diff --git a/.gitignore b/.gitignore
index 15b0563c..831886c2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -49,7 +49,7 @@ UpgradeLog*.htm
 
 # OS
 $RECYCLE.BIN/
-.DS_Store/
+.DS_Store
 Thumbs.db
 ehthumbs.db
 Desktop.ini
diff --git a/MathNet.Numerics.XamariniOSOnly.sln b/MathNet.Numerics.XamariniOSOnly.sln
new file mode 100644
index 00000000..8fe99ad4
--- /dev/null
+++ b/MathNet.Numerics.XamariniOSOnly.sln
@@ -0,0 +1,23 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio 2012
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Numerics-XamariniOS", "src\Numerics\Numerics-XamariniOS.csproj", "{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}"
+EndProject
+Project("{f2a71f9b-5d33-465a-a702-920d77279786}") = "FSharp-XamariniOS", "src\FSharp\FSharp-XamariniOS.fsproj", "{F5F14E76-428D-43D7-8431-5B895F1BA419}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{F5F14E76-428D-43D7-8431-5B895F1BA419}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{F5F14E76-428D-43D7-8431-5B895F1BA419}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{F5F14E76-428D-43D7-8431-5B895F1BA419}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{F5F14E76-428D-43D7-8431-5B895F1BA419}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal
diff --git a/src/FSharp/BigIntegerExtensions.fs b/src/FSharp/BigIntegerExtensions.fs
index 9696a61e..e3aff48d 100644
--- a/src/FSharp/BigIntegerExtensions.fs
+++ b/src/FSharp/BigIntegerExtensions.fs
@@ -27,8 +27,7 @@ module BigIntegerExtensions =
                 raise <| FormatException ("The value could not be parsed.")
 
             if str.[0] = '-' then
-                parseImpl str len 0I 1
-                |> bigint.Negate
+                -(parseImpl str len 0I 1)
             else
                 parseImpl str len 0I 0
 
diff --git a/src/FSharp/FSharp-XamariniOS.fsproj b/src/FSharp/FSharp-XamariniOS.fsproj
new file mode 100644
index 00000000..652f566f
--- /dev/null
+++ b/src/FSharp/FSharp-XamariniOS.fsproj
@@ -0,0 +1,81 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <Name>FSharp-XamariniOS</Name>
+    <AssemblyName>MathNet.Numerics.FSharp</AssemblyName>
+    <RootNamespace>MathNet.Numerics</RootNamespace>
+    <OutputType>Library</OutputType>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{F5F14E76-428D-43D7-8431-5B895F1BA419}</ProjectGuid>
+    <ProjectTypeGuids>{FEACFBD2-3405-455C-9665-78FE426C6842};{F2A71F9B-5D33-465A-A702-920D77279786}</ProjectTypeGuids>
+    <IPhoneResourcePrefix>Resources</IPhoneResourcePrefix>
+    <BaseIntermediateOutputPath>..\..\obj\lib-debug\XamariniOS</BaseIntermediateOutputPath>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DefineConstants>TRACE;PORTABLE</DefineConstants>
+    <OutputPath>..\..\out\lib\XamariniOS\</OutputPath>
+    <IntermediateOutputPath>..\..\obj\lib\XamariniOS\</IntermediateOutputPath>
+    <BaseIntermediateOutputPath>..\..\obj\lib\XamariniOS\</BaseIntermediateOutputPath>
+    <DocumentationFile>..\..\out\lib\XamariniOS\MathNet.Numerics.FSharp.XML</DocumentationFile>
+    <Optimize>true</Optimize>
+    <Tailcalls>true</Tailcalls>
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <WarningLevel>3</WarningLevel>
+    <MtouchUseSGen>true</MtouchUseSGen>
+    <MtouchUseRefCounting>true</MtouchUseRefCounting>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DefineConstants>TRACE;DEBUG;PORTABLE</DefineConstants>
+    <OutputPath>..\..\out\lib-debug\XamariniOS\</OutputPath>
+    <IntermediateOutputPath>..\..\obj\lib-debug\XamariniOS\</IntermediateOutputPath>
+    <BaseIntermediateOutputPath>..\..\obj\lib-debug\XamariniOS\</BaseIntermediateOutputPath>
+    <Optimize>false</Optimize>
+    <Tailcalls>false</Tailcalls>
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <WarningLevel>3</WarningLevel>
+    <ConsolePause>false</ConsolePause>
+    <MtouchUseSGen>true</MtouchUseSGen>
+    <MtouchUseRefCounting>true</MtouchUseRefCounting>
+    <PlatformTarget></PlatformTarget>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="System" />
+    <Reference Include="System.Xml" />
+    <Reference Include="System.Core" />
+    <Reference Include="mscorlib" />
+    <Reference Include="FSharp.Core" />
+    <Reference Include="Xamarin.iOS" />
+  </ItemGroup>
+  <ItemGroup>
+    <Folder Include="Resources\" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="AssemblyInfo.fs" />
+    <Compile Include="Compatibility.fs" />
+    <Compile Include="Statistics.fs" />
+    <Compile Include="Random.fs" />
+    <Compile Include="Distributions.fs" />
+    <Compile Include="Generate.fs" />
+    <Compile Include="LinearAlgebra.Vector.fs" />
+    <Compile Include="LinearAlgebra.Matrix.fs" />
+    <Compile Include="Complex.fs" />
+    <Compile Include="BigIntegerExtensions.fs" />
+    <Compile Include="BigRational.fsi" />
+    <Compile Include="BigRational.fs" />
+    <Compile Include="Differentiate.fs" />
+    <Compile Include="Fit.fs" />
+    <Compile Include="FindRoots.fs" />
+    <Compile Include="RandomVariable.fs" />
+    <None Include="MathNet.Numerics.fsx" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\Numerics\Numerics-XamariniOS.csproj">
+      <Project>{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}</Project>
+      <Name>Numerics-XamariniOS</Name>
+    </ProjectReference>
+  </ItemGroup>
+  <Import Project="$(MSBuildExtensionsPath)\Xamarin\iOS\Xamarin.iOS.FSharp.targets" />
+</Project>
\ No newline at end of file
diff --git a/src/Numerics/Numerics-XamariniOS.csproj b/src/Numerics/Numerics-XamariniOS.csproj
new file mode 100644
index 00000000..b404c5c1
--- /dev/null
+++ b/src/Numerics/Numerics-XamariniOS.csproj
@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{1C8DCFB2-DB75-4C4B-888B-4AF315FCE3C3}</ProjectGuid>
+    <OutputType>Library</OutputType>
+    <RootNamespace>MathNet.Numerics</RootNamespace>
+    <AssemblyName>MathNet.Numerics</AssemblyName>
+    <ProjectTypeGuids>{FEACFBD2-3405-455C-9665-78FE426C6842};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
+    <IPhoneResourcePrefix>Resources</IPhoneResourcePrefix>
+    <BaseIntermediateOutputPath>..\..\obj\lib-debug\XamariniOS</BaseIntermediateOutputPath>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>..\..\out\lib-debug\XamariniOS\</OutputPath>
+    <IntermediateOutputPath>..\..\obj\lib-debug\XamariniOS\</IntermediateOutputPath>
+    <BaseIntermediateOutputPath>..\..\obj\lib-debug\XamariniOS\</BaseIntermediateOutputPath>
+    <DefineConstants>DEBUG;PORTABLE;NOSYSNUMERICS;NET45REFLECTION</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <ConsolePause>false</ConsolePause>
+    <MtouchUseSGen>true</MtouchUseSGen>
+    <MtouchUseRefCounting>true</MtouchUseRefCounting>
+    <MtouchLink></MtouchLink>
+    <MtouchHttpClientHandler></MtouchHttpClientHandler>
+    <MtouchTlsProvider></MtouchTlsProvider>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <Optimize>true</Optimize>
+    <OutputPath>..\..\out\lib\XamariniOS\</OutputPath>
+    <IntermediateOutputPath>..\..\obj\lib\XamariniOS\</IntermediateOutputPath>
+    <BaseIntermediateOutputPath>..\..\obj\lib\XamariniOS\</BaseIntermediateOutputPath>
+    <DefineConstants>PORTABLE;NOSYSNUMERICS;NET45REFLECTION</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <DocumentationFile>..\..\out\lib\XamariniOS\MathNet.Numerics.xml</DocumentationFile>
+    <ConsolePause>false</ConsolePause>
+    <MtouchUseSGen>true</MtouchUseSGen>
+    <MtouchUseRefCounting>true</MtouchUseRefCounting>
+    <MtouchLink></MtouchLink>
+    <MtouchHttpClientHandler></MtouchHttpClientHandler>
+    <MtouchTlsProvider></MtouchTlsProvider>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="System" />
+    <Reference Include="System.Xml" />
+    <Reference Include="System.Core" />
+    <Reference Include="Xamarin.iOS" />
+    <Reference Include="System.Runtime.Serialization" />
+  </ItemGroup>
+  <ItemGroup>
+    <Folder Include="Resources\" />
+  </ItemGroup>
+  <ItemGroup>
+    <EmbeddedResource Include="Properties\Resources.resx">
+      <Generator>PublicResXFileCodeGenerator</Generator>
+      <LastGenOutput>Resources.Designer.cs</LastGenOutput>
+      <SubType>Designer</SubType>
+    </EmbeddedResource>
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="**\*.cs" Exclude="Properties\Resources.Designer.cs">
+    </Compile>
+    <Compile Include="Properties\Resources.Designer.cs">
+      <AutoGen>True</AutoGen>
+      <DesignTime>True</DesignTime>
+      <DependentUpon>Resources.resx</DependentUpon>
+    </Compile>
+  </ItemGroup>
+  <Import Project="$(MSBuildExtensionsPath)\Xamarin\iOS\Xamarin.iOS.CSharp.targets" />
+</Project>
\ No newline at end of file