Mobile App
The Problem
Multi-location businesses like restaurant chains manage employee schedules in spreadsheets, track hours manually, and have no real-time visibility into who's clocked in across locations. Payroll is error-prone and compliance is a guessing game.
How It Works
Ctrl:Shift is a monolithic Node.js/Express backend serving both a React 19 web app and a React Native iOS app. The backend uses MongoDB with 26 Mongoose models, all enforcing multi-tenant isolation via organizationId on every document.
The real-time shift calendar uses Socket.IO with dedicated namespaces for calendar collaboration and general notifications. Multiple managers can edit the same calendar simultaneously. The system handles conflict resolution, optimistic UI updates, and undo/redo history per session.
Deployment runs on a self-hosted Hetzner VPS with Docker containers, Nginx reverse proxy, and a blue-green deployment pipeline via GitHub Actions for zero-downtime releases.
The platform ships continuously (v2.23, 2,700+ commits): recent additions include an extra-pay/special-rate engine with recurrence rules, cross-location work-distribution reporting, and hard-locking of approved months across both REST and Socket.IO.
Key Challenges
Real-time calendar collaboration with multiple managers editing simultaneously
Built Socket.IO session management with optimistic UI, server-side validation, conflict detection, and per-client undo/redo history. Failed operations broadcast reverts to all connected clients.
Multi-tenant data isolation across 26 models
Every data-bearing model includes organizationId. Middleware validates req.user.organizationId against the resource on every request. Repository pattern ensures consistent data access.
Timezone-aware scheduling across locations
All times stored in UTC. Auto-detect location timezone via geo-tz library. Convert to/from local time at API boundaries with dedicated conversion functions.
GDPR compliance (Art. 20, 33, 5)
Immutable audit logs with TTL auto-deletion, automated breach detection via hourly scheduled job, portable JSON data export endpoint, and consent tracking at registration.
Location-based clock-in enforcement
GPS geofencing on the mobile app verifies employees are physically at the assigned location before allowing clock-in. Configurable radius per location, with managers able to override when needed.