, you could have:

Medusa → custom ERP module → ERP

Medusa → custom fulfillment module → 3PL

Medusa → event subscriber → CRM

without turning the whole project into a pile of external middleware. Medusa's modules can encapsulate third-party integrations, and its workflows can orchestrate operations across them. Medusa Docs Medusa Docs

The big alternative: Sylius

If you're a PHP/Symfony developer, I'd seriously consider Sylius instead.

Sylius is arguably even more "framework-like" than Medusa. Its plugin architecture is excellent for turning client-specific functionality into reusable packages, and its ecosystem explicitly supports custom/internal plugins as well as community and commercial ones. Sylius Academy Sylius Addons Marketplace

So my rule of thumb would be:

TypeScript/Node → Medusa
PHP/Symfony → Sylius

Where WooCommerce fits

WooCommerce is the opposite tradeoff: its architecture isn't as elegant for deeply customized commerce systems, but its enormous plugin ecosystem can make ordinary client requirements dramatically faster.

If a client says:

"We need WordPress, Stripe, subscriptions, Mailchimp, a normal catalog, and a weird shipping plugin."

I'd probably choose WooCommerce.

If they say:

"We manufacture configurable products, have an ERP with unusual inventory semantics, need custom pricing rules, and orders have to flow through three external systems."

I'd much rather start with Medusa or Sylius.

What I'd build as a freelancer

I'd actually create a reusable Medusa starter rather than treating every client as a blank project:

your-commerce-starter/
├── modules/
│   ├── erp/
│   ├── shipping/
│   ├── customer-data/
│   └── ...
├── workflows/
│   ├── sync-order/
│   ├── sync-inventory/
│   └── ...
├── subscribers/
├── api/
├── admin/
└── storefront/

Then each client gets the starter plus their particular integrations. Medusa explicitly supports reusable modules/customizations, which makes this approach particularly attractive for an agency/freelancer workflow. Medusa Docs

Bottom line: if your differentiator is "I can connect your store to whatever weird systems your business uses," I'd choose Medusa first, Sylius second, and WooCommerce when its ecosystem saves you more work than its architecture costs you.

If you tell me your preferred stack (Node/TS, PHP, Python) and the kinds of integrations your clients usually need (ERP, POS, marketplaces, subscriptions, B2B pricing, etc.), I can narrow this down to a much more opinionated choice.

If your priority is “I need to build custom integrations for many different clients without fighting the platform,” my first choice today would be Medusa, with Vendure as a very close second.

My ranking for a freelance developer

1. 🥇 Medusa — probably what I'd pick for your business

Medusa documentation

Medusa is particularly attractive when your value as the developer is integrating the store with other systems.

Its architecture explicitly supports custom API routes, workflows, data models, modules, event subscriptions, admin customization, and integrations. docs.medusajs.comdocs.medusajs.com

For example, a client might need:

Shopify-like storefront + ERP + custom pricing engine + warehouse API + CRM + unusual checkout logic

Instead of building a separate integration service around the ecommerce platform, you can put much of that logic directly into Medusa's architecture. Its modules can also integrate external systems such as ERPs, fulfillment providers, CMSs, etc. docs.medusajs.comdocs.medusajs.com

It's also TypeScript/Node, which is a major advantage if you're already doing modern web development.

Why I like it for freelancing:

• TypeScript end-to-end
• Modular architecture
• Custom business logic is a first-class concept
• REST/API-oriented
• PostgreSQL
• Events and workflows
• Easy to build reusable integration modules
• Headless by design
• Self-hostable

The biggest downside is that you're choosing a relatively developer-centric commerce engine rather than an enormous traditional ecommerce ecosystem.

2. 🥈 Vendure — arguably even better if you love TypeScript + GraphQL

Vendure documentation

Vendure's plugin system is exceptionally good. Plugins can add database entities, modify configuration, extend GraphQL, communicate with external systems, react to events, and run background tasks. docs.vendure.io

That's almost exactly the feature set you'd want for client integrations.

For example, you could make:

client-project/
  plugins/
    erp-integration/
    custom-pricing/
    shipping-provider/
    loyalty/
    marketplace-sync/

And each piece can remain relatively isolated.

Vendure also lets you extend both its Shop API and Admin API with custom GraphQL queries/mutations. docs.vendure.io

I'd choose Vendure over Medusa when:

• You strongly prefer GraphQL
• You like NestJS/TypeScript architecture
• You expect complicated commerce rules
• You're doing B2B
• You want a very explicit plugin architecture

3. Shopware — excellent for bigger clients

Shopware developer documentation

Shopware is worth considering if your freelance clients are larger businesses, particularly in Europe.

Its self-hosted edition supports PHP plugins that can modify the database schema and use Symfony's extension mechanisms, alongside its app/API ecosystem. developer.shopware.com

It's more of a full-fledged established ecommerce platform than Medusa/Vendure.

That's both its strength and weakness:

Pros: mature commerce functionality, huge feature set, established ecosystem.

Cons: considerably more platform to learn and maintain.

For a freelancer doing lots of small-to-medium bespoke stores, I'd generally prefer Medusa/Vendure.

The interesting choice: Medusa vs Vendure

For your specific business, I'd narrow it down to these two.

Pick Medusa if:

“Every client has weird requirements, and I want the commerce engine to get out of my way.”

Pick Vendure if:

“I want a strongly structured ecommerce framework where custom functionality is packaged as clean TypeScript plugins.”

I'd personally lean Medusa for a freelance integration shop because its current framework is explicitly designed around customizations and integrations, including workflows and custom modules. docs.medusajs.comdocs.medusajs.com

One important distinction

If by "easiest to extend" you mean “I want to modify absolutely anything with the least resistance,” then WooCommerce deserves consideration. Its enormous WordPress/plugin ecosystem makes conventional customization incredibly accessible.

But if you mean:

“I want a clean technical foundation that I can repeatedly use to build bespoke commerce systems for clients.”

I'd choose Medusa → Vendure → Shopware, in that order.

If you tell me the kinds of integrations you typically build (ERP, shipping, POS, subscriptions, marketplaces, custom pricing, etc.), I can also compare Medusa vs Vendure specifically from a freelancer's perspective, including how I'd structure reusable plugins/modules across clients.

If custom integrations and developer extensibility are the priority, my first choice in 2026 is Medusa.

My ranking for a freelance developer

Why Medusa stands out: its architecture is explicitly designed around customization. You can create your own data models/modules, API routes, workflows, event subscribers, scheduled jobs, and admin extensions inside the application. Its modules can also encapsulate third-party integrations such as ERP, payment, fulfillment, CMS, etc. docs.medusajs.comdocs.medusajs.com

That maps extremely well to freelance work. For example, a client says:

"We need Shopify-like commerce, but orders have to sync to our ERP, pricing comes from our internal API, and checkout needs a custom approval workflow."

With Medusa, you can implement those as first-class modules/workflows rather than fighting a monolithic plugin system. You can also package your reusable customizations as plugins and reuse them across client projects. docs.medusajs.comdocs.medusajs.com

Medusa documentation

When I'd pick something else

Saleor would be my #2. It's exceptionally extensible through GraphQL, apps, webhooks, metadata, and API extensions. It's particularly attractive if you're already a Python/GraphQL shop or your clients need sophisticated multi-channel commerce. docs.saleor.io

Saleor documentation

Sylius is arguably better than Medusa if you're a strong PHP/Symfony developer and expect clients to need extremely deep customization of the commerce domain. Its flexibility comes with more framework-level complexity, though.

WooCommerce is the pragmatic choice when the client already lives in WordPress or needs access to an enormous existing ecosystem. But for new, integration-heavy, headless builds, I'd generally prefer Medusa's architecture over extending WordPress/WooCommerce.

For your specific business model

I'd lean toward Medusa + Next.js + PostgreSQL and build yourself a small reusable integration toolkit:

• ERP connector
• CRM/customer sync
• payment provider abstraction
• shipping/fulfillment connectors
• product/catalog importer
• webhook/event infrastructure
• client-specific modules
• reusable admin extensions

Medusa's module system is particularly useful here because custom modules can be reused across projects, and plugins can bundle modules, workflows, routes, subscribers, jobs, and admin extensions. docs.medusajs.comdocs.medusajs.com

So if your question is "Which platform will let me bend the ecommerce backend to whatever weird integration my next client asks for?" — Medusa is probably the easiest starting point.

If you tell me whether you prefer TypeScript, PHP, or Python, I can narrow it down to the best 2–3 choices for your stack and explain the tradeoffs.

If custom integrations and developer extensibility are your main criterion, I’d put Medusa at the top of the list.

My ranking for a freelance developer

🥇 Medusa — probably your best choice

Medusa is unusually well suited to the kind of work you're describing. Its framework lets you create custom data models, modules, API routes, workflows, event subscribers, scheduled jobs, and integrations inside the application, rather than having to bolt a separate service onto an otherwise rigid ecommerce platform. docs.medusajs.com

The particularly valuable feature for a freelancer is plugins. You can package a client-specific integration or reusable functionality as a plugin and install it across multiple Medusa projects. Plugins can contain modules, API routes, workflows, hooks, subscribers, jobs, links, and admin extensions. docs.medusajs.com

For example, you could eventually build your own reusable:

• ERP connector
• PIM connector
• custom B2B pricing system
• fulfillment integration
• subscription logic
• marketplace integration
• client-specific checkout functionality

…and reuse the underlying pieces across clients.

Medusa also explicitly supports using integrations as a middleware layer between commerce and external systems, including ERP, CMS, analytics, auth, storage, etc. docs.medusajs.com

Medusa Framework documentation

🥈 Saleor — excellent if you want everything API-first

Saleor is arguably the better choice if you want a strictly headless, API-centric architecture.

Saleor keeps its core relatively untouched and expects you to extend it through apps. Those apps communicate with Saleor through GraphQL and webhooks, and can have their own UI embedded into the dashboard. saleor.io

That's attractive for client work because you don't have to maintain a fork of the ecommerce core. Saleor also advertises 140+ webhook events and independently hosted apps/integrations. saleor.io

The tradeoff is architectural: Medusa feels more like a commerce framework you customize; Saleor feels more like a commerce engine you integrate with.

Saleor documentation

🥉 Sylius — fantastic if you're a Symfony/PHP developer

If you're already deeply comfortable with Symfony, I'd seriously consider Sylius. Its architecture is extremely customizable and is particularly good when the client's business rules are unusual.

But if you're starting from scratch and your goal is to build integrations quickly across many clients, I'd favor Medusa's TypeScript ecosystem.

What I'd choose for your business

If I were building a freelance ecommerce practice around custom integrations, I'd probably standardize on:

Medusa + Next.js + PostgreSQL + your own reusable integration plugins

That gives you a nice progression:

Client 1 → build integration
Client 2 → reuse 60–80% of it
Client 3 → turn it into a generic plugin
Client 10 → you've effectively built your own ecommerce integration toolkit

That's where Medusa is particularly compelling: its customization model is explicitly designed around reusable modules and plugins rather than repeatedly hacking the core. docs.medusajs.comdocs.medusajs.com

If you tell me what kinds of integrations your clients typically need (ERP, PIM, shipping, marketplaces, custom pricing, subscriptions, etc.), I can also compare Medusa vs Saleor vs Sylius specifically for that workload.

For your use case—freelance work where every client may need weird/custom integrations—I’d pick Medusa first, with Sylius as the main alternative.

My ranking for extensibility

Why I'd choose Medusa

Medusa is unusually well suited to the "client wants their ERP/CRM/warehouse/pricing system connected in some bizarre way" scenario.

Its architecture explicitly separates API routes → workflows → modules → database, and custom modules are first-class parts of the application. You can create your own data models and services and have them participate in the rest of the commerce system. docs.medusajs.comaddons.sylius.comdocs.saleor.io

More importantly for freelance work, integrations are treated as replaceable modules. Medusa documents custom providers for things like payments, fulfillment, notifications, storage, search, tax, authentication, and more. docs.medusajs.com

That means a client request like:

"When an order is placed, send it to our ERP, reserve inventory, create a shipping job, and update our CRM."

can be modeled as a proper workflow/integration rather than bolting a bunch of webhooks onto a monolithic store.

And plugins can package modules, API routes, workflows, subscribers, scheduled jobs, and admin extensions, which is particularly attractive if you're building reusable components across your freelance projects. docs.medusajs.com

Medusa documentation

Where Sylius beats it

If you're a strong PHP/Symfony developer, I'd seriously consider Sylius instead. Its plugin architecture is mature and designed specifically for modifying commerce behavior without changing core code. academy.sylius.com

The big advantage is that you're essentially working with a commerce-specific Symfony framework, so you get a very familiar, conventional PHP architecture rather than learning a platform-specific extension model.

Its plugin ecosystem is also substantial, covering integrations, payments, shipping, sales/conversion, analytics, accounting, etc. addons.sylius.com

Sylius

Saleor is a different flavor

Saleor is excellent if you want GraphQL + headless + external integrations.

Its model is deliberately API-first: webhooks, metadata, attributes, apps, API extensions, and dashboard extensions are the primary mechanisms for customization. docs.saleor.io

I'd choose Saleor when the client wants a highly decoupled architecture and you're comfortable treating the commerce backend more like an API platform.

I wouldn't choose it over Medusa for maximum freedom inside the backend, though. Medusa's ability to add your own modules and business logic directly into the application is a better match for "I need to make this client's commerce engine behave differently."

My practical recommendation

If you're a JS/TS freelancer, I'd standardize on:

Medusa + PostgreSQL + Next.js + your own reusable integration plugins

That gives you a nice progression:

• Normal store → mostly built-in Medusa functionality
• Custom fields/data → custom module
• External API → module/provider
• Complicated business process → workflow
• Event-driven sync → subscribers/events
• Reusable client functionality → plugin
• Custom admin functionality → admin extension

That's a very good abstraction for freelance projects because you can gradually increase customization without immediately forking the platform.

If you're PHP/Symfony-first, flip the recommendation to Sylius.

One caveat: "easiest to extend" isn't the same as "easiest to launch." WooCommerce can be faster for a conventional small store, while Medusa/Sylius start making more sense as soon as the client's requirements become integration-heavy or unusual.

For a freelance developer building custom integrations for multiple clients, I’d rank them differently than I would for a merchant choosing a store platform. You care about:

• how fast you can understand the codebase
• how safely you can add custom business logic
• how easy upgrades are after you hand it off
• how many client-specific integrations you can build without fighting the framework

My shortlist:

www.wpbundle.com

My default choice for a freelance integration shop: Medusa

If you’re comfortable with TypeScript, Medusa is probably the nicest platform to extend today. Its architecture is built around modules rather than modifying a giant monolith:

• custom payment providers
• ERP connectors
• fulfillment workflows
• subscription logic
• custom pricing rules
• marketplace features
• external inventory systems

You can keep your client-specific logic in modules instead of patching core code. That makes future upgrades much less painful. www.wpbundle.com

The tradeoff: if a client says "we need a weird local shipping carrier integration," WooCommerce might already have a plugin, while Medusa may mean you build it yourself. www.wpbundle.com

When I would pick WooCommerce instead

For many freelance projects, the fastest money is still:

WooCommerce + custom plugin + API integrations

Choose it when the client needs:

• WordPress content marketing
• lots of existing payment/shipping plugins
• nontechnical staff who already know WordPress
• a conventional online store

The ecosystem is enormous, which means fewer things you have to build yourself. The downside is that plugin quality varies and complex customizations can become a dependency-management problem. www.wpbundle.comwww.wpbundle.com

When I would pick Saleor

Pick Saleor for clients with more "application" requirements:

• multiple warehouses
• multiple channels
• complex permissions
• international commerce
• custom frontends

Its GraphQL-first approach makes integrations clean, but you’re taking on more operational complexity than Medusa. github.com

Platforms I’d be cautious about for freelance work

Magento / Adobe Commerce

• Very powerful.
• Very employable skill.
• But unless the client already lives in Magento, it’s often too much platform for a custom build.

PrestaShop

• Fine for traditional stores.
• Less attractive if your value proposition is "I build unique commerce systems."

A practical freelancer stack

If I were setting up a repeatable agency/freelance stack:

Modern custom builds

• Medusa
• Next.js storefront
• PostgreSQL
• Stripe/Adyen/etc.
• external CMS (Sanity/Contentful/Strapi)

Fast SMB builds

• WooCommerce
• custom plugin layer
• WP REST API/WPGraphQL
• managed WordPress hosting

Enterprise-ish builds

• Saleor
• Next.js
• custom integration services

For a developer whose differentiator is custom integrations, I’d probably standardize on Medusa first, WooCommerce second. Medusa lets you sell engineering capability; WooCommerce lets you ship quickly when the client mostly needs a store with a few custom touches. www.wpbundle.comwww.wpbundle.com

If your main business is building custom stores and integrations for clients, I’d shortlist Medusa, Shopware, and Saleor—with Medusa as my default pick for a freelance developer.

1. Medusa — probably the easiest for your use case

Medusa developer documentation

Medusa is particularly attractive if you're comfortable with TypeScript/Node.js. It is explicitly designed as a commerce platform plus a framework for customizations. You can add API routes, workflows, data models, modules, subscribers, scheduled jobs, and admin extensions. docs.medusajs.comdocs.medusajs.com

The architecture is nice for client work because integrations don't have to become a mess of overrides. Its commerce functionality is split into modules—products, orders, payments, fulfillment, inventory, pricing, etc.—and you can build your own modules and workflows around them. docs.medusajs.comdocs.medusajs.com

I'd choose Medusa if you typically build things like:

• ERP/PIM integrations
• custom pricing logic
• unusual checkout flows
• B2B functionality
• marketplaces
• custom fulfillment
• external subscription systems
• headless Next.js storefronts
• stores where the client's requirements don't fit a conventional ecommerce box

The big advantage for a freelancer is that you can build reusable modules/plugins and carry them between projects. docs.medusajs.comdocs.medusajs.com

2. Shopware — best if you want a mature ecommerce ecosystem

Shopware developer documentation

Shopware is probably the stronger choice if your clients want a full-featured ecommerce platform out of the box, rather than a commerce framework.

It's open source, self-hostable, API-first, and has both an app system and PHP-based plugins. Its plugins can make very deep changes to the platform, while its APIs/webhooks provide a cleaner integration mechanism. developer.shopware.com

It's built on Symfony/PHP, so if that's your stack, Shopware becomes especially compelling.

The downside: there's considerably more platform to learn. For a developer who just wants to create a highly customized store, Medusa generally feels less heavyweight.

3. Saleor — excellent if you want GraphQL/headless

Saleor documentation

Saleor is another very good choice if you're building modern headless commerce. Its core API is GraphQL, and it has explicit concepts for apps, extensions, custom data modeling, payments, shipping, marketplaces, and custom dashboard functionality. docs.saleor.io

I'd put it ahead of Medusa if your typical client says:

"We have a React/Next.js frontend and need an extremely API-driven commerce backend."

But for arbitrary backend customization, I find Medusa's modular architecture more attractive.

My recommendation for a freelance stack

I'd probably standardize on:

Medusa + Next.js + PostgreSQL + Stripe + your integration layer

and keep Shopware in your toolbox for clients who need a more established, enterprise-oriented ecommerce system.

The distinction I'd use is:

"I need to make the ecommerce platform behave differently." → Medusa

"I need a mature ecommerce platform with lots of functionality, but I need to customize it deeply." → Shopware

"The storefront is completely custom and the commerce backend should primarily be an API." → Saleor

If you're going to be doing 10+ client stores, I'd lean especially strongly toward Medusa because its modules/workflows/plugins give you a good foundation for building your own reusable integration toolkit. docs.medusajs.comdocs.medusajs.com

If your priority is “I’m a developer and need to build lots of custom integrations without fighting the platform,” I’d pick Vendure.

My ranking for freelance client work

Why Vendure stands out: its entire extension model is based around plugins. A plugin can add database entities, GraphQL queries/mutations, REST endpoints, event handlers, background jobs, custom fields, and integrations with external systems. It is built on NestJS, so if you're comfortable with TypeScript, the programming model is familiar. docs.vendure.io

For example, a client integration like:

Shopify/WMS/ERP → sync inventory → modify order workflow → add custom order fields → expose admin UI → process asynchronously

can live in a dedicated Vendure plugin rather than becoming a pile of hacks around the core.

Vendure also has strategy patterns for replacing built-in behavior without forking the platform—things like tax calculation, shipping eligibility, stock allocation, asset storage, etc. vendure.io

Vendure vs. Medusa

Medusa is the one I'd seriously consider alongside Vendure. Its architecture is also explicitly designed for customization: API routes → workflows → modules → database, with custom modules for third-party integrations. Modules can be reused between projects, which is particularly attractive for a freelancer building similar integrations repeatedly. docs.medusajs.com

I'd choose Medusa if you want to build your own reusable commerce building blocks and like its workflow/module architecture.

I'd choose Vendure if you want the least friction when modifying an existing commerce system. Its plugin system gives you a very direct way to add functionality while retaining access to the core's services, events, APIs, entities, and dependency injection.

For your specific business

If you're building stores for different clients, I'd lean:

Vendure → build a library of reusable plugins → deploy a customized configuration per client.

For example:

your-vendure-toolkit/
├── erp-sync/
├── shipping-provider/
├── custom-pricing/
├── loyalty/
├── crm-sync/
├── marketplace-sync/
├── custom-checkout/
└── client-specific/

That gives you a potentially nice freelance advantage: your integrations become reusable IP rather than one-off modifications.

If you're primarily a PHP/Symfony developer, I'd flip the recommendation to Sylius. If you're primarily Python/Django, I'd look harder at Saleor.

For a TypeScript/Node freelancer doing custom integrations, though, Vendure would be my first platform to evaluate in 2026. docs.vendure.io

If your priority is “I need to keep extending the platform for different clients without fighting the framework,” I’d put Vendure at the top of the list, with Medusa a very close second.

My ranking for a freelance custom-integration shop

1. Vendure — my pick for your use case

Vendure is particularly well suited to a freelancer building bespoke commerce backends.

Its extension model is essentially built around plugins. A plugin can:

• add/modify database entities
• add custom fields
• add GraphQL queries and mutations
• add REST endpoints
• interact with external systems
• subscribe to commerce events
• run background jobs
• replace core behavior through strategies

And it's all TypeScript + NestJS, so you're working with fairly conventional backend patterns rather than learning an ecommerce-specific extension language. docs.vendure.io

The particularly important bit for your business is that Vendure explicitly supports extending without forking the core, which makes upgrades much less painful. Its plugins also work the same way when self-hosted or on its cloud offering. vendure.io

For example, a client could need:

Shopify → ERP → Vendure → 3PL → custom pricing engine

You could make each integration a plugin, with events/jobs handling synchronization rather than hacking the ecommerce core.

Vendure even has a current guide specifically walking through building a CMS synchronization plugin, which is pretty representative of the sort of work you're describing. docs.vendure.io

2. Medusa — arguably better if you want maximum composability

Medusa is probably the other one I'd seriously consider.

Its architecture is extremely integration-friendly: API routes → workflows → modules → database. Third-party integrations are implemented through modules, and you can create your own modules for things like ERPs, CMSs, payment systems, fulfillment, etc. docs.vendure.iodocs.medusajs.comdocs.vendure.io

Its plugin system can package modules, API routes, workflows, workflow hooks, links, subscribers, scheduled jobs, and admin extensions, which is excellent if you're trying to build reusable components across multiple client projects. docs.medusajs.com

I'd choose Medusa over Vendure if your typical project looks like:

“The client has a bunch of external systems and we want commerce to be one composable service in the middle.”

I'd choose Vendure if it looks more like:

“The client needs an ecommerce system, but we're going to heavily customize the actual commerce behavior.”

3. Saleor

Saleor is very attractive if you want a GraphQL-first, headless architecture. Its ecosystem has explicit concepts for apps, extensions, dashboard customization, APIs, and self-hosting. docs.saleor.io

The tradeoff is that I find its extension model a little less natural for deep backend customization than Vendure's plugin model. It's particularly compelling when most custom functionality can live as external applications/services.

The important distinction

For your business, I'd evaluate platforms less on “how many plugins exist?” and more on:

Can I put arbitrary client-specific business logic inside the platform without modifying its source code?

That's where Vendure and Medusa shine.

For example, you might want to turn your common integrations into reusable packages:

my-commerce-stack/
├── vendure/
├── plugins/
│   ├── erp-sync/
│   ├── custom-pricing/
│   ├── shipping-provider/
│   ├── crm-sync/
│   ├── marketplace-sync/
│   └── client-specific/
└── storefront/

Then each new client becomes mostly configuration + a handful of custom plugins, rather than starting from scratch.

My recommendation: start with Vendure if you're comfortable with TypeScript/NestJS. Spend a day or two also prototyping the same integration in Medusa. If your integrations tend to be event-driven and deeply embedded in commerce behavior, I'd expect Vendure to win; if they're more like independent services stitched around a headless commerce core, Medusa may win. docs.vendure.iodocs.medusajs.comdocs.vendure.io

If you tell me what kinds of integrations you usually build (ERP, POS, shipping, subscriptions, marketplaces, custom pricing, etc.), I can give you a Vendure vs Medusa vs WooCommerce comparison specifically for a freelance agency workflow.

If your main criterion is “I need to build weird client-specific integrations quickly, repeatedly, and without fighting the platform,” I’d put Medusa at the top of the list.

My ranking for a freelance developer

Why Medusa stands out for your use case: its architecture is explicitly designed around custom modules, workflows, API routes, subscribers, providers, and admin extensions. You can package a whole integration as a reusable plugin and install it into another client's Medusa project. docs.medusajs.com

That matters a lot for freelancing. For example, you could build a reusable acme-erp-sync plugin containing:

• ERP integration/module
• product/order synchronization
• webhook subscribers
• scheduled jobs
• custom workflows
• API endpoints
• admin UI

Then reuse it across clients rather than maintaining a pile of copy-pasted modifications. Medusa specifically supports this plugin model. docs.medusajs.comdocs.medusajs.com

There's also a nice separation between modules and workflows: modules encapsulate integrations/data, while workflows let you compose business operations across modules. That is a good fit for things like “when order ships → update ERP → create accounting record → notify customer.” docs.medusajs.com

When I'd pick Bagisto instead

If you're a Laravel/PHP developer, I'd seriously consider Bagisto instead. Its core is built as modular Laravel packages, with repositories, model proxies, events, package development, and APIs intended for extension without modifying core. devdocs.bagisto.com

It's probably the more comfortable choice if your clients want a conventional ecommerce admin/store rather than a heavily headless architecture.

When I'd pick Sylius

Sylius is excellent if the projects are genuinely complex—custom pricing, unusual order lifecycles, B2B rules, multiple fulfillment concepts, etc.—and you're comfortable with Symfony. Its plugin architecture is deliberately designed to extend functionality without modifying core. academy.sylius.com

The downside for a freelancer is that I wouldn't call Symfony/Sylius the quickest learning curve compared with Medusa if you're already comfortable in modern TypeScript.

My practical recommendation

If I were building a freelance stack today:

TypeScript/React → Medusa
Laravel/PHP → Bagisto
Symfony/PHP + very complex commerce → Sylius

For custom integrations specifically, I'd start with Medusa. Its reusable-plugin model is unusually well aligned with the economics of freelancing: build an integration once, parameterize it per client, and carry it forward to the next project. docs.medusajs.comdocs.medusajs.com

If you tell me your preferred stack (Next.js/TS, Laravel/PHP, Python, etc.) and the kinds of integrations you usually build (ERP, shipping, PIM, marketplaces, subscriptions, POS, etc.), I can narrow it down to the best 2–3 options and explain the tradeoffs.

If your main business is building custom integrations for different clients, I’d pick Medusa.

My ranking for a freelance developer

Why Medusa stands out: its architecture is explicitly designed around modules, workflows, API routes and integrations. You can create a custom module for something like an ERP/CRM, use workflows to orchestrate it with orders/products, and package reusable functionality as a plugin. docs.medusajs.com

That is particularly attractive for a freelancer because you can build something once—say a Shopify → client's ERP sync—and turn it into a reusable module/plugin for your next client. Medusa explicitly supports custom third-party integrations and positions the platform as a middleware layer between commerce and external systems. docs.medusajs.com

When I'd choose the others

Sylius is arguably the strongest choice if you're a PHP/Symfony developer and expect extremely bespoke commerce logic. Its plugin system is mature and Symfony-native; plugins can extend the platform without modifying core code. academy.sylius.com

Saleor is excellent if your integrations are primarily external services talking to a GraphQL API. Its philosophy is deliberately to keep the core untouched and extend it through Apps, webhooks and API extensions. github.com

The tradeoff is that Saleor's model tends to push customization outside the core. That's fantastic for keeping upgrades clean, but if a client's requirements involve substantial changes to commerce behavior/data models, Medusa gives you a more direct framework for implementing those changes.

For your particular freelance use case

I'd lean:

Medusa → if you're primarily TypeScript/Node.js
Sylius → if you're primarily PHP/Symfony
Saleor → if you want API-first/headless and external apps doing most of the customization

If you're starting from scratch today, Medusa is probably the best "one platform I can learn and use for lots of clients" choice. Its modules and plugins are especially well aligned with building reusable integration components. docs.medusajs.com

If you tell me your preferred stack (Node/PHP/Python) and the kinds of integrations you typically build (ERP, PIM, shipping, marketplaces, subscriptions, etc.), I can narrow this down to the best 1–2 options.

If your main business is building custom stores and integrations for clients, I’d put Medusa at the top of the list.

My ranking for a freelance developer

Why Medusa: it's essentially a commerce framework rather than a rigid ecommerce application. Its architecture is split into API routes, workflows, modules, and a database layer, and you can create your own modules, workflows, API routes, links, subscribers, scheduled jobs, and admin extensions. docs.medusajs.comdocs.medusajs.com

That's particularly attractive for freelance work because you can build reusable integration packages once and carry them from client to client. Medusa explicitly supports reusable plugins containing modules, routes, workflows, hooks, subscribers, jobs, and admin extensions. docs.medusajs.comdocs.medusajs.com

For example, you could create a reusable:

• ERP integration module
• custom shipping provider
• B2B pricing module
• PIM synchronization workflow
• marketplace connector
• loyalty system
• custom checkout logic

…and install those pieces into different client projects.

Medusa vs. Sylius

I'd choose Sylius if you're a strong Symfony/PHP developer. It's exceptionally flexible because it is built as a Symfony-based framework, with plugins designed to extend functionality without modifying core code. academy.sylius.com

But if you're primarily a JavaScript/TypeScript developer, Medusa is the easier recommendation. Its Node/Postgres architecture and module system make it particularly natural for building custom integrations. docs.medusajs.com

Where Saleor fits

Saleor is probably my second choice if you prefer Python + GraphQL. It's extremely integration-friendly: GraphQL-native, headless, with a large webhook surface and extensible dashboard. saleor.io

The tradeoff is that Saleor's extension philosophy is more external/app/composable-system oriented, whereas Medusa lets you get quite deep into the commerce application's own modules and workflows.

One important distinction

If by "easiest to extend" you mean "I want to change virtually anything in the business logic", I'd choose:

Medusa → Sylius → Saleor → WooCommerce

If you mean "I want to rapidly add integrations that already have plugins", the ranking changes considerably:

WooCommerce → Medusa → Saleor → Sylius

For a freelancer doing custom client integrations, though, I'd favor the first interpretation.

My pick: Medusa. It gives you a reusable framework for turning custom client requirements into modules/plugins rather than repeatedly fighting an existing monolithic ecommerce application. docs.medusajs.com

If you tell me your usual stack (e.g. Next.js/TypeScript, Laravel/PHP, Python/Django) and the kinds of integrations you build (ERP, shipping, payments, PIM, marketplaces, etc.), I can narrow it down to the best 1–2 platforms for your agency workflow.