Zeus, our Shopify theme framework, now powers every build we ship.

Code Migrator

Legacy theme modernisation

Turn a decade-old theme into Online Store 2.0 without starting over.

Oldest theme it handles
2015Oldest theme it handles
Rollback on every run
1 clickRollback on every run
Nothing written unapproved
Diff firstNothing written unapproved

Themes brought up to 2.0

HaldenKylie Cosmetics

Code Migrator parses vintage Liquid, finds deprecated patterns and generates the sections, blocks and schema needed to bring the theme up to current standards — with a diff you approve before anything is written.

  • 01

    Liquid analysis

    Scans the theme for deprecated tags, filters and objects Shopify no longer supports.

  • 02

    Section conversion

    Rewrites static includes and snippets as sections with blocks and JSON templates.

  • 03

    Metafield mapping

    Migrates legacy namespace metafields onto current definitions and metaobjects.

  • 04

    Diff preview

    Every change is proposed as a reviewable diff. Nothing is written until you approve it.

  • 05

    Safe rollback

    Snapshots the theme before each run so any migration can be reverted in one click.

  • 06

    Audit report

    An exportable report of what changed, what needs manual work and what was skipped.

How it works

Propose, review, then write

  1. 01

    Scan

    Parses the theme for deprecated tags, filters and objects Shopify no longer supports, and reports what will need a human.

  2. 02

    Propose

    Generates the sections, blocks and JSON templates the theme is missing, as a diff. Nothing is written yet.

  3. 03

    Review

    You approve the diff file by file. Anything you reject stays exactly as it was.

  4. 04

    Apply or roll back

    The theme is snapshotted before each run, so a migration you regret is one click away from undone.

Quotes for rebuilding our theme started at forty thousand. Code Migrator got us to Online Store 2.0 in a fortnight, and the diff review meant we understood every change it made.
Halden

Theo BarnesFounder

At a glance
Surface
Embedded admin app
Coverage
Vintage themes back to 2015
Safety
Snapshot + one-click rollback
Output
Reviewable diffs, exportable audit
Built with
LiquidShopify CLIAdmin APIJSON templates
FAQ

Code Migrator, answered

Sometimes. If the theme's structure is sound and the problem is age, it gets you current for a fraction of a rebuild. If the architecture itself is the problem, the audit report will say so.

You see every change as a diff before anything is written, and the theme is snapshotted before each run. Reject the file, or roll the whole run back.

Vintage themes back to around 2015. Older than that and the audit report usually recommends a rebuild rather than a migration.

Anything requiring a judgement call — bespoke JavaScript, third-party integrations and heavily customised checkout logic. Those are listed in the audit report as manual work rather than silently skipped.

Code Migrator

Install it, or ask for more

Install it from the Shopify App Store, or tell us what it doesn't do yet — most of our work is the custom half.

Start a project

Build it with us

Tell us what you're shipping. We'll come back with an approach, a timeline and a fixed scope.