Senior Java Developer

We are looking for Senior Java Developers to join a long-term payments technology programme supporting a large-scale terminal management platform. The role focuses on backend development, enterprise integrations, system modernisation, and the gradual transformation of a business-critical platform managing hundreds of thousands of payment terminals.

This is a hands-on engineering position requiring strong Java expertise, experience with distributed systems, and the ability to work independently within a complex enterprise environment that combines modern technologies with legacy components.

Responsibilities

• Design and implement IT solutions based on analytical and technical documentation

• Review analytical documentation and translate it into technical implementation

• Create and maintain technical documentation

• Support technical upgrade and modernisation of the existing system

• Work with legacy code and contribute to gradual system migration

• Conduct regular application scans and remove vulnerabilities

• Build and maintain integrations with internal and external systems

• Work with distributed transactions, queues, caching, and database integrations

Requirements

• Very good knowledge of Java 8+ and object oriented programming

• Practical experience with Spring, Spring Boot, Hibernate/JPA, and JEE

• Experience designing, implementing, documenting, and testing application components independently

• Practical knowledge of RabbitMQ or other message queue systems

• Good knowledge of Maven, Git, GitLab, GitLab CI/CD, Jenkins, Nexus, Jira

• Knowledge of relational databases, especially Oracle

• Practical experience with REST API design

• Experience with system integrations and distributed systems

• Experience with application servers such as JBoss / WildFly

• Knowledge of scanning tools such as Fortify or Sonatype

• English B2
• Fluent Polish
• Full availability in the Polish time zone

• Ability to work 5 days per week from the Warsaw office

Nice to have

• Experience in payments, acquiring, terminal management, or financial services

• Experience with SOAP, RMI, database links, or direct database integrations

• Experience with Hazelcast or distributed caching

• Experience with distributed transaction patterns such as two phase commit or Saga

• Experience working with legacy systems and migration programmes

• Experience with GWT / GWTExt

Benefits

• Solid, competitive salary

• Work in a multinational environment on international projects

• Comprehensive healthcare

• Long-term B2B contract with a stable project pipeline