As a Backend Developer (MERN Stack) at AiSensy, you will play a key role in building scalable, high-performance systems to power real-time communication and large-scale marketing automation. You'll work closely with product managers, frontend developers, and DevOps to architect reliable backend services that scale seamlessly and perform under heavy load.

This is a high-impact opportunity to shape the backend infrastructure of one of India's fastest-growing SaaS platforms.

Key Responsibilities :

- System Design & Scalability : Design and implement distributed systems that can process millions of daily WhatsApp messages.

- API Development : Develop and maintain RESTful APIs for web and mobile applications, ensuring speed and security.

- Backend Architecture : Write efficient, modular, and reusable code in Node.js with Express.js.

- Database Management : Build and optimize MongoDB schemas and queries for scalability, reliability, and performance.

- Performance Optimization : Identify and fix bottlenecks in performance, memory, and latency through monitoring and refactoring.

- Security & Compliance : Implement data security and protection best practices throughout backend services.

- DevOps Collaboration : Work with DevOps to ensure robust CI/CD pipelines and cloud infrastructure (AWS, Docker, etc.).

- Team Collaboration : Collaborate with frontend, product, and QA teams to ship features rapidly without compromising stability.

- Code Quality : Participate in peer reviews, write clean documentation, and follow development standards.

Qualifications :

Must-Haves :

- 5+ years of overall software development experience, with 3+ years in backend development using MERN stack.

- Strong proficiency in Node.js, Express.js, MongoDB, and REST API development.

- Deep understanding of asynchronous programming, promises, and event-driven architectures.

- Hands-on experience with Git, Docker, and AWS-based deployments.

- Solid understanding of data modeling, indexing, and performance optimization in MongoDB.

- Experience with production-level systems handling large volumes of traffic and users.

- Familiarity with logging, monitoring, and debugging tools for backend systems.

- Excellent problem-solving skills and strong communication abilities.

Nice-to-Haves :

- Experience with Redis, message brokers (like RabbitMQ), or pub/sub systems.

- Understanding of WebSockets or real-time data pipelines.

- Knowledge of container orchestration tools like Kubernetes.

- Exposure to GraphQL or serverless technologies.

- Experience working in fast-paced SaaS product teams.