Full Stack Java Developer

For our Client we are looking for a Full Stack Java Developer. Warsaw, hybrid (4 days per week from the office) B2B: 28,000–32,000 PLN per month Your responsibilities Gather and analyse requirements with business stakeholders Design, plan, implement and test changes with the engineering team Adapt and enhance legacy Java applications for ISO 20022 changes Develop and maintain backend services and integrations Participate in code reviews, UAT support and production releases Continuously improve code quality and system design Requirements: 4+ years of experience as a Java / Full Stack Developer Strong hands-on experience with: Java, Spring, Spring Boot (DI, Spring Data, Spring Security) Hibernate, DB2 Apache Kafka (producers, consumers, Kafka Streams, Kafka Connect) MongoDB (document modelling, Spring Data MongoDB) RESTful APIs, microservices, event‑driven architectures Maven (multi-module builds) Docker Git & CI/CD (GitLab CI preferred) Experience working in distributed systems and complex legacy codebases Strong analytical skills and ability to understand complex business logic Good communication skills and ability to work in a global team