GatiNow

Multi-tenant scheduling SaaS

• NestJS
• PostgreSQL
• Redis
• Stripe
• PayPal
• Razorpay

GatiNow is a multi-tenant scheduling SaaS built for businesses that take bookings - branded booking pages, tier-based plans with feature-level access control, and horizontally scalable backend APIs behind it all.

The core problem was concurrency: a timezone-aware booking engine has to prevent double-booking across simultaneous requests without locking the whole system up. That's handled with PostgreSQL row-level locking and an approval-workflow layer, so two people can't accidentally book the same slot even under load.

On top of the booking engine sits a unified integration layer: multi-provider payments (Stripe, PayPal, Razorpay), two-way calendar sync (Google, Outlook, Zoho), and meeting tools (Zoom, Teams) - all normalized behind one workflow rather than bolted on as separate integrations.