Senior Java Backend Developer (Java / Spring Boot / Microservices

Overview Cogency Inc.

is seeking a highly skilled Senior Java Backend Developer to build and maintain scalable, high-performance enterprise applications.

The ideal candidate will have deep expertise in Java, Spring Boot, microservices architecture, and Kafka-based event-driven systems, with a strong focus on backend development, system design, performance optimization, and distributed systems integration.

Key Responsibilities Design, develop, and maintain robust backend services using Java and Spring Boot Build and enhance RESTful APIs and microservices-based solutions Develop and support event-driven architectures using Kafka Participate in architecture discussions and contribute to design decisions Implement resilience, fault tolerance, and scalability patterns Optimize application performance, memory usage, and database interactions Write clean, maintainable, and well-documented code Perform unit, integration testing, and support QA/UAT cycles Monitor, troubleshoot, and resolve production issues Collaborate with DevOps, frontend teams, and business stakeholders Required Technical Skills Core Java Strong understanding of Object-Oriented Programming (OOP) Expertise in Collections and Exception Handling Hands-on experience with Java 8+ (Streams, Lambdas) Knowledge of Design Patterns Understanding of JVM internals and Garbage Collection Robust knowledge of multithreading and concurrency Spring Boot & Backend Frameworks Dependency Injection (DI) and Inversion of Control (IoC) REST API development and best practices Configuration and environment management JPA / Hibernate for persistence Transaction management Unit and integration testing (JUnit, Mockito) Microservices Architecture Service decomposition and domain-driven design (DDD) Inter-service communication (REST, messaging) Resilience patterns (Circuit Breaker, Retry, Bulkhead) Observability (logging, monitoring, distributed tracing) API gateway and service discovery Kafka & Event Streaming Kafka topics, producers, and consumers Consumer groups and offset management Kafka cluster architecture and replication Message serialization (Avro / JSON) Monitoring, troubleshooting, and performance tuning Database & Performance Strong SQL skills and query optimization Experience with relational databases (Oracle, SQL Server, PostgreSQL) Knowledge of indexing and performance tuning Qualifications Bachelor’s degree in Computer Science, Engineering, or related field 7+ years of hands-on backend development experience Experience working in large-scale enterprise environments Strong analytical, problem-solving, and debugging skills Excellent communication and collaboration abilities Work Model Hybrid – 3 days per week onsite (mandatory) in downtown Calgary #J-18808-Ljbffr