Java Backend Developer /UPI & BBPS

Job Summary

We are looking for a Java Backend Developer with 3 to 5 years of experience in developing scalable and secure backend applications for UPI, PPI and BBPS payment platforms.

The candidate must have hands-on production experience working on at least one live UPI application/UPI app. Strong experience in Core Java, Spring Boot, REST APIs, Microservices, SQL and third-party API integrations is required.

Key Responsibilities

• Develop backend services using Core Java and Spring Boot.
• Design and develop REST APIs and Microservices for UPI and BBPS applications.
• Develop and maintain backend APIs for live UPI applications.
• Implement UPI transaction flows including payment initiation, validation, success/failure/pending status, status enquiry, reversal, refund and callbacks/webhooks.
• Implement retry, timeout, exception handling and duplicate transaction prevention.
• Develop BBPS APIs for bill fetch, bill payment, transaction status, validation and reconciliation.
• Integrate with banks, PSPs, payment gateways, BBPS systems, billers and third-party APIs.
• Implement idempotency, transaction validation, business rules, audit logging and reconciliation.
• Work with MySQL, PostgreSQL or Oracle and write optimized SQL queries.
• Troubleshoot production issues and perform RCA.
• Implement API security, logging, monitoring and secure data handling.
• Participate in code reviews, testing, performance optimization and production releases.

Mandatory Skills

• Core Java / Java 8+
• Spring Boot / Spring MVC
• REST API development
• Microservices
• Hibernate / JPA
• SQL MySQL / PostgreSQL / Oracle
• Git
• Maven / Gradle
• JUnit / Mockito
• Postman
• Third-party API integration
• Exception handling and logging

Mandatory Payment Domain Experience

• Hands-on experience with at least one live UPI application/UPI app
• Strong understanding of UPI transaction lifecycle
• Payment API and financial system integrations
• Transaction status, reversal, refund and retry handling
• Timeout and duplicate transaction handling
• Idempotency
• Reconciliation
• Production issue troubleshooting
• Banking / FinTech / Digital Payments experience

Good to Have

• BBPS
• PPI / Digital Wallet
• Kafka / RabbitMQ
• Redis
• Docker / Kubernetes
• AWS / Cloud
• CI/CD
• Prometheus / Grafana / ELK
• High-volume transaction processing

Contract Details

• 6-month Contract-to-Hire position
• Onsite work in Chennai
• Contract may be extended or converted to a permanent position based on project requirements and performance
• Candidates must be willing to work onsite in Chennai