Stockpost gives every store a unique inbound email address. Suppliers send their existing stock reports (CSV or XLSX) to that address. Stockpost matches the supplier's SKUs to your Shopify catalogue, then writes the stock as native Shopify inventory at a Shopify location dedicated to that supplier. Per-supplier totals and breakdowns appear automatically across the admin, the storefront, POS, Flow, and reports — no theme code, no API integration, and nothing for the supplier to log into.