Senior .NET Developer

For our client in the public sector, we are seeking a Senior .NET Developer fluent in Lithuanian to join a high-impact project delivering robust backend systems and APIs for fast, secure, and scalable information access. The project involves developing a system that enables efficient information filtering and access while working with a modern tech stack, including C#, Keycloak, OpenShift, YARP, Grafana, Sentry, Parquet, and SPARQL. Key Requirements:  Strong experience with C#/.NET Core for scalable backend and API service development Hands-on experience with containerized deployments (OpenShift/Kubernetes) Expertise in API Gateway & Proxy development: request routing, logging, monitoring, auditing, rate limiting, retries, and resilience Identity & Security: integrating with Keycloak (OAuth2.0/OpenID Connect), JWT validation, secure API design Knowledge of observability and audit: structured logging, distributed tracing, metrics, audit trails Proficient in integration with external systems Experience with asynchronous processing (workers/event-driven, queue handling, retry/DLQ strategies) Experience with CI/CD, secure coding, and advanced testing practices Fluency in Lithuanian is mandatory Nice to Have: Familiarity with YARP, Grafana, Sentry, Parquet, SPARQL Prior experience in the public sector or large-scale information systems Responsibilities: Design, develop, and maintain scalable .NET Core backend services and APIs Implement API Gateway and Proxy solutions, ensuring reliability, security, and observability Integrate identity management solutions using Keycloak, JWT, and OAuth2.0/OpenID Connect Implement asynchronous processing pipelines, message queues, and retry/DLQ strategies Collaborate with cross-functional teams to deliver secure, maintainable, and efficient systems Apply CI/CD, secure coding, and automated testing best practices Ensure proper monitoring, logging, and auditing across all services Maintain documentation and participate in code reviews, troubleshooting, and performance optimization Work Conditions: Project: Public Sector Location: Remote from Lithuania Start Date: ASAP End Date: 2026-04-01 Contract Type: B2B Salary: 25-34 EUR/h If you're passionate about building secure, scalable, and high-performance backend solutions and want to make a tangible impact on public sector services, we'd love to hear from you!