diff --git a/UIX/Microsoft/Iris/Markup/AssemblyTypeSchema.cs b/UIX/Microsoft/Iris/Markup/AssemblyTypeSchema.cs
index 86bfe09..7c63ba2 100644
--- a/UIX/Microsoft/Iris/Markup/AssemblyTypeSchema.cs
+++ b/UIX/Microsoft/Iris/Markup/AssemblyTypeSchema.cs
@@ -12,7 +12,7 @@ using System.Reflection;
 
 namespace Microsoft.Iris.Markup
 {
-    internal class AssemblyTypeSchema : TypeSchema
+    internal class AssemblyTypeSchema : TypeSchema, ITypeSchemaWithInternalType
     {
         private Type _type;
         private TypeSchema _baseType;
diff --git a/UIX/Microsoft/Iris/Markup/ITypeSchemaWithInternalType.cs b/UIX/Microsoft/Iris/Markup/ITypeSchemaWithInternalType.cs
new file mode 100644
index 0000000..99b94e4
--- /dev/null
+++ b/UIX/Microsoft/Iris/Markup/ITypeSchemaWithInternalType.cs
@@ -0,0 +1,8 @@
+using System;
+
+namespace Microsoft.Iris.Markup;
+
+public interface ITypeSchemaWithInternalType
+{
+    Type InternalType { get; }
+}