Close-up of a developer's hands typing code on a laptop

Shopify app development

Shopify apps, built like products.

From public apps to custom merchant workflows, we design and ship the product surface, backend, billing, and operational details that make an app dependable after launch.

Plan an app build

Illustrative interface

Delivery coverage

Public and custom Shopify apps

GraphQL Admin API, webhooks, and billing

Theme app, Admin UI, Checkout UI, and POS extensions

Flow, Functions, App Events, and agent-ready workflows

What the work produces

Built for the system behind the storefront.

Product architecture

A clear boundary between the Shopify surface, your backend, and the systems that own business logic.

Launch readiness

Auth, billing, rate limits, webhooks, error handling, review requirements, and operational handoff covered before release.

Long-term compatibility

Versioned integrations, safer extension deployments, and an upgrade plan that keeps the app useful as Shopify evolves.

What you can build on Shopify

Core Shopify surfaces, built as services.

We work across the main surfaces Shopify documents for developers: apps, Functions, checkout and account extensions, themes, headless storefronts, integrations, B2B and agents.

Shopify app development

Apps for the App Store or for one merchant, on the same platform our own seven apps run on.

Public App Store apps with Shopify App Pricing: monthly, annual, usage-based plans and free trials
Private and custom apps for a single store, no App Store listing
Admin apps with app home pages, admin blocks and admin actions on product, order and customer pages
Embedded apps with session-token auth, managed installation and GDPR compliance webhooks
App Store listing preparation: screenshots, pricing, support and review checklist

Functions and extensions

Server-side logic Shopify hosts, and UI that lives inside checkout, accounts, the theme and POS.

Discount Functions: custom discount types, tiered and stacked rules
Cart transform and bundle Functions
Checkout validation Functions
Delivery customization: hide, rename and reorder shipping options
Payment customization: hide or reorder payment methods by rule
Order routing location rules and fulfillment constraints
Local pickup options, pickup charges and pickup point Functions
Checkout UI extensions: upsells, custom fields, trust badges, gift messages, delivery instructions
Customer account extensions: order tracking, returns, loyalty, wishlists, subscription management
Theme app extensions: reviews, size charts, banners, timers, chat and PWA embeds
POS UI extensions: tiles and modals for loyalty, custom discounts and warranties
Flow triggers and actions so the app plugs into merchant automations
Web pixels and marketing extensions for tracking and attribution
Analytics extensions that feed app data into merchant reports

Happify works across Shopify’s main extensibility surfaces: public and custom apps, Functions, checkout and account extensions, themes, headless storefronts, integrations, B2B, AI agents, store builds and migrations.

All Shopify services

Next move

Bring the hard commerce problem.