Senior Java Developer - Immediate joiners only & F2F interview is Mandatory

Wissen Technology; Mumbai; On-site; INR 2,400,000 - 3,600,000; Full time

Job summary

Wissen Technology in Mumbai focuses on building scalable backend services using Java/J2EE, Spring Boot, and microservices. The role emphasizes translating business requirements into robust system designs and delivering cloud-native solutions in an Agile environment.

You will own high-level and low-level designs, guide API contracts, and drive performance, security, and reliability across distributed systems. Strong leadership and hands-on coding are expected.

Qualifications

• 10–15 years of hands-on Java/J2EE backend development experience.
• Strong expertise in Core Java, JVM, multithreading and performance tuning.
• Proficiency in Spring Boot, REST APIs and microservices design.

Responsibilities

• Design, develop, and maintain enterprise-scale backend applications using Java/ Spring Boot and microservices.
• Translate requirements into technical designs including data models and API contracts.
• Lead architecture discussions, reviews, and proof-of-concept evaluations.
• Build scalable, distributed systems with proper patterns for caching, retries, and resilience.
• Develop secure RESTful APIs with versioning and access controls.
• Design relational schemas, queries, and data-access layers.
• Create event-driven services using Kafka/RabbitMQ/JMS/IBM MQ.
• Write unit/integration tests with JUnit/Mockito; promote TDD where applicable.
• Optimize performance, concurrency, and latency; monitor and debug production issues.
• Containerize with Docker; deploy via Kubernetes and CI/CD pipelines.
• Implement observability with logs, metrics, traces, dashboards, and alerts.
• Mentor juniors; conduct code reviews and enforce engineering standards.

Tools

Docker

Kubernetes

Kafka

Jenkins

Maven/Gradle

Git

JUnit/Mockito

Job description

We are looking for a Java Backend Developer to design, build, and operate scalable, secure, and high-performance backend services. The ideal candidate will own technical design for complex features, translate business requirements into robust system designs, and deliver cloud-native microservices in an Agile environment.

Key Responsibilities

• Design, develop, and maintain enterprise-scale backend applications using Java/J2EE, Spring Boot, REST APIs, and microservices.
• Translate business requirements into clear technical designs, including service boundaries, data models, API contracts, integration flows, and deployment architecture.
• Lead or contribute to HLD and LLD, architecture discussions, technical design reviews, and proof-of-concept evaluations.
• Build scalable, resilient, and distributed systems using appropriate patterns for caching, asynchronous processing, idempotency, retries, circuit breaking, and graceful degradation.
• Develop secure and well-documented RESTful APIs, applying API versioning, authentication, authorization, rate limiting, and secure coding practices.
• Design and optimize relational database schemas, queries, indexes, transactions, and data-access layers using SQL-based databases.
• Build event-driven services using messaging platforms such as Kafka, RabbitMQ, JMS, or IBM MQ.
• Implement automated unit, integration, and end-to-end tests using JUnit, Mockito, Test containers, or similar frameworks; promote TDD where applicable.
• Optimize application performance, concurrency, memory usage, database interactions, and service latency.
• Containerize services using Docker and support deployment through Kubernetes and CI/CD pipelines.
• Implement observability through structured logging, metrics, tracing, dashboards, and alerting.
• Troubleshoot production issues, perform root-cause analysis, and drive permanent fixes and preventive improvements.
• Conduct code reviews, enforce engineering standards, and mentor junior developers on design, coding, and testing practices.

Required Skills

• 10–15 years of hands-on experience in Java/J2EE backend development.
• Strong expertise in Core Java, Java 11/17+, collections, multithreading, concurrency, JVM fundamentals, and exception handling.
• Proficiency in Spring Boot, Spring MVC, Spring Data JPA, Spring Security, and RESTful API development.
• Strong experience in microservices architecture, distributed systems, and system design.
• Solid understanding of SOLID principles, design patterns, DRY, clean code, and domain-driven design (DDD).
• Experience designing APIs, data models, service integrations, and scalable technical solutions.
• Hands-on experience with SQL databases such as PostgreSQL, Oracle, MySQL, or SQL Server.
• Experience with Kafka or another event-streaming/messaging platform.
• Experience with Git, Maven/Gradle, JUnit, Mockito, Docker, and CI/CD tools such as Jenkins, GitHub Actions, GitLab CI, or Azure DevOps.
• Strong debugging, performance-tuning, and production-support skills.