diff --git a/src/Avalonia.Base/Data/Core/AvaloniaPropertyAccessorNode.cs b/src/Avalonia.Base/Data/Core/AvaloniaPropertyAccessorNode.cs
index 18e853722d..3484fb5e23 100644
--- a/src/Avalonia.Base/Data/Core/AvaloniaPropertyAccessorNode.cs
+++ b/src/Avalonia.Base/Data/Core/AvaloniaPropertyAccessorNode.cs
@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Avalonia.Data.Core
 {
-    public class AvaloniaPropertyAccessorNode : ExpressionNode, ISettableNode
+    public class AvaloniaPropertyAccessorNode : SettableNode
     {
         private readonly bool _enableValidation;
         private readonly AvaloniaProperty _property;
@@ -18,9 +18,9 @@ namespace Avalonia.Data.Core
 
         public override string Description => PropertyName;
         public string PropertyName { get; }
-        public Type PropertyType => _property.PropertyType;
+        public override Type PropertyType => _property.PropertyType;
 
-        public bool SetTargetValue(object value, BindingPriority priority)
+        protected override bool SetTargetValueCore(object value, BindingPriority priority)
         {
             try
             {
diff --git a/src/Avalonia.Base/Data/Core/IndexerExpressionNode.cs b/src/Avalonia.Base/Data/Core/IndexerExpressionNode.cs
index a14802a433..0b0d43a97d 100644
--- a/src/Avalonia.Base/Data/Core/IndexerExpressionNode.cs
+++ b/src/Avalonia.Base/Data/Core/IndexerExpressionNode.cs
@@ -34,7 +34,7 @@ namespace Avalonia.Data.Core
 
         public override string Description => expression.ToString();
 
-        public override bool SetTargetValue(object value, BindingPriority priority)
+        protected override bool SetTargetValueCore(object value, BindingPriority priority)
         {
             try
             {
diff --git a/src/Avalonia.Base/Data/Core/IndexerNodeBase.cs b/src/Avalonia.Base/Data/Core/IndexerNodeBase.cs
index 6dc7d61168..a43d119ebb 100644
--- a/src/Avalonia.Base/Data/Core/IndexerNodeBase.cs
+++ b/src/Avalonia.Base/Data/Core/IndexerNodeBase.cs
@@ -13,7 +13,7 @@ using Avalonia.Utilities;
 
 namespace Avalonia.Data.Core
 {
-    public abstract class IndexerNodeBase : ExpressionNode, ISettableNode
+    public abstract class IndexerNodeBase : SettableNode
     {
         protected override IObservable<object> StartListeningCore(WeakReference reference)
         {
@@ -41,10 +41,6 @@ namespace Avalonia.Data.Core
             return inputs.Merge().StartWith(GetValue(target));
         }
 
-        public abstract bool SetTargetValue(object value, BindingPriority priority);
-
-        public abstract Type PropertyType { get; }
-
         protected abstract object GetValue(object target);
 
         protected abstract int? TryGetFirstArgumentAsInt();
diff --git a/src/Avalonia.Base/Data/Core/SettableNode.cs b/src/Avalonia.Base/Data/Core/SettableNode.cs
index 092cdbe48f..e7c6ab766f 100644
--- a/src/Avalonia.Base/Data/Core/SettableNode.cs
+++ b/src/Avalonia.Base/Data/Core/SettableNode.cs
@@ -7,7 +7,7 @@ using System.Threading.Tasks;
 
 namespace Avalonia.Data.Core
 {
-    internal abstract class SettableNode : ExpressionNode
+    public abstract class SettableNode : ExpressionNode
     {
         public bool SetTargetValue(object value, BindingPriority priority)
         {
diff --git a/src/Markup/Avalonia.Markup/Markup/Parsers/Nodes/StringIndexerNode.cs b/src/Markup/Avalonia.Markup/Markup/Parsers/Nodes/StringIndexerNode.cs
index 01eb0a9b53..b3d0555f14 100644
--- a/src/Markup/Avalonia.Markup/Markup/Parsers/Nodes/StringIndexerNode.cs
+++ b/src/Markup/Avalonia.Markup/Markup/Parsers/Nodes/StringIndexerNode.cs
@@ -25,7 +25,7 @@ namespace Avalonia.Markup.Parsers.Nodes
 
         public override string Description => "[" + string.Join(",", Arguments) + "]";
 
-        public override bool SetTargetValue(object value, BindingPriority priority)
+        protected override bool SetTargetValueCore(object value, BindingPriority priority)
         {
             var typeInfo = Target.Target.GetType().GetTypeInfo();
             var list = Target.Target as IList;