diff --git a/csharp/App.config b/csharp/App.config
index 88fa4027..5ab1a356 100644
--- a/csharp/App.config
+++ b/csharp/App.config
@@ -1,6 +1,6 @@
-<?xml version="1.0" encoding="utf-8" ?>
+<?xml version="1.0" encoding="utf-8"?>
 <configuration>
     <startup> 
-        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.2" />
+        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.8.1"/>
     </startup>
-</configuration>
\ No newline at end of file
+</configuration>
diff --git a/csharp/csharp.csproj b/csharp/csharp.csproj
index 58213647..db182545 100644
--- a/csharp/csharp.csproj
+++ b/csharp/csharp.csproj
@@ -1,6 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <Import Project="packages\NUnit3TestAdapter.3.9.0\build\net35\NUnit3TestAdapter.props" Condition="Exists('packages\NUnit3TestAdapter.3.9.0\build\net35\NUnit3TestAdapter.props')" />
+  <Import Project="packages\ApprovalTests.5.9.0\build\ApprovalTests.props" Condition="Exists('packages\ApprovalTests.5.9.0\build\ApprovalTests.props')" />
+  <Import Project="packages\NUnit3TestAdapter.4.5.0\build\net462\NUnit3TestAdapter.props" Condition="Exists('packages\NUnit3TestAdapter.4.5.0\build\net462\NUnit3TestAdapter.props')" />
+  <Import Project="packages\NUnit.3.13.3\build\NUnit.props" Condition="Exists('packages\NUnit.3.13.3\build\NUnit.props')" />
   <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
@@ -10,11 +12,12 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>csharp</RootNamespace>
     <AssemblyName>csharp</AssemblyName>
-    <TargetFrameworkVersion>v4.5.2</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.8.1</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>
     <NuGetPackageImportStamp>
     </NuGetPackageImportStamp>
+    <TargetFrameworkProfile />
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <PlatformTarget>AnyCPU</PlatformTarget>
@@ -37,28 +40,77 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="ApprovalTests, Version=3.0.0.0, Culture=neutral, PublicKeyToken=11bd7d124fc62e0f, processorArchitecture=MSIL">
-      <HintPath>packages\ApprovalTests.3.0.13\lib\net40\ApprovalTests.dll</HintPath>
-      <Private>True</Private>
+      <HintPath>packages\ApprovalTests.5.9.0\lib\net462\ApprovalTests.dll</HintPath>
     </Reference>
     <Reference Include="ApprovalUtilities, Version=3.0.0.0, Culture=neutral, PublicKeyToken=11bd7d124fc62e0f, processorArchitecture=MSIL">
-      <HintPath>packages\ApprovalUtilities.3.0.13\lib\net45\ApprovalUtilities.dll</HintPath>
-      <Private>True</Private>
+      <HintPath>packages\ApprovalUtilities.5.9.0\lib\net462\ApprovalUtilities.dll</HintPath>
     </Reference>
-    <Reference Include="ApprovalUtilities.Net45, Version=3.0.0.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>packages\ApprovalUtilities.3.0.13\lib\net45\ApprovalUtilities.Net45.dll</HintPath>
-      <Private>True</Private>
+    <Reference Include="DiffEngine, Version=1.0.0.0, Culture=neutral, PublicKeyToken=c7a34512ecd69090, processorArchitecture=MSIL">
+      <HintPath>packages\DiffEngine.12.2.1\lib\net48\DiffEngine.dll</HintPath>
     </Reference>
-    <Reference Include="nunit.framework, Version=3.9.0.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
-      <HintPath>packages\NUnit.3.9.0\lib\net45\nunit.framework.dll</HintPath>
+    <Reference Include="EmptyFiles, Version=1.0.0.0, Culture=neutral, PublicKeyToken=c7a34512ecd69090, processorArchitecture=MSIL">
+      <HintPath>packages\EmptyFiles.4.5.0\lib\net461\EmptyFiles.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.Bcl.AsyncInterfaces, Version=7.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\Microsoft.Bcl.AsyncInterfaces.7.0.0\lib\net462\Microsoft.Bcl.AsyncInterfaces.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.Extensions.DependencyInjection.Abstractions, Version=7.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60, processorArchitecture=MSIL">
+      <HintPath>packages\Microsoft.Extensions.DependencyInjection.Abstractions.7.0.0\lib\net462\Microsoft.Extensions.DependencyInjection.Abstractions.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.Win32.Registry, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\Microsoft.Win32.Registry.5.0.0\lib\net461\Microsoft.Win32.Registry.dll</HintPath>
+    </Reference>
+    <Reference Include="nunit.framework, Version=3.13.3.0, Culture=neutral, PublicKeyToken=2638cd05610744eb, processorArchitecture=MSIL">
+      <HintPath>packages\NUnit.3.13.3\lib\net45\nunit.framework.dll</HintPath>
     </Reference>
     <Reference Include="System" />
+    <Reference Include="System.Buffers, Version=4.0.3.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\System.Buffers.4.5.1\lib\net461\System.Buffers.dll</HintPath>
+    </Reference>
+    <Reference Include="System.CodeDom, Version=6.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\System.CodeDom.6.0.0\lib\net461\System.CodeDom.dll</HintPath>
+    </Reference>
     <Reference Include="System.Core" />
+    <Reference Include="System.Data.SqlClient, Version=4.6.1.5, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Data.SqlClient.4.8.5\lib\net461\System.Data.SqlClient.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Management" />
+    <Reference Include="System.Memory, Version=4.0.1.2, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\System.Memory.4.5.5\lib\net461\System.Memory.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Numerics" />
+    <Reference Include="System.Numerics.Vectors, Version=4.1.4.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Numerics.Vectors.4.5.0\lib\net46\System.Numerics.Vectors.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Runtime.CompilerServices.Unsafe.4.5.3\lib\net461\System.Runtime.CompilerServices.Unsafe.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Runtime.InteropServices.RuntimeInformation, Version=4.0.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Runtime.InteropServices.RuntimeInformation.4.3.0\lib\net45\System.Runtime.InteropServices.RuntimeInformation.dll</HintPath>
+      <Private>True</Private>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="System.Security.AccessControl, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Security.AccessControl.6.0.0\lib\net461\System.Security.AccessControl.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Security.Principal.Windows, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Security.Principal.Windows.5.0.0\lib\net461\System.Security.Principal.Windows.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Threading.Tasks.Extensions, Version=4.2.0.1, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\System.Threading.Tasks.Extensions.4.5.4\lib\net461\System.Threading.Tasks.Extensions.dll</HintPath>
+    </Reference>
+    <Reference Include="System.ValueTuple, Version=4.0.3.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\System.ValueTuple.4.5.0\lib\net47\System.ValueTuple.dll</HintPath>
+    </Reference>
     <Reference Include="System.Xml.Linq" />
     <Reference Include="System.Data.DataSetExtensions" />
     <Reference Include="Microsoft.CSharp" />
     <Reference Include="System.Data" />
     <Reference Include="System.Net.Http" />
     <Reference Include="System.Xml" />
+    <Reference Include="TextCopy, Version=1.0.0.0, Culture=neutral, PublicKeyToken=1ca091877d12ca03, processorArchitecture=MSIL">
+      <HintPath>packages\TextCopy.6.2.1\lib\net462\TextCopy.dll</HintPath>
+    </Reference>
   </ItemGroup>
   <ItemGroup>
     <Compile Include="ApprovalTest.cs" />
@@ -80,8 +132,14 @@
     <PropertyGroup>
       <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
     </PropertyGroup>
-    <Error Condition="!Exists('packages\NUnit3TestAdapter.3.9.0\build\net35\NUnit3TestAdapter.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\NUnit3TestAdapter.3.9.0\build\net35\NUnit3TestAdapter.props'))" />
+    <Error Condition="!Exists('packages\NUnit.3.13.3\build\NUnit.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\NUnit.3.13.3\build\NUnit.props'))" />
+    <Error Condition="!Exists('packages\NUnit3TestAdapter.4.5.0\build\net462\NUnit3TestAdapter.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\NUnit3TestAdapter.4.5.0\build\net462\NUnit3TestAdapter.props'))" />
+    <Error Condition="!Exists('packages\EmptyFiles.4.5.0\build\EmptyFiles.targets')" Text="$([System.String]::Format('$(ErrorText)', 'packages\EmptyFiles.4.5.0\build\EmptyFiles.targets'))" />
+    <Error Condition="!Exists('packages\ApprovalTests.5.9.0\build\ApprovalTests.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\ApprovalTests.5.9.0\build\ApprovalTests.props'))" />
+    <Error Condition="!Exists('packages\ApprovalTests.5.9.0\build\ApprovalTests.targets')" Text="$([System.String]::Format('$(ErrorText)', 'packages\ApprovalTests.5.9.0\build\ApprovalTests.targets'))" />
   </Target>
+  <Import Project="packages\EmptyFiles.4.5.0\build\EmptyFiles.targets" Condition="Exists('packages\EmptyFiles.4.5.0\build\EmptyFiles.targets')" />
+  <Import Project="packages\ApprovalTests.5.9.0\build\ApprovalTests.targets" Condition="Exists('packages\ApprovalTests.5.9.0\build\ApprovalTests.targets')" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">
diff --git a/csharp/packages.config b/csharp/packages.config
index 63895ed1..52a78b1b 100644
--- a/csharp/packages.config
+++ b/csharp/packages.config
@@ -1,7 +1,25 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="ApprovalTests" version="3.0.13" targetFramework="net452" />
-  <package id="ApprovalUtilities" version="3.0.13" targetFramework="net452" />
-  <package id="NUnit" version="3.9.0" targetFramework="net452" />
-  <package id="NUnit3TestAdapter" version="3.9.0" targetFramework="net452" />
+  <package id="ApprovalTests" version="5.9.0" targetFramework="net481" />
+  <package id="ApprovalUtilities" version="5.9.0" targetFramework="net481" />
+  <package id="DiffEngine" version="12.2.1" targetFramework="net481" />
+  <package id="EmptyFiles" version="4.5.0" targetFramework="net481" />
+  <package id="Microsoft.Bcl.AsyncInterfaces" version="7.0.0" targetFramework="net481" />
+  <package id="Microsoft.Extensions.DependencyInjection.Abstractions" version="7.0.0" targetFramework="net481" />
+  <package id="Microsoft.Win32.Registry" version="5.0.0" targetFramework="net481" />
+  <package id="NUnit" version="3.13.3" targetFramework="net481" />
+  <package id="NUnit3TestAdapter" version="4.5.0" targetFramework="net481" />
+  <package id="System.Buffers" version="4.5.1" targetFramework="net481" />
+  <package id="System.CodeDom" version="6.0.0" targetFramework="net481" />
+  <package id="System.Data.SqlClient" version="4.8.5" targetFramework="net481" />
+  <package id="System.Management" version="6.0.2" targetFramework="net481" />
+  <package id="System.Memory" version="4.5.5" targetFramework="net481" />
+  <package id="System.Numerics.Vectors" version="4.5.0" targetFramework="net481" />
+  <package id="System.Runtime.CompilerServices.Unsafe" version="4.5.3" targetFramework="net481" />
+  <package id="System.Runtime.InteropServices.RuntimeInformation" version="4.3.0" targetFramework="net481" />
+  <package id="System.Security.AccessControl" version="6.0.0" targetFramework="net481" />
+  <package id="System.Security.Principal.Windows" version="5.0.0" targetFramework="net481" />
+  <package id="System.Threading.Tasks.Extensions" version="4.5.4" targetFramework="net481" />
+  <package id="System.ValueTuple" version="4.5.0" targetFramework="net481" />
+  <package id="TextCopy" version="6.2.1" targetFramework="net481" />
 </packages>
\ No newline at end of file