Senior .NET backend developer

As of 2 September 2025, Tietoevry Tech Services, earlier part of Tietoevry Group, will operate as a standalone company. We'll soon be operating under a new name: Vivicta. You will discover more about our new brand by the end of the year.Read more.You may apply by selecting Apply and fill your application details to the form. You may also Apply by using LinkedIn and populate details to your application from your LinkedIn profile.Who we are:We are small internal development team. We are part of a large international Tietoevry Tech Services Security Team located in Finland, Norway, Sweden and Czechia. We are looking for Senior .NET Software Developer who will work with us on our internal SOAR platform which we are running for more than ten years.The whole platform is written in C# with TDD approach and is based on a set of Windows services, WPF desktop application, REST API, .NET Core, MS SQL Cluster, Elasticsearch stack, Apache NiFi, Apache Kafka, and Power BI. We have integrated many on-premises and cloud platforms for the Security Operations Center and other divisions of Managed Security Services. The platform provides centralized monitoring, data transfers, automation, reporting, response support, remote system control, user-defined workflows, and interactive playbooks for hundreds of thousands of devices and users.In our team, we are heavily focused on code quality, people's ideas, and professional growth. If you have an idea or want to experiment with some promising technology, you have free hands. We have reserved a regular day per sprint for the learning to keep our people on a good technical level. Besides traditional code review for every pull request and automated builds, we have also regular tasks for continuous code quality improvement to avoid some legacy code or security risks.With us as a Senior .NET Backend Developer:you will be a key contributor to the development of our SOAR platform. Your responsibilities will include:Designing and building the backend layer, including:Developing the DataLayer on top of Microsoft SQL Server, with a focus on schema design and query optimizationImplementing and consuming REST APIs for integration with security providers (Azure, AWS, Google Cloud) and 3rd-party security toolsExtending our custom workflow engine, enrichment APIs, and backend logicParticipating in the development of the web portal and reporting infrastructureWorking on AI-driven features to enhance the efficiency of Security Operations, such as:Alert classification, summarization, and triage using models like OpenAI / Azure OpenAIAutomating playbook actions and recognizing patterns that trigger automated responsesWe expect you to have:Strong experience with C#Proficiency in T-SQL, Entity Framework, and Dapper, including hands-on work with database schema design and query optimizationSolid understanding of REST APIs:Creating and consuming endpointsFamiliarity with Swagger/OpenAPI, OAuth2, JWT, OpenID, and Role-Based Access Control (RBAC)Experience with Test-Driven Development (TDD) and mocking frameworksProficient in:Asynchronous programming, parallelismEfficient memory usage (Span, Memory)Writing high-performance backend codeKnowledge of Dependency Injection, CQRS, Mediator pattern, and event-driven architecturesHands-on experience integrating with OpenAI, Azure OpenAI, or similar APIs (e.g., ChatGPT, GPT-4)Bonus Points / Nice to Have:Experience with SignalR, Apache Kafka, or Azure Service BusExposure to prompt engineering and building intelligent UI/UX powered by LLMsIntegration of ML workflows using ML.NET or other .NET-compatible ML toolsKnowledge of Elasticsearch / Kibana developmentExperience with ASP.NET Core, Blazor, TypeScript, or modern web technologiesWorking in Agile (SCRUM) environments with Git (Azure DevOps), JIRAAwareness of security best practices in backend developmentWe offer:Contract is for an indefinite period of time > we count on youwork partially or completely remote > work from wherever it suits youextra holidays > we have 25 days off plus 2 sick days.we contribute from CZK per year > you name it. Choose from contributions for pension and life insurance, sports, culture, health, travel or education in the cafeteria.educate yourself > we regularly organize and pay for IT courses, certifications, language training and personal development courses107 CZK meal allowance on top of your salaryreward for a new colleague > refer another colleague to us and get up to 80,000 CZKwe'll support you when you're sick > for colleagues who are seriously ill for a long period of time, we contribute to sick pay in excess of the lawextra work is appreciated > when overtime is needed, we pay more than the law requiresstay fit and fresh > in Ostrava, use the free fitness facilities in the building, in other locations, do sports with MultisportNordic culture > we believe in you. No one is breathing down your neck and checking every minute of your work. We are friendly and open.LI-HybridLI-TM1