diff --git a/src/Avalonia.Base/Animation/Easings/IEasing.cs b/src/Avalonia.Base/Animation/Easings/IEasing.cs
index 9c9c7b3a99..804c7b7912 100644
--- a/src/Avalonia.Base/Animation/Easings/IEasing.cs
+++ b/src/Avalonia.Base/Animation/Easings/IEasing.cs
@@ -1,8 +1,11 @@
+using Avalonia.Metadata;
+
 namespace Avalonia.Animation.Easings
 {
     /// <summary>
     /// Defines the interface for easing classes.
     /// </summary>
+    [NotClientImplementable]
     public interface IEasing
     {
         /// <summary>