Job Title: Senior Java Backend Developer (Java / Spring Boot / Microservices / Kafka) Work Location: Client 3 days onsite per week (mandatory) downtown Calgary Company: Cogency Job SummaryWe are seeking a Senior Java Backend Developer with strong expertise in building scalable, high-performance enterprise applications. The ideal candidate will have deep hands-on experience in Java, Spring Boot, microservices architecture, and Kafka-based event-driven systems. This role focuses primarily on backend development, system design, performance optimization, and integration within a distributed environment. Key ResponsibilitiesDesign, develop, and maintain robust backend services using Java and Spring BootDevelop and maintain RESTful APIs and microservices-based solutionsBuild and support event-driven architectures using KafkaParticipate in architecture discussions and contribute to technical design decisionsImplement resilience, fault tolerance, and scalability best practicesOptimize application performance, memory usage, and database interactionsWrite clean, maintainable, and well-documented code following coding standardsPerform unit testing, integration testing, and support QA/UAT cyclesMonitor, troubleshoot, and resolve production issuesCollaborate with DevOps, frontend teams, business analysts, and other stakeholders Required Technical SkillsCore JavaStrong understanding of Object-Oriented Programming (OOP) principlesIn-depth knowledge of Collections and Exception HandlingHands-on experience with Java 8 features (Streams, Lambdas)Solid understanding of Design PatternsKnowledge of Garbage Collection and JVM memory managementMultithreading and concurrency concepts Spring Boot & Backend FrameworksDependency Injection (DI) and Inversion of Control (IoC)REST API development and best practicesConfiguration management and environment handlingJPA / Hibernate for data persistenceTransaction managementUnit and integration testing (JUnit, Mockito) Microservices ArchitectureService decomposition and domain-driven design principlesInter-service communication (REST, messaging)Resilience patterns (Circuit Breaker, Retry, Bulkhead)Logging, monitoring, and distributed tracing (Observability)API gateway and service discovery concepts KafkaTopics, Producers, and Consumers implementationConsumer Groups and offset managementKafka cluster architecture and replicationMessage serialization (Avro/JSON)Kafka monitoring, troubleshooting, and performance tuning Database & PerformanceStrong SQL skills and query optimizationExperience with relational databases (e.g., Oracle, SQL Server, PostgreSQL)Understanding of indexing and performance tuning QualificationsBachelors degree in Computer Science, Engineering, or a related field7+ years of hands-on backend development experienceExperience working in large-scale enterprise environmentsStrong analytical, problem-solving, and debugging skillsExcellent communication and collaboration abilities
Job Title
Senior Java Backend Developer