At least 5 years of senior-level experience in Java backend development, including designing and maintaining distributed systems at scale, Minimum 2 years of experience in a technical leadership role, involving mentoring engineers and guiding architectural decisions, Strong understanding of high-availability, high-throughput architectures and the JVM ecosystem (Java required; Kotlin/Scala/Groovy as a plus), Ability to collaborate closely with business and product stakeholders, effectively balancing technical quality with business priorities, Very good command of English at B2/C1 level, enabling fluent communication in an international environment, Fluent Polish required, Residing in Poland required