/Busly.

Busly is a cloud-based SaaS developed for businesses running multiple merchants across different markets. Before it existed, teams were stitching together outdated tools or spending months on custom builds. I developed the full stack — Django backend, React frontend, PostgreSQL database — with a decoupled architecture that scales each layer independently and a five-tier role hierarchy that enforces access boundaries at every level, not just the UI.

The core challenge was threefold — build a permission system that mirrors how real payment businesses operate, integrate a payment gateway layer that handles multiple currencies and markets without custom code per gateway, and make the platform embeddable so merchants can drop modules directly into their own products. Every technical decision had to hold up under real financial transaction load with full audit accountability.

Delivered a complete Django REST backend with role-scoped API enforcement across all five user tiers — SuperAdmin through MerchantStaff. Gr4vy integration handles payment creation, status tracking, refund processing and webhook-driven real-time updates with no polling. JWT-verified iframe modules let merchants embed transaction history and payment forms into their own platforms securely. Every action in the system — payments, role changes, logins — is captured in audit logs. Production deployment configuration included on handover.