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The Onyx Grid

E-commerce software studio

Shopify apps built
to a brief, not to a template.

The Onyx Grid designs and engineers commerce software for organisations: custom Shopify applications, the integrations behind them, and our own products in production today.

Apps in production
04
Platform
Shopify
Built by
One team

What we do

Commerce engineering, end to end.

Most of our work is building software an organisation cannot buy off the shelf, and then keeping it running as Shopify changes underneath it.

01

Custom Shopify apps

Public or bespoke apps built to a brief: embedded admin apps, checkout and customer-account extensions, and the Admin API work behind them. Built, submitted and maintained.

  • Embedded admin apps (Polaris, App Bridge)
  • Checkout and customer-account UI extensions
  • Shopify Functions for discounts and delivery logic
  • App Store submission and review support

02

Integrations

The unglamorous work that decides whether a store actually runs: connecting Shopify to the ERP, POS, payment, tax and fulfilment systems around it, with the failure cases handled.

  • ERP, POS and inventory synchronisation
  • Payment, tax and fulfilment providers
  • Webhook pipelines with retry and reconciliation
  • Data migration between platforms

03

Headless & storefronts

Storefronts built on the Storefront API when a theme is the constraint rather than the solution: Hydrogen or Next.js, with performance treated as a requirement.

  • Hydrogen and Next.js storefronts
  • Storefront API and metaobject modelling
  • Core Web Vitals as an acceptance criterion
  • Theme app extensions where a theme is right

04

Support & maintenance

Shopify ships changes on a quarterly cycle and deprecates API versions on a schedule. We keep apps current against it, so an upgrade is routine rather than an emergency.

  • Admin API version upgrades
  • Monitoring, alerting and error budgets
  • Performance and cost review
  • Incremental feature work

How we operate

Four things we hold to.

Built to a brief

We start from your operation, not from a settings page. If a configurable app already solves your problem, we will tell you to buy it.

Owned by one team

Design, engineering and release sit in the same team. Nothing is subcontracted, so nothing gets lost between vendors.

Correct under load

Commerce software fails at the edges: partial payments, duplicate webhooks, stock races. We design for those first, because that is where money is lost.

Yours to keep

You get the repository, the infrastructure and the documentation. No lock-in to us as a supplier.

Stack

What we build with

TypeScriptReactRemixNext.jsNode.jsGraphQLShopify Admin APIStorefront APIPolarisHydrogenPostgreSQLSupabase

Next step

Tell us what your store cannot do yet.

Send us the problem rather than a spec. We will tell you whether it needs building, and if an app already on the App Store solves it, we will point you there instead.