diff --git a/.travis.yml b/.travis.yml
index d80d24f32c..b0c0c807cb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,6 +11,8 @@ mono:
   - 5.2.0
 dotnet: 2.1.200
 script:
+  - sudo apt-get update
+  - sudo apt-get install castxml
   - ./build.sh --target "Travis" --configuration "Release"
 notifications:
   email: false
diff --git a/build.cake b/build.cake
index 000cbb1784..d653e9da58 100644
--- a/build.cake
+++ b/build.cake
@@ -3,8 +3,8 @@
 ///////////////////////////////////////////////////////////////////////////////
 
 #addin "nuget:?package=NuGet.Core&version=2.14.0"
-#tool "nuget:?package=NuGet.CommandLine&version=4.3.0"
-#tool "nuget:?package=JetBrains.ReSharper.CommandLineTools&version=2017.1.20170613.162720"
+#tool "nuget:?package=NuGet.CommandLine&version=4.7.1"
+#tool "nuget:?package=JetBrains.ReSharper.CommandLineTools&version=2018.2.3"
 
 ///////////////////////////////////////////////////////////////////////////////
 // TOOLS
diff --git a/src/Markup/Avalonia.Markup/Data/MultiBinding.cs b/src/Markup/Avalonia.Markup/Data/MultiBinding.cs
index 4c47ef32e0..4921b7c9d7 100644
--- a/src/Markup/Avalonia.Markup/Data/MultiBinding.cs
+++ b/src/Markup/Avalonia.Markup/Data/MultiBinding.cs
@@ -61,7 +61,7 @@ namespace Avalonia.Data
 
             var targetType = targetProperty?.PropertyType ?? typeof(object);
             var children = Bindings.Select(x => x.Initiate(target, null));
-            var input = children.Select(x => x.Subject).CombineLatest().Select(x => ConvertValue(x, targetType));
+            var input = children.Select(x => x.Observable).CombineLatest().Select(x => ConvertValue(x, targetType));
             var mode = Mode == BindingMode.Default ?
                 targetProperty?.GetMetadata(target.GetType()).DefaultBindingMode : Mode;
 
diff --git a/tests/Avalonia.Markup.UnitTests/Data/MultiBindingTests.cs b/tests/Avalonia.Markup.UnitTests/Data/MultiBindingTests.cs
index fb23a38cce..78c538d99d 100644
--- a/tests/Avalonia.Markup.UnitTests/Data/MultiBindingTests.cs
+++ b/tests/Avalonia.Markup.UnitTests/Data/MultiBindingTests.cs
@@ -41,6 +41,37 @@ namespace Avalonia.Markup.UnitTests.Data
             Assert.Equal("1,2,3", result);
         }
 
+        [Fact]
+        public async Task Nested_MultiBinding_Should_Be_Set_Up()
+        {
+            var source = new { A = 1, B = 2, C = 3 };
+            var binding = new MultiBinding
+            {
+                Converter = new ConcatConverter(),
+                Bindings =
+                {
+                    new Binding { Path = "A" },
+                    new MultiBinding
+                    {
+                        Converter = new ConcatConverter(),
+                        Bindings =
+                        {
+                            new Binding { Path = "B"},
+                            new Binding { Path = "C"}
+                        }
+                    }
+                }
+            };
+
+            var target = new Mock<IAvaloniaObject>().As<IControl>();
+            target.Setup(x => x.GetValue(Control.DataContextProperty)).Returns(source);
+
+            var observable = binding.Initiate(target.Object, null).Observable;
+            var result = await observable.Take(1);
+
+            Assert.Equal("1,2,3", result);
+        }
+
         [Fact]
         public void Should_Return_FallbackValue_When_Converter_Returns_UnsetValue()
         {
diff --git a/tools/packages.config b/tools/packages.config
index 3c65df896f..05018882e8 100644
--- a/tools/packages.config
+++ b/tools/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-    <package id="Cake" version="0.28.0" />
+    <package id="Cake" version="0.30.0" />
 </packages>