Inventory Managment system (React+nest.js)

Architected and implemented a full-stack inventory and invoicing platform with a RESTful NestJS API and a React/TypeScript

frontend, modeling 9 relational entities (Items, Invoices, Payments, Returns, Stock Movements) with enforced referential integrity

and transactional consistency across all financial operations.

• Designed a compute-on-read architecture where all balances and totals (customer/supplier balances, invoice status, outstanding

amounts) are calculated live from source data rather than cached, eliminating data-drift risk across the entire system.

• Engineered automated, transaction-safe business logic linking invoices and returns directly to inventory and financial ledgers,

ensuring every stock change is traceable to exactly one originating document; validated end-to-end through 100+ manual and

automated API test scenarios.