diff --git a/.travis.yml b/.travis.yml
index 2950150f..cc3ced7c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,9 @@
 language: csharp
 
 sudo: false  # use the new container-based Travis infrastructure
+os:
+  - osx
+  - linux
 install:
   - curl -sS http://storage.bos.xamarin.com/bot-provisioning/PortableReferenceAssemblies-2014-04-14.zip > /tmp/pcl-assemblies.zip
   - unzip /tmp/pcl-assemblies.zip -d /tmp/pcl-assemblies && mv /tmp/pcl-assemblies/PortableReferenceAssemblies-2014-04-14 /tmp/pcl-assemblies/.NETPortable
diff --git a/Octokit.Tests/Octokit.Tests-Portable.csproj b/Octokit.Tests/Octokit.Tests-Portable.csproj
index 0362b293..5fb37353 100644
--- a/Octokit.Tests/Octokit.Tests-Portable.csproj
+++ b/Octokit.Tests/Octokit.Tests-Portable.csproj
@@ -36,27 +36,33 @@
     <NoWarn>4014, 1998</NoWarn>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="NSubstitute, Version=1.8.0.0, Culture=neutral, PublicKeyToken=92dd2e9066daa5ca, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>../packages/NSubstitute.1.8.0.0/lib/net40/NSubstitute.dll</HintPath>
-    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="Microsoft.CSharp" />
-    <Reference Include="System.Net.Http" />
-    <Reference Include="System.XML" />
+    <Reference Include="System.Net.Http">
+      <Private>True</Private>
+    </Reference>
     <Reference Include="System.Xml.Linq" />
-    <Reference Include="xunit.abstractions, Version=2.0.0.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c, processorArchitecture=MSIL">
+    <Reference Include="NSubstitute">
+      <HintPath>..\packages\NSubstitute.1.8.0.0\lib\net40\NSubstitute.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Xml" />
+    <Reference Include="xunit.abstractions, Version=2.0.0.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c">
       <HintPath>..\packages\xunit.abstractions.2.0.0\lib\net35\xunit.abstractions.dll</HintPath>
     </Reference>
-    <Reference Include="xunit.assert, Version=2.0.0.2929, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
+    <Reference Include="xunit.assert">
       <HintPath>..\packages\xunit.assert.2.0.0\lib\portable-net45+win+wpa81+wp80+monotouch+monoandroid+Xamarin.iOS\xunit.assert.dll</HintPath>
     </Reference>
-    <Reference Include="xunit.core, Version=2.0.0.2929, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
+    <Reference Include="xunit.core">
       <HintPath>..\packages\xunit.extensibility.core.2.0.0\lib\portable-net45+win+wpa81+wp80+monotouch+monoandroid+Xamarin.iOS\xunit.core.dll</HintPath>
     </Reference>
+ <Reference Include="System.Net.Http.Primitives">
+      <HintPath>..\packages\Microsoft.Net.Http.2.2.18\lib\net45\System.Net.Http.Primitives.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Net.Http.Extensions">
+      <HintPath>..\packages\Microsoft.Net.Http.2.2.18\lib\net45\System.Net.Http.Extensions.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Net.Http.WebRequest" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Authentication\CredentialsTests.cs" />
@@ -175,7 +181,7 @@
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Octokit\Octokit-Portable.csproj">
-      <Project>{ddb20481-e17d-4e0a-b2c0-ffff78d4ed71}</Project>
+      <Project>{DDB20481-E17D-4E0A-B2C0-FFFF78D4ED71}</Project>
       <Name>Octokit-Portable</Name>
     </ProjectReference>
   </ItemGroup>
diff --git a/Octokit.Tests/app.config b/Octokit.Tests/app.config
index 393911e6..ba29a2b9 100644
--- a/Octokit.Tests/app.config
+++ b/Octokit.Tests/app.config
@@ -13,7 +13,11 @@
       <dependentAssembly>
         <assemblyIdentity name="System.Reactive.Linq" publicKeyToken="31bf3856ad364e35" culture="neutral" />
         <bindingRedirect oldVersion="0.0.0.0-2.1.30214.0" newVersion="2.1.30214.0" />
-      </dependentAssembly>
+        </dependentAssembly>
+      <dependentAssembly>
+      <assemblyIdentity name="System.Net.Http.Primitives" publicKeyToken="b03f5f7f11d50a3a" culture="neutral"/>
+      <bindingRedirect oldVersion="0.0.0.0-4.0.10.0" newVersion="4.0.10.0"/>
+    </dependentAssembly>
     </assemblyBinding>
   </runtime>
-</configuration>
\ No newline at end of file
+</configuration>
diff --git a/Octokit.Tests/packages.Octokit.Tests-Portable.config b/Octokit.Tests/packages.Octokit.Tests-Portable.config
index 88ad4be6..e22e1bc8 100644
--- a/Octokit.Tests/packages.Octokit.Tests-Portable.config
+++ b/Octokit.Tests/packages.Octokit.Tests-Portable.config
@@ -3,6 +3,7 @@
   <package id="Microsoft.Bcl" version="1.1.6" targetFramework="net45" />
   <package id="Microsoft.Bcl.Build" version="1.0.13" targetFramework="net45" />
   <package id="Microsoft.Net.Http" version="2.2.18" targetFramework="net45" />
+  <package id="System.Net.Http" version="2.0.20710" targetFramework="net45" />
   <package id="NSubstitute" version="1.8.0.0" targetFramework="net45" />
   <package id="Rx-Core" version="2.2.5" targetFramework="net45" />
   <package id="Rx-Interfaces" version="2.2.5" targetFramework="net45" />
@@ -13,4 +14,4 @@
   <package id="xunit.core" version="2.0.0" targetFramework="net45" />
   <package id="xunit.extensibility.core" version="2.0.0" targetFramework="net45" />
   <package id="xunit.runner.visualstudio" version="2.0.0" targetFramework="net45" />
-</packages>
\ No newline at end of file
+</packages>