Senior Java Developer with Apache Kafka (f/m/x)

Sii is hiring a Senior Java Developer to build a modern enterprise data integration and processing platform supporting global logistics and transportation processes.

• Minimum 10 years of commercial software development experience including senior-level expertise in Java backend development
• Strong hands-on production experience with Apache Kafka
• Proven experience designing and building microservices, scalable backend services, and event-driven architectures
• Practical experience with distributed systems, enterprise integrations, and data processing solutions
• Ability to contribute independently to technical design and solution architecture discussions
• Very good English communication skills for international collaboration
• Residence in Poland
• Valid Confluent Certified Developer for Apache Kafka (CCDAK) certification

Nice to have:

• Production experience with Kafka Streams and Kafka Connect
• Experience with cloud-native and containerized environments including Azure, Kubernetes, OpenShift, Docker, or Podman

• Designing, developing, and maintaining scalable backend services and microservices using Java and Spring Boot
• Implementing event-driven architectures and data-processing solutions based on Apache Kafka
• Building enterprise integrations between internal and external systems using APIs, messaging platforms, and asynchronous communication
• Participating in technical design and solution architecture discussions on distributed systems and integration patterns
• Supporting modernization and transformation of legacy applications into scalable, cloud-ready solutions
• Monitoring, troubleshooting, and optimizing application performance, reliability, and scalability in distributed environments
• Collaborating with developers, architects, and business stakeholders on data integration and digital transformation initiatives

The candidate must have residence in Poland and hold a valid Confluent Certified Developer for Apache Kafka (CCDAK) certification.