Operator context
Longer answer
The simplest version of the answer: Klaviyo is not the thing being migrated. The Klaviyo account, the flow logic, the segments, and the historical engagement data all stay where they are. What changes is the integration that feeds Klaviyo with commerce events. Source-platform integration disconnects; Shopify-Klaviyo integration takes over.
The complication is event-schema differences. A WooCommerce "Placed Order" event and a Shopify "Placed Order" event are structurally different — different field names, different data shapes, different available properties. Flow triggers configured against source-platform event fields stop firing or fire incorrectly when the integration switches. Each trigger needs explicit re-wiring against the Shopify event schema.
The work pattern: inventory active flows during discovery, document each flow's trigger conditions and segment criteria, re-wire triggers to Shopify event equivalents during the integration build, test flow firing on staging via synthetic customer events, validate flow output before going live. Brands that skip the staging testing consistently discover broken flows post-launch as missed revenue rather than as caught issues.
Beyond flow re-wiring, the customer engagement history that powers Klaviyo segments (purchase history, lifetime value, engagement scoring) must continue to update from Shopify. The native Shopify-Klaviyo integration handles this; verify it is working in the first week post-launch by checking that recent purchases appear correctly in Klaviyo customer profiles.