Java Backend Developer

We are looking for a Java Backend Developer to join a production\-critical backend platform within the payments domain. The role focuses on building and maintaining high\-performance backend services in a regulated, high\-scale environment, supporting transaction processing, settlements, financial reporting, and integrations with internal and external systems. Strong hands\-on Java experience and comfort working with mature, mission\-critical systems are essential.

• Design and develop backend services using Java 17+
  


• Build scalable components supporting transaction data, settlements, and reporting
  


• Integrate backend services with relational databases and internal financial systems
  


• Develop secure REST APIs aligned with compliance and security standards
  


• Collaborate closely with product owners, analysts, architects, and QA teams
  


• Optimise system performance, reliability, and data processing efficiency
  


• Participate in code reviews, testing, and continuous improvement activities
  


• Support platform modernisation and resolve production issues
  


• Contribute to clean code practices and long\-term platform scalability
  

Requirements

• 3–5 years of commercial Java backend experience
  


• Strong knowledge of Java 17+ and modern backend frameworks
  


• Hands\-on experience with relational databases (SQL; Oracle / PL/SQL preferred)
  


• Experience working with microservices and distributed systems
  


• Solid understanding of REST API design and system integrations
  


• Experience working in Agile delivery teams
  


• Good communication skills and ability to work in international environments
  
  Nice to have
  
  


• Experience in fintech, payments, banking, or other regulated domains
  


• Exposure to CI/CD pipelines, DevOps practices, or containerised environments
  


• Experience with messaging or event\-driven architectures
  


• Background in high\-volume or real\-time systems
  

Benefits

• Solid, competitive salary
  


• Work in a multinational environment on international projects
  


• Comprehensive healthcare
  


• Long\-term B2B contract with a stable project pipeline
  


• Hybrid working model (remote with 1 day per week in the Warsaw office)