Multi-Platform Inventory Sync Engine
eBay, Amazon, Shopify & TikTok Shop — unified.
0
Overselling incidents after launch
−91%
Product upload time reduction
1,400+
SKUs now managed — up from ~200
4 min
To list across all 4 platforms (was 45 min)
The Problem
The client operated four completely separate storefronts — eBay, Amazon, Shopify, and TikTok Shop — managed entirely by hand. When a product sold on Amazon it stayed purchasable on every other platform until someone noticed and manually corrected the stock count. Overselling was a weekly occurrence: orders they couldn't fulfil, accumulating negative feedback, and mounting account warnings from Amazon's seller metrics team.
Listing a new product meant logging into four separate platforms, recreating the listing from scratch on each, manually mapping categories, and hoping nothing drifted out of sync. A growing catalogue of 1,400 products on a system designed for ten.
What We Built
A custom real-time inventory synchronisation engine connecting all four platforms via their native APIs. The moment a sale lands on any platform, a webhook fires, the central inventory database updates, and stock levels are pushed to all remaining storefronts within seconds. One sale on Amazon equals an instant deduction everywhere else — no lag, no manual check.
Product creation was rebuilt entirely. The seller creates a product once in a master dashboard we built — maps attributes and category per platform — and the system handles simultaneous listing creation across all four channels. Variations, bundles, and pricing tiers are managed centrally.
The Result
The seller went from spending hours daily on manual stock reconciliation to a fully automated operation. Negative feedback from overselling stopped entirely. The time freed up from manual listing went into sourcing new products — the business scaled its catalogue 7× without any additional operational headcount.