StockGate is a unified Inventory & POS system for a single-building retail facility with two zones — a Basement (storage/receiving) and a Shop Floor (sales). It replaces paper-and-memory tracking with digitally-signed, role-gated workflows so every movement of stock is authorised, attributed, and auditable.

The Problem It Solves

Before StockGate, inventory was tracked manually, which produced unexplained missing goods, zero accountability for who moved what, and no digital audit trail from supplier intake to customer sale. StockGate closes all three gaps by making every inventory mutation an atomic, role-checked, logged operation.

Key Capabilities

• Role-gated workflows: Four roles (GM, Admin, HR, Staff) gate who can create products, move stock, and approve transfers.
• Transfer request lifecycle: Basement→Shop Floor moves flow through a Pending → Approved / Rejected → Completed workflow with JSONB item lists.
• Atomic mutations: All stock changes run as PostgreSQL stored procedures (SECURITY DEFINER SET search_path = public), giving transactional guarantees and eliminating TOCTOU race conditions. Insufficient stock raises an exception and rolls the whole transaction back.
• Immutable audit log: Every action is recorded with user attribution and timestamp; inventory can never go negative (quantity >= 0 enforced by a DB CHECK).
• Barcode-indexed catalog and persistent in-app notifications (capped per user).
• Production-ready: Ships with a passing test suite (83/83).

Data Model (6 tables)

users (4 roles, soft-delete) · products (unique indexed barcode) · inventory (per-zone, quantity >= 0) · transfer_requests (JSONB item lists) · audit_logs (immutable) · notifications (capped at 50/user). Constraints — CHECKs, foreign keys, and unique indexes — are enforced at the database level, not just in application code.

Tech Stack