POS System (Windows, C# + MSSQL)
Retail POS system for small to mid-sized businesses to manage sales, receipts, and inventory.
Client/Context
Built for shop owners needing offline-ready desktop solutions; solo dev role with client feedback cycles.
Problem
Manual cashbooks and Excel sheets caused errors, delays, and no consolidated reporting.
Goals
Reduce transaction time by 50%, enable inventory tracking, generate daily reports automatically.
Role
Designed DB schema, built WPF UI, implemented sales & receipt workflows; client tested workflows.
Tech Stack
C#, WPF, MSSQL Server, Entity Framework.
Architecture
3-layer design (UI, business logic, DB) with receipt/stock modules tied to a centralized SQL DB.
Implementation Highlights
- Designed SQL schema for products, sales, and payments.
- Real-time stock decrement after each sale.
- Daily sales reports with export to Excel/PDF.
Challenges
Handling concurrent sales transactions → solved via SQL transactions + locks.
Results
Reduced checkout from ~3 mins to <1 min; improved reporting accuracy.
Timeline
~3 months (DB + UI design, testing, rollout).
Next steps
Add cloud sync & multi-branch support.