Home Services Shopify appsTheme app extensions

Blocks merchants place themselves.

We build theme app extensions with app blocks and app embeds, so merchants add your features through the theme editor and their theme code is never touched.

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No theme code edits
Fast storefront loading
Clean on uninstall

Extension build

Working

App block schema definedDone
Settings mapped to theme editorDone
Tested on Dawn and HorizonDone
Storefront performance checkLive
Deep link to app embedNext

Apps that inject code into themes slow stores down, break during theme updates and leave code behind after uninstall. We build with app blocks and embeds, so Shopify loads, places and removes your features cleanly.

Storefront features, done properly.

Theme app extensions are Shopify's supported way to add app features to Online Store 2.0 themes, and we use every part of them.

App blocks

Pieces of your feature, like reviews or size guides, that merchants drag into product, collection or cart templates and arrange themselves.

App embeds

Floating or site-wide features such as chat, pop-ups or tracking scripts, which merchants switch on with one toggle in the theme editor.

Merchant settings

Colours, text and layout options exposed in the theme editor, so merchants match your feature to their brand without code.

Liquid and metafields

Blocks render with Liquid and read your app's data from metafields, so content shows quickly without extra calls from the browser.

Light assets

Small, deferred JavaScript and CSS served from Shopify's CDN, so your feature adds as little as possible to page load.

App proxy pages

Pages on the store's own domain, such as a wishlist or quiz results, served from your app through a Shopify app proxy.

Done properly.

The details that decide whether theme app extensions pays off.

Tested across popular themes.

Themes structure their templates differently, so we test each block on Shopify's free themes and the paid themes your merchants use most. We check desktop and mobile, the theme editor preview and Lighthouse scores before release.

Themes and checks

DawnHorizonRefreshSenseCraftStudioPrestigeImpulseTheme editorLighthouseTheme Check

Setup without a support ticket.

After install, the app links merchants straight to the theme editor with your embed ready to switch on. A short in-app guide shows where to place each block, and the app confirms when it is live.

AI support draft

Example

The size guide is installed, but its app block is not on the product template yet. This link opens the theme editor in the right place. Drafted for a person to check before sending.

Checked by a person before it goes out

How it works.

Clear steps, and you approve each one before we move on.

01
Plan
We decide which features become blocks, which become embeds and what merchants can change.
02
Build
We write the Liquid, settings and assets, served through Shopify's app framework.
03
Test
We test across themes, devices and the theme editor, checking speed each time.
04
Release
We deploy the extension with Shopify CLI and update your setup guide.

Example project

A reviews app replacing injected code with app blocks

The app adds review widgets by injecting code into theme files. Merchants report broken layouts after theme updates and leftover code after uninstalling, and the developer wants to meet Built for Shopify requirements.

What we would do

Rebuild widgets as app blocks and an embed
Move review data into app metafields
Add theme editor deep links to setup
Test on popular free and paid themes

An illustration of how we would approach it, not a client result.

What you would get

A theme app extension for reviews
Merchant settings in the theme editor
Migration guide for existing merchants
No leftover code after uninstall

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Questions, answered.

What is a theme app extension?

It is Shopify's supported way for apps to add features to a storefront. Merchants add app blocks and embeds in the theme editor, and Shopify handles loading and removal.

Will it work with the merchant's theme?

App blocks work in any Online Store 2.0 theme section that accepts them, and app embeds also work in older vintage themes. We test on the themes your merchants use and advise on any gaps.

Do theme app extensions slow the store down?

They are designed to keep stores fast. Assets load from Shopify's CDN, and we keep scripts small and deferred. We test page speed on real themes before every release.

Can you convert our existing script tags?

Yes. We rebuild script tag and theme file features as blocks and embeds, then help existing merchants switch over with a guide and in-app prompts. Old code is removed carefully.