DIN 0815/M · MOD-03
Inventory Management
Stock levels, SKUs, warehouse locations, and purchase order tracking in one place.
The core correctness property: stock levels are never stored, they are derived. Every change to inventory — goods in, transfers, stocktake corrections, PO receipts — is an entry in an append-only movements ledger, and the current level of any product in any warehouse is simply the sum of its movements. There is no mutable stock counter that can drift out of sync, and the test suite proves it.
What it does
- Append-only movements ledger — levels are always derived, never stored
- SKUs, warehouse locations and per-location stock
- Purchase-order tracking with goods-in receipts
- Stocktake corrections that reconcile without overwriting history