One inventory truth across 62 stores and a website

1 The problem

Northbank's website and its 62 stores kept separate stock counts that were reconciled overnight. Customers regularly ordered items that had sold in a store hours earlier, and staff had no view of what was available elsewhere. Cancellation rates on online orders were approaching one in six.

2 Our approach

We made stock a single real-time service that both the storefront and every till write to, with reservation on add-to-basket rather than at checkout. Where a store network drops — which it does — the till queues locally and reconciles on reconnect, with clear conflict rules that favour the physical customer standing at the counter.

3 What we built

• Real-time inventory service as the single source of truth
• Stock reservation at basket, released on timeout
• Offline-tolerant POS with conflict resolution on reconnect
• Click-and-collect and ship-from-store fulfilment
• Search and merchandising through Algolia
• Load tested to 14× average traffic before peak season

4 Technology