Senior Java Developer

Senior Java Developer 📍 Location: Kraków, Poland (hybrid: 2 days in the office, 3 days remote) 📄 B2B Contract: 190 – 230 PLN / hour We are looking for a proactive Senior Java Developer to join an international Agile team building high‑performance backend solutions for trading and risk‑related systems. You will work closely with engineers and analysts to design, develop and optimize services supporting critical business processes. This role offers the opportunity to work on low‑latency, high‑throughput applications and influence architecture, engineering standards and delivery quality across a complex technology landscape. What We Offer: Long‑term cooperation within an international engineering environment. Real influence on architecture, engineering standards and delivery quality. Work in a multicultural, distributed setup. Private medical care (LuxMed) and Multisport card. Hybrid model: 2 days per week in the Kraków office.
Requirements:
5+ years of experience in Java backend development (Java 11+). Strong knowledge of REST, HTTPS, microservices and messaging (MQ). Experience with SQL and at least one mainstream database (Postgres, Sybase or similar). Experience owning or leading delivery of Java‑based modules or services. Strong analytical and problem‑solving skills. Very good communication skills in English. Ability to work in a dynamic environment and handle pressure. Curiosity, proactiveness and continuous learning mindset. Nice to Have: Experience in production environments. Experience with Agile development and CI/CD. Domain knowledge in financial systems: trade lifecycle, post‑trade, FX.
Must have: Java, REST API, Microservices, IBM MQ, SQL, PostgreSQL, Sybase, Communication skills
Nice to have: CI/CD, Agile
Daily tasks: - Design and develop backend services and microservices in Java.
– Build and maintain RESTful APIs and distributed system components.
– Develop high‑availability, high‑performance solutions supporting trading workflows.
– Integrate with internal platforms and support end‑to‑end transaction lifecycle.
– Optimize system performance, stability and scalability.
– Collaborate with global engineering and business teams.
– Participate in Agile ceremonies: sprint planning, reviews, retrospectives and daily stand‑ups.