diff --git a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeBasicWriter.cs b/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeBasicWriter.cs
index 5dbb52af7b..097bb47105 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeBasicWriter.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeBasicWriter.cs
@@ -2,7 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Linq;
+using Microsoft.AspNetCore.Razor.Language.Extensions;
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
 namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
diff --git a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/AddPreallocatedTagHelperHtmlAttributeIntermediateNode.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/AddPreallocatedTagHelperHtmlAttributeIntermediateNode.cs
similarity index 93%
rename from src/Microsoft.AspNetCore.Razor.Language/Intermediate/AddPreallocatedTagHelperHtmlAttributeIntermediateNode.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/AddPreallocatedTagHelperHtmlAttributeIntermediateNode.cs
index 6c50ee7026..fc207b827b 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/AddPreallocatedTagHelperHtmlAttributeIntermediateNode.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/AddPreallocatedTagHelperHtmlAttributeIntermediateNode.cs
@@ -3,8 +3,9 @@
 
 using System;
 using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.Intermediate
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal sealed class AddPreallocatedTagHelperHtmlAttributeIntermediateNode : ExtensionIntermediateNode
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/DeclarePreallocatedTagHelperAttributeIntermediateNode.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DeclarePreallocatedTagHelperAttributeIntermediateNode.cs
similarity index 94%
rename from src/Microsoft.AspNetCore.Razor.Language/Intermediate/DeclarePreallocatedTagHelperAttributeIntermediateNode.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/DeclarePreallocatedTagHelperAttributeIntermediateNode.cs
index e421a63f7a..6423f47b25 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/DeclarePreallocatedTagHelperAttributeIntermediateNode.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DeclarePreallocatedTagHelperAttributeIntermediateNode.cs
@@ -3,8 +3,9 @@
 
 using System;
 using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.Intermediate
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal sealed class DeclarePreallocatedTagHelperAttributeIntermediateNode : ExtensionIntermediateNode
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode.cs
similarity index 94%
rename from src/Microsoft.AspNetCore.Razor.Language/Intermediate/DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode.cs
index 0abab80389..54e30cb8c7 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode.cs
@@ -3,8 +3,9 @@
 
 using System;
 using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.Intermediate
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal sealed class DeclarePreallocatedTagHelperHtmlAttributeIntermediateNode : ExtensionIntermediateNode
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/DesignTimeDirectiveIntermediateNode.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectiveIntermediateNode.cs
similarity index 92%
rename from src/Microsoft.AspNetCore.Razor.Language/Intermediate/DesignTimeDirectiveIntermediateNode.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectiveIntermediateNode.cs
index e295a6a7d8..bc038d5ad3 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/DesignTimeDirectiveIntermediateNode.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectiveIntermediateNode.cs
@@ -3,8 +3,9 @@
 
 using System;
 using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.Intermediate
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal sealed class DesignTimeDirectiveIntermediateNode : ExtensionIntermediateNode
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/DesignTimeDirectivePass.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectivePass.cs
similarity index 97%
rename from src/Microsoft.AspNetCore.Razor.Language/DesignTimeDirectivePass.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectivePass.cs
index 1ccd9c891d..0a69d2d12f 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/DesignTimeDirectivePass.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectivePass.cs
@@ -3,7 +3,7 @@
 
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal class DesignTimeDirectivePass : IntermediateNodePassBase, IRazorDirectiveClassifierPass
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeDirectiveTargetExtension.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectiveTargetExtension.cs
similarity index 97%
rename from src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeDirectiveTargetExtension.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectiveTargetExtension.cs
index 97db440718..0536246d97 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/DesignTimeDirectiveTargetExtension.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/DesignTimeDirectiveTargetExtension.cs
@@ -2,9 +2,10 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal class DesignTimeDirectiveTargetExtension : IDesignTimeDirectiveTargetExtension
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/IDesignTimeDirectiveTargetExtension.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/IDesignTimeDirectiveTargetExtension.cs
similarity index 79%
rename from src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/IDesignTimeDirectiveTargetExtension.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/IDesignTimeDirectiveTargetExtension.cs
index b67d7df6fd..67aa5ea482 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/IDesignTimeDirectiveTargetExtension.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/IDesignTimeDirectiveTargetExtension.cs
@@ -1,9 +1,10 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal interface IDesignTimeDirectiveTargetExtension : ICodeTargetExtension
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/IPreallocatedAttributeTargetExtension.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/IPreallocatedAttributeTargetExtension.cs
similarity index 83%
rename from src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/IPreallocatedAttributeTargetExtension.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/IPreallocatedAttributeTargetExtension.cs
index dcf3bf8072..85cd26fce0 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/IPreallocatedAttributeTargetExtension.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/IPreallocatedAttributeTargetExtension.cs
@@ -1,9 +1,10 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using Microsoft.AspNetCore.Razor.Language.Intermediate;
+using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Extensions;
 
-namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal interface IPreallocatedAttributeTargetExtension : ICodeTargetExtension
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/PreallocatedAttributeTargetExtension.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/PreallocatedAttributeTargetExtension.cs
similarity index 97%
rename from src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/PreallocatedAttributeTargetExtension.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/PreallocatedAttributeTargetExtension.cs
index e101707eac..85725b1f06 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/CodeGeneration/PreallocatedAttributeTargetExtension.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/PreallocatedAttributeTargetExtension.cs
@@ -2,10 +2,9 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using Microsoft.AspNetCore.Razor.Language.Intermediate;
-using Microsoft.AspNetCore.Razor.Language.Legacy;
+using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
 
-namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal class PreallocatedAttributeTargetExtension : IPreallocatedAttributeTargetExtension
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/RazorPreallocatedTagHelperAttributeOptimizationPass.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/PreallocatedTagHelperAttributeOptimizationPass.cs
similarity index 97%
rename from src/Microsoft.AspNetCore.Razor.Language/RazorPreallocatedTagHelperAttributeOptimizationPass.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/PreallocatedTagHelperAttributeOptimizationPass.cs
index 0cc9261bba..8171e9a494 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/RazorPreallocatedTagHelperAttributeOptimizationPass.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/PreallocatedTagHelperAttributeOptimizationPass.cs
@@ -6,9 +6,9 @@ using System.Linq;
 using System.Text;
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
-    internal class RazorPreallocatedTagHelperAttributeOptimizationPass : IntermediateNodePassBase, IRazorOptimizationPass
+    internal class PreallocatedTagHelperAttributeOptimizationPass : IntermediateNodePassBase, IRazorOptimizationPass
     {
         public override int Order => DefaultFeatureOrder;
 
diff --git a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/SetPreallocatedTagHelperPropertyIntermediateNode.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/SetPreallocatedTagHelperPropertyIntermediateNode.cs
similarity index 94%
rename from src/Microsoft.AspNetCore.Razor.Language/Intermediate/SetPreallocatedTagHelperPropertyIntermediateNode.cs
rename to src/Microsoft.AspNetCore.Razor.Language/Extensions/SetPreallocatedTagHelperPropertyIntermediateNode.cs
index caa1d6a760..7660d948ba 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Intermediate/SetPreallocatedTagHelperPropertyIntermediateNode.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/SetPreallocatedTagHelperPropertyIntermediateNode.cs
@@ -3,8 +3,9 @@
 
 using System;
 using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
 
-namespace Microsoft.AspNetCore.Razor.Language.Intermediate
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     internal sealed class SetPreallocatedTagHelperPropertyIntermediateNode : ExtensionIntermediateNode
     {
diff --git a/src/Microsoft.AspNetCore.Razor.Language/RazorEngine.cs b/src/Microsoft.AspNetCore.Razor.Language/RazorEngine.cs
index e9fa398537..3095964eb6 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/RazorEngine.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/RazorEngine.cs
@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Extensions;
 
 namespace Microsoft.AspNetCore.Razor.Language
 {
@@ -103,7 +104,7 @@ namespace Microsoft.AspNetCore.Razor.Language
 
         internal static void AddRuntimeDefaults(IRazorEngineBuilder builder)
         {
-            builder.Features.Add(new RazorPreallocatedTagHelperAttributeOptimizationPass());
+            builder.Features.Add(new PreallocatedTagHelperAttributeOptimizationPass());
         }
 
         internal static void AddDesignTimeDefaults(IRazorEngineBuilder builder)
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/CodeGeneration/DesignTimeDirectiveTargetExtensionTest.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/DesignTimeDirectiveTargetExtensionTest.cs
similarity index 98%
rename from test/Microsoft.AspNetCore.Razor.Language.Test/CodeGeneration/DesignTimeDirectiveTargetExtensionTest.cs
rename to test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/DesignTimeDirectiveTargetExtensionTest.cs
index 7f890e3a95..3cf963a604 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/CodeGeneration/DesignTimeDirectiveTargetExtensionTest.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/DesignTimeDirectiveTargetExtensionTest.cs
@@ -2,10 +2,10 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
-using Microsoft.AspNetCore.Razor.Language.Legacy;
+using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
 using Xunit;
 
-namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     public class DesignTimeDirectiveTargetExtensionTest
     {
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/CodeGeneration/PreallocatedAttributeTargetExtensionTest.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/PreallocatedAttributeTargetExtensionTest.cs
similarity index 97%
rename from test/Microsoft.AspNetCore.Razor.Language.Test/CodeGeneration/PreallocatedAttributeTargetExtensionTest.cs
rename to test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/PreallocatedAttributeTargetExtensionTest.cs
index 8b2e842f0d..d6e1c28815 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/CodeGeneration/PreallocatedAttributeTargetExtensionTest.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/PreallocatedAttributeTargetExtensionTest.cs
@@ -1,11 +1,10 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using Microsoft.AspNetCore.Razor.Language.Intermediate;
-using Microsoft.AspNetCore.Razor.Language.Legacy;
+using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
 using Xunit;
 
-namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
+namespace Microsoft.AspNetCore.Razor.Language.Extensions
 {
     public class PreallocatedAttributeTargetExtensionTest
     {
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/RazorEngineTest.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/RazorEngineTest.cs
index edeb0ca2d2..555a68d081 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/RazorEngineTest.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/RazorEngineTest.cs
@@ -3,7 +3,7 @@
 
 using System.Collections.Generic;
 using System.Linq;
-using Microsoft.AspNetCore.Razor.Language.CodeGeneration;
+using Microsoft.AspNetCore.Razor.Language.Extensions;
 using Moq;
 using Xunit;
 
@@ -152,7 +152,7 @@ namespace Microsoft.AspNetCore.Razor.Language
                 feature => Assert.IsType<DefaultDocumentClassifierPass>(feature),
                 feature => Assert.IsType<DirectiveRemovalOptimizationPass>(feature),
                 feature => Assert.IsType<DefaultDocumentClassifierPassFeature>(feature),
-                feature => Assert.IsType<RazorPreallocatedTagHelperAttributeOptimizationPass>(feature));
+                feature => Assert.IsType<PreallocatedTagHelperAttributeOptimizationPass>(feature));
         }
 
         private static void AssertDefaultRuntimePhases(IReadOnlyList<IRazorEnginePhase> phases)
diff --git a/test/Microsoft.AspNetCore.Razor.Test.Common/Langauge/Intermediate/IntermediateNodeAssert.cs b/test/Microsoft.AspNetCore.Razor.Test.Common/Langauge/Intermediate/IntermediateNodeAssert.cs
index f121ad464b..3b23141932 100644
--- a/test/Microsoft.AspNetCore.Razor.Test.Common/Langauge/Intermediate/IntermediateNodeAssert.cs
+++ b/test/Microsoft.AspNetCore.Razor.Test.Common/Langauge/Intermediate/IntermediateNodeAssert.cs
@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Text;
+using Microsoft.AspNetCore.Razor.Language.Extensions;
 using Microsoft.AspNetCore.Razor.Language.Legacy;
 using Xunit;
 using Xunit.Sdk;