Java Developer | UPI & BBPS Backend

ThreatXIntel; Chennai District; On-site; INR 800,000 - 1,200,000; Full time

Job summary

ThreatXIntel is seeking a strong Java Backend Developer with 3 to 5 years of experience to build scalable and secure backend services. You will work on UPI and BBPS applications, developing Core Java and Spring Boot APIs, and integrating with banks, PSPs, and third-party gateways.

You will design and implement RESTful microservices, ensure data integrity with SQL databases, handle transaction flows, and contribute to production readiness, monitoring, and troubleshooting of live payments systems.

Qualifications

• Hands-on experience with at least one live UPI application/UPI app.
• Strong knowledge of Core Java, Spring Boot, REST APIs, and Microservices.
• Experience with SQL databases and data modeling for transactional systems.
• Experience integrating with banks, PSPs, payment gateways, and third-party APIs.

Responsibilities

• Develop and maintain backend services using Core Java and Spring Boot.
• Build and maintain REST APIs and Microservices for UPI and BBPS applications.
• Develop backend APIs for live UPI applications and handle transaction flows.
• Implement transaction management, idempotency, and retry mechanisms.
• Integrate with banks, PSPs, payment gateways, BBPS systems, and billers.

Skills

Core Java

Java 8+

Spring Boot

REST APIs

Microservices

SQL

Hibernate/JPA

Git

Maven/Gradle

JUnit/Mockito

Postman/API troubleshooting

Third-party API integrations

Tools

MySQL

PostgreSQL

Oracle

Job description

We are looking for a strong Java Backend Developer with 3 to 5 years of experience in developing scalable, secure, and high-performance backend applications.

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

The role involves developing and maintaining backend APIs for UPI and BBPS applications, including payment processing, transaction management, financial integrations, validations, reconciliation, and production support.

Key Responsibilities

• Develop and maintain backend services using Core Java and Spring Boot.
• Build and maintain REST APIs and Microservices for UPI and BBPS applications.
• Develop backend APIs for live UPI applications.
• Implement UPI transaction flows including:
• Payment initiation
• Transaction validation
• Success / Failed / Pending handling
• Transaction status enquiry
• Reversal and refund
• Callback / webhook processing
• Retry and exception handling
• 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 transaction management, idempotency, duplicate prevention, timeout and retry mechanisms.
• Develop business validations, transaction rules, audit logs, and reconciliation processes.
• Work with MySQL, PostgreSQL, or Oracle and write optimized SQL queries.
• Troubleshoot production issues, perform RCA, and implement permanent fixes.
• Ensure API security, logging, monitoring, auditability, and data protection.
• Participate in code reviews, unit/integration testing, performance optimization, and production releases.

Mandatory Technical Skills

• Strong Core Java
• Java 8+
• Spring Boot / Spring MVC
• RESTful API development
• Microservices architecture
• Hibernate / JPA
• SQL and relational databases
• Exception handling and logging
• Git
• Maven / Gradle
• JUnit / Mockito
• Postman / API troubleshooting
• Third-party API integrations

Mandatory Domain Experience

• Hands-on experience with at least one live UPI application/UPI app
• Understanding of the UPI transaction lifecycle
• Experience with payment APIs and financial integrations
• Understanding of transaction states, reversals, refunds, retries, and reconciliation
• BBPS experience preferred
• Banking / FinTech / digital payments experience preferred

Good to Have

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

Ideal Candidate

The ideal candidate should be a strong Java Backend Engineer with hands-on UPI application experience, capable of independently developing APIs, implementing payment transaction logic, integrating external financial systems, and troubleshooting production payment issues.

Key Requirement: Strong Java expertise + hands-on live UPI application experience is mandatory. BBPS / FinTech / Banking experience is preferred.