dotnet-solid-principles
dotnet-solid-principles
Foundational design principles for .NET applications. Covers each SOLID principle with concrete C# anti-patterns and fixes, plus DRY guidance with nuance on when duplication is acceptable. These principles guide class design, interface contracts, and dependency management across all .NET project types.
Scope boundary: This skill owns foundational SOLID/DRY design principles at the class and interface level. Architectural patterns (vertical slices, request pipelines, caching, idempotency) are owned by [skill:dotnet-architecture-patterns]. DI container mechanics (registration, lifetimes, keyed services) are owned by [skill:dotnet-csharp-dependency-injection]. Code smells and anti-pattern detection are owned by [skill:dotnet-csharp-code-smells].
Cross-references: [skill:dotnet-architecture-patterns] for clean architecture and vertical slices, [skill:dotnet-csharp-dependency-injection] for DI registration patterns and lifetime management, [skill:dotnet-csharp-code-smells] for anti-pattern detection, [skill:dotnet-csharp-coding-standards] for naming and style conventions.
Single Responsibility Principle (SRP)
A class should have only one reason to change. Apply the "describe in one sentence" test: if you cannot describe what a class does in one sentence without using "and" or "or", it likely violates SRP.
Anti-Pattern: God Class
// WRONG -- OrderService handles validation, persistence, email, and PDF generation
public class OrderService
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