About the Role
What is flexhub? 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. What's in it for you: Consulting variety meets corporate stability. You join different teams across the bank when your expertise is needed, then move on to the next challenge. This approach helps you build strong internal know-how and gives you the chance to contribute to meaningful work – one initiative at a time – without sales targets or utilization pressure. No selling. Just a consistent focus on engineering solutions that matter. As a Specialist Backend Developer at flexhub, you drive the technical quality and architecture of our core systems. You architect scalable solutions, mentor junior colleagues, and solve the most difficult engineering problems we face. Your deep expertise in Java and distributed systems allows you to make decisions that last. You are the technical anchor your team relies on to deliver excellence. Your main tasks are: Primary Action: Architect and build critical backend services that handle high transaction volumes. Integration: Define interface contracts and ensure data consistency across distributed systems. Implementation: Solve complex concurrency and memory management issues in our applications. Quality: Establish testing strategies and ensure the team adheres to security best practices. Collaboration: Guide the team during technical planning and help resolve blockers. Operations: Analyse production metrics to identify bottlenecks and plan capacity. Documentation: Write architectural decision records (ADRs) to track important technical choices. Learning: Mentor junior and professional developers to help them advance their careers. Stakeholder: Advise product management on technical feasibility and risks of new features. Improvement: Drive the adoption of new tools or frameworks that increase developer productivity. What is important for us? 👌 Proficient in Java and JavaScript . Hands-on experience with the Spring Framework . Strong knowledge of RESTful Web Services and APIs. Solid command of SQL for database operations and querying. Skilled in Git for version control and collaborative workflows. Competency in Object-Oriented Design principles. Expertise in writing and executing Unit Tests . Familiar with Agile methodologies , including Scrum or Kanban. How? 📌 Hybrid on Ogrodowa 8 or Wersalska 6 street Łódź What we offer? 🥳 Of course, we offer Development Plans for employees, Life insurance , flexible working hours , integration events and much more 😎 * * * 🚩 Please add the following clause to your application: 1. I consent to the processing of personal data contained in this document by Commerzbank AG with its registered office in Frankfurt am Main, Germany, 60261 Kaiserplatz, operating through the Branch in Poland with its registered office in Łódź, 91-203 Łódź, ul. Wersalska 6, KRS 0000631053, for the implementation of the current recruitment process and for the future recruitment for a period of 6 months, in accordance with the Regulation of the European Parliament and of the Council (EU) 2016/679 of 27 April 2016 on the protection of individuals with regard to the processing of personal data the free flow of such data and the repeal of Directive 95/46 / EC (RODO) and in accordance with the Act of 10 May 2018 on the protection of personal data (Journal of Laws of 2018, item 1000). I provided my personal data voluntarily and I declare that they are truthful. I have the right to withdraw this consent at any time. The withdrawal of consent shall not affect the lawfulness of processing based on consent before its withdrawal. 2. I have read the content of the information clause, including information about the purpose and methods of processing personal data and the right to access to my personal data and about the right to correct, rectify and delete it.