QR System
Multi-tenant SaaS to generate and manage dynamic QR codes: edit the destination without reprinting the code. Sub-5 ms resolution with a Redis cache, real-time scan analytics, custom domains, a public API with signed webhooks, and Stripe billing.
Overview
QR System turns any printed QR code into an editable resource: the destination, the rules and the design change without reprinting. It is built for teams that manage hundreds of codes across campaigns, packaging and physical touchpoints.
The core is the public /r/{key} resolution: it computes the QR state (active, paused, expired, scheduled) on every request, applies per-device rules (iOS/Android/desktop) and redirects in under 5 ms thanks to a Redis cache with write-through invalidation. The scan record is queued in BullMQ so it never blocks the redirect.
A worker enriches every scan with GeoIP and user-agent, anonymizes the IP when the organization enables it, and publishes the event over Redis pub/sub to a Socket.IO gateway that updates the dashboard in real time. Cross-organization isolation is fail-closed at the database layer via a Mongoose plugin.
Gallery
