diff --git a/src/Microsoft.AspNetCore.Razor.Language/Extensions/SectionTargetExtension.cs b/src/Microsoft.AspNetCore.Razor.Language/Extensions/SectionTargetExtension.cs
index e99c1598f3..ba1f637ad6 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Extensions/SectionTargetExtension.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Extensions/SectionTargetExtension.cs
@@ -22,9 +22,19 @@ namespace Microsoft.AspNetCore.Razor.Language.Extensions
                 .Write(node.SectionName)
                 .Write("\", ");
 
-            using (context.CodeWriter.BuildAsyncLambda(DefaultWriterName))
+            if (context.Options.DesignTime)
             {
-                context.RenderChildren(node);
+                using (context.CodeWriter.BuildAsyncLambda(DefaultWriterName))
+                {
+                    context.RenderChildren(node);
+                }
+            }
+            else
+            {
+                using (context.CodeWriter.BuildAsyncLambda())
+                {
+                    context.RenderChildren(node);
+                }
             }
 
             context.CodeWriter.WriteEndMethodInvocation(endLine: true);
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs
index 95aa1a96a8..ba56f04308 100644
--- a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs
@@ -51,7 +51,7 @@ namespace AspNetCore
             BeginContext(117, 26, true);
             WriteLiteral("\r\n<div>Some body</div>\r\n\r\n");
             EndContext();
-            DefineSection("Section1", async(__razor_section_writer) => {
+            DefineSection("Section1", async() => {
                 BeginContext(162, 43, true);
                 WriteLiteral("\r\n    <div>This is in Section 1</div>\r\n    ");
                 EndContext();
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/SectionTargetExtensionTest.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/SectionTargetExtensionTest.cs
index bfeb71ffb7..16288b3117 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/SectionTargetExtensionTest.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/Extensions/SectionTargetExtensionTest.cs
@@ -33,7 +33,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Extensions
             extension.WriteSection(context, node);
 
             // Assert
-            var expected = @"CreateSection(""MySection"", async(__razor_section_writer) => {
+            var expected = @"CreateSection(""MySection"", async() => {
     Render Children
 }
 );
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs
index 179aa5c3d8..128b60701f 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections_Runtime.codegen.cs
@@ -16,7 +16,7 @@ namespace Microsoft.AspNetCore.Razor.Language.IntegrationTests.TestFiles
 #line default
 #line hidden
             WriteLiteral("\r\n<div>This is in the Body>\r\n\r\n");
-            DefineSection("Section2", async(__razor_section_writer) => {
+            DefineSection("Section2", async() => {
                 WriteLiteral("\r\n    <div");
                 BeginWriteAttribute("class", " class=\"", 109, "\"", 128, 2);
                 WriteAttributeValue("", 117, "some", 117, 4, true);
@@ -30,12 +30,12 @@ WriteAttributeValue(" ", 121, thing, 122, 6, false);
             }
             );
             WriteLiteral("\r\n");
-            DefineSection("Section1", async(__razor_section_writer) => {
+            DefineSection("Section1", async() => {
                 WriteLiteral("\r\n    <div>This is in Section 1</div>\r\n");
             }
             );
             WriteLiteral("\r\n");
-            DefineSection("NestedDelegates", async(__razor_section_writer) => {
+            DefineSection("NestedDelegates", async() => {
                 WriteLiteral("\r\n");
 #line 16 "TestFiles/IntegrationTests/CodeGenerationIntegrationTest/Sections.cshtml"
        Func<dynamic, object> f = 
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/StringLiterals_Runtime.codegen.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/StringLiterals_Runtime.codegen.cs
index e3770e0570..ba174de703 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/StringLiterals_Runtime.codegen.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/StringLiterals_Runtime.codegen.cs
@@ -96,7 +96,7 @@ namespace Microsoft.AspNetCore.Razor.Language.IntegrationTests.TestFiles
 <p>This is line 84</p><br>
 
 ");
-            DefineSection("WriteLiteralsToInHere", async(__razor_section_writer) => {
+            DefineSection("WriteLiteralsToInHere", async() => {
                 WriteLiteral(@"
     <p>This is line 1 nested</p>
     <p>This is line 2 nested</p>
@@ -222,7 +222,7 @@ namespace Microsoft.AspNetCore.Razor.Language.IntegrationTests.TestFiles
 <p>This is line 42</p>
 <p>This is line 43</p>hi!");
             WriteLiteral("\r\n");
-            DefineSection("WriteLiteralsToInHereAlso", async(__razor_section_writer) => {
+            DefineSection("WriteLiteralsToInHereAlso", async() => {
                 WriteLiteral(@"
     <p>This is line 1 nested</p>
     <p>This is line 2 nested</p>
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/TagHelpersInSection_Runtime.codegen.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/TagHelpersInSection_Runtime.codegen.cs
index d8924cbaab..1d3fbf2f83 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/TagHelpersInSection_Runtime.codegen.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/TagHelpersInSection_Runtime.codegen.cs
@@ -37,7 +37,7 @@ namespace Microsoft.AspNetCore.Razor.Language.IntegrationTests.TestFiles
 #line default
 #line hidden
             WriteLiteral("\r\n");
-            DefineSection("MySection", async(__razor_section_writer) => {
+            DefineSection("MySection", async() => {
                 WriteLiteral("\r\n    <div>\r\n        ");
                 __tagHelperExecutionContext = __tagHelperScopeManager.Begin("mytaghelper", global::Microsoft.AspNetCore.Razor.TagHelpers.TagMode.StartTagAndEndTag, "test", async() => {
                     WriteLiteral("\r\n            In None ContentBehavior.\r\n            ");