Java Developer

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 Expertise (2-4Years Experience Focus) ● Core Java & Frameworks: 2-4 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