diff --git a/src/Microsoft.AspNet.Mvc.Razor/DependencyInjection/MvcRazorMvcCoreBuilderExtensions.cs b/src/Microsoft.AspNet.Mvc.Razor/DependencyInjection/MvcRazorMvcCoreBuilderExtensions.cs
index 362d4f2507..dc6e2d04a3 100644
--- a/src/Microsoft.AspNet.Mvc.Razor/DependencyInjection/MvcRazorMvcCoreBuilderExtensions.cs
+++ b/src/Microsoft.AspNet.Mvc.Razor/DependencyInjection/MvcRazorMvcCoreBuilderExtensions.cs
@@ -123,7 +123,7 @@ namespace Microsoft.Extensions.DependencyInjection
         {
             if (CompilationServices.Default != null)
             {
-                services.TryAdd(ServiceDescriptor.Instance(CompilationServices.Default.LibraryExporter));
+                services.TryAddSingleton(CompilationServices.Default.LibraryExporter);
             }
 
             services.TryAddEnumerable(
@@ -165,7 +165,7 @@ namespace Microsoft.Extensions.DependencyInjection
 
             if (PlatformServices.Default?.AssemblyLoadContextAccessor != null)
             {
-                services.TryAdd(ServiceDescriptor.Instance(PlatformServices.Default.AssemblyLoadContextAccessor));
+                services.TryAddSingleton(PlatformServices.Default.AssemblyLoadContextAccessor);
             }
         }
     }
diff --git a/test/Microsoft.AspNet.Mvc.Localization.Test/Internal/MvcLocalizationServiceCollectionExtensionsTest.cs b/test/Microsoft.AspNet.Mvc.Localization.Test/Internal/MvcLocalizationServiceCollectionExtensionsTest.cs
index d6a7c7c4e4..1eef28a4af 100644
--- a/test/Microsoft.AspNet.Mvc.Localization.Test/Internal/MvcLocalizationServiceCollectionExtensionsTest.cs
+++ b/test/Microsoft.AspNet.Mvc.Localization.Test/Internal/MvcLocalizationServiceCollectionExtensionsTest.cs
@@ -67,7 +67,7 @@ namespace Microsoft.AspNet.Mvc.Localization.Internal
             collection.Add(ServiceDescriptor.Singleton(typeof(IHtmlLocalizerFactory), typeof(TestHtmlLocalizerFactory)));
             collection.Add(ServiceDescriptor.Transient(typeof(IHtmlLocalizer<>), typeof(TestHtmlLocalizer<>)));
             collection.Add(ServiceDescriptor.Transient(typeof(IViewLocalizer), typeof(TestViewLocalizer)));
-            collection.Add(ServiceDescriptor.Instance(typeof(HtmlEncoder), testEncoder));
+            collection.Add(ServiceDescriptor.Singleton(typeof(HtmlEncoder), testEncoder));
 
             MvcLocalizationServices.AddMvcLocalizationServices(
                 collection,
@@ -125,7 +125,7 @@ namespace Microsoft.AspNet.Mvc.Localization.Internal
 
             collection.Add(ServiceDescriptor.Transient(typeof(IHtmlLocalizer<>), typeof(TestHtmlLocalizer<>)));
             collection.Add(ServiceDescriptor.Transient(typeof(IHtmlLocalizer), typeof(TestViewLocalizer)));
-            collection.Add(ServiceDescriptor.Instance(typeof(HtmlEncoder), typeof(HtmlTestEncoder)));
+            collection.Add(ServiceDescriptor.Singleton(typeof(HtmlEncoder), typeof(HtmlTestEncoder)));
 
             // Assert
             Assert.Collection(collection,