Worked extensively with MongoDB, PostgreSQL, and MySQL, designing schemas and developing a large number of REST APIs for scalable, production-grade applications. • Designed and implemented a scalable notification system using Firebase and RabbitMQ, handling bulk notifications. • Integrated multiple payment gateways (PayFort, Stripe, TAP) with proper validation, webhooks, and error handling. • Worked on live production systems, diagnosing and fixing performance issues, bugs, and edge cases. • Implemented Redis-based caching and session management to improve performance and optimize database. • Built backend systems using both microservices and monolithic architectures, ensuring maintainability and scalability. • Designed and developed hundreds of scalable REST APIs using Node.js and TypeScript for production-grade applications.…Worked extensively with MongoDB, PostgreSQL, and MySQL, designing schemas and developing a large number of REST APIs for scalable, production-grade applications. • Designed and implemented a scalable notification system using Firebase and RabbitMQ, handling bulk notifications. • Integrated multiple payment gateways (PayFort, Stripe, TAP) with proper validation, webhooks, and error handling. • Worked on live production systems, diagnosing and fixing performance issues, bugs, and edge cases. • Implemented Redis-based caching and session management to improve performance and optimize database. • Built backend systems using both microservices and monolithic architectures, ensuring maintainability and scalability. • Designed and developed hundreds of scalable REST APIs using Node.js and TypeScript for production-grade applications.WWWW…