diff --git a/docs/demo/src/WTA.Shared/Attributes/OneToOneAttribute.cs b/docs/demo/src/WTA.Shared/Attributes/OneToOneAttribute.cs
new file mode 100644
index 00000000..1c9a4bf5
--- /dev/null
+++ b/docs/demo/src/WTA.Shared/Attributes/OneToOneAttribute.cs
@@ -0,0 +1,14 @@
+namespace WTA.Shared.Attributes;
+
+[AttributeUsage(AttributeTargets.Property)]
+public class OneToOneAttribute<TEntity> : Attribute, ITypeAttribute
+{
+    public Type Type { get; set; } = null!;
+    public string? Property { get; }
+
+    public OneToOneAttribute(string? property = null)
+    {
+        this.Type = typeof(TEntity);
+        this.Property = property;
+    }
+}