The dangerous moment is not “CSV exists.” It is when a planned import changes product or variant structure in a way that can produce identity surprises. The preflight compares two files before the import touches Shopify.
ShadowOrders product: Shopify Variant ID Risk Preflight. This page describes one specific use case; the technical boundary is the same as the underlying product.
Handles, options, variants and row relationships are not ordinary spreadsheet cells. The preflight focuses on identity risk and affected rows rather than pretending to simulate Shopify itself.
SAFE results cost nothing. When the deterministic comparison finds high-risk changes, a $0.99 detailed report is offered with affected-row evidence. Raw upload bytes are analyzed in memory and are not retained as source files.
No Shopify login and no guaranteed import outcome. This is a static preflight against the supplied CSVs.
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