Java developer for mainframe systems

Our mission as an IT services company is to deliver the best solutions to our clients around the world. We achieve this by analyzing our clients' needs and matching them with the skills and aspirations of our employees. That is why one of our main motivations is to ensure a satisfying experience for every Employee and Consultant. Joining us means becoming part of a community of diverse personalities. Start your journey with act digital!

• Designing and developing REST APIs using Java and Spring Boot.
• Creating APIs using a contract-first approach with OpenAPI/Swagger.
• Developing integration and transport services connecting digital solutions with mainframe systems via IBM MQ.
• Mapping and validating data, handling errors, and ensuring reliable message exchange.
• Supporting deployments on PaaS platforms and in containerized environments.
• Participating in a potential migration from a single-cluster to a multi-cluster architecture.
• Mentoring and training other developers.
• Preparing an orderly handover of solutions and technical knowledge.

• At least 5 years of software development experience.
• Very good knowledge of Java and Spring Boot, supported by practical experience.
• Experience designing and implementing REST APIs.
• Practical knowledge of OpenAPI/Swagger and API contracts.
• Experience working with IBM MQ or similar communication technologies.
• Knowledge of integration patterns and asynchronous communication.
• Experience in containerized environments and/or on PaaS platforms.
• Ability and willingness to mentor and train developers and share knowledge.
• Fluent spoken and written English, essential for daily collaboration with the team in Denmark.
• Будет плюсом: Knowledge of COBOL and practical experience developing mainframe systems; Experience integrating Java applications with COBOL/mainframe systems; Experience in the banking or payments sector

• Contract: B2B.
• Rate: up to PLN 190/hour net + VAT.
• Project start: December 2026.
• Access to local and international projects - clients from France, Germany, Portugal, the United Kingdom, and the Benelux countries.
• Support for professional development - training, technical certifications, participation in conferences, foreign language lessons, and soft skills training co-financed up to PLN 2,000.
• Flexibility - you choose the form of cooperation: an employment contract or a business-to-business contract.
• Referral bonus for recommending candidates of up to PLN 6,000.
• Fully paid Medicover card.
• Multisport card.
• Regular team events and gifts.
• Mobility Program.
• Long-term cooperation.