Responsibilities Maintain and enhance the backend services powering the SaaS platform (Node.js/Express/NestJS with TypeScript). Ensure uptime scalability and performance of APIs handling campaign generation template storage and credit-based billing. Optimize MongoDB queries indexes and caching strategies for high-performance APIs. Implement and manage Redis job queues and async workflows. Monitor and maintain AWS infrastructure EC2 S3 CloudWatch Lambda SES. Implement security best practices API authentication rate-limiting GDPR compliance email data handling. Maintain API versioning and documentation (OpenAPI/Swagger). Write unit and integration tests to ensure code quality and reliability. Debug and resolve complex production issues efficiently. Required Skills Strong proficiency in Node.js with TypeScript (Express.js or NestJS). Experience with MongoDB schema design and ORMs (Mongoose Prisma). Experience with Redis (pub/sub caching) and job queues (BullMQ/RabbitMQ). Familiarity with AWS services EC2 S3 CloudWatch SES Lambda. Dockerized microservices and CI/CD pipelines (GitHub Actions or similar). Knowledge of authentication & authorization (JWT OAuth2 role-based access). Basic Logging & monitoring experience (Winston Pino Prometheus/Grafana). Unit & integration testing experience (Jest Mocha Vitest). Knowledge of email compliance tools (SpamAssassin DKIM/SPF/DMARC) is a plus. Experience 3–5 years in backend development. Prior experience in SaaS applications high-traffic APIs or campaign/marketing platforms is preferred.