# Microsoft.Extensions.Configuration

``` diff
 namespace Microsoft.Extensions.Configuration {
     public static class KeyPerFileConfigurationBuilderExtensions {
+        public static IConfigurationBuilder AddKeyPerFile(this IConfigurationBuilder builder, string directoryPath);
+        public static IConfigurationBuilder AddKeyPerFile(this IConfigurationBuilder builder, string directoryPath, bool optional, bool reloadOnChange);
     }
 }
```

