Senior Backend Developer

We are seeking a Senior Backend Developer to design, build, and maintain robust, scalable backend services and APIs powering Client facing Portal applications. The ideal candidate has strong object-oriented development skills, experience with containerized/cloud-native deployment, and the ability to collaborate closely with front-end teams to deliver well-integrated, performant solutions.

What can we offer?

• Start as soon as possible
• B2B Contract or Temporary Employment Contract
• Work mode: Hybrid in Warsaw (3 times per week from office)
• Salary: Up to 190 PLN net+VAT/h (B2B) / Up to 22 350 PLN gross/month (Temp)
• Projectin the banking sector

Requirements:

• At least 8+ years of backend software development experience, with strong expertise in Java or .NET
• Strong Java or .NET development experience (Spring Boot / .NET Core preferred)
• Experience building and consuming REST APIs
• Experience with containerized applications and orchestration (Docker/Kubernetes/OpenShift)
• Working SQL/database experience (relational data modeling, query optimization)
• Familiarity with CI/CD pipelines and automated testing practices

Nice to have:

• Experience with messaging/event-driven architectures (Kafka, MQ, etc.)
• Financial services, fund administration, or transfer agency domain experience
• Exposure to cloud-native development practices

Responsibilities:

• Develop and maintain backend services and RESTful APIs using Java or .NET
• Design data models and integrate with relational/NoSQL databases as required by portal functionality
• Collaborate with front-end developers to define API contracts and ensure smooth integration
• Build and deploy services within containerized environments (Docker/Kubernetes/OpenShift
• Implement secure coding practices, unit/integration testing, and CI/CD pipeline integration
• Optimize service performance, scalability, and reliability
• Troubleshoot and resolve production issues, participating in on-call/support rotations as needed
• Participate in Agile ceremonies, sprint planning, and technical design discussions