Senior Backend Developer (Java / .NET)

Backend Developer (Java or .NET)

Location: Warsaw (Hybrid - 3 days per week in the office)
Start Date: ASAP / Flexible
Cooperation Model: B2B via Experis

We are looking for an experienced Backend Developer to join an international team building and maintaining scalable backend services and APIs powering client-facing portal applications.

Responsibilities

• Develop and maintain backend services and REST APIs using Java (Spring Boot) or .NET Core.

• Design and integrate solutions with relational and NoSQL databases.

• Collaborate closely with frontend teams to deliver seamless integrations.

• Build and deploy applications in containerized environments using Docker, Kubernetes, or OpenShift.

• Implement secure coding practices, automated testing, and CI/CD pipelines.

• Optimize application performance, scalability, and reliability.

• Troubleshoot production issues and support application stability.

• Participate in Agile ceremonies and technical design discussions.

Requirements

• 8+ years of backend development experience.

• Strong expertise in Java or .NET.

• Hands-on experience building and consuming REST APIs.

• Experience with Docker, Kubernetes, or OpenShift.

• Solid SQL and database knowledge.

• Experience with CI/CD pipelines and automated testing.

• Strong communication and teamwork skills.

Nice to Have

• Experience with Kafka, MQ, or other messaging technologies.

• Cloud-native development experience.

• Background in financial services, fund administration, or transfer agency environments.

What We Offer

• B2B contract via Experis

• Hybrid work model (Warsaw, 3 days per week in the office)

• Long-term international projects

• Medicover healthcare package

• Multisport card

• Group life insurance