Migrating a 7M+ SKU consumer electronics parts catalogue to Shopify Plus is the kind of project where the easy parts look impossible and the hard parts hide in plain sight. We delivered it without losing SEO equity, customer records or order history — but with two years of hindsight, here’s what we’d do differently.
The catalogue parity playbook
Migrations at this scale fail on the edge cases, not the average row. Before touching the new store we mapped every catalogue entity — variants, customers, historical orders, collections, SEO configs, blogs, content pages, media — into a defensible Shopify Plus structure, then built parity checkpoints at every stage. Each checkpoint had a sample query that ran against both platforms and flagged any drift.
SEO preservation
SEO equity dies in 301 chains and stale canonicals. We exported every URL on the source platform, mapped it to its Shopify equivalent, and shipped a single 301 redirect map — not a fallback rule. Google’s canonical signals stayed in place because the slugs matched character-for-character where possible, and the redirect lookup table was a single hop everywhere else.
Performance at 7M SKUs
Shopify Plus handles the catalogue size, but the storefront has to be tuned. We pruned theme JavaScript, lazy-loaded everything below the fold, and pre-rendered the most common filter combinations into static collection pages. The result was a storefront that loaded as fast as a brochure site despite being backed by millions of SKUs.
What we’d do differently
The one thing we keep underestimating on these projects is the QA matrix. Every variant combination, every locale, every filter needs spot-checking. We’d front-load that QA — write the test plan before the migration script, not after.