Senior full stack Developer for Incomplete Platform

Senior Backend Developer Required (Long-Term) – Existing Platform Needs Completion

We are looking for an experienced Senior Backend Developer to join our team on a long-term basis.

Our previous developer completed only the basic foundation of the backend, but the project is far from production-ready. We're looking for someone who can take ownership of the architecture, finish the remaining modules, and continue maintaining the platform.

What Has Already Been Completed
User registration & authentication
Phone OTP login
JWT access/refresh authentication
Customer profile
Locations
Locker units
Individual lockers
Bookings
Pricing rules
Wallet and basic payment records
Support tickets
Scheduled booking/status jobs
Basic IoT/Firmware communication placeholders
Basic Admin/Web Portal APIs

These modules exist but represent only the initial implementation.

What Still Needs to Be Built
Multi-Tenant Architecture
Proper organization isolation
Company-level data segregation
Multi-tenant permissions
User & Permission Management
Management accounts
Client accounts
Support accounts
Employee accounts
Granular roles and permissions
ERP & Business Features
Employee records
Company ERP integration
Client feature flags
Office locker management
Permanent locker assignments
Shift-based locker allocation
Customer Support
Live support agent routing
Ticket workflow improvements
IoT & Smart Locker Features
Customer verification before remote opening
Device command lifecycle
Command acknowledgements
Door Open / Door Close event handling
Physical confirmation events
Command idempotency
Event sequencing
Unit activation keys
Controller identity & authentication
Heartbeats
Offline/stale device detection
Firmware Management
Firmware inventory
OTA firmware campaigns
Rollout & rollback
Signature verification
Monitoring & Infrastructure
Redis queues
WebSocket / MQTT architecture
Production monitoring
Scaling & performance optimization
Security audit logs
Operational logs
CMS & Administration
Media & Advertising CMS
Advanced Admin features
Quality & Documentation
Unit & Integration tests
Complete OpenAPI/Swagger documentation
Postman collection
Production-ready API documentation
Ideal Candidate
5+ years of backend development experience
Strong experience with Node.js/NestJS (preferred)
Experience with PostgreSQL, Redis, Docker
Experience building multi-tenant SaaS platforms
IoT/MQTT/WebSocket experience
REST API architecture
Authentication & authorization
Production system architecture
CI/CD knowledge
Excellent communication skills
Important

This is not a greenfield project. You'll be taking over an existing codebase and completing it to production quality.

Please include:

Similar backend or SaaS projects
IoT or MQTT experience (if any)
Experience with multi-tenant architectures
Estimated availability (hours/week)
Expected monthly or hourly rate

We're looking for a long-term technical partner who can own this project and grow with our team.