We help you sell moreRequest a Free QuoteProduct configurators, custom checkouts, B2B workflows, pricing engines, and integrations, engineered on BigCommerce, Shopify, Magento, WordPress, and headless stacks by developers who own the result.
Every platform ships with a theme, an app store, and a ceiling. Custom eCommerce development is what happens above that ceiling: the feature a plugin almost does, the checkout step your business model needs, the ERP that has to see every order the second it is placed. MAK Digital has written that layer for fifteen years, on every major platform, as part of our web development services. We build it to survive platform updates, to stay fast, and to be maintainable by any competent developer, and we document it so it is yours.
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15
Fifteen years of building, migrating, and growing online stores for B2B and B2C brands.
30+
SEO, AI search, paid media, design, and development experts under one roof.
USA
A US-based core team you talk to directly, backed by vetted specialists worldwide.
4.9
Average score across 650+ verified client reviews.
Custom eCommerce development
These are the requests that arrive after a merchant has tried three apps. Each is built on your platform's APIs and templating system, so it behaves like part of the platform rather than a bolt-on.
Step-by-step builders for made-to-order, bundled, and customizable products: dependent options, live pricing, compatibility rules, previews, and cart line items that carry the configuration through checkout, fulfillment, and the ERP.
Checkout flows shaped by your business: custom fields and validation, delivery date and installation scheduling, deposits and split payments, terms and financing, age and license verification, and post-purchase steps, using Shopify Checkout Extensibility, BigCommerce checkout SDK, or Magento checkout modules.
Customer-specific price lists, tiered and contract pricing, quote requests and negotiation, quick order and bulk upload, requisition lists, approval chains, net terms, and punchout, on top of B2B platforms or tools such as B2B Ninja.
Private and public apps on the BigCommerce API, Shopify Admin, Storefront, and Functions APIs, Magento REST and GraphQL, and the Volusion API, for functionality that has to run inside the platform's admin, storefront, or checkout.
Bidirectional syncs for orders, inventory, pricing, products, and customers with NetSuite, Dynamics, SAP, Acumatica, QuickBooks, Akeneo, ShipStation, and marketplaces, built as event-driven middleware that survives spikes and retries failures on its own.
Subscription and replenishment models with custom billing rules, membership tiers with gated pricing and content, and loyalty programs with earn and burn logic tied to your margins, built on platform billing APIs or integrated with specialist tools.
Faceted navigation for complex attributes (fitment, dimensions, compatibility), year-make-model and part finders, boosted and pinned results, and merchandising rules your team controls without a developer.
Custom templates, components, and interactions on BigCommerce Stencil, Shopify Liquid and Hydrogen, Magento Hyvä, and WordPress blocks, or a headless storefront when several front ends or a bespoke experience justify it.
Admin tools, bulk operations, pricing and inventory automations, fraud and compliance rules, reporting dashboards, and workflow integrations that remove manual steps from how your team runs the store.
Build or install?
Most stores should install before they build; app ecosystems are mature and cheap. Custom development earns its cost in specific situations, and we say which one you are in before we quote. These are the cases where building wins.
When the missing piece is the pricing rule, the compatibility logic, or the checkout step that makes you different, a custom build is cheaper than working around the gap forever.
Overlapping apps for bundles, subscriptions, and pricing slow the store and break at the edges. One custom module that does what you need is faster and easier to maintain.
Off-the-shelf connectors map fields their way. When orders, inventory, and pricing must match your ERP exactly, custom middleware with your rules and your error handling is the safe choice.
App scripts stack up; a custom implementation in the theme loads what the page needs and nothing more, which is often the difference between passing and failing Core Web Vitals.
When a capability is central to the business, depending on a third-party app's roadmap and pricing is a risk. Custom code you own removes it.
Search, recommendations, and assistants that reason over your catalog, fitment, or inventory need custom integration; generic AI widgets cannot see what makes your products different.
How custom code stays healthy
The failure mode of custom eCommerce work is code that worked at launch and broke at the next platform update. Every custom feature we deliver is built to these rules so that does not happen:
We build the custom layer on the platforms we are certified on, using each one's native extension points.
Custom work runs like a product build: a scoped and priced spec, a design system, sprints with working software you can test, a launch with monitoring, and documentation and code handed over at the end.
We map the requirement, the data it touches, the platform's extension points, and the apps you already run, then confirm whether custom is the right call and write a technical scope with a fixed price.
Architecture, data model, API usage, and UX for anything customer-facing, reviewed with you before code, with edge cases and failure modes listed up front.
Development on staging in reviewed increments you can try, with automated tests written alongside the code.
Connected to payments, ERP, and the rest of your stack; tested with real products, real orders, and the odd cases that break naive implementations; performance and security checked.
Deployed through your release process with a rollback path, monitored through the first days, with your team trained on anything they operate.
Updates when the platform or an integrated system changes, monitoring, and improvements, through an ongoing support plan with the developers who built it.
Configurators, checkouts, integrations, and B2B workflows that no plugin covered. Their owners on how the custom work turned out.
Webeyecare
★★★★★
“If you're a BigCommerce user, hitting up MAKDigital is a smart move. It's a hive of skilled web designers and coders. Rest assured, they'll deliver what you're looking for.”
Trent Taucher
CEO, Budgetheating.com
★★★★★
“If I could give 6 stars I would! I have worked with Mary and MAK Digital for many years now. They have performed the Affirm Financing integration on our company website as well as many other custom coding work through the years. Pricing is fair for the level of expertise they provide and they always come through with the project quoted and timelines promised.”
PMArmory
★★★★★
“Teaming up with MAK is a total thrill! We're over the moon with our brand-new website. Alexis was all ears for our needs and hatched a plan that checked all our boxes. Her communication skills throughout the whole process were simply top-notch.”
Describe what the store needs to do and the platform it runs on. We will reply with an honest answer on build versus install, a technical approach, and a fixed price if custom is the right call.
When to build, what it costs, how it survives updates, ownership, performance, and support.
When the functionality is central to how you sell and no app matches it, when several apps overlap and slow the store, when an integration must map data exactly to your systems, when speed matters and app scripts are the problem, or when you need to own the capability rather than rent it. If an app does the job well, we will tell you to install it; our development team configures and extends apps every week.
A single well-defined feature (a checkout customization, a custom filter, a small integration) typically runs in the mid four to low five figures. Product configurators, B2B ordering systems, and ERP or OMS middleware run from the low-to-mid five figures depending on complexity. Headless storefronts and multi-system programs run higher and are scoped in phases. Every project is quoted as a fixed price after technical discovery.
Defined features take three to six weeks including testing. Configurators, custom checkouts, and integrations take six to twelve. Larger systems are delivered in phases so the first useful piece ships early. You get a dated plan with the scope and working software on staging as it progresses.
Not when it is built correctly. We build on supported, versioned APIs and the platform's official extension points (apps, modules, plugins, checkout extensions) rather than editing core files or relying on undocumented behavior, and we isolate custom code from the theme wherever the platform allows. Under a support plan we also test against platform release notes before updates reach your store.
Yes. The code, the app credentials, the repositories, and the accounts are yours, with documentation and architecture notes so your team or any developer can maintain it. We do not lock clients into proprietary frameworks.
They usually speed it up, because a custom implementation loads only what the page needs while stacked apps load everything on every page. We set performance budgets on every build and verify Core Web Vitals on mobile before release. Our speed optimization work often starts by replacing app sprawl with lean custom code.
Yes. We build bidirectional integrations with NetSuite, Microsoft Dynamics, SAP, Acumatica, QuickBooks, Akeneo, ShipStation, and others, as event-driven middleware with retries, logging, and alerts, so a failed sync is caught and repaired rather than discovered as a missing order.
Yes, on the platforms that allow it: Shopify Checkout Extensibility and Functions on Plus, the BigCommerce checkout SDK and custom checkout, Magento checkout modules, and WooCommerce checkout blocks. Custom fields, delivery scheduling, deposits, terms, verification steps, and post-purchase flows are the common requests.
Yes. Custom search and recommendations that reason over your catalog attributes, fitment data, and inventory, and assistants grounded in your products and policies, integrated through the platform APIs and measured like any other feature. We also structure product data so AI shopping agents can read it, which is increasingly where custom development and UX meet.
Most clients keep the developers who built the feature on a support plan covering monitoring, updates when the platform or integrated systems change, and improvements. If you prefer to maintain it in-house, we hand over documentation, tests, and the release process.
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