What is your Plus plan doing that standard Shopify couldn't?
Checkout Extensibility, custom Shopify Functions, B2B, expansion stores and the higher API limits all come with the plan. Every one of them has to be built before it does anything for your customers.
Fontis is a Melbourne-based Shopify Partner. We write the extensions, Functions and integrations that turn the plan into a storefront.
What Plus adds over standard Shopify
Shopify Plus is the same platform with a different set of extension points unlocked. These are the ones that change what can actually be built.
Checkout Extensibility
Plus is the tier that opens up the checkout itself. Other plans can only extend the thank you and order status pages. On Plus, custom fields, delivery instructions, verification steps and conditional content sit inside the information, shipping and payment steps themselves.
Shopify Functions
Functions run custom logic inside Shopify's own backend rather than in browser scripts, covering discounts, shipping and payment method customisations, cart transforms, and validation rules. Any plan can use Functions that come packaged inside an App Store app, but writing your own through a custom app requires Plus. On Plus you can encode pricing rules that are specific to your business.
B2B on Shopify
Company profiles, payment terms and volume pricing are available on every Shopify plan from Basic up, with a limit of three B2B catalogues. Plus removes the limit, so each company can have its own catalogue and price list, and adds deposits and partial payments. For wholesalers running a separate B2B platform alongside retail, that is often what lets Shopify replace it.
Expansion Stores and Markets
Plus includes additional storefronts under one plan, which suits brands running separate stores per region, per brand, or splitting retail from wholesale. Combined with Markets, it covers multi-currency, multi-language, and market-specific catalogues and pricing.
Higher API Limits
Plus raises the rate limits on the Admin API substantially. That matters most for a store syncing a large catalogue with an ERP, where a throttled integration falls behind during peak trading and needs constant attention to keep it current.
Organisation Admin
The Plus organisation admin handles user management and permissions centrally across every store on the plan, so staff access is administered once instead of store by store. For a brand running several storefronts, that is what keeps the admin overhead from multiplying with each one.
What we build on Plus
Fontis works directly with the Plus developer surfaces. Every engagement starts by mapping what the store needs against what the plan already provides.
Checkout Builds and Migrations
Checkout UI extensions for delivery instructions, gift messaging, custom fields, age or licence verification, and B2B purchase order references. For stores still carrying legacy checkout customisations, we scope the rebuild against Checkout Extensibility and take the opportunity to drop whatever no longer justifies the maintenance.
Custom Discount and Shipping Logic
Functions for tiered and conditional discounts, bundle pricing, margin safeguards, freight rules based on weight or zone or product type, and payment method restrictions. We will tell you first whether an existing app already covers what you need, and build a custom Function only where it does not.
B2B Implementation
Company account structures, per-customer price lists, payment terms, and the storefront changes that a wholesale buyer needs. Where an ERP holds the authoritative pricing, we connect it so the price lists stay accurate without manual maintenance.
ERP and Systems Integration
The higher API limits on Plus change what the integration architecture can look like. We build end-to-end integrations covering products, variants, inventory, orders, customers, vouchers, and refunds, including our semi-custom AP21 integration for fashion retailers.
Why Fontis for Shopify Plus
Engineering Depth
Fontis is an engineering agency with 20 years of commerce platform work behind it. We follow Checkout Extensibility, Functions and the Plus roadmap as changes ship, so what we build stays aligned with where the platform is going.
App Developers Too
Our promotions engine, Deducto, is published on the Shopify App Store. Building and running our own app means we work with Shopify's app and extension surfaces as a vendor, as well as on behalf of the merchants we build for.
Australian Retail Context
We work with GST handling, Afterpay and Zip, local carriers, and the operational realities of Australian multi-channel retail every day. Our team is based in Melbourne and builds for this market directly.
How a Plus engagement runs
Assessment
A review of the store against what the plan provides: which Plus features are in use, what the app stack is doing that the platform could do natively, the state of the checkout, and where the integrations sit relative to the available API headroom. You get a written summary whether or not you engage us further.
Scope and Build
Work is scoped into defined pieces with fixed outcomes, so you know what each stage delivers before it starts. Development happens in a development store or an unpublished theme, with extensions and Functions tested against real order scenarios before anything reaches the live store.
Launch and Support
Deployment is coordinated around your trading calendar. Afterwards, support comes from the engineers who built the work, with retainer options covering ongoing development, platform changes, and peak trading readiness.
Common questions about Shopify Plus
Do we actually need Plus, or will standard Shopify do?
It depends on what you are trying to build. If you need checkout customisation, company-specific B2B catalogues, multiple storefronts under one plan, or you are hitting API rate limits on an ERP integration, Plus is the tier that unlocks those. If none of those apply, standard Shopify with good engineering will usually serve you better than Plus with none. We will give you a straight answer on this before you commit to an upgrade.
We have legacy checkout customisations. What happens to them?
They need rebuilding against Checkout Extensibility, since Shopify has retired the older customisation model. We audit what the existing checkout does, confirm with you which behaviours are still wanted, and rebuild those as checkout UI extensions and Functions. It is a good chance to simplify at the same time.
Can you handle B2B and retail on the same store?
Yes. Shopify supports B2B alongside direct-to-consumer, either on the same storefront with buyer-specific catalogues and pricing, or, on Plus, as a separate expansion store. Which structure suits you depends on how different the two catalogues and customer experiences need to be, and that is one of the first things we work through.
Do you work with our existing theme and apps?
Yes. Most engagements start with a store that already exists. We work within whatever theme and app stack is in place unless there is a clear reason to change something, in which case we make the case and let you decide. If performance is the concern, our Shopify performance service is a better starting point than a rebuild.
Thirty minutes with a Shopify Plus engineer
We go through your store, your checkout, and the parts of Plus you are paying for but not using. No pitch deck, and no obligation to go further.