Feature Flags in C#: Patterns That Actually Work | Branches That Don't Suck #6
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Video Description
Feature flags are powerful, but they can turn your codebase into spaghetti if you're not careful. Magic strings scattered everywhere. No way to find all usages. Impossible to test.
In this video, I'll show you the patterns I've used in production systems for years — patterns that keep your code clean, testable, and maintainable.
What you'll learn: • The interface-based feature management pattern • Why typed boolean properties beat magic strings (compiler safety!) • Three implementation patterns: feature gating, version switching, and user-specific flags • How to create a mock for easy unit testing • Wiring it up with dependency injection • Common mistakes and how to avoid them
Code patterns covered: • IFeatureManager interface • FeatureManager implementation with dictionary lookup • MockFeatureManager for testing • Controller examples with flag checks • User-specific flags for private betas • DI registration in ASP.NET Core
#csharp #dotnet #featureflags #aspnetcore #cleancode #unittesting
0:00 Feature Flags in C#: Patterns That Actually Work 0:22 What makes feature flags messy? 0:42 Interface-Based Feature Management 1:32 The Interface 1:59 Why Typed Properties? 3:01 The Implementation 3:29 Pattern 1: Feature Gating 3:57 Pattern 2: Version Switching 4:26 Pattern 3: User-Specific Flags 5:01 The Mock for Testing 5:23 Testing With Feature Flags 5:48 Wiring It Up 6:21 Common Mistakes 7:04 Quick Recap 7:47 Thanks for Watching
Video Info
- Duration: 7:52
- Published: January 30, 2026
