C# Patterns

When to Activate

• Writing C# 12 / .NET 8+ source files (.cs, .razor)
• Designing domain models with records and value objects
• Building ASP.NET Core Web APIs with MediatR
• Reviewing C# code for idiomatic patterns and async correctness
• Implementing CQRS handlers, repositories, or application services in a .NET project
• Choosing between class hierarchies and discriminated unions via the Result pattern
• Setting up Entity Framework Core with separate configuration classes and owned types

Records — Immutable Data Transfer

// Positional record — equality by value, deconstruction, with-expression
public sealed record User(int Id, string Name, Email Email, DateTimeOffset CreatedAt);