Magic Swap Multi-Role Coupon & Discount Platform — Architectural Case Study

A digital coupon platform connecting local stores and members.

Magic Swap gives retail partners an easy way to verify customer discounts using QR codes while members access exclusive local offers.

Project Context & Overview

Similar to platforms like CouponDunia, Magic Swap required a smooth experience for both shoppers and merchants. Shop owners needed to confirm active member subscriptions instantly at checkout, while sales agents needed a tool to onboard new vendors.

Engineering Challenges

Building three separate app experiences without duplicating shared code and API communication logic.
Making QR code scanning fast and foolproof during busy retail store hours.
Handling instant SMS verification and payment gateway callbacks reliably.

Key Architectural Contributions

[01] Three Dedicated App Workflows

Created tailored Flutter apps for Members, Partners, and Salespersons, sharing a clean component library across all three.

[02] Fast QR Code Scanning

Integrated a camera QR scanner that verifies customer membership validity in less than a second.

[03] Payment Gateway Setup

Added Razorpay checkout so members can purchase membership plans directly through UPI, cards, and net banking.

[04] Push Notifications via Firebase

Set up Firebase Cloud Messaging (FCM) to send notifications whenever stores publish new offers or flash discounts.

Delivered Artifacts

Magic Swap Member Android & iOS Mobile Applications
Magic Swap Vendor & Salesperson Management Applications
Web administration dashboard with analytics and offer moderation
End-to-end Razorpay checkout and SMS verification flows

About the Author

Kartik Butani is a Senior Software Engineer specializing in scalable NestJS backends, React/Next.js platforms, PostGIS spatial data, and enterprise architectures.