diff --git a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt
index 06a999b722..debb4a1b51 100644
--- a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt
+++ b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt
@@ -269,7 +269,7 @@ namespace ReactiveUI
         System.IDisposable BindTo<TValue, TTarget, TTValue>(System.IObservable<TValue> observedChange, TTarget? target, System.Linq.Expressions.Expression<System.Func<TTarget, TTValue?>> propertyExpression, object? conversionHint, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
             where TTarget :  class
         ;
-        ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp?, TOut> selector)
+        ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp, TOut> selector)
             where TViewModel :  class
             where TView :  class, ReactiveUI.IViewFor
         ;
@@ -544,7 +544,7 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor { }
         public System.IDisposable BindTo<TValue, TTarget, TTValue>(System.IObservable<TValue> observedChange, TTarget? target, System.Linq.Expressions.Expression<System.Func<TTarget, TTValue?>> propertyExpression, object? conversionHint = null, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
             where TTarget :  class { }
-        public ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp?, TOut> selector)
+        public ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp, TOut> selector)
             where TViewModel :  class
             where TView :  class, ReactiveUI.IViewFor { }
         public ReactiveUI.IReactiveBinding<TView, TVProp> OneWayBind<TViewModel, TView, TVMProp, TVProp>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TVMProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TVProp>> viewProperty, object? conversionHint = null, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
diff --git a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt
index 16eb4deb16..673a2eb0fd 100644
--- a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt
+++ b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt
@@ -264,7 +264,7 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor;
         System.IDisposable BindTo<TValue, TTarget, TTValue>(System.IObservable<TValue> observedChange, TTarget? target, System.Linq.Expressions.Expression<System.Func<TTarget, TTValue?>> propertyExpression, object? conversionHint, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
             where TTarget :  class;
-        ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp?, TOut> selector)
+        ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp, TOut> selector)
             where TViewModel :  class
             where TView :  class, ReactiveUI.IViewFor;
         ReactiveUI.IReactiveBinding<TView, TVProp> OneWayBind<TViewModel, TView, TVMProp, TVProp>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TVMProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TVProp>> viewProperty, object? conversionHint, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
@@ -537,7 +537,7 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor { }
         public System.IDisposable BindTo<TValue, TTarget, TTValue>(System.IObservable<TValue> observedChange, TTarget? target, System.Linq.Expressions.Expression<System.Func<TTarget, TTValue?>> propertyExpression, object? conversionHint = null, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
             where TTarget :  class { }
-        public ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp?, TOut> selector)
+        public ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp, TOut> selector)
             where TViewModel :  class
             where TView :  class, ReactiveUI.IViewFor { }
         public ReactiveUI.IReactiveBinding<TView, TVProp> OneWayBind<TViewModel, TView, TVMProp, TVProp>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TVMProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TVProp>> viewProperty, object? conversionHint = null, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
diff --git a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt
index 5064a6977d..293a03b4c0 100644
--- a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt
+++ b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt
@@ -264,7 +264,7 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor;
         System.IDisposable BindTo<TValue, TTarget, TTValue>(System.IObservable<TValue> observedChange, TTarget? target, System.Linq.Expressions.Expression<System.Func<TTarget, TTValue?>> propertyExpression, object? conversionHint, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
             where TTarget :  class;
-        ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp?, TOut> selector)
+        ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp, TOut> selector)
             where TViewModel :  class
             where TView :  class, ReactiveUI.IViewFor;
         ReactiveUI.IReactiveBinding<TView, TVProp> OneWayBind<TViewModel, TView, TVMProp, TVProp>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TVMProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TVProp>> viewProperty, object? conversionHint, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
@@ -537,7 +537,7 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor { }
         public System.IDisposable BindTo<TValue, TTarget, TTValue>(System.IObservable<TValue> observedChange, TTarget? target, System.Linq.Expressions.Expression<System.Func<TTarget, TTValue?>> propertyExpression, object? conversionHint = null, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
             where TTarget :  class { }
-        public ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp?, TOut> selector)
+        public ReactiveUI.IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TOut>> viewProperty, System.Func<TProp, TOut> selector)
             where TViewModel :  class
             where TView :  class, ReactiveUI.IViewFor { }
         public ReactiveUI.IReactiveBinding<TView, TVProp> OneWayBind<TViewModel, TView, TVMProp, TVProp>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TVMProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TVProp>> viewProperty, object? conversionHint = null, ReactiveUI.IBindingTypeConverter? vmToViewConverterOverride = null)
diff --git a/src/ReactiveUI.Uno/ReactiveUI.Uno.csproj b/src/ReactiveUI.Uno/ReactiveUI.Uno.csproj
index a8dfdd3fa0..a3b2feb072 100644
--- a/src/ReactiveUI.Uno/ReactiveUI.Uno.csproj
+++ b/src/ReactiveUI.Uno/ReactiveUI.Uno.csproj
@@ -22,7 +22,7 @@
   </ItemGroup>
 
   <ItemGroup Condition=" !$(TargetFramework.StartsWith('uap')) ">
-    <PackageReference Include="Uno.UI" Version="3.10.0-dev.414" />
+    <PackageReference Include="Uno.UI" Version="3.10.0-dev.591" />
   </ItemGroup>
 
   <ItemGroup Condition=" $(TargetFramework.StartsWith('netstandard')) ">
diff --git a/src/ReactiveUI.WinUI/ReactiveUI.WinUI.csproj b/src/ReactiveUI.WinUI/ReactiveUI.WinUI.csproj
index 039ddf1eab..3805c58e16 100644
--- a/src/ReactiveUI.WinUI/ReactiveUI.WinUI.csproj
+++ b/src/ReactiveUI.WinUI/ReactiveUI.WinUI.csproj
@@ -11,7 +11,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.ProjectReunion" Version="0.8.2" />
+    <PackageReference Include="Microsoft.ProjectReunion" Version="0.8.3" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/ReactiveUI/Bindings/Property/IPropertyBinderImplementation.cs b/src/ReactiveUI/Bindings/Property/IPropertyBinderImplementation.cs
index d8bec8e6a6..3873174ee2 100644
--- a/src/ReactiveUI/Bindings/Property/IPropertyBinderImplementation.cs
+++ b/src/ReactiveUI/Bindings/Property/IPropertyBinderImplementation.cs
@@ -196,7 +196,7 @@ IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(
             TView view,
             Expression<Func<TViewModel, TProp?>> vmProperty,
             Expression<Func<TView, TOut>> viewProperty,
-            Func<TProp?, TOut> selector)
+            Func<TProp, TOut> selector)
             where TViewModel : class
             where TView : class, IViewFor;
 
diff --git a/src/ReactiveUI/Bindings/Property/PropertyBinderImplementation.cs b/src/ReactiveUI/Bindings/Property/PropertyBinderImplementation.cs
index 7f5a7d21c5..39d7e0a6e3 100644
--- a/src/ReactiveUI/Bindings/Property/PropertyBinderImplementation.cs
+++ b/src/ReactiveUI/Bindings/Property/PropertyBinderImplementation.cs
@@ -186,7 +186,7 @@ public IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(
             TView view,
             Expression<Func<TViewModel, TProp?>> vmProperty,
             Expression<Func<TView, TOut>> viewProperty,
-            Func<TProp?, TOut> selector)
+            Func<TProp, TOut> selector)
             where TViewModel : class
             where TView : class, IViewFor
         {
@@ -208,7 +208,7 @@ public IReactiveBinding<TView, TOut> OneWayBind<TViewModel, TView, TProp, TOut>(
                 return new ReactiveBinding<TView, TOut>(view, viewExpression, vmExpression, Observable.Empty<TOut>(), BindingDirection.OneWay, Disposable.Empty);
             }
 
-            var source = Reflection.ViewModelWhenAnyValue(viewModel, view, vmExpression).Cast<TProp?>().Select(selector);
+            var source = Reflection.ViewModelWhenAnyValue(viewModel, view, vmExpression).Cast<TProp>().Select(selector);
 
             var (disposable, obs) = BindToDirect<TView, TOut, TOut>(source, view, viewExpression);