Theme Companion and Shopify's built-in updates

What Shopify's built-in theme update does with your customizations, what Theme Companion does differently, and what changes after your first update with the app.

How Shopify's built-in update works

When a new version of a Theme Store theme is released, Shopify lets you add an updated copy to your draft themes. Customizations made in the Theme Editor — settings, layouts, section and block settings, new templates — are always carried over.

Code edits are a different story. If you (or an app) edited theme code, Shopify includes those edits only when they don't conflict with the update. If they do, the theme is added with the message "code edits could not be included" — and it's up to you to find your edits and copy them into the new version by hand. Shopify's documentation suggests using a diff app to identify what you changed.

So the built-in update works well right up to the moment your code edits and the new version touch the same code — and that's exactly where it stops helping.

What Theme Companion does differently

Theme Companion is built for that moment. Instead of dropping your code edits when they conflict, it merges your theme with the new version file by file and turns every overlap into a conflict you decide explicitly. That changes three things:

• Conflicts are decided, not dropped. The built-in update stops at "code edits could not be included" and leaves you to find and re-apply your changes by hand. In Theme Companion, everything that doesn't conflict is still carried over — and each conflict is shown to you with both sides visible.
• You can combine both changes. For each conflict: keep yours, take the new version's, or edit and merge them — keeping your customization and the vendor's improvement. That third outcome doesn't exist in the built-in update at all.
• Nothing is dropped silently. Every edit is either carried over or shown to you as a decision, and you confirm the final result — the guarantee the built-in update can't make.

What this doesn't mean: it doesn't make every decision effortless. A conflict exists because you and the theme vendor changed the same code in different ways — no tool can know which result you want. Most conflicts resolve with a click; a few need a closer look. The hardest cases come from distance: while you keep customizing your theme, the vendor keeps releasing new versions — often monthly. The longer updates are postponed, the further the two sides drift apart, and some customizations may eventually need to be re-applied in the new version's structure. See When conflicts get hard — and keep in mind that in every one of those cases, the built-in update would simply have left your edits behind.

At a glance:

Scenario	Shopify's built-in update	Theme Companion
Theme Editor customizations (settings, layouts, templates)	Carried over	Carried over — never rewritten
Code edits that don't conflict	Carried over	Carried over
Code edits that conflict	Not included — you re-apply them by hand	Shown as conflicts you decide, side by side
Keeping your edit and the vendor's change in one place	Not possible	Edit and merge them in the conflict

After you update with Theme Companion

A theme created by Theme Companion is technically an uploaded theme, and Shopify treats all uploaded themes the same way:

• The theme card in your Online Store no longer shows update notifications for new versions.
• Shopify's automated updates no longer apply to this theme.

This is a Shopify platform rule for all uploaded themes, not something an app can change. In practice it changes one habit: your next updates come from Theme Companion, not from the Online Store. Open the app to see when a new version is available and run the update from there.

And nothing is lost in the trade: for a customized theme, the built-in update was never the safe path — it carries code edits only while they don't conflict. Theme Companion carries your customizations through every update, and shows you anything that needs a decision.