diff --git a/DigitalData.Core.Tests/Mock/User.cs b/DigitalData.Core.Tests/Mock/User.cs
index c2e1b1a..ce8d780 100644
--- a/DigitalData.Core.Tests/Mock/User.cs
+++ b/DigitalData.Core.Tests/Mock/User.cs
@@ -1,12 +1,12 @@
 namespace DigitalData.Core.Tests.Mock;
 
-public class User
+public class User : UserBase
 {
     public required int Id { get; init; }
 
-    public required string FirstName { get; init; }
+    public override int GetHashCode() => HashCode.Combine(Id, FirstName, Email, Age);
 
-    public required string Email { get; init; }
-
-    public int Age { get; init; }
+    public override bool Equals(object? obj)
+        => (obj is User user && user.GetHashCode() == GetHashCode())
+        || (obj is UserBase userBase && userBase.GetHashCode() == base.GetHashCode());
 }
diff --git a/DigitalData.Core.Tests/Mock/UserBase.cs b/DigitalData.Core.Tests/Mock/UserBase.cs
new file mode 100644
index 0000000..ea8cc79
--- /dev/null
+++ b/DigitalData.Core.Tests/Mock/UserBase.cs
@@ -0,0 +1,14 @@
+namespace DigitalData.Core.Tests.Mock;
+
+public class UserBase
+{
+    public required string FirstName { get; init; }
+
+    public required string Email { get; init; }
+
+    public required int Age { get; init; }
+
+    public override int GetHashCode() => HashCode.Combine(FirstName, Email, Age);
+
+    public override bool Equals(object? obj) => obj is UserBase user && user.GetHashCode() == GetHashCode();
+}
diff --git a/DigitalData.Core.Tests/Mock/UserDto.cs b/DigitalData.Core.Tests/Mock/UserDto.cs
index f763db4..928b59c 100644
--- a/DigitalData.Core.Tests/Mock/UserDto.cs
+++ b/DigitalData.Core.Tests/Mock/UserDto.cs
@@ -1,10 +1,5 @@
 namespace DigitalData.Core.Tests.Mock;
 
-public class UserDto
+public class UserDto : UserBase
 {
-    public required string FirstName { get; init; }
-
-    public required string Email { get; init; }
-
-    public int Age { get; init; }
 }