Manhead Merchandise runs Shopify storefronts, touring sales on atVenu, a ShipHero warehouse, retailers like Zumiez and Hot Topic, FedEx, UPS and USPS, and payment processors behind all of it.
The move was ShipHero into NetSuite: twenty years of orders, inventory and adjustments. The hard part isn't the volume. It's returns that point back at orders from years ago, SKUs that changed names, and balances that are really liabilities.
No big-bang cutover. The old system and the new one ran side by side, the same day's orders landing in both.
A comparison report by period and by channel: order count, units and dollars, old side next to new side. Every row either ties or it doesn't.
The rows that don't tie go to an exception file, each one named: which record, which side, how far off. A person decides every one. Nothing is marked close enough.
Nothing was turned off until the report came back clean across a full close. Then the old system went dark, and the report kept running after that to prove the new side held on its own.
I led the move, and I still run 11 live systems for Manhead today.
