When implementing feature flags, ensure consistency between runtime and compiled scenarios. Feature switches marked with `FeatureSwitchDefinition` must properly return the AppContext switch value when defined: ```csharp // INCORRECT implementation [FeatureSwitchDefinition("System.Net.SocketsHttpHandler.Http3Support")] public static bool IsHttp3Supported => SomeDefaultLogic(); // CORRECT implementation - must use the AppContext switch value [FeatureSwitchDefinition("System.Net.SocketsHttpHandler.Http3Support")] public static bool IsHttp3Supported => AppContext.TryGetSwitch("System.Net.SocketsHttpHandler.Http3Support", out var ret) ? ret : SomeDefaultLogic(); ``` Consider dead code elimination implications when designing feature flags for AOT scenarios, as behavior differences may arise between `dotnet run` and `dotnet publish`. Avoid adding configuration switches preemptively - only introduce them when there's a demonstrated need from users. For platform-specific features, ensure configuration is properly respected across all supported environments.