Promotions, Discounts & Coupon Engine is a custom Microsoft Dynamics 365 Business Central extension that gives retail merchandising teams a single, auditable place to define every promotion and have it apply automatically — at the POS terminal, in the sales order, and through your eCommerce checkout via the BC REST/OData API.

Business Central's native sales-line discounts and price lists cover simple item and customer-group pricing, but they can't express "buy 2 get 1 free," mix-and-match bundles across an item category, threshold-based tiered rebates, or coupon codes scoped to a store, day-part and loyalty tier. This engine adds those rules as first-class records, evaluated by AL event subscribers on Sales Line validation and surfaced through a clean API for headless channels.

ECOSIRE designs the data model (promotion header/line tables, coupon tables, conflict-priority rules), writes the AL business logic, and ships it to your tenant as a per-tenant extension — no shared-code AppSource dependency, full control over your pricing rules. We install it on your environment (cloud or on-prem), wire it into your POS and checkout flow, configure permission sets, and schedule any recurring re-evaluation through the BC job queue.

This is build-to-order: it is engineered, deployed and supported by ECOSIRE on your Business Central environment — not an instant AppSource download. You get a typical delivery window of one working week, a working extension validated against your real campaigns, source-available AL handed over, and an optional support retainer for new offer types, BC version upgrades and rule tuning. Promotion application is logged line-by-line so finance can trace exactly which rule, coupon and priority produced every discount.