• When undertaking a significant refactoring effort on a critical ASP.NET Core application hosted in Azure , what strategies would you use to minimize risk ? Discuss the role of automated testing (unit, integration, performance) and safe deployment techniques like Blue-Green deployments or feature flags managed via Azure App Configuration .

  • Scenario: A legacy ASP.NET Core application uses static helper classes extensively, hindering testability and flexibility. Propose a refactoring strategy using Dependency Injection principles in C , making the application more suitable for containerization and deployment to Azure Container Instances or AKS .(Mid to Expert Level)

  • How would you address the "Primitive Obsession" code smell in an ASP.NET Core application by refactoringCcode to use strongly-typed domain objects or value objects ? What benefits does this provide when interacting with Azure services or message queues ?

  • Describe the process of refactoring an ASP.NET Core application to implement distributed caching using Azure Cache for Redis . What parts of the C codebase would you target, and what considerations are important for cache invalidation and consistency ?

  • You need to refactor the authentication mechanism of an ASP.NET Core application from a custom solution or Windows Authentication to use Azure Active Directory (AAD) or Azure AD B2C . Describe the key areas of code modification and configuration changes within the Azure portal .

  • How would you refactor synchronous Ccode blocks (e.g., blocking I/O calls, long-running CPU-bound tasks) within an ASP.NET Core application to use asynchronous patterns (async/await) ? Why is this crucial for scalability in Azure environments like App Service ?

  • When refactoring an ASP.NET Core application initially designed for on-premises deployment to run effectively on Azure PaaS (e.g., App Service, Functions), what specific code patterns related to state management , configuration , or resource access need careful review and modification?

  • Refactoring for testability: If an ASP.NET Core application passes HttpContext or other framework-specific dependencies deep into business logic layers , how would you refactor the C code using patterns like Dependency Injection to decouple it and make it unit-testable , especially when considering components might run in different Azure compute environments ?

  • Discuss the refactoring challenges and strategies involved when migrating the data persistence layer of an ASP.NET Core application, for instance, moving from Entity Framework Core with an on-premises SQL Server to using Azure Cosmos DB or Azure Table Storage . What code adjustments are typically required? Expertise Level: Advanced

  • How do you approach identifying, prioritizing, and refactoring technical debt in an existing ASP.NET Core application running on Azure ? What specific code smells or anti-patterns related to cloud deployment would you look for?

  • Explain how you would apply the "Strangler Fig" pattern to incrementally refactor a legacy ASP.NET monolithic application towards an ASP.NET Core microservices architecture hosted on Azure Kubernetes Service (AKS) or Azure App Service .

  • You have an ASP.NET Core application where business logic is tightly coupled within API controllers and relies heavily on direct database access . How would you refactor this to improve separation of concerns , enhance testability , and potentially leverage Azure services like Azure Functions or Azure SQL Database more effectively?

  • Describe a situation where you refactored a large C method in an ASP.NET Core controller . What code smells were you addressing, what techniques did you use (e.g., Extract Method ), and how did you ensure the refactoring didn't introduce regressions , particularly considering its deployment on Azure ?