Backend Engineer (Node.js) (Remote Internship - Unpaid) at CommuSync About CommuSync CommuSync is a next-generation Society Management SaaS platform that helps residential communities manage complaints, bills, visitor entries, security, notices, vendors, hyperlocal services, and more — all from a single digital ecosystem. We’re a fast-growing, early-stage Indian startup with global ambitions — and we’re inviting smart builders to join our remote team. Role Overview As a Backend Engineer, you’ll be responsible for building scalable, secure, and reliable APIs and backend services for our web and mobile apps. You’ll work closely with frontend developers, product leads, and our IoT systems team. What You’ll Do Design, build, and maintain backend services using Node.js and Express/NestJS Architect robust APIs (REST/GraphQL) for mobile/web interfaces Implement secure authentication, role-based access, and data validation Integrate payment gateways (Razorpay, Stripe), SMS/email services, and IoT event pipelines Optimize databases (MongoDB, Redis) and implement scalable microservices Participate in code reviews, system design, and CI/CD pipeline integration Collaborate with cross-functional teams to develop new features end-to-end Who We're Looking For Strong command of Node.js, JavaScript/TypeScript Proficiency with MongoDB, REST APIs, JWT/OAuth Experience with Git, Postman, Docker, and deployment workflows Understanding of security practices (HTTPS, CORS, rate limiting) Basic knowledge of Cloud Hosting (Railway, Vercel, or AWS) Ability to work independently and handle production-level code Bonus Skills Experience with IoT protocols (MQTT/WebSockets) Payment gateway integration (Razorpay/Stripe) Real-time systems, queues (Redis, RabbitMQ, Kafka) Exposure to DevOps or monitoring tools (Grafana, Sentry) What You'll Get Certificate of Internship Letter of Recommendation (LOR) Real-world project exposure & GitHub contributions Featured credit on our website and product Learning sessions, mentorship, and networking Opportunity for future paid/core team roles