Senior Backend Developer (Java /.NET)

About the Position

We are seeking a Senior Backend Developer with 8+ years of experience in Java or .NET to join our team in Warsaw, Poland, building scalable backend services and APIs.

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.

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

About the Company

Experis Manpower Group is a leading provider of workforce solutions, offering a wide range of services to help businesses thrive. We are committed to delivering excellence and innovation in every project we undertake.