| 1 | What is the Options pattern, and why is it preferred over directly injecting IConfiguration into services? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 2 | How do you validate configuration options at application startup to fail fast on misconfiguration? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 3 | What does GetSection and GetValue do differently when reading configuration values in ASP.NET Core? .NET › Configuration & Options | .NET | Configuration & Options | Beginner |
| 4 | How does the order of configuration provider registration affect which value wins when the same key is defined in multiple sources? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 5 | How does the configuration binder handle nested objects, arrays, and complex types when binding a JSON section to a C# class? .NET › Configuration & Options | .NET | Configuration & Options | Advanced |
| 6 | How does named options support configuring multiple distinct instances of the same options type? .NET › Configuration & Options | .NET | Configuration & Options | Advanced |
| 7 | How does the ASP.NET Core configuration system layer multiple sources (appsettings.json, environment variables, command line) together? .NET › Configuration & Options | .NET | Configuration & Options | Beginner |
| 8 | How does configuration hot-reload work with reloadOnChange for appsettings.json, and what are its limitations? .NET › Configuration & Options | .NET | Configuration & Options | Advanced |
| 9 | How do environment variables map to nested configuration keys in ASP.NET Core, given environment variables can't contain colons on some platforms? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 10 | How does the command-line configuration provider let you override settings via arguments when running an application? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 11 | What is the difference between IOptions<T>, IOptionsSnapshot<T>, and IOptionsMonitor<T>? .NET › Configuration & Options | .NET | Configuration & Options | Advanced |
| 12 | How would you write a custom configuration provider to load settings from an unsupported source, like a remote database? .NET › Configuration & Options | .NET | Configuration & Options | Advanced |
| 13 | How would you design configuration for a multi-tenant application where each tenant needs different settings resolved at runtime? .NET › Configuration & Options | .NET | Configuration & Options | Advanced |
| 14 | What is user secrets (dotnet user-secrets), and why should it only be used for local development, never production? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 15 | How does appsettings.{Environment}.json layering work, and how is the current environment determined? .NET › Configuration & Options | .NET | Configuration & Options | Intermediate |
| 16 | What is the Options pattern, and why is it preferred over injecting IConfiguration directly and reading string keys throughout an application? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 17 | What are Configuration and Options pattern in .NET Core? .NET Core › Configuration & Options Pattern | .NET Core | Configuration & Options Pattern | Intermediate |
| 18 | How do you validate configuration options at application startup to fail fast on misconfiguration, using ValidateDataAnnotations and ValidateOnStart? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 19 | How does ASP.NET Core's configuration system layer multiple sources together, and what is the default provider precedence? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Beginner |
| 20 | How does named options support configuring multiple distinct instances of the same options class? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 21 | How does the configuration binder handle nested objects and arrays when binding a JSON section to a strongly-typed C# class? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 22 | How do environment variables map to nested configuration keys, given some shells don't support colons in variable names? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 23 | How does the command-line configuration provider let you override settings via arguments when running an application, and what's its precedence? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 24 | What is the difference between IOptions<T>, IOptionsSnapshot<T>, and IOptionsMonitor<T>, and which is safe to inject into a singleton? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 25 | How does configuration hot-reload work with reloadOnChange for appsettings.json, and what are its limitations? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 26 | How would you write a custom configuration provider to load settings from an unsupported source, like a remote configuration service or database? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 27 | How would you design configuration for a multi-tenant ASP.NET Core application where each tenant needs different settings resolved at runtime? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 28 | How do you write a custom IValidateOptions<T> implementation for validation logic beyond what DataAnnotations attributes can express? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Advanced |
| 29 | How does appsettings.{Environment}.json layering work, and how does ASP.NET Core determine the current environment? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 30 | What is user secrets (dotnet user-secrets), and why should it be used only for local development, never production? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 31 | How do you use IHostEnvironment/IWebHostEnvironment to conditionally configure services based on the current environment? ASP.NET Core › Configuration & Options Pattern | ASP.NET Core | Configuration & Options Pattern | Intermediate |
| 32 | How does System.Text.Json's configuration (via AddJsonOptions) let you customize the default JSON serialization behavior globally? ASP.NET Core › Content Negotiation & Output Formatters | ASP.NET Core | Content Negotiation & Output Formatters | Intermediate |
| 33 | How do 'extends' in tsconfig.json enable sharing a base configuration across multiple projects in a monorepo, and how do overrides get merged? TypeScript › tsconfig & Compiler Options | TypeScript | tsconfig & Compiler Options | Advanced |
| 34 | How do you enable keyspace notifications in Redis, and what do the different configuration character options represent? Redis › Keyspace Notifications | Redis | Keyspace Notifications | Beginner |
| 35 | How would you use Lombok's @EqualsAndHashCode and @ToString annotations to eliminate equals()/hashCode()/toString() boilerplate, and what specific configuration options handle inheritance and field exclusion correctly? Java › equals(), hashCode() & toString() Contracts | Java | equals(), hashCode() & toString() Contracts | Advanced |
| 36 | How do you pass environment-specific configuration into a running .NET container, and how does this interact with the configuration system? .NET › Docker & Containerization | .NET | Docker & Containerization | Intermediate |
| 37 | How does the Generic Host integrate configuration, logging, and dependency injection into a single unified builder? .NET › Generic Host | .NET | Generic Host | Intermediate |
| 38 | How do you configure the Generic Host to read configuration from a custom file format or remote source before the rest of the application starts? .NET › Generic Host | .NET | Generic Host | Intermediate |
| 39 | How do you register a service using a factory delegate instead of a simple type mapping, when construction requires reading configuration or resolving other services conditionally? ASP.NET Core › Dependency Injection | ASP.NET Core | Dependency Injection | Intermediate |
| 40 | How does the Options pattern's IOptions<T>/IOptionsSnapshot<T> relate to and build upon the standard DI container? ASP.NET Core › Dependency Injection | ASP.NET Core | Dependency Injection | Intermediate |
| 41 | How does hosting an ASP.NET Core application in a Docker container change considerations around Kestrel configuration and reverse proxying compared to traditional VM or bare-metal hosting? ASP.NET Core › Hosting Models: Kestrel, IIS & Reverse Proxies | ASP.NET Core | Hosting Models: Kestrel, IIS & Reverse Proxies | Intermediate |
| 42 | How do you manage different configurations for different environments (development, staging, production) using Maven profiles or Gradle's equivalent mechanisms? Java › Build Tools: Maven & Gradle | Java | Build Tools: Maven & Gradle | Intermediate |
| 43 | How would you use an enum to represent a fixed set of configuration keys combined with a shared lookup method, avoiding scattered String literal keys throughout a codebase? Java › Enums | Java | Enums | Intermediate |
| 44 | What is the Options pattern's relationship to DI, and how does IOptions<T> itself get resolved through the container? .NET › Dependency Injection | .NET | Dependency Injection | Advanced |
| 45 | What are the main options for deploying a Next.js application? Next.js › Deployment | Next.js | Deployment | Beginner |
| 46 | How do you configure PM2 using an ecosystem.config.js file rather than passing options directly on the command line? Node.js › Deployment & Process Managers (PM2) | Node.js | Deployment & Process Managers (PM2) | Intermediate |
| 47 | What is IMemoryCache, and when is it appropriate to use for caching in ASP.NET Core? .NET › Caching (In-Memory, Distributed & Redis) | .NET | Caching (In-Memory, Distributed & Redis) | Beginner |
| 48 | What is the difference between role-based and claims-based authorization in ASP.NET Core? ASP.NET Core › Authorization | ASP.NET Core | Authorization | Beginner |
| 49 | What is IMemoryCache, and when is it appropriate for an ASP.NET Core application? ASP.NET Core › Caching | ASP.NET Core | Caching | Beginner |
| 50 | What is dependency injection, and how does ASP.NET Core's built-in DI container support it out of the box? ASP.NET Core › Dependency Injection | ASP.NET Core | Dependency Injection | Beginner |
| 51 | How do you exclude a globally-registered filter from running on one specific action or controller? ASP.NET Core › Filters | ASP.NET Core | Filters | Beginner |
| 52 | What is Kestrel, and how does its role in ASP.NET Core hosting differ from a traditional web server like IIS? ASP.NET Core › Hosting Models: Kestrel, IIS & Reverse Proxies | ASP.NET Core | Hosting Models: Kestrel, IIS & Reverse Proxies | Beginner |
| 53 | What is the difference between Kestrel's ListenAnyIP and Listen methods for binding to network addresses? ASP.NET Core › Hosting Models: Kestrel, IIS & Reverse Proxies | ASP.NET Core | Hosting Models: Kestrel, IIS & Reverse Proxies | Beginner |
| 54 | How would you get the current date and time, and how does specifying an explicit ZoneId (versus relying on the system default) affect the result of LocalDate.now() or LocalDateTime.now()? Java › Java Date & Time API (java.time) | Java | Java Date & Time API (java.time) | Beginner |
| 55 | How do you configure and use Redis as a distributed cache in ASP.NET Core with StackExchange.Redis? .NET › Caching (In-Memory, Distributed & Redis) | .NET | Caching (In-Memory, Distributed & Redis) | Intermediate |
| 56 | How do you securely manage secrets (connection strings, API keys) in a CI/CD pipeline without committing them to source control? .NET › CI/CD, Publishing & Deployment | .NET | CI/CD, Publishing & Deployment | Intermediate |
| 57 | What is the purpose of separate build and release pipelines (or stages), and why shouldn't you rebuild the application for each deployment environment? .NET › CI/CD, Publishing & Deployment | .NET | CI/CD, Publishing & Deployment | Intermediate |
| 58 | How do feature flags decouple code deployment from feature release in a CI/CD workflow? .NET › CI/CD, Publishing & Deployment | .NET | CI/CD, Publishing & Deployment | Intermediate |
| 59 | How do you configure CORS to allow requests only from multiple specific origins, such as both a production and staging frontend? .NET › CORS & Cross-Origin Resource Sharing | .NET | CORS & Cross-Origin Resource Sharing | Intermediate |
| 60 | What is the difference between Singleton, Scoped, and Transient service lifetimes in ASP.NET Core's DI container? .NET › Dependency Injection | .NET | Dependency Injection | Intermediate |
| 61 | How do you register multiple implementations of the same interface, and how do you resolve all of them together? .NET › Dependency Injection | .NET | Dependency Injection | Intermediate |
| 62 | How do you register a service using a factory delegate instead of a simple type mapping, when construction requires custom logic? .NET › Dependency Injection | .NET | Dependency Injection | Intermediate |
| 63 | What is IHostEnvironment, and how do you use it to conditionally configure services based on the current environment? .NET › Generic Host | .NET | Generic Host | Intermediate |
| 64 | How do you combine multiple authorization requirements within a single policy, and how are they evaluated (AND vs OR logic)? ASP.NET Core › Authorization | ASP.NET Core | Authorization | Intermediate |
| 65 | How do you implement a periodic scheduled task using PeriodicTimer instead of Task.Delay, and what problem does it solve? ASP.NET Core › Background Tasks & Hosted Services | ASP.NET Core | Background Tasks & Hosted Services | Intermediate |
| 66 | What is IDistributedCache, and how does it differ from IMemoryCache in a horizontally-scaled ASP.NET Core deployment? ASP.NET Core › Caching | ASP.NET Core | Caching | Intermediate |
| 67 | How does the newer Output Caching middleware (introduced in .NET 7) differ from Response Caching middleware? ASP.NET Core › Caching | ASP.NET Core | Caching | Intermediate |
| 68 | How does HybridCache (introduced in .NET 9) unify in-memory and distributed caching, and what problems does it solve? ASP.NET Core › Caching | ASP.NET Core | Caching | Intermediate |
| 69 | How do you configure Redis as the backing distributed cache for both IDistributedCache and Output Caching in the same application? ASP.NET Core › Caching | ASP.NET Core | Caching | Intermediate |
| 70 | How do you register multiple implementations of the same interface and resolve all of them together via IEnumerable<T>? ASP.NET Core › Dependency Injection | ASP.NET Core | Dependency Injection | Intermediate |
| 71 | How do you apply a filter globally to every controller action, versus scoping it to a specific controller or individual action? ASP.NET Core › Filters | ASP.NET Core | Filters | Intermediate |
| 72 | How do you enable and use gRPC reflection for service discovery and debugging tools like grpcurl or Postman? ASP.NET Core › gRPC Services | ASP.NET Core | gRPC Services | Intermediate |
| 73 | How do you implement a custom health check by implementing IHealthCheck, such as checking database connectivity? ASP.NET Core › Health Checks | ASP.NET Core | Health Checks | Intermediate |
| 74 | How do you add pre-built health checks for common external dependencies like SQL Server, Redis, or a URL endpoint, using the community AspNetCore.Diagnostics.HealthChecks packages? ASP.NET Core › Health Checks | ASP.NET Core | Health Checks | Intermediate |
| 75 | What is the difference between the in-process and out-of-process hosting models when running an ASP.NET Core application under IIS? ASP.NET Core › Hosting Models: Kestrel, IIS & Reverse Proxies | ASP.NET Core | Hosting Models: Kestrel, IIS & Reverse Proxies | Intermediate |
| 76 | What role does a reverse proxy play in TLS/SSL termination, and why is this pattern common in production deployments? ASP.NET Core › Hosting Models: Kestrel, IIS & Reverse Proxies | ASP.NET Core | Hosting Models: Kestrel, IIS & Reverse Proxies | Intermediate |
| 77 | What is a self-signed certificate, and why is the ASP.NET Core development HTTPS certificate (dotnet dev-certs) not suitable for production use? ASP.NET Core › HTTPS, Certificates & Transport Security | ASP.NET Core | HTTPS, Certificates & Transport Security | Intermediate |
| 78 | How does the UseHttpsRedirection() middleware determine which port to redirect to, and how do you explicitly configure it when the HTTPS port isn't on the default 443? ASP.NET Core › HTTPS, Certificates & Transport Security | ASP.NET Core | HTTPS, Certificates & Transport Security | Intermediate |
| 79 | What is a Maven BOM (Bill of Materials), and how does it help manage consistent dependency versions across a multi-module project or organization? Java › Build Tools: Maven & Gradle | Java | Build Tools: Maven & Gradle | Intermediate |
| 80 | What is the significance of storing date-time values in UTC in a database or when transmitting between systems, rather than storing them in a specific local timezone? Java › Java Date & Time API (java.time) | Java | Java Date & Time API (java.time) | Intermediate |
| 81 | What is Dependency Injection (DI) in .NET Core? How is it implemented? .NET Core › Dependency Injection in .NET Core | .NET Core | Dependency Injection in .NET Core | Intermediate |
| 82 | What is Entity Framework Core (EF Core)? How is it different from EF6? .NET Core › Entity Framework Core | .NET Core | Entity Framework Core | Intermediate |
| 83 | How do you integrate external identity providers (Google, Microsoft Entra ID, Facebook) using OAuth/OpenID Connect in ASP.NET Core? .NET › Authentication & Authorization (Identity, JWT, OAuth) | .NET | Authentication & Authorization (Identity, JWT, OAuth) | Advanced |
| 84 | How does HybridCache (introduced in .NET 9) combine in-memory and distributed caching to solve common pain points? .NET › Caching (In-Memory, Distributed & Redis) | .NET | Caching (In-Memory, Distributed & Redis) | Advanced |
| 85 | What are keyed services (introduced in .NET 8), and what problem do they solve compared to multiple unnamed registrations? .NET › Dependency Injection | .NET | Dependency Injection | Advanced |
| 86 | How does exception handling middleware interact with model validation errors in ASP.NET Core, and how do they typically produce different error response paths? .NET › Global Exception Handling & Middleware | .NET | Global Exception Handling & Middleware | Advanced |
| 87 | How would you design exception handling middleware to support internationalized (localized) error messages returned to clients in different languages? .NET › Global Exception Handling & Middleware | .NET | Global Exception Handling & Middleware | Advanced |
| 88 | How do you combine multiple version reader strategies (e.g., both URL segment AND header) to give clients flexibility in how they specify a version? ASP.NET Core › API Versioning | ASP.NET Core | API Versioning | Advanced |
| 89 | How does JWT bearer authentication validate an incoming token, and what claims does TokenValidationParameters check? ASP.NET Core › Authentication | ASP.NET Core | Authentication | Advanced |
| 90 | How do external identity provider integrations (like Google or Microsoft Entra ID) work using OAuth/OpenID Connect authentication handlers? ASP.NET Core › Authentication | ASP.NET Core | Authentication | Advanced |
| 91 | How would you implement a custom IAuthorizationRequirement and IAuthorizationHandler for a business rule like 'only during business hours'? ASP.NET Core › Authorization | ASP.NET Core | Authorization | Advanced |
| 92 | How would you design an authorization system supporting dynamically-configurable, admin-managed permissions rather than hardcoded policies in code? ASP.NET Core › Authorization | ASP.NET Core | Authorization | Advanced |
| 93 | How would you implement a cron-like scheduled background job (e.g., 'run daily at 2 AM') without a third-party scheduling library? ASP.NET Core › Background Tasks & Hosted Services | ASP.NET Core | Background Tasks & Hosted Services | Advanced |
| 94 | How do you configure CORS to allow multiple specific known origins simultaneously, such as production, staging, and local development? ASP.NET Core › CORS (Cross-Origin Resource Sharing) | ASP.NET Core | CORS (Cross-Origin Resource Sharing) | Advanced |
| 95 | What are keyed services (introduced in .NET 8), and what problem do they solve compared to injecting IEnumerable<T> when you need one specific implementation? ASP.NET Core › Dependency Injection | ASP.NET Core | Dependency Injection | Advanced |
| 96 | How does dependency injection integrate with minimal API endpoint handlers versus controller constructors? ASP.NET Core › Dependency Injection | ASP.NET Core | Dependency Injection | Advanced |
| 97 | How would you design exception handling to support internationalized (localized) error messages returned to different clients in their preferred language? ASP.NET Core › Error Handling | ASP.NET Core | Error Handling | Advanced |
| 98 | How does an IAsyncActionFilter differ from the synchronous IActionFilter, and why is the async version generally preferred for filters doing I/O work? ASP.NET Core › Filters | ASP.NET Core | Filters | Advanced |
| 99 | How do you control the execution order of multiple filters of the same type applied to a single action? ASP.NET Core › Filters | ASP.NET Core | Filters | Advanced |
| 100 | How would you integrate health check results with the AspNetCore.HealthChecks.UI package to get a persistent, historical dashboard view of health status over time? ASP.NET Core › Health Checks | ASP.NET Core | Health Checks | Advanced |
| 101 | What is YARP (Yet Another Reverse Proxy), and how does it compare to nginx or IIS as a reverse proxy option for ASP.NET Core applications? ASP.NET Core › Hosting Models: Kestrel, IIS & Reverse Proxies | ASP.NET Core | Hosting Models: Kestrel, IIS & Reverse Proxies | Advanced |
| 102 | How would you configure Kestrel to use a specific X.509 certificate for HTTPS, and what are the different ways to supply that certificate (file-based, certificate store, Azure Key Vault)? ASP.NET Core › HTTPS, Certificates & Transport Security | ASP.NET Core | HTTPS, Certificates & Transport Security | Advanced |
| 103 | How would you implement Server Name Indication (SNI)-based certificate selection in Kestrel, serving different TLS certificates for different hostnames on the same IP/port? ASP.NET Core › HTTPS, Certificates & Transport Security | ASP.NET Core | HTTPS, Certificates & Transport Security | Advanced |
| 104 | How would you handle adding behavior to an enum where the number of constants might grow very large or needs to be data-driven rather than hardcoded at compile time, and why might a class-based registry be more appropriate in that scenario? Java › Enums | Java | Enums | Advanced |
| 105 | What are .NET Core Hosting Models? .NET Core › .NET Core Hosting Models | .NET Core | .NET Core Hosting Models | Advanced |