diff --git a/Casks/mono-mdk-preview.rb b/Casks/mono-mdk-preview.rb
new file mode 100644
index 000000000..e753c371b
--- /dev/null
+++ b/Casks/mono-mdk-preview.rb
@@ -0,0 +1,13 @@
+cask 'mono-mdk-preview' do
+  version '4.3.0.2114'
+  sha256 :no_check # required as upstream package is updated in-place
+
+  url "http://download.xamarin.com/roslyn-preview/MonoFramework-MDK-#{version}.macos10.xamarin.universal.pkg"
+  name 'Mono'
+  homepage 'http://mono-project.com'
+  license :oss
+
+  pkg "MonoFramework-MDK-#{version}.macos10.xamarin.universal.pkg"
+
+  uninstall pkgutil: 'com.xamarin.mono-*'
+end
diff --git a/Casks/xamarin-studio-preview.rb b/Casks/xamarin-studio-preview.rb
new file mode 100644
index 000000000..4d7c7f3b9
--- /dev/null
+++ b/Casks/xamarin-studio-preview.rb
@@ -0,0 +1,13 @@
+cask 'xamarin-studio-preview' do
+  version '6.0.0.3668'
+  sha256 '1ed29cac15b64a6bce00f81f7898ac21c55d4c04b33372c0bf61a1d11d5ee389'
+
+  url "http://download.xamarin.com/roslyn-preview/XamarinStudio-#{version}.dmg"
+  appcast 'https://static.xamarin.com/installer_assets/v3/Mac/Universal/InstallationManifest.xml',
+          checkpoint: '855d95a330efdd9cc13cbaabc6e49dfcda111db3b16cbc6345e3a0d17e769972'
+  name 'Xamarin Studio Preview'
+  homepage 'https://xamarin.com/studio'
+  license :gpl
+
+  app 'Xamarin Studio.app'
+end