Senior Java Backend Developer – Microservices | ₹5 LPA To ₹8 LPA

Winzons; India; On-site; INR 3,500,000 - 6,500,000; Full time

Job summary

I2B Technologies is seeking a Senior Java Backend Developer to anchor the core platform in Hyderabad. You will architect, implement, and optimize scalable backend services using Java, Spring Boot, and modern distributed patterns to support millions of users and high data velocity.

The role emphasizes cloud-agnostic design, microservices, real-time communication, and high-performance data processing, with a focus on reliability, low latency, and robust testing across the stack.

Qualifications

• Bachelor's or Master's degree in Computer Science or related field.
• Deep Java/backend expertise with Spring Boot or similar frameworks.
• Experience designing distributed microservices and scalable backend systems.
• Strong knowledge of concurrency, JVM optimization, and performance tuning.
• Experience with Kafka or RabbitMQ and NoSQL stores like Cassandra/ScyllaDB/Aerospike.

Responsibilities

• Design, develop, and maintain high-performance backend services and APIs in Java.
• Drive microservices implementation with clear contracts and inter-service communication.
• Build real-time, low-latency data channels (WebSockets/MQTT) for millions of clients.
• Optimize data models and storage with NoSQL/SQL databases and caching layers.
• Implement scalable, resilient systems with monitoring and observability.

Skills

Core Java

Spring Boot

Quarkus/Micronaut

Distributed Systems

Concurrency & Performance

Messaging & Eventing

NoSQL Databases

SQL Databases

Testing & Quality

Education

Bachelor's or Master's in CS or related

Job description

Company Name: I2B Technologies

Job Role: Senior Java Backend Developer

Work Type: Full-Time

Experience: 4-7 Years (Core Backend Expertise)

Qualification: Bachelor's or Master's Degree in Computer Science or Related Field

Location: Hyderabad, India (Hybrid/Remote depending on project)

Role Overview :

We are seeking an exceptionally skilled and driven Senior Java Backend Developer to anchor the core platform. This role is critical to architecting and delivering a hyper-scalable, low-latency, and distributed system capable of supporting millions of concurrent users and high-velocity data flow.

You will take extreme ownership of mission-critical services, aiming to set a new standard. This platform must be designed for cloud-agnostic deployment from day one.

Key Responsibilities :

• Architecture & Design : Design, develop, and maintain high-performance, resilient, and fault-tolerant backend services and APIs using Java and Spring Boot/Quarkus.
• Microservices Implementation : Drive the decomposition and development of services within a microservices architecture, focusing on clear contract definition, service mesh integration, and inter-service communication patterns (e.g., gRPC, REST).
• Real-Time & Low Latency : Implement and optimize real-time, bi-directional communication channels (e.g., WebSockets, MQTT) for instantaneous data synchronization and persistent connection management for millions of mobile clients.
• Database & Data Flow : Design and optimize data models and persistence layers, integrating with high-volume, low-latency databases like Cassandra, ScyllaDB, or Aerospike for primary data storage, and ensuring efficient caching and read/write performance.
• Scalability & Resilience : Implement advanced techniques for horizontal scaling, distributed transactions, circuit breakers, and load balancing to ensure 99.99% uptime and operational resilience.
• Ability to perform Research / POCs & choose the suitable technology.

Required Technical Expertise (4- 5 Years Experience Focus) :

• Core Java & Frameworks : 4- 5 years of hands-on experience in Java, with deep, production-grade expertise in Spring Boot (or equivalent, e.g., Quarkus/Micronaut) for building RESTful and event-driven services.
• Distributed Systems : Proven experience designing and implementing scalable services within a distributed system/microservices architecture, including experience with service discovery and configuration management.
• Concurrency & Performance : Mastery of Java concurrency primitives and advanced performance tuning (JVM optimization, garbage collection tuning, thread pool management) to achieve sub-100ms P95 latency.
• Messaging & Eventing : Expert knowledge of and hands-on experience with high-throughput message brokers like Apache Kafka or RabbitMQ for handling high-velocity data, notifications, and background processing.
• Database Expertise : Deep practical experience with at least one NoSQL distributed database (e.g., Cassandra, ScyllaDB, or Aerospike) and strong SQL proficiency (e.g., MySQL, Postgres), including complex query optimization and schema evolution.
• Testing & Quality : Proven ability to write high-quality, well-tested code, utilizing frameworks like JUnit, Mockito, and focusing on unit, integration, and performance testing.

Scalability & Performance Expectations :

• User Volume : Successfully design and scale the application backend to handle millions of concurrent, persistent mobile connections.
• Latency Goal : Services must be tuned for P95 latency of less than 100 milliseconds for critical operations like data sync and status updates.
• Cloud-Agnostic Design : Demonstrate experience designing applications for a truly cloud-agnostic environment, utilizing containerization (Docker, Kubernetes) and abstracting infrastructure dependencies to allow seamless migration between AWS, GCP, or Azure.
• Monitoring & Observability : Strong experience implementing and utilizing a robust observability stack (e.g., Prometheus/Grafana, ELK/Loki, distributed tracing like Jaeger/Zipkin) to profile performance and rapidly diagnose production issues.

Startup Mindset & Delivery Goals :

• Extreme Ownership : Ability to own a feature end-to-end, from architectural design and coding to deployment and post-launch monitoring, taking full responsibility for its success and reliability.
• Collaboration & Iteration : Thrive in a fast-paced, iterative environment, collaborating closely with mobile developers, product managers, and cloud engineers.
• Impact Focus : A strong bias for action, prioritizing work that directly impacts product