Senior Backend Developer (Node.js/Java)

Salary: 1000-1200pln/md B2B

Work model: Hybrid work from Gdynia / Warszawa / Rzeszów / Kraków

Why choose this offer?

• International working environment
• Freedom in terms of collaboration between team members
• Scandinavian organizational culture providing you with work-life balance
• Getting to know how does the financial products and market works

Project

We are looking for a Senior Backend Developer with strong expertise in Java and Node.js to join a project in the financial sector. The role focuses on designing and developing secure, scalable backend services, including RESTful APIs, Keycloak integration, advanced authorization models, and resilient solutions with caching, error handling, structured logging, and automated testing. The project is delivered for one of the leading European financial groups.

Expected competences and knowledge

• Solid commercial experience with Java and Node.js (Express framework)
• Proven ability to design and implement RESTful APIs tailored to frontend requirements
• Hands-on experience integrating with Keycloak (OIDC, OAuth2, token validation, role enforcement)
• Background in building or working with authorization systems (OpenFGA or similar ACL/ABAC/RBAC models)
• Working knowledge of Redis for session management and caching
• Strong understanding of error handling and building resilient APIs (timeouts, retries, fallback mechanisms)
• Familiarity with structured logging practices, including the use of correlation IDs
• Experience writing unit and integration tests for API endpoints to ensure reliability and maintainability

Technologies you'll work with

• Java / Node.js with Express
• RESTful APIs
• Keycloak (OIDC, OAuth2)
• Authorization systems (OpenFGA or similar)
• Redis
• API resilience patterns (timeouts, retries, fallback)
• Structured logging with correlation IDs
• Unit & integration testing frameworks

Client – why choose this particular client from the Jit portfolio?

Jit Team is proud to partner with one of the leading European financial groups responsible for the registration, ownership records, and financial settlement of securities traded on financial markets in Norway and recently extended to other European markets. Jit Team has been a strategic partner to our client in the area of software development since 2017. Over the course of the partnership, Jit Team's dedicated team working for our client has grown from three to over 30 people, who have worked on the modernization of legacy applications, the implementation of new systems, and the development of a private cloud-based platform to host a variety of financial systems. 

About Jit Team

The Human factor of IT - it's not just a slogan, it's a philosophy. The foundation of Jit Team is people, which is why we prioritise you. We employ over 700 experienced experts. We create highly specialised teams for clients from all over the world. We offer team members developmental projects, a wide range of benefits and a proprietary professional development programme.

Behind our maxim are also charitable and educational activities. We support pupils and students by donating learning equipment. We offer internships to help launch careers in IT. We support water rescuers and hospitals by providing the necessary equipment. We are a Polish company and we share what we have achieved over 15 years of activity. By supporting indigenous initiatives, we ensure the circulation of good energy.