Senior Full-Stack Engineer (.NET / React / Azure / Terraform)
About the role
We are looking for a Senior Full-Stack Engineer to join a large-scale modernization programme focused on migrating a portfolio of legacy applications and databases to a modular, cloud-native architecture on Microsoft Azure. You will work across backend, frontend, database and cloud/DevOps areas, contributing directly to production solutions and supporting the incremental transformation of business-critical systems.
Your responsibilities
- Design and implement backend services and REST APIs in .NET 9 using Clean Architecture.
- Build and maintain React and TypeScript microfrontends integrated through module federation.
- Develop and optimize MSSQL and Azure SQL schemas, stored procedures, views and EF Core queries.
- Create and maintain Terraform code for provisioning Azure resources across environments.
- Build, optimize and support Azure DevOps CI/CD pipelines using YAML.
- Integrate Entra ID / MSAL authentication and apply security best practices, including Key Vault and least-privilege access.
- Implement observability with Application Insights, structured logging, health checks and alerting.
- Refactor legacy .NET and T-SQL solutions and extract business logic during migration.
- Create and maintain unit, integration, API and end-to-end automated tests.
- Troubleshoot production incidents, deliver fixes and support deployments.
- Collaborate in Agile ceremonies, estimate work, define acceptance criteria and participate in code reviews.
Required skills and experience
- At least 5 years of commercial full-stack development experience with C# and .NET, including .NET 6+ and ASP.NET Core.
- Strong knowledge of EF Core and MSSQL / Azure SQL, including query tuning, indexing, transactions and stored procedures.
- Hands-on experience with Azure services such as App Service, Azure SQL, Storage, Key Vault, Functions and Service Bus.
- Practical experience with Infrastructure as Code using Terraform, including modules, state management and multi-environment provisioning.
- Experience with Azure DevOps CI/CD and YAML pipelines.
- Experience building and securing REST APIs, including validation, versioning, OAuth, JWT and Entra ID.
- Experience with automated testing tools such as xUnit, Jest, Vitest or Playwright.
- Knowledge of Application Insights, OpenTelemetry and structured logging.
- Good Git practices and code review discipline.
- English at B2 level or higher for technical communication.
Nice to have
- Production experience with React and TypeScript.
- Experience with Azure Data Factory, Databricks, Spark, Power BI or SSRS.
- Knowledge of microfrontends and module federation.
- Experience with Docker and Kubernetes / AKS.
- Knowledge of Bicep or ARM templates.
- Experience with event-driven integration using Service Bus or Event Hubs.
- Experience modernizing legacy technologies such as ASP.NET MVC, Razor, WPF, WinForms, Windows Services or SSIS.
- Azure certifications such as AZ-204, AZ-400 or AZ-104, or HashiCorp Terraform Associate.
What we offer
- Hybrid work in Kraków, with 6 days per month in the office.
- B2B contract
- Rate : 160 -185 PLN netto/hour
- Benefits: Luxmed, Multisport Card