C# & .NET 8 Architect Mastery

Reflection & Attributes: Building custom frameworks

1 Views Updated 5/4/2026

Mastering Reflection

Reflection allows your code to See itself. You can inspect types, find methods, and even execute code on objects you've never seen before. It is how tools like Entity Framework and JSON.NET work.

1. Custom Attributes

Attributes are "Metadata" that you attach to your code. By using Reflection, you can find all classes with a specific attribute (e.g., `[AutoRegister]`) and automatically add them to your DI container at startup. Architect Tip: This eliminates the need for giant, manual configuration files.

2. Performance Warning

Reflection is slow. It requires the CLR to search through internal tables. To fix this, use **Caching**. Reflect on the type ONCE, find the method you need, and store a **Delegate** to that method in a static dictionary. Subsequent calls will be nearly as fast as direct code.

4. Interview Mastery

Q: "What is the difference between 'Early Bound' and 'Late Bound' code?"

Architect Answer: "**Early Bound** is normal code. The compiler knows exactly what method you are calling at compile time. **Late Bound** is when you use Reflection or `dynamic`. You don't know what you are calling until the app is actually running. Early Bound is faster and safer, while Late Bound provides maximum flexibility for building highly extensible plugin systems."

C# & .NET 8 Architect Mastery
1. Memory Management & Performance
The CLR Deep Dive: Stack, Heap, and Garbage Collection (GC) Value Types vs Reference Types: Structs, Records, and Classes Span<T> and Memory<T>: Zero-copy high-performance code Benchmarking with Benchmark.DotNet: Measuring nano-seconds
2. Advanced Asynchronous Programming
Async/Await Internals: The State Machine and TaskContext ValueTask vs Task: Avoiding allocation in hot paths Task.WhenAll vs Parallel.ForEachAsync: Concurrency at scale Thread Safety & Multi-threading: Locks, Semaphores, and Interlocked
3. Modern C# 12+ Features
Primary Constructors & Collection Expressions Pattern Matching: Switch expressions and Recursive patterns Required Members & Init-Only properties Native AOT (Ahead of Time): Deployment for serverless/edge
4. Enterprise Design Patterns in .NET
Dependency Injection (DI): Lifetime management and Captive Dependencies The Options Pattern: Type-safe configuration management The Factory & Builder Patterns in Modern .NET Middleware Architecture: Building custom ASP.NET Core pipelines
5. Dynamic Programming & Reflection
Reflection & Attributes: Building custom frameworks Expression Trees: Building dynamic LINQ queries Source Generators: Compile-time code generation for speed Dynamic Types & ExpandoObject: When and when not to use them
6. Testing & Quality Architecture
Unit Testing Patterns: xUnit, Moq, and FluentAssertions Integration Testing with WebApplicationFactory Mutation Testing: Testing the quality of your tests TDD (Test Driven Development) for Senior Architects
7. Modern Web API Architectures
Minimal APIs vs Controllers: Choice of architecture Rate Limiting & Throttling in ASP.NET Core Versioning Strategies: URL vs Header vs Media Type Real-time Web with SignalR and WebSockets
8. FAANG .NET Architect Interview
Case Study: Designing a High-Throughput Payment Gateway in .NET Case Study: Solving Memory Leaks and CPU Spikes in Production