Senior Java Developer – API Design

CoreData Systems

Freelance · Remote · Flexible hours

About the role

CoreData Systems is revamping the performance and reliability of its customer‑facing services. We need a seasoned Java Developer to lead the redesign of critical backend components, ensuring low latency and high availability under load.

Key responsibilities

• Refactor existing services for optimal throughput using Java 17+
• Implement resilient microservice patterns with Spring Boot
• Introduce comprehensive monitoring, tracing, and automated recovery mechanisms
• Collaborate with QA and DevOps to embed performance tests in CI pipelines
• Document architectural decisions and create migration guides

Must-have skills

• 5+ years of Java development experience
• Deep expertise in Spring Boot and microservice architecture
• Proven track record of performance tuning and reliability engineering
• Familiarity with Docker, Kubernetes, and observability tools

Nice to have

• Experience with reactive programming (Project Reactor, RxJava)
• Knowledge of cloud platforms (AWS, GCP)
• Background in CI/CD automation for Java services