Shopify Plus Agency for Development, Checkout and Functions

Shopify Plus is for brands that have outgrown the standard platform: more volume, more complexity, more that needs to be custom. The plan unlocks the tools, but the value is in how they are used. As a Shopify Plus agency, our job is to turn the plan you are paying for into things your customers notice and your team stops doing by hand.

A Shopify Plus agency for the technical parts

We are strongest where Plus differs most from standard Shopify: the checkout, Shopify Functions in custom apps, and the automation that ties them together. We also build and run our own checkout app, Checkout Ninja, so we work with Shopify’s checkout APIs every day, not once a project.

We have worked with more than 100 Shopify Plus brands, and we build new stores too. But if the job needs a checkout rule, a Function or a piece of custom logic that nobody else wants to touch, that is where we are most useful.

Work we have shipped

A few recent projects, and the custom logic behind them:

• Juice Plus moved 15 global storefronts onto Shopify. We built the metafield-driven cart rule that keeps subscription and one-time products apart, the same way in every store.
• Headphone Zone needed checkout to stop orders nobody could deliver. We built a sub-second PIN-code check across several courier partners that blocks the order before payment.
• A 40,000-product catalogue needed a different minimum order quantity on every product, past the limits of a rule-based Function. We stored it per product and gave the team a CSV workflow to manage it.
• A store-credit exemption joined a customer segment, two Shopify Flows and a validation Function with one tag, so customers spending store credit skip a store-wide minimum.

See all our work for the full write-ups.

How we work with Plus brands

• Discovery first. We audit your store, analytics and goals, then agree what success looks like.
• Fixed scope, clear price. You get a plan, a price and a timeline before we start, not a moving target.
• Senior hands only. The people you meet are the people who build. No juniors, no hand-offs.
• Weekly demos. Everything is built in a development store and shown to you every week before it goes live.
• Built to hand over. Clean, documented code, so you are never locked into one agency.

Engagements are usually a scoped project, such as an upgrade plan, a migration or a checkout rebuild, followed where it makes sense by an ongoing roadmap of tests and features.

Upgrading from Shopify to Shopify Plus

Moving from Shopify to Shopify Plus is a plan change, not a replatform. Your products, customers, orders and theme stay exactly where they are. What changes is what you are allowed to build: checkout UI extensions on the information, shipping and payment steps, the Checkout Branding API, and custom apps running your own Shopify Functions, plus Plus-only tools like Launchpad and expansion stores.

The upgrade only pays off if you use it. We plan it around the features that will actually move your numbers: which checkout customizations to make first, what logic to rebuild as Functions, and which apps the new capabilities let you retire.

Still deciding? Our guides to Shopify vs Shopify Plus and Shopify Plus pricing set out what changes and what it costs, with figures checked on shopify.com.

How to choose a Shopify Plus agency

Lists of top Shopify Plus agencies are a starting point, not an answer. Whoever you talk to, including us, ask:

• Can you show work like ours? Case studies in the areas you need, with the problem and the build explained, not just logos.
• Who will actually build it? Meet the developers, not only the sales team.
• Do you work with checkout extensibility and Functions in-house? Since checkout.liquid and Scripts were switched off, this is where most Plus-specific work happens.
• What do we get at the end? Documented code in an app you control, and a clear plan for who maintains it.
• Is the price fixed? A scoped quote before the build, rather than an open-ended estimate.

If those are the answers you are looking for, tell us about your store and we will come back with a plan.