Associate - Application Developer

The Opportunity We are looking for a Java Full Stack Developer to design, build, and scale mission-critical digital payment applications powering UPI Global platforms. This role offers the opportunity to work on real-time, high-volume, secure financial systems that operate at national scale, directly impacting millions of users across India. You will work end-to-end on modern full-stack architectures, collaborating closely with product, QA, and platform teams. Job Details Role: Java Full Stack Application Engineer Department: Product - Technology Experience: 2 to 6 Years

Employment Type: Full-time | Permanent

Education: BE / BTech or equivalent professional qualification Location: Mumbai Work Mode: 5 Days Work From Office (WFO)

Key

Responsibilities Design and develop scalable RESTful APIs using Java, Spring Boot, and Hibernate/JPA for UPI Global applications Build and maintain microservices-based architectures, integrating with internal and external payment systems Develop responsive, high-performance frontend applications using React.js, Redux, and JavaScript / TypeScript Ensure seamless frontend-backend integration for real-time payment workflows Work with event-driven systems (Kafka) for asynchronous transaction processing Implement secure authentication and authorization using OAuth2, JWT, and industry best practices Optimize applications for performance, scalability, reliability, and security Write unit and integration tests, and participate in code reviews to maintain engineering standards Actively participate in Agile ceremonies and collaborate with cross-functional teams

Requirements Key Skills &

Experience Required Strong expertise in Java 8+ and above, including core programming constructs such as streams, collections, multithreading, concurrency, and functional programming, along with a working understanding of JVM internals such as memory model, garbage collection, and class loading Hands-on experience with Spring Boot and backend frameworks, including dependency injection, REST API development, exception handling, and microservices-based application design Solid understanding of modern frontend development, with React.js, Redux, and TypeScript, including component architecture, hooks, state management, and efficient API integration patterns Familiarity with Node.js-based middleware concepts, including event loop behavior, non-blocking I/O, and lightweight service orchestration Experience working with microservices and distributed systems, including REST API principles such as idempotency, API versioning, request validation, and error modeling Strong knowledge of event-driven architecture and messaging systems like Kafka, including topics, partitions, consumer groups, and asynchronous processing patterns Experience with SQL and NoSQL databases, including relational modeling, transactions, indexing, as well as NoSQL data modeling for scalability and performance Understanding of caching strategies using Redis or similar systems, including cache-aside patterns, TTL, and eviction policies Knowledge of authentication and security mechanisms, including OAuth2, JWT, secure API handling, and input validation Good understanding of system design principles, including SOLID principles, layered architecture, and commonly used design patterns such as Factory, Strategy, and Proxy Exposure to DevOps practices, including version control (Git), build tools (Maven/Gradle), and environment-based configuration management Awareness of observability practices, including structured logging, metrics monitoring, and debugging production issues Strong problem-solving, analytical, and communication skills, with the ability to work independently and in cross-functional Agile teams Good to Have Skills and Experience Experience deploying applications on cloud platforms such as AWS, Azure, or GCP Exposure to CI/CD pipelines using Jenkins, GitLab CI, or GitHub Actions Knowledge of containerization and orchestration using Docker and Kubernetes Familiarity with high-availability, low-latency systems, particularly in financial or payment processing domains