diff --git a/src/Snapshooter/Helpers/ObjectWrapperRemover.cs b/src/Snapshooter/Helpers/ObjectWrapperRemover.cs
index 25ad33c..f5c05f4 100644
--- a/src/Snapshooter/Helpers/ObjectWrapperRemover.cs
+++ b/src/Snapshooter/Helpers/ObjectWrapperRemover.cs
@@ -5,7 +5,7 @@ namespace Snapshooter
 {
     public static class ObjectWrapperRemover
     {
-        public static object RemoveUnwantedWrappers(this object objectToRemoveWrappers)
+        internal static object RemoveUnwantedWrappers(this object objectToRemoveWrappers)
         {
             if (objectToRemoveWrappers == null)
             {
diff --git a/src/Snapshooter/InternalsVisibleTo.cs b/src/Snapshooter/InternalsVisibleTo.cs
new file mode 100644
index 0000000..ae2a2c2
--- /dev/null
+++ b/src/Snapshooter/InternalsVisibleTo.cs
@@ -0,0 +1,4 @@
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("Snapshooter.NUnit")]
+[assembly: InternalsVisibleTo("Snapshooter.XUnit")]