The posting
📍 Location: Warsaw or Kraków (hybrid - 2 days in the office per week) 📄 B2B: 170 - 200 PLN / h 🏦 Industry: Financial Services / Payments
We are looking for a Senior Fullstack Engineer to join a team working on a large-scale payment platform used in enterprise environments. The platform enables fast, secure, and multi-channel financial operations.
The role focuses on building and maintaining backend and frontend services, modernizing legacy systems, and improving automation and efficiency. You will work in an Agile, DevOps-aligned environment with experienced teams.
Key Responsibilities:
- Develop and maintain services, microservices, and applications (backend and frontend) using Java 11/17/21 and ReactJS.
- Modernize legacy systems, migrating from mainframe and IBM WebSphere to API/microservice-based architectures.
- Reduce testing costs by implementing automated testing frameworks.
- Improve Straight-Through-Processing (STP) efficiency in services.
- Collaborate closely with DevOps and solution delivery teams.
Requirements:
- Strong experience with Java 11+ (Java 17+ preferred).
- Experience with Kubernetes and Git (required).
- Fluency in navigating Unix-based systems and command-line interfaces.
- Solid knowledge of SQL and relational databases (Oracle preferred).
- Practical understanding of REST APIs and microservice architectures.
- Knowledge of HTTP/Web technologies, JavaScript and React (preferred).
- Experience working in DevOps teams (preferred).
- Understanding of application monitoring (desirable).
- Knowledge of Spring / Spring Boot (desirable).
What We Offer:
- Work on a long-term, large-scale payment platform.
- Real impact on architecture, processes, and modernisation of services.
- Hybrid work model (Warsaw or Kraków).
- Mature engineering environment with focus on automation and best practices.
- Luxmed healthcare package and Multisport card.



