Senior Java Engineer for Cloud Monolith Modernization

Payback PL; Warszawa; On-site; PLN 260,000 - 380,000; Full time

Job summary

Payback PL in Warsaw is seeking an accomplished backend engineer to own and evolve a large-scale Java application running in the cloud for Germany’s largest loyalty program. You’ll analyze requirements, fix production issues, and drive robust, maintainable solutions inside a complex monolith.

You will collaborate with business stakeholders and product teams, implement automated tests, document architectural decisions, and contribute to engineering best practices in an agile environment.

Qualifications

• 7+ years of professional experience in backend software development.
• At least 5 years of hands-on experience with Java in large-scale enterprise applications and complex codebases.
• Strong experience maintaining and evolving large monolithic systems in production.
• Solid knowledge of Java, Spring/Spring Boot, object-oriented design principles, and clean code practices.
• Experience working with AWS Cloud or another major cloud provider.
• Strong understanding of application architecture, performance optimization, and maintainability.
• Experience with automated testing, including unit and integration tests.
• Familiarity with CI/CD pipelines and modern software delivery practices.
• Excellent communication skills and ability to collaborate with technical and business stakeholders.
• Fluent English (B2+) spoken and written.
• Ownership mindset with a strong focus on delivering business value.
• Ability to navigate complex legacy and modern codebases and drive improvements pragmatically.
• Experience working in Agile development teams.

Responsibilities

• Develop and maintain a large-scale Java application running in the cloud.
• Analyze business requirements and production issues to design robust, maintainable solutions.
• Work within a complex enterprise monolith and contribute to its continuous evolution.
• Own features end to end, from requirements analysis through implementation, testing, deployment, and production support.
• Collaborate closely with business stakeholders, product teams, and other engineers.
• Communicate technical concepts and solution proposals clearly to both technical and non-technical audiences.
• Create and maintain automated tests to ensure software quality and support continuous delivery.
• Document architectural decisions, design concepts, and implementation approaches.
• Participate in code reviews and contribute to engineering best practices.

Skills

Backend development

Java expertise

Spring Boot

Cloud AWS

Unit testing

CI/CD

Agile teamwork

Tools

Docker

Job description

Payback PL in Warsaw is seeking an accomplished backend engineer to own and evolve a large-scale Java application running in the cloud for Germany’s largest loyalty program. You’ll analyze requirements, fix production issues, and drive robust, maintainable solutions inside a complex monolith.

You will collaborate with business stakeholders and product teams, implement automated tests, document architectural decisions, and contribute to engineering best practices in an agile environment.