Developed and enhanced a service for a travel platform, integrating the user interface with external systems while supporting real-time data processing and location-based searches. Improved search performance by 40% using Redis and Elasticsearch with geospatial indexing for faster location queries. Leveraged Kafka for real-time customer comment processing, and built DAO with JDBC Template for efficient interaction with MySQL databases. Implemented Redis cache for high performance in handling large-scale queries, and deployed the system on AWS for scalable infrastructure. Collaborated with business analysts to translate requirements into effective technical solutions, ensuring alignment with business goals.

Developed and maintained the Backend System API that connects the user interface to telecom services such as billing, data, SMS, and calls, enabling dynamic management of customer packages and promotional offers. Designed a flexible promotion policy engine to apply marketing-driven adjustments, such as multiplying data, SMS, or call minutes. Built RESTful APIs using Spring Boot and integrated with the Billing System to ensure accurate reflection of promotions on invoices. Leveraged Spring Data JPA, Hibernate, and MySQL for package management, and used JWT for secure authentication. Utilized Docker for containerization and performed unit testing with JUnit to ensure reliable deployment and promotion accuracy.

Developed a web-based application for customer registration, mobile number allocation, and online account charging. Automated mobile number assignment for new customers and integrated payment gateways for seamless recharge transactions. Built a notification service for sending real-time SMS and email alerts on successful transactions and low balance updates. Created RESTful APIs using Java, Spring Boot, and Hibernate to manage customer accounts and transaction histories, and designed the MySQL database schema to store customer data, payment history, and notification logs. Integrated third-party SMS and email services to enhance customer communication.

Contributed to the migration from SOAP to RESTful API architecture, improving system scalability and response times. Led the migration of the Subscription Service to AWS, enhancing reliability and scalability while developing key features like plan management, activation, and cancellation, reducing customer support queries. Designed and implemented the Notification Service for real-time alerts and optimized message processing, and helped enhance the Charging Service by integrating a payment gateway, improving transaction success rates. Collaborated with cross-functional teams to deliver cohesive solutions.

Developed a robust Library Management System that enables university staff and students to manage book inventory, borrowing, and returns. Utilized Thymeleaf for the frontend and Spring Boot for the backend with a MySQL database. Implemented RESTful APIs for core functionalities like book management and user accounts, ensuring secure access with Spring Security.