HallRoastery (F&B Domain Complexity)

1. Problem

Standard retail POS systems strictly map one sale to one inventory item (1 barcode = 1 item). This model completely failed for the F&B/Cafe environment, where selling one "Caramel Latte" requires mathematically decrementing 18g of coffee beans, 150ml of milk, and 1 cup from the raw materials inventory.

2. Solution

Engineered a composite inventory and recipe management engine. The system decouples the "Finished Product" sold at the register from the "Raw Materials" stored in the warehouse, linking them via dynamic recipe mapping to calculate accurate Cost of Goods Sold (COGS).

3. Architecture

• Framework: Laravel (PHP)
• Database: MySQL
• Infrastructure: Local Server implementation

4. Key Engineering Decisions

• Laravel Eloquent ORM: Chose Laravel specifically for its robust relational mapping (Many-to-Many relationships with pivot tables). This made querying complex recipe-to-ingredient relationships highly maintainable compared to raw SQL joins.
• Multi-Stage Inventory Tables: Separated database tables into Bahan Olah (Processed), Bahan In (Raw), and Bahan Item to strictly track the lifecycle of a physical ingredient.

5. Challenges

• Database performance degradation during checkout. Decrementing 5 different raw materials for a single coffee order created heavy write-locks during peak cafe hours.
• Handling fraction-based inventory mathematics (e.g., converting kilograms to grams) without floating-point rounding errors.

6. Result

• Delivered pinpoint accuracy on raw material tracking, reducing cafe ingredient waste by over 20%.
• Provided business owners with accurate, real-time profit margins per cup sold.

7. Future Improvements

• Implement asynchronous background jobs for the inventory decrementing process to speed up the cashier's checkout transaction time.