Java Spring Boot Developer

About the Role We are looking for a skilled Java Developer with 6+ years of experience to design, develop, and maintain enterprise-grade microservices and event-driven applications. You will bring strong expertise in Java, Spring Boot, and Apache Kafka - building scalable, resilient backend services deployed on Azure (preferred) or AWS cloud platforms. You will work closely with architects, product owners, and cross-functional engineering teams to deliver high-quality, cloud-native solutions that leverage modern messaging, API, and search capabilities at enterprise scale. Key Responsibilities Java & Spring Boot Development Design, develop, test, and maintain scalable Java microservices using Spring Boot - applying clean architecture, SOLID principles, and well-established design patterns for production-grade, maintainable codebases. Build and expose secure, well-documented RESTful APIs - following API-first design principles, OpenAPI / Swagger documentation standards, versioning strategies, and performance best practices. Develop and optimise data access layers using Spring Data JPA / Hibernate - managing complex entity relationships, query optimisation, and database migration strategies across relational and NoSQL databases. Write comprehensive unit and integration tests using JUnit and Mockito - maintaining high code coverage and regression confidence through test-driven development practices. Participate actively in code reviews - providing constructive technical feedback and upholding coding standards, security practices, and architectural consistency across the team. Apache Kafka & Event-Driven Architecture Design and implement event-driven microservices using Apache Kafka - developing producers, consumers, and Kafka Streams applications with Spring Kafka for reliable, scalable messaging at enterprise scale. Design Kafka topic architecture - defining partitioning strategies, replication factors, retention policies, and consumer group configurations aligned to throughput, ordering, and fault-tolerance requirements. Implement robust error handling patterns - Dead Letter Queues (DLQ), retry strategies, and poison pill handling - ensuring resilient, recoverable Kafka consumer behaviour in production. Configure Kafka Schema Registry with Avro or Protobuf - enforcing schema evolution governance and backward / forward compatibility across event-driven service boundaries. Implement exactly-once semantics and delivery guarantee patterns where business requirements demand strong consistency across distributed event streams. Monitor and troubleshoot Kafka cluster health - consumer lag, partition rebalancing, broker performance, and throughput metrics - using Kafka UI, Confluent Control Centre, or equivalent monitoring tools. Azure Cloud (Preferred) Design and deploy cloud-native Java microservices on Azure - leveraging AKS, App Services, Azure Functions, and Azure Container Registry for scalable, managed application hosting. Integrate applications with Azure messaging services - Azure Service Bus, Event Hub, and Event Grid - alongside Kafka for hybrid event-driven architectures where applicable. Implement Azure security best practices - Managed Identities, Azure Key Vault, Azure AD RBAC, and Private Endpoints - ensuring secure, least-privilege access across all application and infrastructure components. Configure Azure monitoring and observability - Application Insights, Azure Monitor, and Log Analytics - providing comprehensive production visibility and enabling rapid incident detection and resolution. Build and maintain CI/CD pipelines using Azure DevOps - automating build, test, security scanning, and deployment workflows across Dev, Test, and Production environments on Azure. Manage Azure database services - Azure SQL, Cosmos DB, and Azure Database for PostgreSQL - designing efficient data access patterns and optimising query performance for microservices workloads. OpenSearch Integration (Good to Have) Design and implement OpenSearch index mappings and search queries - building full-text search, faceted filtering, and relevance-tuned search experiences integrated with Spring Boot microservices. Develop OpenSearch aggregation pipelines for analytics, reporting, and real-time data summarisation use cases within the application platform. Integrate Spring Boot services with OpenSearch using Spring Data OpenSearch / Elasticsearch - managing index lifecycle, query DSL, and search result mapping. Optimise OpenSearch search performance - analysers, tokenisers, query caching, and shard management - for low-latency, high-relevance search at scale. Architecture & Delivery Contribute to microservices architecture design - applying DDD, CQRS, Event Sourcing, and Saga patterns to deliver loosely coupled, independently deployable services. Collaborate with Solution Architects, Business Analysts, Product Owners, and DevOps teams - translating complex requirements into well-architected, cloud-native technical solutions in Agile sprints. Troubleshoot and resolve complex production issues - performance bottlenecks, Kafka consumer lag, cloud service failures, and distributed system failures - under production pressure. Produce clear and concise technical documentation - API contracts, event schemas, architecture decision records, and deployment runbooks. Mentor and support junior Java developers - sharing knowledge across Spring Boot, Kafka, and Azure domains. What We're Looking For 6+ years of hands-on Java development experience with a strong track record of delivering enterprise microservices in production environments. Deep expertise in Spring Boot - Spring MVC, Spring Cloud, Spring Security, and Spring Kafka - with strong understanding of microservices design patterns. Proven Apache Kafka experience - producer / consumer development, Kafka Streams, topic design, error handling, and Schema Registry in production event-driven systems. Strong Azure cloud experience (preferred) - AKS, App Services, Service Bus, Event Hub, Key Vault, Azure AD, Application Insights, and Azure DevOps. Working knowledge of AWS cloud services - EC2, EKS, SQS, SNS, MSK, IAM - as an alternative or complementary cloud platform. Solid database skills - relational (Azure SQL / PostgreSQL / MySQL) and non-relational (Cosmos DB / MongoDB / Redis) - with strong SQL and ORM expertise. Experience with containerisation (Docker) and orchestration (Kubernetes / AKS / EKS) for cloud-native microservices deployment. Hands-on CI/CD experience - Azure DevOps, Jenkins, or GitLab CI - for automated build, test, and deployment pipelines. Strong understanding of event-driven architecture - messaging patterns, eventual consistency, saga orchestration, and distributed system design. Excellent communication and collaboration skills - able to engage effectively with architects, product owners, and cross-functional engineering teams. Nice to Have Hands-on OpenSearch / Elasticsearch experience - index design, full-text search, aggregations, and Spring Boot integration. Experience with Azure Managed Kafka (Event Hub for Kafka) or AWS MSK for fully managed Kafka deployment. Familiarity with service mesh technologies - Istio or Linkerd - for AKS microservices traffic management and observability. Knowledge of CQRS and Event Sourcing patterns using Axon Framework or equivalent. Exposure to GraphQL API development alongside REST. Experience with Infrastructure-as-Code - Terraform or Azure Bicep - for cloud resource provisioning. Azure Developer Associate (AZ-204) or Azure Solutions Architect (AZ-305) certification. AWS Certified Developer Associate certification. Experience in Financial Services, FinTech, Retail, or other regulated industry environments.