The situation
Eleven physical stores, a growing webshop, and four systems that didn't speak to each other: storefront, warehouse management, accounting and a carrier portal. Every order crossed at least three of them — by export, email or someone re-typing it. Month-end reconciliation took a week. Peak season meant overtime spent on copy-paste.
The audit
Two weeks of logging every manual data movement produced the business case: thousands of hours a year of re-keying, plus an error term that was costing more than the labour — mispicked orders, invoice disputes, stock discrepancies. The proposal ranked every flow by annual cost and automated from the top.
What we built
An integration layer that moves every order from storefront to warehouse to carrier to invoice to ledger without human touch — except where human judgment is actually needed. Price mismatches, address anomalies and stock conflicts route to an exception queue with full context attached; everything else just flows.
The hard part
The accounting system had no usable API. The safe bridge turned out to be structured file exchange on a fixed schedule with checksum verification — boring, reliable, and fully monitored. It's a good example of a rule we hold: the best integration is the one that never surprises anyone, not the cleverest one.
Results that held
96% of orders now flow end-to-end untouched; the ops team works the exception queue instead of the whole pipeline. Data-entry errors dropped by more than 90%, month-end closes in a day, and the freed capacity was redeployed into customer service and purchasing. Payback landed within months of go-live — measured against the audit's baseline, not estimated.