diff --git a/testapps/ApplicationWithConfigureMvc/RazorRewriter.cs b/testapps/ApplicationWithConfigureMvc/RazorRewriter.cs
index 5c956c8..4c0e42d 100644
--- a/testapps/ApplicationWithConfigureMvc/RazorRewriter.cs
+++ b/testapps/ApplicationWithConfigureMvc/RazorRewriter.cs
@@ -1,4 +1,5 @@
-using Microsoft.CodeAnalysis;
+using System;
+using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;