[Hiring] Fullstack Developer @Commerzbank AG – Poland

Role Description

Join our FlexHub team as a Fullstack Developer!

As a Specialist Fullstack Developer at FlexHub, you drive the technical quality and architecture of our integrated systems. You architect scalable solutions, mentor junior colleagues, and solve the most difficult engineering problems we face. Your deep expertise in both Java and frontend architectures allows you to make decisions that last. You are the technical anchor your team relies on.

What will you be doing?

• Design and develop critical full-stack modules capable of handling high transaction volumes.
• Define interface contracts and ensure data consistency across distributed systems.
• Solve complex technical challenges, including concurrency and memory management issues.
• Define testing strategies and ensure adherence to security and development best practices.
• Support the team during technical planning and help resolve technical blockers.
• Analyse production metrics to identify bottlenecks and support capacity planning.
• Document key architectural decisions using Architectural Decision Records (ADRs).
• Mentor and support developers, helping them grow their technical skills and advance their careers.
• Advise Product Management on the technical feasibility, complexity, and risks of new features.
• Drive continuous improvement by introducing tools, frameworks, and practices that increase developer productivity and software quality.

Qualifications

• Hands-on experience with Java and React.
• Experience with RESTful Web Services.
• Good knowledge of SQL, HTML5, and Git.
• Experience with unit testing.
• Good understanding of object-oriented design principles.
• Experience working with Agile methodologies.
• Fluency in English and Polish, both at a minimum B2 level.
• Strong analytical and problem-solving skills, with attention to detail.
• Customer-oriented mindset with a proactive approach and a strong sense of ownership.
• Ability to deliver high-quality results on time.
• Excellent communication and collaboration skills.
• Flexibility and ability to adapt to a fast-changing environment.
• A strong team player, comfortable working in international and cross-functional teams.

Benefits

• Development Plans for employees.
• Life insurance.
• Flexible working hours.
• Integration events.
• And much more.

Company Description

We are Commerzbank's internal delivery capability – a team of engineers, architects, analysts and experts working directly with business units. Unlike external consultancies, we are colleagues who stay. Based in Frankfurt, Sofia, and Łódź, we drive high-priority initiatives while building internal expertise that lasts.