Service Custom Apps
Typical Timeline 6–12 Weeks
Team Senior, 3–4 People
Source Platforms Remix · Gadget · Polaris · GraphQL

Custom Apps

Shopify apps that earn their keep, public or private.

Every high-volume Shopify Plus store eventually hits a ceiling with off-the-shelf apps. We design and build private Shopify apps, custom API integrations, and backend systems that fit your business exactly. Our team works with the Shopify Admin API, Storefront API, Shopify Functions, and Checkout Extensibility to extend your store's capabilities without compromising platform stability. Common engagements include ERP and 3PL integrations, custom pricing and discount logic, and bespoke loyalty systems all built to Shopify's API versioning standards and designed for long-term maintainability.

The work

When the App Store doesn't have what you need.

There are 13,000 apps in the Shopify App Store. None of them do the thing your business actually needs or one of them does it badly, expensively, and with a UI your team hates.

Seedcms builds custom apps for merchants who've outgrown off-the-shelf, and for partners shipping commerce products into the Shopify ecosystem. Embedded admin tools, public App Store launches, private partner integrations.

Built on Remix, Gadget, or whatever the stack demands. Polaris-native UI. OAuth, GDPR, and security review handled.

What's included.

What a Custom App Development engagement covers the scope, the deliverables, and the operational reality of shipping each piece.

01

Public App Store apps

Public-listed apps for partners shipping commerce products to the Shopify ecosystem. End-to-end: development, submission, security review, launch.

  • App Store submission & review
  • GDPR & mandatory webhooks
  • Built-in OAuth + scopes
  • Polaris-native UI
02

Private merchant apps

Bespoke apps installed on your store and yours alone. The functionality the App Store doesn't have, built to your spec, owned by you.

  • Custom admin UI in Polaris
  • Webhooks + GraphQL Admin API
  • Shopify Functions where it fits
  • Code & infra fully owned by you
03

Embedded admin tools

Internal tools that live inside Shopify Admin merchandising dashboards, ops consoles, custom reporting, bulk operations.

  • Embedded App Bridge UI
  • Bulk operations + jobs
  • Custom reports & exports
  • Role-based access

Our approach.

How we run a Custom App Development engagement. Sequenced so each phase de-risks the next.

Step 01

Define

Use cases, scope, App Store vs private, distribution model, integration surface. Output is a spec lean enough to ship and complete enough to ship safely.

Step 02

Architect

Stack decisions Remix vs Gadget vs custom, hosting, data model, webhook strategy, scaling profile. Designed for the load you'll actually hit.

Step 03

Build

Senior engineering on a small team. Polaris-native UI from day one. CI, monitoring, error tracking wired in before the first feature ships.

Step 04

Submit

For public apps: App Store submission, security review, listing assets, screenshots, install flow. We've taken apps through review we know what they'll catch.

Step 05

Launch

Public launch with merchant onboarding flow, support docs, billing wired up. Or private install with admin training and runbook.

Step 06

Maintain

Shopify APIs evolve. We stay on for ongoing maintenance API version upgrades, security patches, feature shipping usually as a monthly retainer.

0
Apps shipped to production
Public & private
0
App Store approved
Through security & review
0
Polaris-native UI
Embedded in Shopify Admin

Stack we trust.

Tools and partners we deploy on Custom App Development engagements. Certified, integrated, and chosen on purpose.

Selected apps

Clients we've shipped apps for

01 04

Honest answers.

The questions we get about Custom App Development before brands sign. If yours isn't here, ask us directly.

Public app or private app?

Public when you're a partner shipping a commerce product to the broader Shopify ecosystem you want listing, distribution, recurring billing, and the App Store as a sales channel.

Private when you're a merchant who needs functionality the App Store doesn't have, installed on your store and yours alone. No listing, no review queue, full control over the codebase.

How long does App Store approval take?

Submission to live is usually 2–6 weeks depending on the review queue and how clean the submission is. We've shipped apps through review enough times to know what they'll catch OAuth scoping, GDPR webhooks, billing flow, dispute handling.

We build to those requirements from day one so resubmissions are rare.

Who owns the code?

You. Full stop. Code lives in your GitHub, infrastructure on your accounts, all IP transferred at launch. We've never built a vendor-locked client app and we never will.

What backend do you build on?

Stack-agnostic. We default to Remix for most builds (Shopify's official recommendation, great DX, scales well), Gadget when speed-to-market matters more than custom infra, and bespoke Node/Python stacks when the requirements demand it.

We'll make the recommendation in week one based on your scale, team, and roadmap.

Will you maintain it after launch?

Most clients move to a monthly retainer with us post-launch Shopify APIs ship breaking changes, security patches need shipping, features keep coming. If you have in-house engineering we transfer cleanly with documentation and a knowledge-transfer week.

Can you integrate with our existing internal systems?

Yes. Custom apps are often the bridge between Shopify and the rest of your stack ERPs, OMSs, warehouse systems, BI warehouses, internal admin tools. Webhook architecture, queue design, error recovery all in scope.

Let's build

Tell us where you want commerce to go.

30-minute intro call. No deck, no sales theater just senior people, your roadmap, and an honest answer on whether we're the right fit.

Book an intro call