Convert ext\ to MSTest and traversal projects.

- Move ext\ unit tests to MSTest.
- MSBuildify ext projects with MSTest execution.
- Fork test support projects for MSTest:
  - WixInternal.TestSupport
  - WixInternal.Core.TestPackage

96 files changed, 3204 insertions, 767 deletions

diff --git a/src/Directory.Build.props b/src/Directory.Build.props
index 2de04127..883aba42 100644
--- a/src/Directory.Build.props
+++ b/src/Directory.Build.props
@@ -11,7 +11,9 @@
     <ProjectName Condition=" '$(ProjectName)' == '' ">$(MSBuildProjectName)</ProjectName>
     <RootBuildFolder>$([System.IO.Path]::GetFullPath($(MSBuildThisFileDirectory)..\build\))</RootBuildFolder>
     <RootPackagesFolder>$([System.IO.Path]::GetFullPath($(MSBuildThisFileDirectory)..\packages\))</RootPackagesFolder>
-    <PdbsFolder>$(RootBuildFolder)logs\pdbs\$(Configuration)\</PdbsFolder>
+    <LogsFolder>$(RootBuildFolder)logs\</LogsFolder>
+    <TestResultsFolder>$(LogsFolder)TestResults\</TestResultsFolder>
+    <PdbsFolder>$(LogsFolder)pdbs\$(Configuration)\</PdbsFolder>
     <ArtifactsFolder>$(RootBuildFolder)artifacts\</ArtifactsFolder>
     <ToolsFolder>$(RootBuildFolder).tools</ToolsFolder>
     <PackageOutputPath>$(ArtifactsFolder)</PackageOutputPath>
diff --git a/src/Directory.csproj.targets b/src/Directory.csproj.targets
index 2c6abce3..ed041bb8 100644
--- a/src/Directory.csproj.targets
+++ b/src/Directory.csproj.targets
@@ -7,18 +7,36 @@
     <DefineConstants Condition=" '$(Configuration)'=='Debug' ">$(DefineConstants);DEBUG</DefineConstants>
   </PropertyGroup>
 
-  <PropertyGroup Condition=" '$(IsWixTestProject)'=='true' ">
+  <PropertyGroup Condition=" '$(IsWixTestProject)'=='true' OR '$(IsWixMSTestProject)'=='true' ">
     <RollForward>Major</RollForward>
     <IsPackable>false</IsPackable>
     <SignOutput>false</SignOutput>
   </PropertyGroup>
 
+
+  <PropertyGroup Condition=" '$(IsWixMSTestProject)' == 'true' ">
+    <!-- Force a .NET v6-compatible package. -->
+    <MicrosoftTestingExtensionsCodeCoverageVersion>17.11.5</MicrosoftTestingExtensionsCodeCoverageVersion>
+    <TestingPlatformShowTestsFailure>true</TestingPlatformShowTestsFailure>
+  </PropertyGroup>
+
+  <Target Name="RunWixTests" AfterTargets="Build" Condition=" '$(IsWixMSTestProject)' == 'true' AND '$(SuppressWixTests)' != 'true' ">
+    <Delete Files="$(TestResultsFolder)$(MSBuildProjectName).trx" />
+
+    <Exec 
+      Command="$(TargetPath.Replace('.dll', '.exe')) --results-directory $(TestResultsFolder) --report-trx --report-trx-filename $(MSBuildProjectName).trx --no-progress --settings $([MSBuild]::GetPathOfFileAbove('wix.runsettings'))" 
+      UseCommandProcessor="false" 
+      CustomErrorRegularExpression="  Test method .+ threw exception:" />
+  </Target>   
+
+
   <ItemGroup Condition=" '$(IsWixTestProject)'=='true' ">
     <PackageReference Include="Microsoft.NET.Test.Sdk" />
     <PackageReference Include="xunit" />
     <PackageReference Include="xunit.runner.visualstudio" PrivateAssets="All" />
   </ItemGroup>
 
+
   <ItemGroup Condition=" '$(IsWixTestProject)'!='true' ">
     <PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="All" />
   </ItemGroup>
diff --git a/src/clean.cmd b/src/clean.cmd
index 6164a8f9..dc69f855 100644
--- a/src/clean.cmd
+++ b/src/clean.cmd
@@ -19,7 +19,9 @@ if exist ..\global.json (del ..\global.json)
 
 if exist "%_NUGET_CACHE%\wixinternal.basebuildtasks.sources" rd /s/q "%_NUGET_CACHE%\wixinternal.basebuildtasks.sources"
 if exist "%_NUGET_CACHE%\wixinternal.testsupport" rd /s/q "%_NUGET_CACHE%\wixinternal.testsupport"
+if exist "%_NUGET_CACHE%\wixinternal.mstestsupport" rd /s/q "%_NUGET_CACHE%\wixinternal.mstestsupport"
 if exist "%_NUGET_CACHE%\wixinternal.core.testpackage" rd /s/q "%_NUGET_CACHE%\wixinternal.core.testpackage"
+if exist "%_NUGET_CACHE%\wixinternal.core.mstestpackage" rd /s/q "%_NUGET_CACHE%\wixinternal.core.mstestpackage"
 if exist "%_NUGET_CACHE%\wixtoolset.bal.wixext" rd /s/q "%_NUGET_CACHE%\wixtoolset.bal.wixext"
 if exist "%_NUGET_CACHE%\wixtoolset.bootstrapperapplications.wixext" rd /s/q "%_NUGET_CACHE%\wixtoolset.bootstrapperapplications.wixext"
 if exist "%_NUGET_CACHE%\wixtoolset.bootstrapperextensionapi" rd /s/q "%_NUGET_CACHE%\wixtoolset.bootstrapperextensionapi"
diff --git a/src/ext/Bal/bal.cmd b/src/ext/Bal/bal.cmd
deleted file mode 100644
index df9ceca4..00000000
--- a/src/ext/Bal/bal.cmd
+++ /dev/null
@@ -1,55 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-@set _L=%~dp0..\..\..\build\logs
-
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if /i "%1"=="inc" set _INC=1
-@if /i "%1"=="clean" set _CLEAN=1
-@if not "%1"=="" shift & goto parse_args
-
-@set _B=%~dp0..\..\..\build\Bal.wixext\%_C%
-
-:: Clean
-
-@if "%_INC%"=="" call :clean
-@if NOT "%_CLEAN%"=="" goto :end
-
-@echo Building ext\Bal %_C% using %_N%
-
-:: Restore
-:: Build
-:: Pack
-:: Note: This test project must be restored and built directly to get all its support files laid out correctly.
-::       Everything else is built by the traversal project.
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -m -warnaserror test\WixToolsetTest.BootstrapperApplications\WixToolsetTest.BootstrapperApplications.csproj -bl:%_L%\ext_bal_build.binlog || exit /b
-
-msbuild bal_t.proj -p:Configuration=%_C% -tl -nologo -warnaserror -bl:%_L%\bal_build.binlog || exit /b
-
-:: Test
-dotnet test ^
-  %_B%\x86\WixStdFnUnitTest.dll ^
-  %_B%\net6.0\WixToolsetTest.BootstrapperApplications.dll ^
-  --nologo -l "trx;LogFileName=%_L%\TestResults\bal.wixext.trx" || exit /b
-
-@goto :end
-
-:clean
-@rd /s/q "..\..\..\build\Bal.wixext" 2> nul
-@del "..\..\..\build\artifacts\WixToolset.Bal.wixext.*.nupkg" 2> nul
-@del "..\..\..\build\artifacts\WixToolset.BootstrapperApplications.wixext.*.nupkg" 2> nul
-@del "..\..\..\build\artifacts\WixToolset.WixStandardBootstrapperApplicationFunctionApi.*.nupkg" 2> nul
-@del "%_L%\ext_bal_build.binlog" 2> nul
-@del "%_L%\bal_fnsapi_build.binlog" 2> nul
-@del "%_L%\bal_examples_build.binlog" 2> nul
-@del "%_L%\TestResults\bal.wixext.trx" 2> nul
-@rd /s/q "%USERPROFILE%\.nuget\packages\wixtoolset.bal.wixext" 2> nul
-@rd /s/q "%USERPROFILE%\.nuget\packages\wixtoolset.bootstrapperapplications.wixext" 2> nul
-@rd /s/q "%USERPROFILE%\.nuget\packages\wixtoolset.wixstandardbootstrapperapplicationfunctionapi" 2> nul
-@exit /b
-
-:end
-@popd
-@endlocal
diff --git a/src/ext/Bal/bal_t.proj b/src/ext/Bal/bal_t.proj
index a0e66e97..da83b47f 100644
--- a/src/ext/Bal/bal_t.proj
+++ b/src/ext/Bal/bal_t.proj
@@ -3,13 +3,6 @@
 
 <Project Sdk="Microsoft.Build.Traversal">
   <ItemGroup>
-    <!-- Restore: Explicitly restore the test projects, which need some hand-holding. -->
-    <ProjectReference Include="test\WixStdFnUnitTest\WixStdFnUnitTest.vcxproj" Targets="Restore" BuildInParallel="false" />
-    <ProjectReference Include="test\examples\examples.proj" Targets="Restore" />
-    <ProjectReference Include="wixext-backward-compatible\WixToolset.Bal.wixext.csproj" Targets="Restore" />
-
-    <!-- Build -->
-
     <!-- C++/CLI projects will try to build their dependent projects in parallel with others, so they must be built first. -->
     <ProjectReference Include="test\WixStdFnUnitTest\WixStdFnUnitTest.vcxproj" Properties="Platform=x86" BuildInParallel="false" />
 
@@ -17,11 +10,33 @@
     <ProjectReference Include="wixstdfn\wixstdfn.vcxproj" Properties="Platform=x64" />
     <ProjectReference Include="wixstdfn\wixstdfn.vcxproj" Properties="Platform=ARM64" />
 
-    <ProjectReference Include="test\examples\examples.proj" />
+    <ProjectReference Include="test\WixToolsetTest.BootstrapperApplications\WixToolsetTest.BootstrapperApplications.csproj" Properties="Platform=x64" />
 
-    <!-- Pack -->
     <ProjectReference Include="wixstdfn\wixstdfn.vcxproj" Properties="NoBuild=true" Targets="PackNative" />
     <ProjectReference Include="wixext\WixToolset.BootstrapperApplications.wixext.csproj" Properties="NoBuild=true" Targets="Pack" />
     <ProjectReference Include="wixext-backward-compatible\WixToolset.Bal.wixext.csproj" Targets="Pack" />
+
+    <ProjectReference Include="test\examples\examples.proj" />
+
+    <!-- 
+    Currently there are no unskipped unit tests in this project. Should that change,
+    we'll need to update the native test framework or figure out something else.
+
+    <ProjectReference Include="ext\Bal\test\WixStdFnUnitTest\WixStdFnUnitTest.vcxproj" /> 
+    -->
   </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)Bal.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.bal.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.bal.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.bootstrapperapplications.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.bootstrapperapplications.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.wixstandardbootstrapperapplicationfunctionapi.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.wixstandardbootstrapperapplicationfunctionapi.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Bal.wixext.*.nupkg" />
+    <Delete Files="$(ArtifactsFolder)WixToolset.BootstrapperApplications.wixext.*.nupkg" />
+    <Delete Files="$(ArtifactsFolder)WixToolset.WixStandardBootstrapperApplicationFunctionApi.wixext.*.nupkg" />
+  </Target>
 </Project>
diff --git a/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/BalExtensionFixture.cs b/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/BalExtensionFixture.cs
index 2e21ef90..6e24ad72 100644
--- a/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/BalExtensionFixture.cs
+++ b/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/BalExtensionFixture.cs
@@ -6,13 +6,14 @@ namespace WixToolsetTest.BootstrapperApplications
     using System.Collections.Generic;
     using System.IO;
     using System.Linq;
-    using WixInternal.Core.TestPackage;
-    using WixInternal.TestSupport;
-    using Xunit;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.Core.MSTestPackage;
+    using WixInternal.MSTestSupport;
 
+    [TestClass]
     public class BalExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingDisplayInternalUICondition()
         {
             using (var fs = new DisposableFileSystem())
@@ -35,7 +36,7 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -46,11 +47,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "<WixBalPackageInfo PackageId='test.msi' DisplayInternalUICondition='1' />",
                 }, balPackageInfos);
 
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "thm.wxl")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "thm.wxl")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingBootstrapperApplicationId()
         {
             using (var fs = new DisposableFileSystem())
@@ -73,7 +74,7 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -91,7 +92,7 @@ namespace WixToolsetTest.BootstrapperApplications
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingOverridable()
         {
             using (var fs = new DisposableFileSystem())
@@ -113,7 +114,7 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -132,7 +133,7 @@ namespace WixToolsetTest.BootstrapperApplications
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixStdBa()
         {
             using (var fs = new DisposableFileSystem())
@@ -152,11 +153,11 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
             }
         }
 
-        //[Fact]
+        // [TestMethod]
         //public void CanBuildUsingMBAWithAlwaysInstallPrereqs()
         //{
         //    using (var fs = new DisposableFileSystem())
@@ -179,7 +180,7 @@ namespace WixToolsetTest.BootstrapperApplications
 
         //        compileResult.AssertSuccess();
 
-        //        Assert.True(File.Exists(bundleFile));
+        //        Assert.IsTrue(File.Exists(bundleFile));
 
         //        var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
         //        extractResult.AssertSuccess();
@@ -198,7 +199,7 @@ namespace WixToolsetTest.BootstrapperApplications
         //    }
         //}
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingMBAWithNoPrereqs()
         {
             using (var fs = new DisposableFileSystem())
@@ -223,14 +224,14 @@ namespace WixToolsetTest.BootstrapperApplications
                 {
                     "The WixManagedBootstrapperApplicationHost element has been deprecated.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
-                Assert.Equal(1130, compileResult.ExitCode);
+                Assert.AreEqual(1130, compileResult.ExitCode);
 
-                Assert.False(File.Exists(bundleFile));
-                Assert.False(File.Exists(Path.Combine(intermediateFolder, "test.exe")));
+                Assert.IsFalse(File.Exists(bundleFile));
+                Assert.IsFalse(File.Exists(Path.Combine(intermediateFolder, "test.exe")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingDncbaMissingBAFactoryPayload()
         {
             using (var fs = new DisposableFileSystem())
@@ -254,14 +255,14 @@ namespace WixToolsetTest.BootstrapperApplications
                     "The WixDotNetCoreBootstrapperApplicationHost element has been deprecated.",
                     "The BootstrapperApplication element's Name or SourceFile attribute was not found; one of these is required."
                 }, compileResult.Messages.Select(x => x.ToString()).ToArray());
-                Assert.Equal(44, compileResult.ExitCode);
+                Assert.AreEqual(44, compileResult.ExitCode);
 
-                Assert.False(File.Exists(bundleFile));
-                Assert.False(File.Exists(Path.Combine(intermediateFolder, "test.exe")));
+                Assert.IsFalse(File.Exists(bundleFile));
+                Assert.IsFalse(File.Exists(Path.Combine(intermediateFolder, "test.exe")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingOverridableWrongCase()
         {
             using (var fs = new DisposableFileSystem())
@@ -284,7 +285,7 @@ namespace WixToolsetTest.BootstrapperApplications
                     "-o", bundleFile,
                 });
 
-                Assert.InRange(result.ExitCode, 2, Int32.MaxValue);
+                Assert.IsTrue(result.ExitCode >= 2 && result.ExitCode <= Int32.MaxValue);
 
                 var messages = result.Messages.Select(m => m.ToString()).ToList();
                 messages.Sort();
diff --git a/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/InternalUIBAFixture.cs b/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/InternalUIBAFixture.cs
index 58d5d551..72e31540 100644
--- a/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/InternalUIBAFixture.cs
+++ b/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/InternalUIBAFixture.cs
@@ -5,13 +5,14 @@ namespace WixToolsetTest.BootstrapperApplications
     using System.IO;
     using System.Linq;
     using System.Xml;
-    using WixInternal.Core.TestPackage;
-    using WixInternal.TestSupport;
-    using Xunit;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.Core.MSTestPackage;
+    using WixInternal.MSTestSupport;
 
+    [TestClass]
     public class InternalUIBAFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixIuiBa()
         {
             using (var fs = new DisposableFileSystem())
@@ -34,7 +35,7 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -45,12 +46,12 @@ namespace WixToolsetTest.BootstrapperApplications
                     "<WixBalPackageInfo PackageId='test.msi' PrimaryPackageType='default' />",
                 }, balPackageInfos);
 
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixIuiBaWithUrlPrereqPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -73,7 +74,7 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -90,12 +91,12 @@ namespace WixToolsetTest.BootstrapperApplications
                     "<WixPrereqInformation PackageId='wixnative.exe' LicenseUrl='https://www.mysite.com/prereqterms' />",
                 }, mbaPrereqInfos);
 
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixIuiBaWithImplicitPrimaryPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -118,7 +119,7 @@ namespace WixToolsetTest.BootstrapperApplications
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -135,12 +136,12 @@ namespace WixToolsetTest.BootstrapperApplications
                     "<WixPrereqInformation PackageId='wixnative.exe' />",
                 }, mbaPrereqInfos);
 
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixIuiBaWithWarnings()
         {
             using (var fs = new DisposableFileSystem())
@@ -172,7 +173,7 @@ namespace WixToolsetTest.BootstrapperApplications
 
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -189,12 +190,12 @@ namespace WixToolsetTest.BootstrapperApplications
                     "<WixPrereqInformation PackageId='wixnative.exe' />",
                 }, mbaPrereqInfos);
 
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixIuiBaAndForcedCachePrimaryPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -218,7 +219,7 @@ namespace WixToolsetTest.BootstrapperApplications
 
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundleFile, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
@@ -239,8 +240,8 @@ namespace WixToolsetTest.BootstrapperApplications
                     "<WixPrereqInformation PackageId='wixnative.exe' />",
                 }, mbaPrereqInfos);
 
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
-                Assert.True(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.thm")));
+                Assert.IsTrue(File.Exists(Path.Combine(baFolderPath, "wixpreq.wxl")));
             }
 
             static void AssertCacheType(XmlNode node)
@@ -251,16 +252,16 @@ namespace WixToolsetTest.BootstrapperApplications
 
                 if (package == "test.msi")
                 {
-                    Assert.Equal("force", cache);
+                    Assert.AreEqual("force", cache);
                 }
                 else if (package == "wixnative.exe")
                 {
-                    Assert.Equal("keep", cache);
+                    Assert.AreEqual("keep", cache);
                 }
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithAllPrereqPackages()
         {
             using (var fs = new DisposableFileSystem())
@@ -285,11 +286,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, there must be one package with bal:PrimaryPackageType=\"default\".",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6808, compileResult.ExitCode);
+                Assert.AreEqual(6808, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithImplicitNonMsiPrimaryPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -314,11 +315,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, packages must either be non-permanent and have the bal:PrimaryPackageType attribute, or be permanent and have the bal:PrereqPackage attribute set to 'yes'.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6811, compileResult.ExitCode);
+                Assert.AreEqual(6811, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithImplicitPrimaryPackageEnableFeatureSelection()
         {
             using (var fs = new DisposableFileSystem())
@@ -343,11 +344,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, packages must either be non-permanent and have the bal:PrimaryPackageType attribute, or be permanent and have the bal:PrereqPackage attribute set to 'yes'.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6811, compileResult.ExitCode);
+                Assert.AreEqual(6811, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithMultipleNonPermanentNonPrimaryPackages()
         {
             using (var fs = new DisposableFileSystem())
@@ -373,11 +374,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, packages must either be non-permanent and have the bal:PrimaryPackageType attribute, or be permanent and have the bal:PrereqPackage attribute set to 'yes'.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6811, compileResult.ExitCode);
+                Assert.AreEqual(6811, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithMultiplePrimaryPackagesOfSameType()
         {
             using (var fs = new DisposableFileSystem())
@@ -403,11 +404,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "The location of the package related to the previous error.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6810, compileResult.ExitCode);
+                Assert.AreEqual(6810, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithNoDefaultPrimaryPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -432,11 +433,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, there must be one package with bal:PrimaryPackageType=\"default\".",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6808, compileResult.ExitCode);
+                Assert.AreEqual(6808, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithNonMsiPrimaryPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -461,11 +462,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, each primary package must be an MsiPackage.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6814, compileResult.ExitCode);
+                Assert.AreEqual(6814, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithNonPermanentPrereqPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -490,11 +491,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication and bal:PrereqPackage is set to 'yes', the package must be permanent.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6812, compileResult.ExitCode);
+                Assert.AreEqual(6812, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithPermanentPrimaryPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -520,11 +521,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, there must be one package with bal:PrimaryPackageType=\"default\".",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6808, compileResult.ExitCode);
+                Assert.AreEqual(6808, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithPrimaryPackageEnableFeatureSelection()
         {
             using (var fs = new DisposableFileSystem())
@@ -550,11 +551,11 @@ namespace WixToolsetTest.BootstrapperApplications
                     "When using WixInternalUIBootstrapperApplication, there must be one package with bal:PrimaryPackageType=\"default\".",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(6808, compileResult.ExitCode);
+                Assert.AreEqual(6808, compileResult.ExitCode);
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildUsingWixIuiBaWithPrimaryPrereqPackage()
         {
             using (var fs = new DisposableFileSystem())
@@ -578,7 +579,7 @@ namespace WixToolsetTest.BootstrapperApplications
                     "The MsiPackage/@PrereqPackage attribute's value, 'yes', cannot be specified with attribute PrimaryPackageType present.",
                 }, compileResult.Messages.Select(m => m.ToString()).ToArray());
 
-                Assert.Equal(193, compileResult.ExitCode);
+                Assert.AreEqual(193, compileResult.ExitCode);
             }
         }
     }
diff --git a/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/WixToolsetTest.BootstrapperApplications.csproj b/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/WixToolsetTest.BootstrapperApplications.csproj
index 64fc297c..6a9b5856 100644
--- a/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/WixToolsetTest.BootstrapperApplications.csproj
+++ b/src/ext/Bal/test/WixToolsetTest.BootstrapperApplications/WixToolsetTest.BootstrapperApplications.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -20,6 +20,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/ComPlus/complus.cmd b/src/ext/ComPlus/complus.cmd
deleted file mode 100644
index 3b3a5772..00000000
--- a/src/ext/ComPlus/complus.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo ComPlus.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.ComPlus || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.ComPlus.wixext.csproj || exit /b
-
-@popd
-@endlocal
\ No newline at end of file
diff --git a/src/ext/ComPlus/complus_t.proj b/src/ext/ComPlus/complus_t.proj
new file mode 100644
index 00000000..439856b6
--- /dev/null
+++ b/src/ext/ComPlus/complus_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.ComPlus\WixToolsetTest.ComPlus.csproj" />
+    <ProjectReference Include="wixext\WixToolset.ComPlus.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)complus.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.complus.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.complus.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.ComPlus.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/ComPlus/test/WixToolsetTest.ComPlus/ComPlusExtensionFixture.cs b/src/ext/ComPlus/test/WixToolsetTest.ComPlus/ComPlusExtensionFixture.cs
index 17c5eb0f..7b38ef54 100644
--- a/src/ext/ComPlus/test/WixToolsetTest.ComPlus/ComPlusExtensionFixture.cs
+++ b/src/ext/ComPlus/test/WixToolsetTest.ComPlus/ComPlusExtensionFixture.cs
@@ -3,14 +3,15 @@
 namespace WixToolsetTest.ComPlus
 {
     using System.Linq;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.ComPlus;
-    using Xunit;
 
+    [TestClass]
     public class ComPlusExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingComPlusPartition()
         {
             var folder = TestData.Get(@"TestData\UsingComPlusPartition");
diff --git a/src/ext/ComPlus/test/WixToolsetTest.ComPlus/WixToolsetTest.ComPlus.csproj b/src/ext/ComPlus/test/WixToolsetTest.ComPlus/WixToolsetTest.ComPlus.csproj
index a9e9dbef..d0a7081b 100644
--- a/src/ext/ComPlus/test/WixToolsetTest.ComPlus/WixToolsetTest.ComPlus.csproj
+++ b/src/ext/ComPlus/test/WixToolsetTest.ComPlus/WixToolsetTest.ComPlus.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Dependency/dependency.cmd b/src/ext/Dependency/dependency.cmd
deleted file mode 100644
index 0ebcbfd5..00000000
--- a/src/ext/Dependency/dependency.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo Dependency.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.Dependency || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.Dependency.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/Dependency/dependency_t.proj b/src/ext/Dependency/dependency_t.proj
new file mode 100644
index 00000000..d05b8de9
--- /dev/null
+++ b/src/ext/Dependency/dependency_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Dependency\WixToolsetTest.Dependency.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Dependency.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)dependency.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.dependency.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.dependency.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Dependency.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Dependency/test/WixToolsetTest.Dependency/DependencyExtensionFixture.cs b/src/ext/Dependency/test/WixToolsetTest.Dependency/DependencyExtensionFixture.cs
index 6190a4e0..ade2a12e 100644
--- a/src/ext/Dependency/test/WixToolsetTest.Dependency/DependencyExtensionFixture.cs
+++ b/src/ext/Dependency/test/WixToolsetTest.Dependency/DependencyExtensionFixture.cs
@@ -4,14 +4,15 @@ namespace WixToolsetTest.Dependency
 {
     using System.Linq;
     using System.Text.RegularExpressions;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.Dependency;
-    using Xunit;
 
+    [TestClass]
     public class DependencyExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingProvides()
         {
             var folder = TestData.Get(@"TestData\UsingProvides");
diff --git a/src/ext/Dependency/test/WixToolsetTest.Dependency/WixToolsetTest.Dependency.csproj b/src/ext/Dependency/test/WixToolsetTest.Dependency/WixToolsetTest.Dependency.csproj
index 70b56f45..1fd46c63 100644
--- a/src/ext/Dependency/test/WixToolsetTest.Dependency/WixToolsetTest.Dependency.csproj
+++ b/src/ext/Dependency/test/WixToolsetTest.Dependency/WixToolsetTest.Dependency.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/DirectX/directx.cmd b/src/ext/DirectX/directx.cmd
deleted file mode 100644
index 56889513..00000000
--- a/src/ext/DirectX/directx.cmd
+++ /dev/null
@@ -1,24 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo DirectX.wixext build %_C%
-
-:: Restore
-msbuild -t:Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Build
-msbuild -t:Build -p:Configuration=%_C% -tl -nologo -warnaserror test\WixToolsetTest.DirectX\WixToolsetTest.DirectX.csproj || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.DirectX || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror wixext\WixToolset.DirectX.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/DirectX/directx_t.proj b/src/ext/DirectX/directx_t.proj
new file mode 100644
index 00000000..17b147ef
--- /dev/null
+++ b/src/ext/DirectX/directx_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.DirectX\WixToolsetTest.DirectX.csproj" />
+    <ProjectReference Include="wixext\WixToolset.DirectX.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)directx.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.directx.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.directx.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.DirectX.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/DirectX/test/WixToolsetTest.DirectX/DirectXExtensionFixture.cs b/src/ext/DirectX/test/WixToolsetTest.DirectX/DirectXExtensionFixture.cs
index 64013ca6..dceaaec5 100644
--- a/src/ext/DirectX/test/WixToolsetTest.DirectX/DirectXExtensionFixture.cs
+++ b/src/ext/DirectX/test/WixToolsetTest.DirectX/DirectXExtensionFixture.cs
@@ -3,14 +3,15 @@
 namespace WixToolsetTest.DirectX
 {
     using System.Linq;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.DirectX;
-    using Xunit;
 
+    [TestClass]
     public class DirectXExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingPixelShaderVersion()
         {
             var folder = TestData.Get(@"TestData\UsingPixelShaderVersion");
diff --git a/src/ext/DirectX/test/WixToolsetTest.DirectX/WixToolsetTest.DirectX.csproj b/src/ext/DirectX/test/WixToolsetTest.DirectX/WixToolsetTest.DirectX.csproj
index 31a35320..c13f3300 100644
--- a/src/ext/DirectX/test/WixToolsetTest.DirectX/WixToolsetTest.DirectX.csproj
+++ b/src/ext/DirectX/test/WixToolsetTest.DirectX/WixToolsetTest.DirectX.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -19,6 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Firewall/firewall.cmd b/src/ext/Firewall/firewall.cmd
deleted file mode 100644
index 92926a8c..00000000
--- a/src/ext/Firewall/firewall.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo Firewall.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.Firewall || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.Firewall.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/Firewall/firewall_t.proj b/src/ext/Firewall/firewall_t.proj
new file mode 100644
index 00000000..67229c39
--- /dev/null
+++ b/src/ext/Firewall/firewall_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Firewall\WixToolsetTest.Firewall.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Firewall.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)firewall.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.firewall.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.firewall.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Firewall.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Firewall/test/WixToolsetTest.Firewall/FirewallExtensionFixture.cs b/src/ext/Firewall/test/WixToolsetTest.Firewall/FirewallExtensionFixture.cs
index 65016865..4b9aecd7 100644
--- a/src/ext/Firewall/test/WixToolsetTest.Firewall/FirewallExtensionFixture.cs
+++ b/src/ext/Firewall/test/WixToolsetTest.Firewall/FirewallExtensionFixture.cs
@@ -6,14 +6,15 @@ namespace WixToolsetTest.Firewall
     using System.IO;
     using System.Linq;
     using System.Xml.Linq;
-    using WixInternal.Core.TestPackage;
-    using WixInternal.TestSupport;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.Core.MSTestPackage;
+    using WixInternal.MSTestSupport;
     using WixToolset.Firewall;
-    using Xunit;
 
+    [TestClass]
     public class FirewallExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingFirewall()
         {
             var folder = TestData.Get(@"TestData\UsingFirewall");
@@ -52,7 +53,7 @@ namespace WixToolsetTest.Firewall
             }, results);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingFirewallARM64()
         {
             var folder = TestData.Get(@"TestData\UsingFirewall");
@@ -91,7 +92,7 @@ namespace WixToolsetTest.Firewall
             }, results);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithProperties()
         {
             var folder = TestData.Get(@"TestData\UsingProperties");
@@ -112,7 +113,7 @@ namespace WixToolsetTest.Firewall
             }, results);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithPropertiesUsingFirewallARM64()
         {
             var folder = TestData.Get(@"TestData\UsingProperties");
@@ -133,7 +134,7 @@ namespace WixToolsetTest.Firewall
             }, results);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanRoundtripFirewallExceptions()
         {
             var folder = TestData.Get(@"TestData", "UsingFirewall");
@@ -181,7 +182,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Select(a => a.Name).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanRoundtripFirewallExceptionsWithProperties()
         {
             var folder = TestData.Get(@"TestData", "UsingProperties");
@@ -212,7 +213,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Select(a => a.Name).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForApp()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ExampleApp");
@@ -230,7 +231,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForPort()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ExamplePort");
@@ -248,7 +249,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForDNSScope()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ExampleDNSScope");
@@ -264,7 +265,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForDHCPScope()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ExampleDHCPScope");
@@ -281,7 +282,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForWINSScope()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ExampleWINSScope");
@@ -298,7 +299,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForDefaultGatewayScope()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ExampleDefaultGatewayScope");
@@ -315,7 +316,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForINetFwRule3Values()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "INetFwRule3 values");
@@ -335,7 +336,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForINetFwRule3Properties()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "INetFwRule3 properties");
@@ -355,7 +356,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForGroupingValue()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "GroupingExample1");
@@ -370,7 +371,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForGroupingProperty()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "GroupingExample2");
@@ -386,7 +387,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForIcmpValue()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ICMPExample1");
@@ -401,7 +402,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForIcmpProperty()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "ICMPExample2");
@@ -416,7 +417,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForLocalScopeValue()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "LocalScopeExample1");
@@ -431,7 +432,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForLocalScopeProperty()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "LocalScopeExample2");
@@ -446,7 +447,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForRemotePorts()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "RemotePortExample1");
@@ -462,7 +463,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectForRemotePortsProperty()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "RemotePortExample2");
@@ -478,7 +479,7 @@ namespace WixToolsetTest.Firewall
             }, actual.Attributes);
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectWhenPropertiesAreUsed()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "[NAME]", "UsingProperties");
@@ -526,10 +527,10 @@ namespace WixToolsetTest.Firewall
                 });
 
             var nested = related.Select(e => e.Attributes().Single(a => a.Name.LocalName == "Name").Value);
-            Assert.False(nested.Any());
+            Assert.IsFalse(nested.Any());
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectWhenNestedPropertiesAreUsed()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "Single Nested properties", "UsingProperties");
@@ -559,10 +560,10 @@ namespace WixToolsetTest.Firewall
                 });
 
             var nested = related.Select(e => e.Attributes().Single(a => a.Name.LocalName == "Name").Value);
-            Assert.False(nested.Any());
+            Assert.IsFalse(nested.Any());
         }
 
-        [Fact]
+        [TestMethod]
         public void RoundtripAttributesAreCorrectWhenMultipleNestedPropertiesAreUsed()
         {
             var actual = BuildAndDecompileAndBuild("http://wixtoolset.org/schemas/v4/wxs/firewall", "Multiple Nested properties", "UsingProperties");
diff --git a/src/ext/Firewall/test/WixToolsetTest.Firewall/WixToolsetTest.Firewall.csproj b/src/ext/Firewall/test/WixToolsetTest.Firewall/WixToolsetTest.Firewall.csproj
index e46020a6..5de88c8b 100644
--- a/src/ext/Firewall/test/WixToolsetTest.Firewall/WixToolsetTest.Firewall.csproj
+++ b/src/ext/Firewall/test/WixToolsetTest.Firewall/WixToolsetTest.Firewall.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Http/http.cmd b/src/ext/Http/http.cmd
deleted file mode 100644
index afcffb24..00000000
--- a/src/ext/Http/http.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo Http.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.Http || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.Http.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/Http/http_t.proj b/src/ext/Http/http_t.proj
new file mode 100644
index 00000000..8cd9c7d4
--- /dev/null
+++ b/src/ext/Http/http_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Http\WixToolsetTest.Http.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Http.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)http.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.http.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.http.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Http.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Http/test/WixToolsetTest.Http/HttpExtensionFixture.cs b/src/ext/Http/test/WixToolsetTest.Http/HttpExtensionFixture.cs
index ffd698f5..c91ce937 100644
--- a/src/ext/Http/test/WixToolsetTest.Http/HttpExtensionFixture.cs
+++ b/src/ext/Http/test/WixToolsetTest.Http/HttpExtensionFixture.cs
@@ -2,14 +2,15 @@
 
 namespace WixToolsetTest.Http
 {
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.Http;
-    using Xunit;
 
+    [TestClass]
     public class HttpExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingSsl()
         {
             var folder = TestData.Get("TestData", "Ssl");
@@ -29,7 +30,7 @@ namespace WixToolsetTest.Http
             }, results);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingUrlReservation()
         {
             var folder = TestData.Get(@"TestData\UsingUrlReservation");
diff --git a/src/ext/Http/test/WixToolsetTest.Http/WixToolsetTest.Http.csproj b/src/ext/Http/test/WixToolsetTest.Http/WixToolsetTest.Http.csproj
index b23ef481..d5e6c929 100644
--- a/src/ext/Http/test/WixToolsetTest.Http/WixToolsetTest.Http.csproj
+++ b/src/ext/Http/test/WixToolsetTest.Http/WixToolsetTest.Http.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Iis/iis.cmd b/src/ext/Iis/iis.cmd
deleted file mode 100644
index 0ae87a77..00000000
--- a/src/ext/Iis/iis.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo Iis.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test test\WixToolsetTest.Iis -c %_C% --no-build --nologo || exit /b
-
-:: Pack
-dotnet pack wixext\WixToolset.Iis.wixext.csproj -c %_C% --no-build --nologo || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/Iis/iis_t.proj b/src/ext/Iis/iis_t.proj
new file mode 100644
index 00000000..84473475
--- /dev/null
+++ b/src/ext/Iis/iis_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Iis\WixToolsetTest.Iis.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Iis.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)iis.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.iis.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.iis.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Iis.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Iis/test/WixToolsetTest.Iis/IisExtensionFixture.cs b/src/ext/Iis/test/WixToolsetTest.Iis/IisExtensionFixture.cs
index ab3f35d9..01a89dc0 100644
--- a/src/ext/Iis/test/WixToolsetTest.Iis/IisExtensionFixture.cs
+++ b/src/ext/Iis/test/WixToolsetTest.Iis/IisExtensionFixture.cs
@@ -3,14 +3,15 @@
 namespace WixToolsetTest.Iis
 {
     using System.Linq;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.Iis;
-    using Xunit;
 
+    [TestClass]
     public class IisExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingIIs()
         {
             var folder = TestData.Get(@"TestData\UsingIis");
diff --git a/src/ext/Iis/test/WixToolsetTest.Iis/WixToolsetTest.Iis.csproj b/src/ext/Iis/test/WixToolsetTest.Iis/WixToolsetTest.Iis.csproj
index a39e5b0b..a0a6e043 100644
--- a/src/ext/Iis/test/WixToolsetTest.Iis/WixToolsetTest.Iis.csproj
+++ b/src/ext/Iis/test/WixToolsetTest.Iis/WixToolsetTest.Iis.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -19,6 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Msmq/msmq.cmd b/src/ext/Msmq/msmq.cmd
deleted file mode 100644
index 3ebceab4..00000000
--- a/src/ext/Msmq/msmq.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo Msmq.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test test\WixToolsetTest.Msmq -c %_C% --no-build --nologo || exit /b
-
-:: Pack
-dotnet pack wixext\WixToolset.Msmq.wixext.csproj -c %_C% --no-build --nologo || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/Msmq/msmq_t.proj b/src/ext/Msmq/msmq_t.proj
new file mode 100644
index 00000000..73424370
--- /dev/null
+++ b/src/ext/Msmq/msmq_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Msmq\WixToolsetTest.Msmq.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Msmq.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)Msmq.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.Msmq.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.Msmq.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Msmq.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Msmq/test/WixToolsetTest.Msmq/MsmqExtensionFixture.cs b/src/ext/Msmq/test/WixToolsetTest.Msmq/MsmqExtensionFixture.cs
index 970bc2e9..60335b8a 100644
--- a/src/ext/Msmq/test/WixToolsetTest.Msmq/MsmqExtensionFixture.cs
+++ b/src/ext/Msmq/test/WixToolsetTest.Msmq/MsmqExtensionFixture.cs
@@ -6,14 +6,15 @@ namespace WixToolsetTest.Msmq
     using System.IO;
     using System.Linq;
     using System.Xml.Linq;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.Msmq;
-    using Xunit;
 
+    [TestClass]
     public class MsmqExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingMessageQueue()
         {
             var folder = TestData.Get(@"TestData\UsingMessageQueue");
@@ -36,7 +37,8 @@ namespace WixToolsetTest.Msmq
             }, results);
         }
 
-        [Fact(Skip = "Util:Wix4Group and Util:Wix6Group decompilation issues prevent this usage currently")]
+        [TestMethod]
+        [Ignore("Util:Wix4Group and Util:Wix6Group decompilation issues prevent this usage currently")]
         public void CanRoundtripMessageQueue()
         {
             var folder = TestData.Get(@"TestData\UsingMessageQueue");
diff --git a/src/ext/Msmq/test/WixToolsetTest.Msmq/WixToolsetTest.Msmq.csproj b/src/ext/Msmq/test/WixToolsetTest.Msmq/WixToolsetTest.Msmq.csproj
index e7b6f21e..a8991c2e 100644
--- a/src/ext/Msmq/test/WixToolsetTest.Msmq/WixToolsetTest.Msmq.csproj
+++ b/src/ext/Msmq/test/WixToolsetTest.Msmq/WixToolsetTest.Msmq.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -19,6 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/NetFx/netfx.cmd b/src/ext/NetFx/netfx.cmd
deleted file mode 100644
index d81959cc..00000000
--- a/src/ext/NetFx/netfx.cmd
+++ /dev/null
@@ -1,48 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-@set _L=%~dp0..\..\..\build\logs
-
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if /i "%1"=="inc" set _INC=1
-@if /i "%1"=="clean" set _CLEAN=1
-@if not "%1"=="" shift & goto parse_args
-
-@set _B=%~dp0..\..\..\build\NetFx.wixext\%_C%
-
-:: Clean
-
-@if "%_INC%"=="" call :clean
-@if NOT "%_CLEAN%"=="" goto :end
-
-@echo NetFx.wixext build %_C%
-
-:: Restore
-nuget restore netcoresearch\packages.config || exit /b
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror -bl:%_L%\ext_netfx_build.binlog || exit /b
-
-:: Test
-dotnet test ^
- %_B%\net6.0\WixToolsetTest.NetFx.dll ^
- --nologo -l "trx;LogFileName=%_L%\TestResults\netfx.wixext.trx" || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.Netfx.wixext.csproj || exit /b
-
-@goto :end
-
-:clean
-@rd /s/q "..\..\build\NetFx.wixext" 2> nul
-@del "..\..\build\artifacts\WixToolset.NetFx.wixext.*.nupkg" 2> nul
-@del "%_L%\ext_netfx_build.binlog" 2> nul
-@del "%_L%\TestResults\netfx.wixext.trx" 2> nul
-@rd /s/q "%USERPROFILE%\.nuget\packages\wixtoolset.netfx.wixext" 2> nul
-@exit /b
-
-:end
-@popd
-@endlocal
diff --git a/src/ext/NetFx/netfx_t.proj b/src/ext/NetFx/netfx_t.proj
new file mode 100644
index 00000000..3301dc8a
--- /dev/null
+++ b/src/ext/NetFx/netfx_t.proj
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="wixlib\netfx.wixproj" />
+    <ProjectReference Include="test\WixToolsetTest.Netfx\WixToolsetTest.Netfx.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Netfx.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <!--
+    This should work but at first glance, the .vcxproj doesn't get detected as a "package.config-style project."
+    Worth finding out if we could trigger it artificially. It would let us stop needing nuget.exe.
+
+    <ProjectReference Include="netcoresearch\netcoresearch.vcxproj" Targets="Restore" Properties="RestorePackagesConfig=true" />
+    -->
+    <Exec Command="nuget restore netcoresearch\packages.config" />
+
+    <RemoveDir Directories="$(RootBuildFolder)NetFx.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.netfx.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.netfx.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.NetFx.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/NetFx/test/WixToolsetTest.Netfx/NetfxExtensionFixture.cs b/src/ext/NetFx/test/WixToolsetTest.Netfx/NetfxExtensionFixture.cs
index a78a5617..37f715bf 100644
--- a/src/ext/NetFx/test/WixToolsetTest.Netfx/NetfxExtensionFixture.cs
+++ b/src/ext/NetFx/test/WixToolsetTest.Netfx/NetfxExtensionFixture.cs
@@ -4,14 +4,15 @@ namespace WixToolsetTest.Netfx
 {
     using System.IO;
     using System.Linq;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.Netfx;
-    using Xunit;
 
+    [TestClass]
     public class NetfxExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingLatestDotNetCorePackages()
         {
             using (var fs = new DisposableFileSystem())
@@ -21,30 +22,24 @@ namespace WixToolsetTest.Netfx
                 var bundleSourceFolder = TestData.Get(@"TestData\UsingDotNetCorePackages");
                 var intermediateFolder = Path.Combine(baseFolder, "obj");
 
-                var extensionResult = WixRunner.Execute(new[]
-                {
-                    "extension", "add",
-                    "WixToolset.BootstrapperApplications.wixext"
-                });
-
                 var compileResult = WixRunner.Execute(new[]
                 {
                     "build",
                     Path.Combine(bundleSourceFolder, "BundleLatest.wxs"),
                     Path.Combine(bundleSourceFolder, "NetCore3.1.12_x86.wxs"),
                     Path.Combine(bundleSourceFolder, "NetCore3.1.12_x64.wxs"),
-                    "-ext", "WixToolset.BootstrapperApplications.wixext",
+                    "-ext", TestData.Get(@"WixToolset.BootstrapperApplications.wixext.dll").Replace("NetFx.wixext", "Bal.wixext"),
                     "-ext", TestData.Get(@"WixToolset.Netfx.wixext.dll"),
                     "-intermediateFolder", intermediateFolder,
                     "-o", bundleFile,
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingLatestDotNetCorePackages_X64()
         {
             using (var fs = new DisposableFileSystem())
@@ -54,29 +49,23 @@ namespace WixToolsetTest.Netfx
                 var bundleSourceFolder = TestData.Get(@"TestData\UsingDotNetCorePackages");
                 var intermediateFolder = Path.Combine(baseFolder, "obj");
 
-                var extensionResult = WixRunner.Execute(new[]
-                {
-                    "extension", "add",
-                    "WixToolset.BootstrapperApplications.wixext"
-                });
-
                 var compileResult = WixRunner.Execute(new[]
                 {
                     "build",
                     Path.Combine(bundleSourceFolder, "BundleLatest_x64.wxs"),
                     Path.Combine(bundleSourceFolder, "NetCore3.1.12_x64.wxs"),
-                    "-ext", "WixToolset.BootstrapperApplications.wixext",
+                    "-ext", TestData.Get(@"WixToolset.BootstrapperApplications.wixext.dll").Replace("NetFx.wixext", "Bal.wixext"),
                     "-ext", TestData.Get(@"WixToolset.Netfx.wixext.dll"),
                     "-intermediateFolder", intermediateFolder,
                     "-o", bundleFile,
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingNetFx481Packages()
         {
             using (var fs = new DisposableFileSystem())
@@ -86,17 +75,11 @@ namespace WixToolsetTest.Netfx
                 var bundleSourceFolder = TestData.Get(@"TestData\UsingNetFxPackages");
                 var intermediateFolder = Path.Combine(baseFolder, "obj");
 
-                var extensionResult = WixRunner.Execute(new[]
-                {
-                    "extension", "add",
-                    "WixToolset.BootstrapperApplications.wixext"
-                });
-
                 var compileResult = WixRunner.Execute(new[]
                 {
                     "build",
                     Path.Combine(bundleSourceFolder, "BundleLatest.wxs"),
-                    "-ext", "WixToolset.BootstrapperApplications.wixext",
+                    "-ext", TestData.Get(@"WixToolset.BootstrapperApplications.wixext.dll").Replace("NetFx.wixext", "Bal.wixext"),
                     "-ext", TestData.Get(@"WixToolset.Netfx.wixext.dll"),
                     "-intermediateFolder", intermediateFolder,
                     "-o", bundleFile,
@@ -104,11 +87,11 @@ namespace WixToolsetTest.Netfx
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingNetFxSearches()
         {
             using (var fs = new DisposableFileSystem())
@@ -118,20 +101,12 @@ namespace WixToolsetTest.Netfx
                 var bundleSourceFolder = TestData.Get(@"TestData\UsingNetFxSearches");
                 var intermediateFolder = Path.Combine(baseFolder, "obj");
 
-                var extensionResult = WixRunner.Execute(warningsAsErrors: true, new[]
-                {
-                    "extension", "add",
-                    "WixToolset.BootstrapperApplications.wixext",
-                    "extension", "add",
-                    "WixToolset.Util.wixext",
-                });
-
                 var compileResult = WixRunner.Execute(new[]
                 {
                     "build",
                     Path.Combine(bundleSourceFolder, "BundleLatest.wxs"),
-                    "-ext", "WixToolset.BootstrapperApplications.wixext",
-                    "-ext", "WixToolset.Util.wixext",
+                    "-ext", TestData.Get(@"WixToolset.BootstrapperApplications.wixext.dll").Replace("NetFx.wixext", "Bal.wixext"),
+                    "-ext", TestData.Get(@"WixToolset.Util.wixext.dll").Replace("NetFx.wixext", "Util.wixext"),
                     "-ext", TestData.Get(@"WixToolset.Netfx.wixext.dll"),
                     "-intermediateFolder", intermediateFolder,
                     "-o", bundleFile,
@@ -139,11 +114,11 @@ namespace WixToolsetTest.Netfx
                 });
                 compileResult.AssertSuccess();
 
-                Assert.True(File.Exists(bundleFile));
+                Assert.IsTrue(File.Exists(bundleFile));
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingNativeImage()
         {
             var folder = TestData.Get(@"TestData\UsingNativeImage");
@@ -162,7 +137,7 @@ namespace WixToolsetTest.Netfx
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingNativeImageX64()
         {
             var folder = TestData.Get(@"TestData\UsingNativeImage");
@@ -181,7 +156,7 @@ namespace WixToolsetTest.Netfx
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingNativeImageARM64()
         {
             var folder = TestData.Get(@"TestData\UsingNativeImage");
@@ -200,7 +175,7 @@ namespace WixToolsetTest.Netfx
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingDotNetCompatibilityCheck()
         {
             var folder = TestData.Get(@"TestData\UsingDotNetCompatibilityCheck");
diff --git a/src/ext/NetFx/test/WixToolsetTest.Netfx/WixToolsetTest.Netfx.csproj b/src/ext/NetFx/test/WixToolsetTest.Netfx/WixToolsetTest.Netfx.csproj
index 4e509cce..bdca49e6 100644
--- a/src/ext/NetFx/test/WixToolsetTest.Netfx/WixToolsetTest.Netfx.csproj
+++ b/src/ext/NetFx/test/WixToolsetTest.Netfx/WixToolsetTest.Netfx.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/PowerShell/powershell_t.proj b/src/ext/PowerShell/powershell_t.proj
new file mode 100644
index 00000000..da54d629
--- /dev/null
+++ b/src/ext/PowerShell/powershell_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.PowerShell\WixToolsetTest.Powershell.csproj" />
+    <ProjectReference Include="wixext\WixToolset.PowerShell.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)PowerShell.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.PowerShell.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.PowerShell.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.PowerShell.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/PowerShell/ps.cmd b/src/ext/PowerShell/ps.cmd
deleted file mode 100644
index 4a8aa61e..00000000
--- a/src/ext/PowerShell/ps.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo PowerShell.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.PowerShell || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.PowerShell.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/PowerShell/test/WixToolsetTest.PowerShell/PowerShellExtensionFixture.cs b/src/ext/PowerShell/test/WixToolsetTest.PowerShell/PowerShellExtensionFixture.cs
index eafda99f..a1dc3282 100644
--- a/src/ext/PowerShell/test/WixToolsetTest.PowerShell/PowerShellExtensionFixture.cs
+++ b/src/ext/PowerShell/test/WixToolsetTest.PowerShell/PowerShellExtensionFixture.cs
@@ -2,14 +2,15 @@
 
 namespace WixToolsetTest.PowerShell
 {
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.PowerShell;
-    using Xunit;
 
+    [TestClass]
     public class PowerShellExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CantBuildUsingTypesFileWithoutSnapIn()
         {
             var folder = TestData.Get(@"TestData\TypesFile");
@@ -19,8 +20,8 @@ namespace WixToolsetTest.PowerShell
             var results = build.BuildAndQuery(args => {
                 wixRunnerResult = WixRunner.Execute(args);
             });
-            Assert.NotNull(wixRunnerResult);
-            Assert.Equal((int)PSErrors.Ids.NeitherIdSpecified, wixRunnerResult.ExitCode);
+            Assert.IsNotNull(wixRunnerResult);
+            Assert.AreEqual((int)PSErrors.Ids.NeitherIdSpecified, wixRunnerResult.ExitCode);
         }
     }
 }
diff --git a/src/ext/PowerShell/test/WixToolsetTest.PowerShell/WixToolsetTest.Powershell.csproj b/src/ext/PowerShell/test/WixToolsetTest.PowerShell/WixToolsetTest.Powershell.csproj
index 347ca1ed..cff13cb7 100644
--- a/src/ext/PowerShell/test/WixToolsetTest.PowerShell/WixToolsetTest.Powershell.csproj
+++ b/src/ext/PowerShell/test/WixToolsetTest.PowerShell/WixToolsetTest.Powershell.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Sql/sql.cmd b/src/ext/Sql/sql.cmd
deleted file mode 100644
index 41af0223..00000000
--- a/src/ext/Sql/sql.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo Sql.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.Sql || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.Sql.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/Sql/sql_t.proj b/src/ext/Sql/sql_t.proj
new file mode 100644
index 00000000..97b2c8fd
--- /dev/null
+++ b/src/ext/Sql/sql_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Sql\WixToolsetTest.Sql.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Sql.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)Sql.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.Sql.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.Sql.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Sql.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Sql/test/WixToolsetTest.Sql/SqlExtensionFixture.cs b/src/ext/Sql/test/WixToolsetTest.Sql/SqlExtensionFixture.cs
index 5576576d..14ca14c3 100644
--- a/src/ext/Sql/test/WixToolsetTest.Sql/SqlExtensionFixture.cs
+++ b/src/ext/Sql/test/WixToolsetTest.Sql/SqlExtensionFixture.cs
@@ -3,14 +3,15 @@
 namespace WixToolsetTest.Sql
 {
     using System.Linq;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.Sql;
-    using Xunit;
 
+    [TestClass]
     public class SqlExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingSqlStuff()
         {
             var folder = TestData.Get(@"TestData\UsingSql");
diff --git a/src/ext/Sql/test/WixToolsetTest.Sql/WixToolsetTest.Sql.csproj b/src/ext/Sql/test/WixToolsetTest.Sql/WixToolsetTest.Sql.csproj
index 6c848683..62345258 100644
--- a/src/ext/Sql/test/WixToolsetTest.Sql/WixToolsetTest.Sql.csproj
+++ b/src/ext/Sql/test/WixToolsetTest.Sql/WixToolsetTest.Sql.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/UI/test/WixToolsetTest.UI/UIExtensionFixture.cs b/src/ext/UI/test/WixToolsetTest.UI/UIExtensionFixture.cs
index bb20f087..e06feac7 100644
--- a/src/ext/UI/test/WixToolsetTest.UI/UIExtensionFixture.cs
+++ b/src/ext/UI/test/WixToolsetTest.UI/UIExtensionFixture.cs
@@ -4,15 +4,16 @@ namespace WixToolsetTest.UI
 {
     using System.IO;
     using System.Linq;
-    using WixInternal.Core.TestPackage;
-    using WixInternal.TestSupport;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.Core.MSTestPackage;
+    using WixInternal.MSTestSupport;
     using WixToolset.Data.WindowsInstaller;
     using WixToolset.UI;
-    using Xunit;
 
+    [TestClass]
     public class UIExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIAdvanced()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Advanced");
@@ -20,7 +21,7 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(Build, "Binary", "Dialog", "CustomAction", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:AdvancedWelcomeEulaDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:AdvancedWelcomeEulaDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -37,7 +38,7 @@ namespace WixToolsetTest.UI
                 "CustomAction:WixSetPerMachineFolder\t51\tAPPLICATIONFOLDER\t[WixPerMachineFolder]\t",
                 "CustomAction:WixSetPerUserFolder\t51\tAPPLICATIONFOLDER\t[WixPerUserFolder]\t",
             }, results.Where(r => r.StartsWith("CustomAction:")).ToArray());
-            Assert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).ToArray());
+            WixAssert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).ToArray());
             WixAssert.CompareLineByLine(new[]
             {
                 "InstallUISequence:AdvancedWelcomeEulaDlg\tNOT Installed\t1297",
@@ -45,7 +46,7 @@ namespace WixToolsetTest.UI
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIAdvancedX64()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Advanced");
@@ -53,7 +54,7 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(BuildX64, "Binary", "Dialog", "CustomAction", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:AdvancedWelcomeEulaDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:AdvancedWelcomeEulaDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -70,10 +71,10 @@ namespace WixToolsetTest.UI
                 "CustomAction:WixSetPerMachineFolder\t51\tAPPLICATIONFOLDER\t[WixPerMachineFolder]\t",
                 "CustomAction:WixSetPerUserFolder\t51\tAPPLICATIONFOLDER\t[WixPerUserFolder]\t",
             }, results.Where(r => r.StartsWith("CustomAction:")).ToArray());
-            Assert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).ToArray());
+            WixAssert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIAdvancedARM64()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Advanced");
@@ -81,7 +82,7 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(BuildARM64, "Binary", "Dialog", "CustomAction", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:AdvancedWelcomeEulaDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:AdvancedWelcomeEulaDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -98,10 +99,10 @@ namespace WixToolsetTest.UI
                 "CustomAction:WixSetPerMachineFolder\t51\tAPPLICATIONFOLDER\t[WixPerMachineFolder]\t",
                 "CustomAction:WixSetPerUserFolder\t51\tAPPLICATIONFOLDER\t[WixPerUserFolder]\t",
             }, results.Where(r => r.StartsWith("CustomAction:")).ToArray());
-            Assert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).ToArray());
+            WixAssert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIFeatureTree()
         {
             var folder = TestData.Get(@"TestData", "WixUI_FeatureTree");
@@ -109,9 +110,9 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(BuildX64, "Binary", "Dialog", "CustomAction", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:WelcomeDlg\t"));
-            Assert.Single(results, result => result.StartsWith("Dialog:CustomizeDlg\t"));
-            Assert.Empty(results.Where(result => result.StartsWith("Dialog:SetupTypeDlg\t")));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:WelcomeDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:CustomizeDlg\t"));
+            WixAssert.Empty(results.Where(result => result.StartsWith("Dialog:SetupTypeDlg\t")));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -125,14 +126,14 @@ namespace WixToolsetTest.UI
             {
                 "CustomAction:SetWIXUI_EXITDIALOGOPTIONALTEXT\t51\tWIXUI_EXITDIALOGOPTIONALTEXT\tThank you for installing [ProductName].\t",
             }, results.Where(r => r.StartsWith("CustomAction:")).ToArray());
-            Assert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")));
+            WixAssert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")));
             WixAssert.CompareLineByLine(new[]
             {
                 "InstallUISequence:WelcomeDlg\tNOT Installed OR PATCH\t1297",
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithWixUIInstallDirWithCustomizedEula()
         {
             var folder = TestData.Get(@"TestData", "WixUI_InstallDir");
@@ -140,8 +141,8 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(BuildEula, "Binary", "Dialog", "CustomAction", "Property", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:InstallDirDlg\t"));
-            Assert.Single(results, result => result.StartsWith("Dialog:WelcomeDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:InstallDirDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:WelcomeDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -171,7 +172,7 @@ namespace WixToolsetTest.UI
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIMinimal()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Minimal");
@@ -179,7 +180,7 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(Build, "Binary", "Dialog", "CustomAction", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:WelcomeEulaDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:WelcomeEulaDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -189,8 +190,8 @@ namespace WixToolsetTest.UI
                 "Binary:WixUI_Ico_Exclam\t[Binary data]",
                 "Binary:WixUI_Ico_Info\t[Binary data]",
             }, results.Where(r => r.StartsWith("Binary:")).ToArray());
-            Assert.Empty(results.Where(r => r.StartsWith("CustomAction:")));
-            Assert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")));
+            WixAssert.Empty(results.Where(r => r.StartsWith("CustomAction:")));
+            WixAssert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")));
             WixAssert.CompareLineByLine(new[]
             {
                 "InstallUISequence:WelcomeDlg\tInstalled AND PATCH\t1296",
@@ -198,7 +199,7 @@ namespace WixToolsetTest.UI
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIMinimalInKazakh()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Minimal");
@@ -207,10 +208,10 @@ namespace WixToolsetTest.UI
 
             var results = build.BuildAndQuery(BuildInKazakh, "Dialog");
             var welcomeDlg = results.Where(r => r.StartsWith("Dialog:WelcomeDlg\t")).Select(r => r.Split('\t')).Single();
-            Assert.Equal("[ProductName] бағдарламасын орнату", welcomeDlg[6]);
+            Assert.AreEqual("[ProductName] бағдарламасын орнату", welcomeDlg[6]);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIMinimalAndReadPdb()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Minimal");
@@ -236,7 +237,7 @@ namespace WixToolsetTest.UI
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIMondo()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Mondo");
@@ -244,9 +245,9 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(Build, "Binary", "Dialog", "CustomAction", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:WelcomeDlg\t"));
-            Assert.Single(results, result => result.StartsWith("Dialog:CustomizeDlg\t"));
-            Assert.Single(results, result => result.StartsWith("Dialog:SetupTypeDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:WelcomeDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:CustomizeDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:SetupTypeDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -271,7 +272,7 @@ namespace WixToolsetTest.UI
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingWixUIMondoLocalized()
         {
             var folder = TestData.Get(@"TestData", "WixUI_Mondo");
@@ -285,7 +286,7 @@ namespace WixToolsetTest.UI
             }, results.Where(s => s.StartsWith("Control:ErrorDlg\tY")).Select(s => s.Split('\t')[9]).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithInstallDirAndRemovedDialog()
         {
             var folder = TestData.Get(@"TestData", "InstallDir_NoLicense");
@@ -293,7 +294,7 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(Build, "Binary", "Dialog", "CustomAction", "Property", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:InstallDirDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:InstallDirDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -318,7 +319,7 @@ namespace WixToolsetTest.UI
                 "ControlEvent:InstallDirDlg\tNext\tDoAction\tWixUIValidatePath_X86\t1\t2",
             }, results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).OrderBy(s => s).ToArray());
 
-            Assert.Empty(results.Where(result => result.Contains("LicenseAgreementDlg")).ToArray());
+            WixAssert.Empty(results.Where(result => result.Contains("LicenseAgreementDlg")).ToArray());
 
             WixAssert.CompareLineByLine(new[]
             {
@@ -326,7 +327,7 @@ namespace WixToolsetTest.UI
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithInstallDirAndAddedDialog()
         {
             var folder = TestData.Get(@"TestData", "InstallDir_SpecialDlg");
@@ -334,7 +335,7 @@ namespace WixToolsetTest.UI
             var build = new Builder(folder, typeof(UIExtensionFactory), new[] { bindFolder });
 
             var results = build.BuildAndQuery(BuildX64, "Binary", "Control", "Dialog", "CustomAction", "Property", "ControlEvent", "InstallUISequence");
-            Assert.Single(results, result => result.StartsWith("Dialog:InstallDirDlg\t"));
+            WixAssert.Single(results, result => result.StartsWith("Dialog:InstallDirDlg\t"));
             WixAssert.CompareLineByLine(new[]
             {
                 "Binary:WixUI_Bmp_Banner\t[Binary data]",
@@ -344,23 +345,23 @@ namespace WixToolsetTest.UI
                 "Binary:WixUI_Ico_Exclam\t[Binary data]",
                 "Binary:WixUI_Ico_Info\t[Binary data]",
             }, results.Where(r => r.StartsWith("Binary:")).ToArray());
-            Assert.Empty(results.Where(r => r.StartsWith("CustomAction:")).ToArray());
+            WixAssert.Empty(results.Where(r => r.StartsWith("CustomAction:")).ToArray());
             WixAssert.CompareLineByLine(new[]
             {
                 "Property:WIXUI_INSTALLDIR\tINSTALLFOLDER",
             }, results.Where(r => r.StartsWith("Property:WIXUI")).ToArray());
-            Assert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).OrderBy(s => s).ToArray());
+            WixAssert.Empty(results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("DoAction")).OrderBy(s => s).ToArray());
             WixAssert.CompareLineByLine(new[]
             {
                 "InstallUISequence:WelcomeDlg\tNOT Installed OR PATCH\t1297",
             }, results.Where(r => r.StartsWith("InstallUISequence:AdvancedWelcome") || r.StartsWith("InstallUISequence:Welcome")).ToArray());
 
-            Assert.Equal(10, results.Where(result => result.StartsWith("Control:") && result.Contains("SpecialDlg")).Count());
-            Assert.Equal(5, results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("SpecialDlg")).Count());
-            Assert.Single(results.Where(result => result.StartsWith("Dialog:") && result.Contains("SpecialDlg")));
+            Assert.AreEqual(10, results.Where(result => result.StartsWith("Control:") && result.Contains("SpecialDlg")).Count());
+            Assert.AreEqual(5, results.Where(result => result.StartsWith("ControlEvent:") && result.Contains("SpecialDlg")).Count());
+            WixAssert.Single(results.Where(result => result.StartsWith("Dialog:") && result.Contains("SpecialDlg")));
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildWithV3LikeUIRef()
         {
             var folder = TestData.Get(@"TestData", "InvalidUIRef");
@@ -381,7 +382,7 @@ namespace WixToolsetTest.UI
 
                 var results = WixRunner.Execute(args);
                 var message = results.Messages.Single();
-                Assert.Equal("The identifier 'WixUI:WixUI_Mondo' is inaccessible due to its protection level.", message.ToString());
+                Assert.AreEqual("The identifier 'WixUI:WixUI_Mondo' is inaccessible due to its protection level.", message.ToString());
             }
         }
 
diff --git a/src/ext/UI/test/WixToolsetTest.UI/WixToolsetTest.UI.csproj b/src/ext/UI/test/WixToolsetTest.UI/WixToolsetTest.UI.csproj
index 675f14f8..132920c5 100644
--- a/src/ext/UI/test/WixToolsetTest.UI/WixToolsetTest.UI.csproj
+++ b/src/ext/UI/test/WixToolsetTest.UI/WixToolsetTest.UI.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/UI/ui.cmd b/src/ext/UI/ui.cmd
deleted file mode 100644
index a990db91..00000000
--- a/src/ext/UI/ui.cmd
+++ /dev/null
@@ -1,42 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-@set _L=%~dp0..\..\..\build\logs
-
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if /i "%1"=="inc" set _INC=1
-@if /i "%1"=="clean" set _CLEAN=1
-@if not "%1"=="" shift & goto parse_args
-
-@set _B=%~dp0..\..\..\build\UI.wixext\%_C%
-
-:: Clean
-
-@if "%_INC%"=="" call :clean
-@if NOT "%_CLEAN%"=="" goto :end
-
-@echo UI.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror -bl:%_L%\ext_ui_build.binlog || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.UI || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.UI.wixext.csproj || exit /b
-
-@goto :end
-
-:clean
-@rd /s/q "..\..\..\build\UI.wixext" 2> nul
-@del "..\..\..\build\artifacts\WixToolset.UI.wixext.*.nupkg" 2> nul
-@del "%_L%\ext_ui_build.binlog" 2> nul
-@rd /s/q "%USERPROFILE%\.nuget\packages\wixtoolset.ui.wixext" 2> nul
-@exit /b
-
-:end
-@popd
-@endlocal
diff --git a/src/ext/UI/ui_t.proj b/src/ext/UI/ui_t.proj
new file mode 100644
index 00000000..0a989b6f
--- /dev/null
+++ b/src/ext/UI/ui_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.UI\WixToolsetTest.UI.csproj" />
+    <ProjectReference Include="wixext\WixToolset.UI.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)UI.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.UI.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.UI.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.UI.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/Util/test/WixToolsetTest.Util/UtilExtensionFixture.cs b/src/ext/Util/test/WixToolsetTest.Util/UtilExtensionFixture.cs
index 13c39091..03d87e4e 100644
--- a/src/ext/Util/test/WixToolsetTest.Util/UtilExtensionFixture.cs
+++ b/src/ext/Util/test/WixToolsetTest.Util/UtilExtensionFixture.cs
@@ -2,19 +2,20 @@
 
 namespace WixToolsetTest.Util
 {
+    using System;
     using System.IO;
     using System.Linq;
     using System.Xml;
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
-    using WixToolset.Util;
-    using Xunit;
     using System.Xml.Linq;
-    using System;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
+    using WixToolset.Util;
 
+    [TestClass]
     public class UtilExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingFileShare()
         {
             var folder = TestData.Get(@"TestData\UsingFileShare");
@@ -35,7 +36,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingFileShareX64()
         {
             var folder = TestData.Get(@"TestData\UsingFileShare");
@@ -56,7 +57,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanRoundtripFileShare()
         {
             var folder = TestData.Get(@"TestData", "UsingFileShare");
@@ -79,7 +80,7 @@ namespace WixToolsetTest.Util
             }, utilElementNames);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildCloseApplication()
         {
             var folder = TestData.Get(@"TestData\CloseApplication");
@@ -96,7 +97,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildInternetShortcutInProduct()
         {
             var folder = TestData.Get(@"TestData\InternetShortcut");
@@ -116,7 +117,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildInternetShortcutInMergeModule()
         {
             var folder = TestData.Get(@"TestData\InternetShortcutModule");
@@ -136,7 +137,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithPermissionEx()
         {
             var folder = TestData.Get(@"TestData\PermissionEx");
@@ -153,7 +154,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildRemoveRegistryKeyExInMergeModule()
         {
             var folder = TestData.Get(@"TestData", "RemoveRegistryKeyEx");
@@ -168,7 +169,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildRemoveFolderExInMergeModule()
         {
             var folder = TestData.Get(@"TestData\RemoveFolderEx");
@@ -183,7 +184,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildRemoveFolderExInPackage()
         {
             var folder = TestData.Get(@"TestData\RemoveFolderExPackage");
@@ -198,7 +199,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildServiceConfig()
         {
             var folder = TestData.Get(@"TestData", "ServiceConfig");
@@ -215,7 +216,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithEventManifest()
         {
             var folder = TestData.Get(@"TestData\EventManifest");
@@ -240,7 +241,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithQueries()
         {
             var folder = TestData.Get(@"TestData\Queries");
@@ -259,7 +260,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildAndDecompiileQueries()
         {
             var folder = TestData.Get(@"TestData\Queries");
@@ -285,7 +286,7 @@ namespace WixToolsetTest.Util
             }, utilElementNames);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildWithXmlConfig()
         {
             var folder = TestData.Get(@"TestData", "XmlConfig");
@@ -301,7 +302,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanRoundtripXmlConfig()
         {
             var folder = TestData.Get(@"TestData", "XmlConfig");
@@ -324,7 +325,7 @@ namespace WixToolsetTest.Util
             }, utilElementNames);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildModuleWithXmlConfig()
         {
             var folder = TestData.Get(@"TestData", "XmlConfigModule");
@@ -338,7 +339,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildBundleWithSearches()
         {
             var folder = TestData.Get(@"TestData\BundleWithSearches");
@@ -366,15 +367,15 @@ namespace WixToolsetTest.Util
 
                 result.AssertSuccess();
 
-                Assert.True(File.Exists(bundlePath));
-                Assert.True(File.Exists(Path.Combine(baseFolder, @"bin\test.wixpdb")));
+                Assert.IsTrue(File.Exists(bundlePath));
+                Assert.IsTrue(File.Exists(Path.Combine(baseFolder, @"bin\test.wixpdb")));
 
                 var extractResult = BundleExtractor.ExtractBAContainer(null, bundlePath, baFolderPath, extractFolderPath);
                 extractResult.AssertSuccess();
 
                 var bootstrapperExtensionDatas = extractResult.SelectBootstrapperExtensionDataNodes("/be:BootstrapperExtensionData/be:BootstrapperExtension[@Id='Wix4UtilBootstrapperExtension_X86']");
-                Assert.Equal(1, bootstrapperExtensionDatas.Count);
-                Assert.Equal("<BootstrapperExtension Id='Wix4UtilBootstrapperExtension_X86'>" +
+                Assert.AreEqual(1, bootstrapperExtensionDatas.Count);
+                Assert.AreEqual("<BootstrapperExtension Id='Wix4UtilBootstrapperExtension_X86'>" +
                     "<WixWindowsFeatureSearch Id='DetectSHA2SupportId' Type='sha2CodeSigning' />" +
                     "</BootstrapperExtension>", bootstrapperExtensionDatas[0].GetTestXml());
 
@@ -394,7 +395,7 @@ namespace WixToolsetTest.Util
             }
         }
 
-        [Fact]
+        [TestMethod]
         public void CanCreateUserGroupWithComment()
         {
             var folder = TestData.Get(@"TestData\CreateGroup");
@@ -550,7 +551,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CanCreateUserAccountWithComment()
         {
             var folder = TestData.Get(@"TestData\CreateUser");
@@ -626,7 +627,7 @@ namespace WixToolsetTest.Util
             }, results.OrderBy(s => s).ToArray());
         }
 
-        [Fact]
+        [TestMethod]
         public void CannotBuildBundleWithSearchesUsingBuiltinVariableNames()
         {
             var folder = TestData.Get("TestData", "BundleWithSearches");
diff --git a/src/ext/Util/test/WixToolsetTest.Util/WixToolsetTest.Util.csproj b/src/ext/Util/test/WixToolsetTest.Util/WixToolsetTest.Util.csproj
index 16d0e138..4036c3ab 100644
--- a/src/ext/Util/test/WixToolsetTest.Util/WixToolsetTest.Util.csproj
+++ b/src/ext/Util/test/WixToolsetTest.Util/WixToolsetTest.Util.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/Util/util.cmd b/src/ext/Util/util.cmd
deleted file mode 100644
index 3c66e7d8..00000000
--- a/src/ext/Util/util.cmd
+++ /dev/null
@@ -1,45 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-@set _L=%~dp0..\..\..\build\logs
-
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if /i "%1"=="inc" set _INC=1
-@if /i "%1"=="clean" set _CLEAN=1
-@if not "%1"=="" shift & goto parse_args
-
-@set _B=%~dp0..\..\..\build\Util.wixext\%_C%
-
-:: Clean
-
-@if "%_INC%"=="" call :clean
-@if NOT "%_CLEAN%"=="" goto :end
-
-@echo Building ext\Util %_C% using %_N%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror -bl:%_L%\ext_util_build.binlog || exit /b
-
-:: Test
-dotnet test ^
- %_B%\net6.0\WixToolsetTest.Util.dll ^
- --nologo -l "trx;LogFileName=%_L%\TestResults\util.wixext.trx" || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.Util.wixext.csproj || exit /b
-
-@goto :end
-
-:clean
-@rd /s/q "..\..\build\Util.wixext" 2> nul
-@del "..\..\build\artifacts\WixToolset.Util.wixext.*.nupkg" 2> nul
-@del "%_L%\ext_util_build.binlog" 2> nul
-@del "%_L%\TestResults\util.wixext.trx" 2> nul
-@rd /s/q "%USERPROFILE%\.nuget\packages\wixtoolset.util.wixext" 2> nul
-@exit /b
-
-:end
-@popd
-@endlocal
diff --git a/src/ext/Util/util_t.proj b/src/ext/Util/util_t.proj
new file mode 100644
index 00000000..e1da6adf
--- /dev/null
+++ b/src/ext/Util/util_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.Util\WixToolsetTest.Util.csproj" />
+    <ProjectReference Include="wixext\WixToolset.Util.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)Util.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.util.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.util.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.Util.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/VisualStudioExtensionFixture.cs b/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/VisualStudioExtensionFixture.cs
index f3e81e2d..992ac953 100644
--- a/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/VisualStudioExtensionFixture.cs
+++ b/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/VisualStudioExtensionFixture.cs
@@ -2,15 +2,16 @@
 
 namespace WixToolsetTest.VisualStudio
 {
-    using WixInternal.TestSupport;
-    using WixInternal.Core.TestPackage;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using WixInternal.MSTestSupport;
+    using WixInternal.Core.MSTestPackage;
     using WixToolset.VisualStudio;
-    using Xunit;
     using System.Linq;
 
+    [TestClass]
     public class VisualStudioExtensionFixture
     {
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingVsixPackage()
         {
             var folder = TestData.Get(@"TestData\UsingVsixPackage");
@@ -36,7 +37,7 @@ namespace WixToolsetTest.VisualStudio
             }, results);
         }
 
-        [Fact]
+        [TestMethod]
         public void CanBuildUsingVsixPackageOnArm64()
         {
             var folder = TestData.Get(@"TestData\UsingVsixPackage");
diff --git a/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/WixToolsetTest.VisualStudio.csproj b/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/WixToolsetTest.VisualStudio.csproj
index 2b0a7c1c..9cfb6867 100644
--- a/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/WixToolsetTest.VisualStudio.csproj
+++ b/src/ext/VisualStudio/test/WixToolsetTest.VisualStudio/WixToolsetTest.VisualStudio.csproj
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
 
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="MSTest.Sdk">
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
-    <IsWixTestProject>true</IsWixTestProject>
+    <IsWixMSTestProject>true</IsWixMSTestProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -16,6 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixInternal.Core.TestPackage" />
+    <PackageReference Include="WixInternal.MSTestSupport" />
+    <PackageReference Include="WixInternal.Core.MSTestPackage" />
   </ItemGroup>
 </Project>
diff --git a/src/ext/VisualStudio/visualstudio_t.proj b/src/ext/VisualStudio/visualstudio_t.proj
new file mode 100644
index 00000000..52de8019
--- /dev/null
+++ b/src/ext/VisualStudio/visualstudio_t.proj
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <ProjectReference Include="test\WixToolsetTest.VisualStudio\WixToolsetTest.VisualStudio.csproj" />
+    <ProjectReference Include="wixext\WixToolset.VisualStudio.wixext.csproj" Targets="Pack" Properties="NoBuild=true" />
+  </ItemGroup>
+
+  <Target Name="WixClean" BeforeTargets="Restore" Condition="'$(SuppressWixClean)' != 'true'">
+    <RemoveDir Directories="$(RootBuildFolder)VisualStudio.wixext" />
+    <RemoveDir Directories="$(USERPROFILE)\.nuget\packages\wixtoolset.VisualStudio.wixext" Condition="'$(NUGET_PACKAGES)' == ''" />
+    <RemoveDir Directories="$(NUGET_PACKAGES)\wixtoolset.VisualStudio.wixext" Condition="'$(NUGET_PACKAGES)' != ''" />
+
+    <Delete Files="$(ArtifactsFolder)WixToolset.VisualStudio.wixext.*.nupkg" />
+  </Target>
+</Project>
diff --git a/src/ext/VisualStudio/vs.cmd b/src/ext/VisualStudio/vs.cmd
deleted file mode 100644
index f0873f1d..00000000
--- a/src/ext/VisualStudio/vs.cmd
+++ /dev/null
@@ -1,21 +0,0 @@
-@setlocal
-@pushd %~dp0
-
-@set _C=Debug
-:parse_args
-@if /i "%1"=="release" set _C=Release
-@if not "%1"=="" shift & goto parse_args
-
-@echo VisualStudio.wixext build %_C%
-
-:: Build
-msbuild -Restore -p:Configuration=%_C% -tl -nologo -warnaserror || exit /b
-
-:: Test
-dotnet test -c %_C% --no-build test\WixToolsetTest.VisualStudio || exit /b
-
-:: Pack
-msbuild -t:Pack -p:Configuration=%_C% -tl -nologo -warnaserror -p:NoBuild=true wixext\WixToolset.VisualStudio.wixext.csproj || exit /b
-
-@popd
-@endlocal
diff --git a/src/ext/ext.cmd b/src/ext/ext.cmd
index 8575b81e..86aac47b 100644
--- a/src/ext/ext.cmd
+++ b/src/ext/ext.cmd
@@ -2,58 +2,15 @@
 @pushd %~dp0
 
 @set _C=Debug
+@set _L=%~dp0..\..\build\logs
+@set _SuppressWixClean=false
+
 :parse_args
 @if /i "%1"=="release" set _C=Release
+@if /i "%1"=="inc" set _SuppressWixClean=true
 @if not "%1"=="" shift & goto parse_args
 
-@echo ext build %_C%
-
-:: These extensions must be built in this order.
-
-:: Util
-call Util\util.cmd %_C% || exit /b
-
-:: Bal
-call Bal\bal.cmd %_C% || exit /b
-
-:: NetFx
-call NetFx\netfx.cmd %_C% || exit /b
-
-
-:: The rest of the extensions are in alphabetical order.
-
-:: ComPlus
-call ComPlus\complus.cmd %_C% || exit /b
-
-:: Dependency
-call Dependency\dependency.cmd %_C% || exit /b
-
-:: DirectX
-call DirectX\directx.cmd %_C% || exit /b
-
-:: Firewall
-call Firewall\firewall.cmd %_C% || exit /b
-
-:: Http
-call Http\http.cmd %_C% || exit /b
-
-:: Iis
-call Iis\iis.cmd %_C% || exit /b
-
-:: Msmq
-call Msmq\msmq.cmd %_C% || exit /b
-
-:: PowerShell
-call PowerShell\ps.cmd %_C% || exit /b
-
-:: Sql
-call Sql\sql.cmd %_C% || exit /b
-
-:: UI
-call UI\ui.cmd %_C% || exit /b
-
-:: VisualStudio
-call VisualStudio\vs.cmd %_C% || exit /b
+msbuild ext_t.proj -p:Configuration=%_C% -p:SuppressWixClean=%_SuppressWixClean% -m -tl -nologo -warnaserror -bl:%_L%\ext_build.binlog || exit /b
 
 @popd
 @endlocal
diff --git a/src/ext/ext_t.proj b/src/ext/ext_t.proj
new file mode 100644
index 00000000..e3301172
--- /dev/null
+++ b/src/ext/ext_t.proj
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.Build.Traversal">
+  <ItemGroup>
+    <!-- These projects are "special." -->
+    <ProjectReference Include="Util\util_t.proj" BuildInParallel="false" Targets="Restore;Build" Properties="SuppressWixTests=true" />
+    <ProjectReference Include="Bal\bal_t.proj" BuildInParallel="false" Targets="Restore;Build" Properties="SuppressWixTests=true" />
+    <!-- <ProjectReference Include="NetFx\netfx_t.proj" BuildInParallel="false" Targets="Restore;Build" Properties="SuppressWixTests=true" /> -->
+
+    <!-- Now run tests we skipped earlier along with everything in parallel. -->
+    <ProjectReference Include="Util\util_t.proj" Targets="Build" />
+    <ProjectReference Include="Bal\bal_t.proj" Targets="Build" />
+    <!-- <ProjectReference Include="NetFx\netfx_t.proj" Targets="Build" /> -->
+
+    <ProjectReference Include="NetFx\netfx_t.proj" BuildInParallel="false" Targets="Restore;Build" />
+    <ProjectReference Include="ComPlus\complus_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="Dependency\dependency_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="DirectX\directx_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="Firewall\firewall_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="Http\http_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="Iis\iis_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="Msmq\msmq_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="NetFx\netfx_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="PowerShell\powershell_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="Sql\sql_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="UI\ui_t.proj" Targets="Restore;Build" />
+    <ProjectReference Include="VisualStudio\visualstudio_t.proj" Targets="Restore;Build" />
+  </ItemGroup>
+</Project>
diff --git a/src/internal/SetBuildNumber/Directory.Packages.props.pp b/src/internal/SetBuildNumber/Directory.Packages.props.pp
index 8cf271d7..18a9b5eb 100644
--- a/src/internal/SetBuildNumber/Directory.Packages.props.pp
+++ b/src/internal/SetBuildNumber/Directory.Packages.props.pp
@@ -17,6 +17,7 @@
     <PackageVersion Include="WixToolset.Dtf.WindowsInstaller.Package" Version="{packageversion}" />
 
     <PackageVersion Include="WixInternal.TestSupport" Version="{packageversion}" />
+    <PackageVersion Include="WixInternal.MSTestSupport" Version="{packageversion}" />
     <PackageVersion Include="WixInternal.TestSupport.Native" Version="{packageversion}" />
     <PackageVersion Include="WixInternal.BaseBuildTasks.Sources" Version="{packageversion}" />
 
@@ -37,6 +38,7 @@
     <PackageVersion Include="WixToolset.Core.Burn" Version="{packageversion}" />
     <PackageVersion Include="WixToolset.Core.WindowsInstaller" Version="{packageversion}" />
     <PackageVersion Include="WixInternal.Core.TestPackage" Version="{packageversion}" />
+    <PackageVersion Include="WixInternal.Core.MSTestPackage" Version="{packageversion}" />
 
     <PackageVersion Include="WixToolset.Heat" Version="{packageversion}" />
 
@@ -98,6 +100,10 @@
   </ItemGroup>
 
   <ItemGroup>
+    <PackageVersion Include="MSTest.TestFramework" Version="3.7.3" />
+  </ItemGroup>
+
+  <ItemGroup>
     <PackageVersion Include="Microsoft.NET.Tools.NETCoreCheck.x86" Version="6.0.0" />
     <PackageVersion Include="Microsoft.NET.Tools.NETCoreCheck.x64" Version="6.0.0" />
     <PackageVersion Include="Microsoft.NET.Tools.NETCoreCheck.arm64" Version="6.0.0" />
diff --git a/src/internal/SetBuildNumber/global.json.pp b/src/internal/SetBuildNumber/global.json.pp
index bad3c0bd..fe48e6cc 100644
--- a/src/internal/SetBuildNumber/global.json.pp
+++ b/src/internal/SetBuildNumber/global.json.pp
@@ -1,6 +1,7 @@
 {
   "msbuild-sdks": {
-    "Microsoft.Build.Traversal": "3.2.0",
+    "MSTest.Sdk": "3.8.0",
+    "Microsoft.Build.Traversal": "4.1.82",
     "Microsoft.Build.NoTargets": "3.5.6",
     "WixToolset.Sdk": "{packageversion}"
   },
diff --git a/src/internal/WixInternal.MSTestSupport/Builder.cs b/src/internal/WixInternal.MSTestSupport/Builder.cs
new file mode 100644
index 00000000..62f2891b
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/Builder.cs
@@ -0,0 +1,204 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+
+    public class Builder
+    {
+        public Builder(string sourceFolder, Type extensionType = null, string[] bindPaths = null, string outputFile = null)
+        {
+            this.SourceFolder = sourceFolder;
+            if (extensionType != null)
+            {
+                this.ExtensionTypes = new Type[] { extensionType };
+            }
+            else
+            {
+                this.ExtensionTypes = new Type[] { };
+            }
+            this.BindPaths = bindPaths;
+            this.OutputFile = outputFile ?? "test.msi";
+        }
+
+        public Builder(string sourceFolder, Type[] extensionTypes, string[] bindPaths = null, string outputFile = null)
+        {
+            this.SourceFolder = sourceFolder;
+            this.ExtensionTypes = extensionTypes;
+            this.BindPaths = bindPaths;
+            this.OutputFile = outputFile ?? "test.msi";
+        }
+
+        public string[] BindPaths { get; set; }
+
+        public Type[] ExtensionTypes { get; set; }
+
+        public string OutputFile { get; set; }
+
+        public string SourceFolder { get; }
+
+        public string[] BuildAndQuery(Action<string[]> buildFunc, params string[] tables)
+        {
+            return this.BuildAndQuery(buildFunc, validate: false, tables);
+        }
+
+        public string[] BuildAndQuery(Action<string[]> buildFunc, bool validate, params string[] tables)
+        {
+            var sourceFiles = Directory.GetFiles(this.SourceFolder, "*.wxs");
+            var wxlFiles = Directory.GetFiles(this.SourceFolder, "*.wxl");
+
+            using (var fs = new DisposableFileSystem())
+            {
+                var intermediateFolder = fs.GetFolder();
+                var outputPath = Path.Combine(intermediateFolder, "bin", this.OutputFile);
+
+                var args = new List<string>
+                {
+                    "build",
+                    "-o", outputPath,
+                    "-intermediateFolder", intermediateFolder,
+                };
+
+                foreach (var ext in this.ExtensionTypes)
+                {
+                    args.Add("-ext");
+                    args.Add(Path.GetFullPath(ext.Assembly.Location));
+                }
+
+                args.AddRange(sourceFiles);
+
+                foreach (var wxlFile in wxlFiles)
+                {
+                    args.Add("-loc");
+                    args.Add(wxlFile);
+                }
+
+                foreach (var bindPath in this.BindPaths)
+                {
+                    args.Add("-bindpath");
+                    args.Add(bindPath);
+                }
+
+                buildFunc(args.ToArray());
+
+                if (validate)
+                {
+                    args = new List<string>
+                    {
+                        "msi",
+                        "validate",
+                        "-intermediateFolder", intermediateFolder,
+                        outputPath,
+                    };
+
+                    buildFunc(args.ToArray());
+                }
+
+                return Query.QueryDatabase(outputPath, tables);
+            }
+        }
+
+        public void BuildAndDecompileAndBuild(Action<string[]> buildFunc, Action<string[]> decompileFunc, string decompilePath, bool validate = false)
+        {
+            var sourceFiles = Directory.GetFiles(this.SourceFolder, "*.wxs");
+            var wxlFiles = Directory.GetFiles(this.SourceFolder, "*.wxl");
+
+            using (var fs = new DisposableFileSystem())
+            {
+                var intermediateFolder = fs.GetFolder();
+                var outputFolder = Path.Combine(intermediateFolder, "bin");
+                var decompileExtractFolder = Path.Combine(intermediateFolder, "decompiled", "extract");
+                var decompileIntermediateFolder = Path.Combine(intermediateFolder, "decompiled", "obj");
+                var decompileBuildFolder = Path.Combine(intermediateFolder, "decompiled", "bin");
+                var outputPath = Path.Combine(outputFolder, this.OutputFile);
+                var decompileBuildPath = Path.Combine(decompileBuildFolder, this.OutputFile);
+
+                // First build.
+                var firstBuildArgs = new List<string>
+                {
+                    "build",
+                    "-o", outputPath,
+                    "-intermediateFolder", intermediateFolder,
+                };
+
+                foreach (var ext in this.ExtensionTypes)
+                {
+                    firstBuildArgs.Add("-ext");
+                    firstBuildArgs.Add(Path.GetFullPath(ext.Assembly.Location));
+                }
+
+                firstBuildArgs.AddRange(sourceFiles);
+
+                foreach (var wxlFile in wxlFiles)
+                {
+                    firstBuildArgs.Add("-loc");
+                    firstBuildArgs.Add(wxlFile);
+                }
+
+                foreach (var bindPath in this.BindPaths)
+                {
+                    firstBuildArgs.Add("-bindpath");
+                    firstBuildArgs.Add(bindPath);
+                }
+
+                buildFunc(firstBuildArgs.ToArray());
+
+                if (validate)
+                {
+                    firstBuildArgs = new List<string>
+                    {
+                        "msi",
+                        "validate",
+                        "-intermediateFolder", intermediateFolder,
+                        outputPath,
+                    };
+
+                    buildFunc(firstBuildArgs.ToArray());
+                }
+
+                // Decompile built output.
+                var decompileArgs = new List<string>
+                {
+                    "msi", "decompile",
+                    outputPath,
+                    "-intermediateFolder", decompileIntermediateFolder,
+                    "-x", decompileExtractFolder,
+                    "-o", decompilePath
+                };
+
+                foreach (var ext in this.ExtensionTypes)
+                {
+                    decompileArgs.Add("-ext");
+                    decompileArgs.Add(Path.GetFullPath(ext.Assembly.Location));
+                }
+
+                decompileFunc(decompileArgs.ToArray());
+
+                // Build decompiled output.
+                var secondBuildArgs = new List<string>
+                {
+                    "build",
+                    decompilePath,
+                    "-o", decompileBuildPath,
+                    "-intermediateFolder", decompileIntermediateFolder
+                };
+
+                foreach (var ext in this.ExtensionTypes)
+                {
+                    secondBuildArgs.Add("-ext");
+                    secondBuildArgs.Add(Path.GetFullPath(ext.Assembly.Location));
+                }
+
+                secondBuildArgs.Add("-bindpath");
+                secondBuildArgs.Add(outputFolder);
+
+                secondBuildArgs.Add("-bindpath");
+                secondBuildArgs.Add(decompileExtractFolder);
+
+                buildFunc(secondBuildArgs.ToArray());
+            }
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/DisposableFileSystem.cs b/src/internal/WixInternal.MSTestSupport/DisposableFileSystem.cs
new file mode 100644
index 00000000..5e4bb23f
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/DisposableFileSystem.cs
@@ -0,0 +1,94 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+
+    public class DisposableFileSystem : IDisposable
+    {
+        protected bool Disposed { get; private set; }
+
+        private List<string> CleanupPaths { get; } = new List<string>();
+
+        public bool Keep { get; }
+
+        public DisposableFileSystem(bool keep = false)
+        {
+            this.Keep = keep;
+        }
+
+        protected string GetFile(bool create = false)
+        {
+            var path = Path.GetTempFileName();
+
+            if (!create)
+            {
+                File.Delete(path);
+            }
+
+            this.CleanupPaths.Add(path);
+
+            return path;
+        }
+
+        public string GetFolder(bool create = false)
+        {
+            // Always return a path with a space in it.
+            var path = Path.Combine(Path.GetTempPath(), ".WIXTEST " + Path.GetRandomFileName());
+
+            if (create)
+            {
+                Directory.CreateDirectory(path);
+            }
+
+            this.CleanupPaths.Add(path);
+
+            return path;
+        }
+
+
+        #region // IDisposable
+
+        public void Dispose()
+        {
+            this.Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (this.Disposed)
+            {
+                return;
+            }
+
+            if (disposing && !this.Keep)
+            {
+                foreach (var path in this.CleanupPaths)
+                {
+                    try
+                    {
+                        if (File.Exists(path))
+                        {
+                            File.Delete(path);
+                        }
+                        else if (Directory.Exists(path))
+                        {
+                            Directory.Delete(path, true);
+                        }
+                    }
+                    catch
+                    {
+                        // Best effort delete, so ignore any failures.
+                    }
+                }
+            }
+
+            this.Disposed = true;
+        }
+
+        #endregion
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/DotnetRunner.cs b/src/internal/WixInternal.MSTestSupport/DotnetRunner.cs
new file mode 100644
index 00000000..8fa3a739
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/DotnetRunner.cs
@@ -0,0 +1,57 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+
+    public class DotnetRunner : ExternalExecutable
+    {
+        private static readonly object InitLock = new object();
+        private static bool Initialized;
+        private static DotnetRunner Instance;
+
+        public static ExternalExecutableResult Execute(string command, string[] arguments = null) =>
+            InitAndExecute(command, arguments);
+
+        private static ExternalExecutableResult InitAndExecute(string command, string[] arguments)
+        {
+            lock (InitLock)
+            {
+                if (!Initialized)
+                {
+                    Initialized = true;
+                    var dotnetPath = Environment.GetEnvironmentVariable("DOTNET_HOST_PATH");
+                    if (String.IsNullOrEmpty(dotnetPath) || !File.Exists(dotnetPath))
+                    {
+                        dotnetPath = "dotnet";
+                    }
+
+                    Instance = new DotnetRunner(dotnetPath);
+                }
+            }
+
+            return Instance.ExecuteCore(command, arguments);
+        }
+
+        private DotnetRunner(string exePath) : base(exePath) { }
+
+        private ExternalExecutableResult ExecuteCore(string command, string[] arguments)
+        {
+            var total = new List<string>
+            {
+                command,
+            };
+
+            if (arguments != null)
+            {
+                total.AddRange(arguments);
+            }
+
+            var args = CombineArguments(total);
+            var mergeErrorIntoOutput = true;
+            return this.Run(args, mergeErrorIntoOutput);
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/ExternalExecutable.cs b/src/internal/WixInternal.MSTestSupport/ExternalExecutable.cs
new file mode 100644
index 00000000..927240ec
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/ExternalExecutable.cs
@@ -0,0 +1,374 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Concurrent;
+    using System.Collections.Generic;
+    using System.ComponentModel;
+    using System.Diagnostics;
+    using System.IO;
+    using System.Runtime.InteropServices;
+    using System.Text;
+    using System.Threading.Tasks;
+    using Microsoft.Win32.SafeHandles;
+
+    public abstract class ExternalExecutable
+    {
+        private readonly string exePath;
+
+        protected ExternalExecutable(string exePath)
+        {
+            this.exePath = exePath;
+        }
+
+        protected ExternalExecutableResult Run(string args, bool mergeErrorIntoOutput = false, string workingDirectory = null)
+        {
+            // https://github.com/dotnet/runtime/issues/58492
+            // Process.Start doesn't currently support starting a process with a long path,
+            // but the way to support long paths doesn't support searching for the executable if it was a relative path.
+            // Avoid the managed way of doing this even if the target isn't a long path to help verify that the native way works.
+            if (!Path.IsPathRooted(this.exePath))
+            {
+                return this.RunManaged(args, mergeErrorIntoOutput, workingDirectory);
+            }
+
+            // https://web.archive.org/web/20150331190801/https://support.microsoft.com/en-us/kb/190351
+            var commandLine = $"\"{this.exePath}\" {args}";
+            var currentDirectory = workingDirectory ?? Path.GetDirectoryName(this.exePath);
+            if (String.IsNullOrEmpty(currentDirectory))
+            {
+                currentDirectory = null;
+            }
+            var processInfo = new PROCESS_INFORMATION();
+            var startInfo = new STARTUPINFOW
+            {
+                cb = Marshal.SizeOf(typeof(STARTUPINFOW)),
+                dwFlags = StartupInfoFlags.STARTF_FORCEOFFFEEDBACK | StartupInfoFlags.STARTF_USESTDHANDLES,
+                hStdInput = GetStdHandle(StdHandleType.STD_INPUT_HANDLE),
+            };
+            SafeFileHandle hStdOutputParent = null;
+            SafeFileHandle hStdErrorParent = null;
+
+            try
+            {
+                CreatePipeForProcess(out hStdOutputParent, out startInfo.hStdOutput);
+
+                if (!mergeErrorIntoOutput)
+                {
+                    CreatePipeForProcess(out hStdErrorParent, out startInfo.hStdError);
+                }
+                else
+                {
+                    if (!DuplicateHandle(GetCurrentProcess(), startInfo.hStdOutput, GetCurrentProcess(), out startInfo.hStdError, 0, true, DuplicateHandleOptions.DUPLICATE_SAME_ACCESS))
+                    {
+                        throw new Win32Exception();
+                    }
+                }
+
+                if (!CreateProcessW(this.exePath, commandLine, IntPtr.Zero, IntPtr.Zero, true, CreateProcessFlags.CREATE_NO_WINDOW, IntPtr.Zero,
+                                    currentDirectory, ref startInfo, ref processInfo))
+                {
+                    throw new Win32Exception();
+                }
+
+                startInfo.Dispose();
+
+                return GetResultFromNative(mergeErrorIntoOutput, hStdOutputParent, hStdErrorParent, processInfo.hProcess, this.exePath, args);
+            }
+            finally
+            {
+                hStdErrorParent?.Dispose();
+                hStdOutputParent?.Dispose();
+
+                startInfo.Dispose();
+                processInfo.Dispose();
+            }
+        }
+
+        private static ExternalExecutableResult GetResultFromNative(bool mergeErrorIntoOutput, SafeFileHandle hStdOutputParent, SafeFileHandle hStdErrorParent, IntPtr hProcess, string fileName, string args)
+        {
+            using (var outputStream = new StreamReader(new FileStream(hStdOutputParent, FileAccess.Read)))
+            using (var errorStream = mergeErrorIntoOutput ? null : new StreamReader(new FileStream(hStdErrorParent, FileAccess.Read)))
+            {
+                var outputTask = Task.Run(() => ReadProcessStreamLines(outputStream));
+                var errorTask = Task.Run(() => ReadProcessStreamLines(errorStream));
+
+                while (!outputTask.Wait(100) || !errorTask.Wait(100)) { Task.Yield(); }
+                var standardOutput = outputTask.Result;
+                var standardError = errorTask.Result;
+
+                if (WaitForSingleObject(hProcess, -1) != 0)
+                {
+                    throw new Win32Exception();
+                }
+
+                if (!GetExitCodeProcess(hProcess, out var exitCode))
+                {
+                    throw new Win32Exception();
+                }
+
+                return new ExternalExecutableResult
+                {
+                    ExitCode = exitCode,
+                    StandardError = standardError,
+                    StandardOutput = standardOutput,
+                    FileName = fileName,
+                    Arguments = args,
+                };
+            }
+        }
+
+        private static string[] ReadProcessStreamLines(StreamReader streamReader)
+        {
+            if (streamReader == null)
+            {
+                return null;
+            }
+
+            var lines = new List<string>();
+            while (true)
+            {
+                var line = streamReader.ReadLine();
+                if (line == null)
+                {
+                    break;
+                }
+
+                lines.Add(line);
+            }
+
+            return lines.ToArray();
+        }
+
+        protected ExternalExecutableResult RunManaged(string args, bool mergeErrorIntoOutput = false, string workingDirectory = null)
+        {
+            var startInfo = new ProcessStartInfo(this.exePath, args)
+            {
+                CreateNoWindow = true,
+                RedirectStandardError = true,
+                RedirectStandardOutput = true,
+                UseShellExecute = false,
+                WorkingDirectory = workingDirectory ?? Path.GetDirectoryName(this.exePath),
+            };
+
+            using (var process = Process.Start(startInfo))
+            {
+                // This implementation of merging the streams does not guarantee that lines are retrieved in the same order that they were written.
+                // If the process is simultaneously writing to both streams, this is impossible to do anyway.
+                var standardOutput = new ConcurrentQueue<string>();
+                var standardError = mergeErrorIntoOutput ? standardOutput : new ConcurrentQueue<string>();
+
+                process.ErrorDataReceived += (s, e) => { if (e.Data != null) { standardError.Enqueue(e.Data); } };
+                process.OutputDataReceived += (s, e) => { if (e.Data != null) { standardOutput.Enqueue(e.Data); } };
+
+                process.BeginErrorReadLine();
+                process.BeginOutputReadLine();
+
+                process.WaitForExit();
+
+                return new ExternalExecutableResult
+                {
+                    ExitCode = process.ExitCode,
+                    StandardError = mergeErrorIntoOutput ? null : standardError.ToArray(),
+                    StandardOutput = standardOutput.ToArray(),
+                    FileName = this.exePath,
+                    Arguments = args,
+                };
+            }
+        }
+
+        // This is internal because it assumes backslashes aren't used as escape characters and there aren't any double quotes.
+        internal static string CombineArguments(IEnumerable<string> arguments)
+        {
+            if (arguments == null)
+            {
+                return null;
+            }
+
+            var sb = new StringBuilder();
+
+            foreach (var arg in arguments)
+            {
+                if (sb.Length > 0)
+                {
+                    sb.Append(' ');
+                }
+
+                if (arg.IndexOf(' ') > -1 && !arg.EndsWith("\""))
+                {
+                    sb.Append("\"");
+                    sb.Append(arg);
+                    sb.Append("\"");
+                }
+                else
+                {
+                    sb.Append(arg);
+                }
+            }
+
+            return sb.ToString();
+        }
+
+        private static void CreatePipeForProcess(out SafeFileHandle hReadPipe, out IntPtr hWritePipe)
+        {
+            var securityAttributes = new SECURITY_ATTRIBUTES
+            {
+                nLength = Marshal.SizeOf(typeof(SECURITY_ATTRIBUTES)),
+                bInheritHandle = true,
+            };
+
+            if (!CreatePipe(out var hReadTemp, out hWritePipe, ref securityAttributes, 0))
+            {
+                throw new Win32Exception();
+            }
+
+            // Only the handle passed to the process should be inheritable, so have to duplicate the other handle to get an uninheritable one.
+            if (!DuplicateHandle(GetCurrentProcess(), hReadTemp, GetCurrentProcess(), out var hReadPipePtr, 0, false, DuplicateHandleOptions.DUPLICATE_CLOSE_SOURCE | DuplicateHandleOptions.DUPLICATE_SAME_ACCESS))
+            {
+                throw new Win32Exception();
+            }
+
+            hReadPipe = new SafeFileHandle(hReadPipePtr, true);
+        }
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        private extern static IntPtr GetStdHandle(StdHandleType nStdHandle);
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        private extern static bool CreatePipe(out IntPtr hReadPipe, out IntPtr hWritePipe, ref SECURITY_ATTRIBUTES lpPipeAttributes, int nSize);
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        private extern static bool CreateProcessW(
+            string lpApplicationName,
+            string lpCommandLine,
+            IntPtr lpProcessAttributes,
+            IntPtr lpThreadAttributes,
+            [MarshalAs(UnmanagedType.Bool)] bool bInheritHandles,
+            CreateProcessFlags dwCreationFlags,
+            IntPtr lpEnvironment,
+            string lpCurrentDirectory,
+            ref STARTUPINFOW lpStartupInfo,
+            ref PROCESS_INFORMATION lpProcessInformation);
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true)]
+        private extern static IntPtr GetCurrentProcess();
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        private extern static bool GetExitCodeProcess(IntPtr hHandle, out int lpExitCode);
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        private extern static int WaitForSingleObject(IntPtr hHandle, int dwMilliseconds);
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        private extern static bool CloseHandle(IntPtr hObject);
+
+        [DllImport("kernel32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        private extern static bool DuplicateHandle(IntPtr hSourceProcessHandle, IntPtr hSourceHandle, IntPtr hTargetProcessHandle, out IntPtr lpTargetHandle, int dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, DuplicateHandleOptions dwOptions);
+
+        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+        private struct SECURITY_ATTRIBUTES
+        {
+            public int nLength;
+            public IntPtr lpSecurityDescriptor;
+            [MarshalAs(UnmanagedType.Bool)]
+            public bool bInheritHandle;
+        }
+
+        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+        private struct STARTUPINFOW
+        {
+            public int cb;
+            public string lpReserved;
+            public string lpDesktop;
+            public string lpTitle;
+            public int dwX;
+            public int dwY;
+            public int dwXSize;
+            public int dwYSize;
+            public int dwXCountChars;
+            public int dwYCountChars;
+            public int dwFillAttribute;
+            public StartupInfoFlags dwFlags;
+            public short wShowWindow;
+            public short cbReserved2;
+            public IntPtr lpReserved2;
+            public IntPtr hStdInput;
+            public IntPtr hStdOutput;
+            public IntPtr hStdError;
+
+            public void Dispose()
+            {
+                // This makes assumptions based on how it's used above.
+                if (this.hStdError != IntPtr.Zero)
+                {
+                    CloseHandle(this.hStdError);
+                    this.hStdError = IntPtr.Zero;
+                }
+
+                if (this.hStdOutput != IntPtr.Zero)
+                {
+                    CloseHandle(this.hStdOutput);
+                    this.hStdOutput = IntPtr.Zero;
+                }
+            }
+        }
+
+        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+        private struct PROCESS_INFORMATION
+        {
+            public IntPtr hProcess;
+            public IntPtr hThread;
+            public int dwProcessId;
+            public int dwThreadId;
+
+            public void Dispose()
+            {
+                if (this.hProcess != IntPtr.Zero)
+                {
+                    CloseHandle(this.hProcess);
+                    this.hProcess = IntPtr.Zero;
+                }
+
+                if (this.hThread != IntPtr.Zero)
+                {
+                    CloseHandle(this.hThread);
+                    this.hThread = IntPtr.Zero;
+                }
+            }
+        }
+
+        private enum StdHandleType
+        {
+            STD_INPUT_HANDLE = -10,
+            STD_OUTPUT_HANDLE = -11,
+            STD_ERROR_HANDLE = -12,
+        }
+
+        [Flags]
+        private enum CreateProcessFlags
+        {
+            None = 0x0,
+            CREATE_NO_WINDOW = 0x08000000,
+        }
+
+        [Flags]
+        private enum StartupInfoFlags
+        {
+            None = 0x0,
+            STARTF_FORCEOFFFEEDBACK = 0x80,
+            STARTF_USESTDHANDLES = 0x100,
+        }
+
+        private enum DuplicateHandleOptions
+        {
+            DUPLICATE_CLOSE_SOURCE = 1,
+            DUPLICATE_SAME_ACCESS = 2,
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/ExternalExecutableResult.cs b/src/internal/WixInternal.MSTestSupport/ExternalExecutableResult.cs
new file mode 100644
index 00000000..57bf0d11
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/ExternalExecutableResult.cs
@@ -0,0 +1,19 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System.Diagnostics;
+
+    public class ExternalExecutableResult
+    {
+        public int ExitCode { get; set; }
+
+        public string[] StandardError { get; set; }
+
+        public string[] StandardOutput { get; set; }
+
+        public string FileName { get; set; }
+
+        public string Arguments { get; set; }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/FakeBuildEngine.cs b/src/internal/WixInternal.MSTestSupport/FakeBuildEngine.cs
new file mode 100644
index 00000000..951d1bc8
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/FakeBuildEngine.cs
@@ -0,0 +1,33 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System.Collections;
+    using System.Text;
+    using Microsoft.Build.Framework;
+
+    public class FakeBuildEngine : IBuildEngine
+    {
+        private readonly StringBuilder output = new StringBuilder();
+
+        public int ColumnNumberOfTaskNode => 0;
+
+        public bool ContinueOnError => false;
+
+        public int LineNumberOfTaskNode => 0;
+
+        public string ProjectFileOfTaskNode => "fake_wix.targets";
+
+        public string Output => this.output.ToString();
+
+        public bool BuildProjectFile(string projectFileName, string[] targetNames, IDictionary globalProperties, IDictionary targetOutputs) => throw new System.NotImplementedException();
+
+        public void LogCustomEvent(CustomBuildEventArgs e) => this.output.AppendLine(e.Message);
+
+        public void LogErrorEvent(BuildErrorEventArgs e) => this.output.AppendLine(e.Message);
+
+        public void LogMessageEvent(BuildMessageEventArgs e) => this.output.AppendLine(e.Message);
+
+        public void LogWarningEvent(BuildWarningEventArgs e) => this.output.AppendLine(e.Message);
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/MsbuildRunner.cs b/src/internal/WixInternal.MSTestSupport/MsbuildRunner.cs
new file mode 100644
index 00000000..69fc7292
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/MsbuildRunner.cs
@@ -0,0 +1,112 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+
+    public class MsbuildRunner : ExternalExecutable
+    {
+        private static readonly string VswhereFindArguments = "-property installationPath -version [17.0,18.0)";
+        private static readonly string MsbuildCurrentRelativePath = @"MSBuild\Current\Bin\MSBuild.exe";
+        private static readonly string MsbuildCurrentRelativePath64 = @"MSBuild\Current\Bin\amd64\MSBuild.exe";
+
+        private static readonly object InitLock = new object();
+
+        private static bool Initialized;
+        private static MsbuildRunner MsbuildCurrentRunner;
+        private static MsbuildRunner MsbuildCurrentRunner64;
+
+        public static MsbuildRunnerResult Execute(string projectPath, string[] arguments = null, bool x64 = false) =>
+            InitAndExecute(String.Empty, projectPath, arguments, x64);
+
+        public static MsbuildRunnerResult ExecuteWithMsbuildCurrent(string projectPath, string[] arguments = null, bool x64 = false) =>
+            InitAndExecute("Current", projectPath, arguments, x64);
+
+        private static MsbuildRunnerResult InitAndExecute(string msbuildVersion, string projectPath, string[] arguments, bool x64)
+        {
+            lock (InitLock)
+            {
+                if (!Initialized)
+                {
+                    Initialized = true;
+                    var vswhereResult = VswhereRunner.Execute(VswhereFindArguments, true);
+                    if (vswhereResult.ExitCode != 0)
+                    {
+                        throw new InvalidOperationException($"Failed to execute vswhere.exe, exit code: {vswhereResult.ExitCode}. Output:\r\n{String.Join("\r\n", vswhereResult.StandardOutput)}");
+                    }
+
+                    string msbuildCurrentPath = null;
+                    string msbuildCurrentPath64 = null;
+
+                    foreach (var installPath in vswhereResult.StandardOutput)
+                    {
+                        if (msbuildCurrentPath == null)
+                        {
+                            var path = Path.Combine(installPath, MsbuildCurrentRelativePath);
+                            if (File.Exists(path))
+                            {
+                                msbuildCurrentPath = path;
+                            }
+                        }
+
+                        if (msbuildCurrentPath64 == null)
+                        {
+                            var path = Path.Combine(installPath, MsbuildCurrentRelativePath64);
+                            if (File.Exists(path))
+                            {
+                                msbuildCurrentPath64 = path;
+                            }
+                        }
+                    }
+
+                    if (msbuildCurrentPath != null)
+                    {
+                        MsbuildCurrentRunner = new MsbuildRunner(msbuildCurrentPath);
+                    }
+
+                    if (msbuildCurrentPath64 != null)
+                    {
+                        MsbuildCurrentRunner64 = new MsbuildRunner(msbuildCurrentPath64);
+                    }
+                }
+            }
+
+            MsbuildRunner runner = x64 ? MsbuildCurrentRunner64 : MsbuildCurrentRunner;
+
+            if (runner == null)
+            {
+                throw new InvalidOperationException($"Failed to find an installed{(x64 ? " 64-bit" : String.Empty)} MSBuild{msbuildVersion}");
+            }
+
+            return runner.ExecuteCore(projectPath, arguments);
+        }
+
+        private MsbuildRunner(string exePath) : base(exePath) { }
+
+        private MsbuildRunnerResult ExecuteCore(string projectPath, string[] arguments)
+        {
+            var total = new List<string>
+            {
+                projectPath,
+            };
+
+            if (arguments != null)
+            {
+                total.AddRange(arguments);
+            }
+
+            var args = CombineArguments(total);
+            var mergeErrorIntoOutput = true;
+            var workingFolder = Path.GetDirectoryName(projectPath);
+            var result = this.Run(args, mergeErrorIntoOutput, workingFolder);
+
+            return new MsbuildRunnerResult
+            {
+                ExitCode = result.ExitCode,
+                Output = result.StandardOutput,
+            };
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/MsbuildRunnerResult.cs b/src/internal/WixInternal.MSTestSupport/MsbuildRunnerResult.cs
new file mode 100644
index 00000000..02e25ebb
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/MsbuildRunnerResult.cs
@@ -0,0 +1,19 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+    public class MsbuildRunnerResult
+    {
+        public int ExitCode { get; set; }
+
+        public string[] Output { get; set; }
+
+        public void AssertSuccess()
+        {
+            Assert.IsTrue(0 == this.ExitCode, $"MSBuild failed unexpectedly. Output:{Environment.NewLine}{String.Join(Environment.NewLine, this.Output)}");
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/MsbuildUtilities.cs b/src/internal/WixInternal.MSTestSupport/MsbuildUtilities.cs
new file mode 100644
index 00000000..4776e6f1
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/MsbuildUtilities.cs
@@ -0,0 +1,99 @@
+// Copyright(c) .NET Foundation and contributors.All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+    using System.Linq;
+
+    public enum BuildSystem
+    {
+        DotNetCoreSdk,
+        MSBuild,
+        MSBuild64,
+    }
+
+    public static class MsbuildUtilities
+    {
+        public static MsbuildRunnerResult BuildProject(BuildSystem buildSystem, string projectPath, string[] arguments = null, string configuration = "Release", string verbosityLevel = "normal", bool suppressValidation = true)
+        {
+            var allArgs = new List<string>
+            {
+                $"-verbosity:{verbosityLevel}",
+                $"-p:Configuration={configuration}",
+                $"-p:SuppressValidation={suppressValidation}",
+                // Node reuse means that child msbuild processes can stay around after the build completes.
+                // Under that scenario, the root msbuild does not reliably close its streams which causes us to hang.
+                "-nr:false",
+                MsbuildUtilities.GetQuotedSwitch(buildSystem, "bl", Path.ChangeExtension(projectPath, ".binlog"))
+            };
+
+            if (arguments != null)
+            {
+                allArgs.AddRange(arguments);
+            }
+
+            switch (buildSystem)
+            {
+                case BuildSystem.DotNetCoreSdk:
+                    {
+                        allArgs.Add(projectPath);
+                        var result = DotnetRunner.Execute("msbuild", allArgs.ToArray());
+                        return new MsbuildRunnerResult
+                        {
+                            ExitCode = result.ExitCode,
+                            Output = result.StandardOutput,
+                        };
+                    }
+                case BuildSystem.MSBuild:
+                case BuildSystem.MSBuild64:
+                    {
+                        return MsbuildRunner.Execute(projectPath, allArgs.ToArray(), buildSystem == BuildSystem.MSBuild64);
+                    }
+                default:
+                    {
+                        throw new NotImplementedException();
+                    }
+            }
+        }
+
+        public static string GetQuotedSwitch(BuildSystem _, string switchName, string switchValue)
+        {
+            // If the value ends with a backslash, escape it.
+            if (switchValue?.EndsWith("\\") == true)
+            {
+                switchValue += @"\";
+            }
+
+            return $"-{switchName}:\"{switchValue}\"";
+        }
+
+        public static string GetQuotedPropertySwitch(BuildSystem buildSystem, string propertyName, string propertyValue)
+        {
+            // If the value ends with a backslash, escape it.
+            if (propertyValue?.EndsWith("\\") == true)
+            {
+                propertyValue += @"\";
+            }
+
+            var quotedValue = "\"" + propertyValue + "\"";
+
+            // If the value contains a semicolon then escape-quote it (wrap with the characters: \") to wrap the value
+            // instead of just quoting the value, otherwise dotnet.exe will not pass the value to MSBuild correctly.
+            if (buildSystem == BuildSystem.DotNetCoreSdk && propertyValue?.IndexOf(';') > -1)
+            {
+                quotedValue = "\\\"" + propertyValue + "\\\"";
+            }
+
+            return $"-p:{propertyName}={quotedValue}";
+        }
+
+        public static IEnumerable<string> GetToolCommandLines(MsbuildRunnerResult result, string toolName, string operation, BuildSystem buildSystem)
+        {
+            var expectedToolExe = buildSystem == BuildSystem.DotNetCoreSdk ? $"{toolName}.dll\"" : $"{toolName}.exe";
+            var expectedToolCommand = $"{expectedToolExe} {operation}";
+            return result.Output.Where(line => line.Contains(expectedToolCommand));
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/Pushd.cs b/src/internal/WixInternal.MSTestSupport/Pushd.cs
new file mode 100644
index 00000000..7086ffd0
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/Pushd.cs
@@ -0,0 +1,46 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.IO;
+
+    public class Pushd : IDisposable
+    {
+        protected bool Disposed { get; private set; }
+
+        public Pushd(string path)
+        {
+            this.PreviousDirectory = Directory.GetCurrentDirectory();
+
+            Directory.SetCurrentDirectory(path);
+        }
+
+        public string PreviousDirectory { get; }
+
+        #region // IDisposable
+
+        public void Dispose()
+        {
+            this.Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (this.Disposed)
+            {
+                return;
+            }
+
+            if (disposing)
+            {
+                Directory.SetCurrentDirectory(this.PreviousDirectory);
+            }
+
+            this.Disposed = true;
+        }
+
+        #endregion
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/Query.cs b/src/internal/WixInternal.MSTestSupport/Query.cs
new file mode 100644
index 00000000..5a8868b3
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/Query.cs
@@ -0,0 +1,207 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+    using System.Linq;
+    using System.Text;
+    using WixToolset.Dtf.Compression.Cab;
+    using WixToolset.Dtf.WindowsInstaller;
+
+    public class Query
+    {
+        public static string[] QueryDatabase(string path, string[] tables)
+        {
+            var results = new List<string>();
+            var resultsByTable = QueryDatabaseByTable(path, tables);
+            var sortedTables = tables.ToList();
+            sortedTables.Sort();
+            foreach (var tableName in sortedTables)
+            {
+                var rows = resultsByTable[tableName];
+                rows?.ForEach(r => results.Add($"{tableName}:{r}"));
+            }
+            return results.ToArray();
+        }
+
+        public static string[] QueryDatabase(Database db, string[] tables)
+        {
+            var results = new List<string>();
+            var resultsByTable = QueryDatabaseByTable(db, tables);
+            var sortedTables = tables.ToList();
+            sortedTables.Sort();
+            foreach (var tableName in sortedTables)
+            {
+                var rows = resultsByTable[tableName];
+                rows?.ForEach(r => results.Add($"{tableName}:{r}"));
+            }
+            return results.ToArray();
+        }
+
+        /// <summary>
+        /// Returns rows from requested tables formatted to facilitate testing.
+        /// If the table did not exist in the database, its list will be null.
+        /// </summary>
+        /// <param name="path"></param>
+        /// <param name="tables"></param>
+        /// <returns></returns>
+        public static Dictionary<string, List<string>> QueryDatabaseByTable(string path, string[] tables)
+        {
+            var results = new Dictionary<string, List<string>>();
+
+            if (tables?.Length > 0)
+            {
+                using (var db = new Database(path))
+                {
+                    results = QueryDatabaseByTable(db, tables);
+                }
+            }
+
+            return results;
+        }
+
+        /// <summary>
+        /// Returns rows from requested tables formatted to facilitate testing.
+        /// If the table did not exist in the database, its list will be null.
+        /// </summary>
+        /// <param name="db"></param>
+        /// <param name="tables"></param>
+        /// <returns></returns>
+        public static Dictionary<string, List<string>> QueryDatabaseByTable(Database db, string[] tables)
+        {
+            var results = new Dictionary<string, List<string>>();
+
+            if (tables?.Length > 0)
+            {
+                var sb = new StringBuilder();
+
+                foreach (var table in tables)
+                {
+                    if (table == "_SummaryInformation")
+                    {
+                        var entries = new List<string>();
+                        results.Add(table, entries);
+
+                        entries.Add($"Title\t{db.SummaryInfo.Title}");
+                        entries.Add($"Subject\t{db.SummaryInfo.Subject}");
+                        entries.Add($"Author\t{db.SummaryInfo.Author}");
+                        entries.Add($"Keywords\t{db.SummaryInfo.Keywords}");
+                        entries.Add($"Comments\t{db.SummaryInfo.Comments}");
+                        entries.Add($"Template\t{db.SummaryInfo.Template}");
+                        entries.Add($"CodePage\t{db.SummaryInfo.CodePage}");
+                        entries.Add($"PageCount\t{db.SummaryInfo.PageCount}");
+                        entries.Add($"WordCount\t{db.SummaryInfo.WordCount}");
+                        entries.Add($"CharacterCount\t{db.SummaryInfo.CharacterCount}");
+                        entries.Add($"Security\t{db.SummaryInfo.Security}");
+
+                        continue;
+                    }
+
+                    if (!db.IsTablePersistent(table))
+                    {
+                        results.Add(table, null);
+                        continue;
+                    }
+
+                    var rows = new List<string>();
+                    results.Add(table, rows);
+
+                    using (var view = db.OpenView("SELECT * FROM `{0}`", table))
+                    {
+                        view.Execute();
+
+                        Record record;
+                        while ((record = view.Fetch()) != null)
+                        {
+                            sb.Clear();
+
+                            using (record)
+                            {
+                                for (var i = 0; i < record.FieldCount; ++i)
+                                {
+                                    if (i > 0)
+                                    {
+                                        sb.Append("\t");
+                                    }
+
+                                    sb.Append(record[i + 1]?.ToString());
+                                }
+                            }
+
+                            rows.Add(sb.ToString());
+                        }
+                    }
+
+                    rows.Sort();
+               }
+            }
+
+            return results;
+        }
+
+        public static CabFileInfo[] GetCabinetFiles(string path)
+        {
+            var cab = new CabInfo(path);
+
+            var result = cab.GetFiles();
+
+            return result.Select(c => c).ToArray();
+        }
+
+        public static void ExtractStream(string path, string streamName, string outputPath)
+        {
+            Directory.CreateDirectory(Path.GetDirectoryName(outputPath));
+
+            using (var db = new Database(path))
+            using (var view = db.OpenView("SELECT `Data` FROM `_Streams` WHERE `Name` = '{0}'", streamName))
+            {
+                view.Execute();
+
+                using (var record = view.Fetch())
+                {
+                    record.GetStream(1, outputPath);
+                }
+            }
+        }
+
+        public static void ExtractSubStorage(string path, string subStorageName, string outputPath)
+        {
+            Directory.CreateDirectory(Path.GetDirectoryName(outputPath));
+
+            using (var db = new Database(path))
+            using (var view = db.OpenView("SELECT `Name`, `Data` FROM `_Storages` WHERE `Name` = '{0}'", subStorageName))
+            {
+                view.Execute();
+
+                using (var record = view.Fetch())
+                {
+                    var name = record.GetString(1);
+                    record.GetStream(2, outputPath);
+                }
+            }
+        }
+
+        public static string[] GetSubStorageNames(string path)
+        {
+            var result = new List<string>();
+
+            using (var db = new Database(path))
+            using (var view = db.OpenView("SELECT `Name` FROM `_Storages`"))
+            {
+                view.Execute();
+
+                Record record;
+                while ((record = view.Fetch()) != null)
+                {
+                    var name = record.GetString(1);
+                    result.Add(name);
+                }
+            }
+
+            result.Sort();
+            return result.ToArray();
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/RobocopyRunner.cs b/src/internal/WixInternal.MSTestSupport/RobocopyRunner.cs
new file mode 100644
index 00000000..7ad8f6fe
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/RobocopyRunner.cs
@@ -0,0 +1,16 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    public class RobocopyRunner : ExternalExecutable
+    {
+        private static readonly RobocopyRunner Instance = new RobocopyRunner();
+
+        private RobocopyRunner() : base("robocopy") { }
+
+        public static ExternalExecutableResult Execute(string args)
+        {
+            return Instance.Run(args);
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/TestData.cs b/src/internal/WixInternal.MSTestSupport/TestData.cs
new file mode 100644
index 00000000..5f167a87
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/TestData.cs
@@ -0,0 +1,78 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.IO;
+    using System.Reflection;
+    using System.Runtime.CompilerServices;
+
+    public class TestData
+    {
+        public static void CreateFile(string path, long size, bool fill = false)
+        {
+            // Ensure the directory exists.
+            path = Path.GetFullPath(path);
+            Directory.CreateDirectory(Path.GetDirectoryName(path));
+
+            using (var file = File.OpenWrite(path))
+            {
+                if (fill)
+                {
+                    var random = new Random();
+                    var bytes = new byte[4096];
+                    var generated = 0L;
+
+                    // Put fill bytes in the file so it doesn't compress trivially.
+                    while (generated < size)
+                    {
+                        var generate = (int)Math.Min(size - generated, bytes.Length);
+
+                        random.NextBytes(bytes);
+
+                        file.Write(bytes, 0, generate);
+
+                        generated += generate;
+                    }
+                }
+                else
+                {
+                    file.SetLength(size);
+                }
+            }
+        }
+
+        public static string Get(params string[] paths)
+        {
+            var localPath = AppDomain.CurrentDomain.BaseDirectory;
+            return Path.Combine(localPath, Path.Combine(paths));
+        }
+
+        public static string GetUnitTestLogsFolder([CallerFilePath] string path = "", [CallerMemberName] string method = "")
+        {
+            var startingPath = AppDomain.CurrentDomain.BaseDirectory;
+            var buildPath = startingPath;
+
+            while (!String.IsNullOrEmpty(buildPath))
+            {
+                var folderName = Path.GetFileName(buildPath);
+                if (String.Equals("build", folderName, StringComparison.OrdinalIgnoreCase))
+                {
+                    break;
+                }
+
+                buildPath = Path.GetDirectoryName(buildPath);
+            }
+
+            if (String.IsNullOrEmpty(buildPath))
+            {
+                throw new InvalidOperationException($"Could not find the 'build' folder in the test path: {startingPath}. Cannot get test logs folder without being able to find the build folder.");
+            }
+
+            var testLogsFolder = Path.Combine(buildPath, "logs", "UnitTests", $"{Path.GetFileNameWithoutExtension(path)}_{method}");
+            Directory.CreateDirectory(testLogsFolder);
+
+            return testLogsFolder;
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/TestDataFolderFileSystem.cs b/src/internal/WixInternal.MSTestSupport/TestDataFolderFileSystem.cs
new file mode 100644
index 00000000..1fea9665
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/TestDataFolderFileSystem.cs
@@ -0,0 +1,42 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+
+    /// <summary>
+    /// This class builds on top of DisposableFileSystem
+    /// to make it easy to write a test that needs a whole folder of test data copied to a temp location
+    /// that will automatically be cleaned up at the end of the test.
+    /// </summary>
+    public class TestDataFolderFileSystem : IDisposable
+    {
+        private DisposableFileSystem fileSystem;
+
+        public string BaseFolder { get; private set; }
+
+        public void Dispose()
+        {
+            this.fileSystem?.Dispose();
+        }
+
+        public void Initialize(string sourceDirectoryPath)
+        {
+            if (this.fileSystem != null)
+            {
+                throw new InvalidOperationException();
+            }
+            this.fileSystem = new DisposableFileSystem();
+
+            this.BaseFolder = this.fileSystem.GetFolder();
+
+            RobocopyFolder(sourceDirectoryPath, this.BaseFolder);
+        }
+
+        public static ExternalExecutableResult RobocopyFolder(string sourceFolderPath, string destinationFolderPath)
+        {
+            var args = $"\"{sourceFolderPath}\" \"{destinationFolderPath}\" /E /R:1 /W:1";
+            return RobocopyRunner.Execute(args);
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/VswhereRunner.cs b/src/internal/WixInternal.MSTestSupport/VswhereRunner.cs
new file mode 100644
index 00000000..f6ff2116
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/VswhereRunner.cs
@@ -0,0 +1,41 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.IO;
+
+    public class VswhereRunner : ExternalExecutable
+    {
+        private static readonly string VswhereRelativePath = @"Microsoft Visual Studio\Installer\vswhere.exe";
+
+        private static readonly object InitLock = new object();
+        private static bool Initialized;
+        private static VswhereRunner Instance;
+
+        public static ExternalExecutableResult Execute(string args, bool mergeErrorIntoOutput = false) =>
+            InitAndExecute(args, mergeErrorIntoOutput);
+
+        private static ExternalExecutableResult InitAndExecute(string args, bool mergeErrorIntoOutput)
+        {
+            lock (InitLock)
+            {
+                if (!Initialized)
+                {
+                    Initialized = true;
+                    var vswherePath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86), VswhereRelativePath);
+                    if (!File.Exists(vswherePath))
+                    {
+                        throw new InvalidOperationException($"Failed to find vswhere at: {vswherePath}");
+                    }
+
+                    Instance = new VswhereRunner(vswherePath);
+                }
+            }
+
+            return Instance.Run(args, mergeErrorIntoOutput);
+        }
+
+        private VswhereRunner(string exePath) : base(exePath) { }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/WixAssert.cs b/src/internal/WixInternal.MSTestSupport/WixAssert.cs
new file mode 100644
index 00000000..927ebee6
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/WixAssert.cs
@@ -0,0 +1,164 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+    using System.Text;
+    using System.Xml.Linq;
+
+    public class WixAssert
+    {
+        public static void CompareLineByLine(string[] expectedLines, string[] actualLines)
+        {
+            var lineNumber = 0;
+
+            for (; lineNumber < expectedLines.Length && lineNumber < actualLines.Length; ++lineNumber)
+            {
+                StringEqual($"{lineNumber}: {expectedLines[lineNumber]}", $"{lineNumber}: {actualLines[lineNumber]}");
+            }
+
+            var additionalExpectedLines = expectedLines.Length > lineNumber ? String.Join(Environment.NewLine, expectedLines.Skip(lineNumber).Select((s, i) => $"{lineNumber + i}: {s}")) : $"Missing {actualLines.Length - lineNumber} lines";
+            var additionalActualLines = actualLines.Length > lineNumber ? String.Join(Environment.NewLine, actualLines.Skip(lineNumber).Select((s, i) => $"{lineNumber + i}: {s}")) : $"Missing {expectedLines.Length - lineNumber} lines";
+
+            Assert.AreEqual<object>(additionalExpectedLines, additionalActualLines, StringObjectEqualityComparer.InvariantCulture);
+        }
+
+        public static void CompareXml(XContainer xExpected, XContainer xActual)
+        {
+            var expecteds = ComparableElements(xExpected);
+            var actuals = ComparableElements(xActual);
+
+            CompareLineByLine(expecteds.OrderBy(s => s).ToArray(), actuals.OrderBy(s => s).ToArray());
+        }
+
+        public static void CompareXml(string expectedPath, string actualPath)
+        {
+            var expectedDoc = XDocument.Load(expectedPath, LoadOptions.PreserveWhitespace | LoadOptions.SetBaseUri | LoadOptions.SetLineInfo);
+            var actualDoc = XDocument.Load(actualPath, LoadOptions.PreserveWhitespace | LoadOptions.SetBaseUri | LoadOptions.SetLineInfo);
+
+            CompareXml(expectedDoc, actualDoc);
+        }
+
+        private static IEnumerable<string> ComparableElements(XContainer container)
+        {
+            return container.Descendants().Select(x => $"{x.Name.LocalName}:{String.Join(",", x.Attributes().OrderBy(a => a.Name.LocalName).Select(a => $"{a.Name.LocalName}={ComparableAttribute(a)}"))}");
+        }
+
+        private static string ComparableAttribute(XAttribute attribute)
+        {
+            switch (attribute.Name.LocalName)
+            {
+                case "SourceFile":
+                    return "<SourceFile>";
+                default:
+                    return attribute.Value;
+            }
+        }
+
+        public static void StringCollectionEmpty(IList<string> collection)
+        {
+            if (collection.Count > 0)
+            {
+                Assert.Fail($"The collection was expected to be empty, but instead was [{Environment.NewLine}\"{String.Join($"\", {Environment.NewLine}\"", collection)}\"{Environment.NewLine}]");
+            }
+        }
+
+        public static void StringEqual(string expected, string actual, bool ignoreCase = false)
+        {
+            WixStringEqualException.ThrowIfNotEqual(expected, actual, ignoreCase);
+        }
+
+        public static void NotStringEqual(string expected, string actual, bool ignoreCase = false)
+        {
+            var comparer = ignoreCase ? StringObjectEqualityComparer.InvariantCultureIgnoreCase : StringObjectEqualityComparer.InvariantCulture;
+            Assert.AreNotEqual(expected, actual, comparer);
+        }
+
+        public static void Single<T>(IEnumerable<T> collection)
+        {
+            Assert.AreEqual(1, collection.Count());
+        }
+
+        public static void Single<T>(IEnumerable<T> collection, Func<T, bool> predicate)
+        {
+            var results = collection.Where(predicate);
+            Assert.AreEqual(1, results.Count());
+        }
+
+        public static void Empty<T>(IEnumerable<T> collection)
+        {
+            Assert.AreEqual(0, collection.Count());
+        }
+
+        public static void Empty<T>(IEnumerable<T> collection, Func<T, bool> predicate)
+        {
+            var results = collection.Where(predicate);
+            Assert.AreEqual(0, results.Count());
+        }
+    }
+
+    internal class StringObjectEqualityComparer : IEqualityComparer<object>
+    {
+        public static readonly StringObjectEqualityComparer InvariantCultureIgnoreCase = new StringObjectEqualityComparer(true);
+        public static readonly StringObjectEqualityComparer InvariantCulture = new StringObjectEqualityComparer(false);
+
+        private readonly StringComparer stringComparer;
+
+        public StringObjectEqualityComparer(bool ignoreCase)
+        {
+            this.stringComparer = ignoreCase ? StringComparer.InvariantCultureIgnoreCase : StringComparer.InvariantCulture;
+        }
+
+        public new bool Equals(object x, object y)
+        {
+            return this.stringComparer.Equals((string)x, (string)y);
+        }
+
+        public int GetHashCode(object obj)
+        {
+            return this.stringComparer.GetHashCode((string)obj);
+        }
+    }
+
+    public class WixStringEqualException : AssertFailedException
+    {
+        public WixStringEqualException(string userMessage) : base(userMessage) { }
+
+        public static void ThrowIfNotEqual(string expected, string actual, bool ignoreCase)
+        {
+            var comparer = ignoreCase ? StringObjectEqualityComparer.InvariantCultureIgnoreCase : StringObjectEqualityComparer.InvariantCulture;
+            if (comparer.Equals(expected, actual))
+            {
+                return;
+            }
+
+            var sbMessage = new StringBuilder();
+
+            try
+            {
+                Assert.AreEqual(expected, actual, ignoreCase);
+            }
+            catch (AssertFailedException xe)
+            {
+                // If either string is not completely in the message, then make sure it gets in there.
+                if (!xe.Message.Contains(expected) || !xe.Message.Contains(actual))
+                {
+                    sbMessage.AppendLine(xe.Message);
+                    sbMessage.AppendLine();
+                    sbMessage.AppendFormat("Expected: {0}", expected);
+                    sbMessage.AppendLine();
+                    sbMessage.AppendFormat("Actual:   {0}", actual);
+                }
+                else
+                {
+                    throw;
+                }
+            }
+
+            throw new WixStringEqualException(sbMessage.ToString());
+        }
+    }
+}
diff --git a/src/internal/WixInternal.MSTestSupport/WixInternal.MSTestSupport.csproj b/src/internal/WixInternal.MSTestSupport/WixInternal.MSTestSupport.csproj
new file mode 100644
index 00000000..b48aacd4
--- /dev/null
+++ b/src/internal/WixInternal.MSTestSupport/WixInternal.MSTestSupport.csproj
@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>net6.0;net472</TargetFrameworks>
+    <IsPackable>true</IsPackable>
+    <DebugType>embedded</DebugType>
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <CreateDocumentationFile>true</CreateDocumentationFile>
+    <NoWarn>$(NoWarn);CS1591</NoWarn>
+    <SignOutput>false</SignOutput>
+    <IsWixTestSupportProject>true</IsWixTestSupportProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Build.Tasks.Core" />
+    <PackageReference Include="WixToolset.Dtf.WindowsInstaller" />
+    <PackageReference Include="WixToolset.Dtf.Compression" />
+    <PackageReference Include="WixToolset.Dtf.Compression.Cab" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="MSTest.TestFramework" />
+  </ItemGroup>
+</Project>
diff --git a/src/internal/WixInternal.TestSupport/WixAssert.cs b/src/internal/WixInternal.TestSupport/WixAssert.cs
new file mode 100644
index 00000000..40355131
--- /dev/null
+++ b/src/internal/WixInternal.TestSupport/WixAssert.cs
@@ -0,0 +1,143 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.MSTestSupport
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+    using System.Text;
+    using System.Xml.Linq;
+    using Xunit;
+    using Xunit.Sdk;
+
+    public class WixAssert
+    {
+        public static void CompareLineByLine(string[] expectedLines, string[] actualLines)
+        {
+            var lineNumber = 0;
+
+            for (; lineNumber < expectedLines.Length && lineNumber < actualLines.Length; ++lineNumber)
+            {
+                StringEqual($"{lineNumber}: {expectedLines[lineNumber]}", $"{lineNumber}: {actualLines[lineNumber]}");
+            }
+
+            var additionalExpectedLines = expectedLines.Length > lineNumber ? String.Join(Environment.NewLine, expectedLines.Skip(lineNumber).Select((s, i) => $"{lineNumber + i}: {s}")) : $"Missing {actualLines.Length - lineNumber} lines";
+            var additionalActualLines = actualLines.Length > lineNumber ? String.Join(Environment.NewLine, actualLines.Skip(lineNumber).Select((s, i) => $"{lineNumber + i}: {s}")) : $"Missing {expectedLines.Length - lineNumber} lines";
+
+            Assert.Equal<object>(additionalExpectedLines, additionalActualLines, StringObjectEqualityComparer.InvariantCulture);
+        }
+
+        public static void CompareXml(XContainer xExpected, XContainer xActual)
+        {
+            var expecteds = ComparableElements(xExpected);
+            var actuals = ComparableElements(xActual);
+
+            CompareLineByLine(expecteds.OrderBy(s => s).ToArray(), actuals.OrderBy(s => s).ToArray());
+        }
+
+        public static void CompareXml(string expectedPath, string actualPath)
+        {
+            var expectedDoc = XDocument.Load(expectedPath, LoadOptions.PreserveWhitespace | LoadOptions.SetBaseUri | LoadOptions.SetLineInfo);
+            var actualDoc = XDocument.Load(actualPath, LoadOptions.PreserveWhitespace | LoadOptions.SetBaseUri | LoadOptions.SetLineInfo);
+
+            CompareXml(expectedDoc, actualDoc);
+        }
+
+        private static IEnumerable<string> ComparableElements(XContainer container)
+        {
+            return container.Descendants().Select(x => $"{x.Name.LocalName}:{String.Join(",", x.Attributes().OrderBy(a => a.Name.LocalName).Select(a => $"{a.Name.LocalName}={ComparableAttribute(a)}"))}");
+        }
+
+        private static string ComparableAttribute(XAttribute attribute)
+        {
+            switch (attribute.Name.LocalName)
+            {
+                case "SourceFile":
+                    return "<SourceFile>";
+                default:
+                    return attribute.Value;
+            }
+        }
+
+        public static void StringCollectionEmpty(IList<string> collection)
+        {
+            if (collection.Count > 0)
+            {
+                Assert.Fail($"The collection was expected to be empty, but instead was [{Environment.NewLine}\"{String.Join($"\", {Environment.NewLine}\"", collection)}\"{Environment.NewLine}]");
+            }
+        }
+
+        public static void StringEqual(string expected, string actual, bool ignoreCase = false)
+        {
+            WixStringEqualException.ThrowIfNotEqual(expected, actual, ignoreCase);
+        }
+
+        public static void NotStringEqual(string expected, string actual, bool ignoreCase = false)
+        {
+            var comparer = ignoreCase ? StringObjectEqualityComparer.InvariantCultureIgnoreCase : StringObjectEqualityComparer.InvariantCulture;
+            Assert.NotEqual(expected, actual, comparer);
+        }
+    }
+
+    internal class StringObjectEqualityComparer : IEqualityComparer<object>
+    {
+        public static readonly StringObjectEqualityComparer InvariantCultureIgnoreCase = new StringObjectEqualityComparer(true);
+        public static readonly StringObjectEqualityComparer InvariantCulture = new StringObjectEqualityComparer(false);
+
+        private readonly StringComparer stringComparer;
+
+        public StringObjectEqualityComparer(bool ignoreCase)
+        {
+            this.stringComparer = ignoreCase ? StringComparer.InvariantCultureIgnoreCase : StringComparer.InvariantCulture;
+        }
+
+        public new bool Equals(object x, object y)
+        {
+            return this.stringComparer.Equals((string)x, (string)y);
+        }
+
+        public int GetHashCode(object obj)
+        {
+            return this.stringComparer.GetHashCode((string)obj);
+        }
+    }
+
+    public class WixStringEqualException : XunitException
+    {
+        public WixStringEqualException(string userMessage) : base(userMessage) { }
+
+        public static void ThrowIfNotEqual(string expected, string actual, bool ignoreCase)
+        {
+            var comparer = ignoreCase ? StringObjectEqualityComparer.InvariantCultureIgnoreCase : StringObjectEqualityComparer.InvariantCulture;
+            if (comparer.Equals(expected, actual))
+            {
+                return;
+            }
+
+            var sbMessage = new StringBuilder();
+
+            try
+            {
+                Assert.Equal(expected, actual, ignoreCase);
+            }
+            catch (XunitException xe)
+            {
+                // If either string is not completely in the message, then make sure it gets in there.
+                if (!xe.Message.Contains(expected) || !xe.Message.Contains(actual))
+                {
+                    sbMessage.AppendLine(xe.Message);
+                    sbMessage.AppendLine();
+                    sbMessage.AppendFormat("Expected: {0}", expected);
+                    sbMessage.AppendLine();
+                    sbMessage.AppendFormat("Actual:   {0}", actual);
+                }
+                else
+                {
+                    throw;
+                }
+            }
+
+            throw new WixStringEqualException(sbMessage.ToString());
+        }
+    }
+}
diff --git a/src/internal/WixInternal.TestSupport/XunitExtensions/WixAssert.cs b/src/internal/WixInternal.TestSupport/XunitExtensions/WixAssert.cs
index 5ac28de1..131d4e83 100644
--- a/src/internal/WixInternal.TestSupport/XunitExtensions/WixAssert.cs
+++ b/src/internal/WixInternal.TestSupport/XunitExtensions/WixAssert.cs
@@ -105,6 +105,32 @@ namespace WixInternal.TestSupport
             Assert.NotEqual<object>(expected, actual, comparer);
         }
 
+        public static void Single(IEnumerable<string> collection)
+        {
+            Assert.Single(collection);
+            // TODO: MSTEST: Assert.Equal(1, collection.Count());
+        }
+
+        public static void Single(IEnumerable<string> collection, Func<string, bool> predicate)
+        {
+            var results = collection.Where(predicate);
+            Assert.Single(results);
+            // TODO: MSTEST: Assert.Equal(1, results.Count());
+        }
+
+        public static void Empty(IEnumerable<string> collection)
+        {
+            Assert.Empty(collection);
+            // TODO: MSTEST: Assert.Equal(0, collection.Count());
+        }
+
+        public static void Empty(IEnumerable<string> collection, Func<string, bool> predicate)
+        {
+            var results = collection.Where(predicate);
+            Assert.Empty(results);
+            // TODO: MSTEST: Assert.Equal(0, results.Count());
+        }
+
         // There appears to have been a bug in VC++, which might or might not have been partially
         // or completely corrected. It was unable to disambiguate a call to:
         //     Xunit::Assert::Throws(System::Type^, System::Action^)
diff --git a/src/internal/internal.sln b/src/internal/internal.sln
index e8d8db17..5514e543 100644
--- a/src/internal/internal.sln
+++ b/src/internal/internal.sln
@@ -9,6 +9,10 @@ Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "WixInternal.TestSupport.Nat
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WixInternal.BaseBuildTasks.Sources", "WixInternal.BaseBuildTasks.Sources\WixInternal.BaseBuildTasks.Sources.csproj", "{6B654490-AB0D-4F94-B564-DAA80044D5A3}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WixInternal.XunitTestSupport", "WixInternal.XunitTestSupport\WixInternal.XunitTestSupport.csproj", "{AF7C4730-583B-46F8-9BB6-16D1F0330932}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WixInternal.MSTestSupport", "WixInternal.MSTestSupport\WixInternal.MSTestSupport.csproj", "{E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}"
+EndProject
 Global
         GlobalSection(SolutionConfigurationPlatforms) = preSolution
                 Debug|Any CPU = Debug|Any CPU
@@ -65,6 +69,38 @@ Global
                 {6B654490-AB0D-4F94-B564-DAA80044D5A3}.Release|x64.Build.0 = Release|Any CPU
                 {6B654490-AB0D-4F94-B564-DAA80044D5A3}.Release|x86.ActiveCfg = Release|Any CPU
                 {6B654490-AB0D-4F94-B564-DAA80044D5A3}.Release|x86.Build.0 = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|Any CPU.Build.0 = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|ARM64.Build.0 = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|x64.ActiveCfg = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|x64.Build.0 = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|x86.ActiveCfg = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Debug|x86.Build.0 = Debug|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|Any CPU.ActiveCfg = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|Any CPU.Build.0 = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|ARM64.ActiveCfg = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|ARM64.Build.0 = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|x64.ActiveCfg = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|x64.Build.0 = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|x86.ActiveCfg = Release|Any CPU
+                {AF7C4730-583B-46F8-9BB6-16D1F0330932}.Release|x86.Build.0 = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|Any CPU.Build.0 = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|ARM64.Build.0 = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|x64.ActiveCfg = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|x64.Build.0 = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|x86.ActiveCfg = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Debug|x86.Build.0 = Debug|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|Any CPU.ActiveCfg = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|Any CPU.Build.0 = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|ARM64.ActiveCfg = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|ARM64.Build.0 = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|x64.ActiveCfg = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|x64.Build.0 = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|x86.ActiveCfg = Release|Any CPU
+                {E70898F2-8D08-4FCE-9CFF-EF1792FCA2E2}.Release|x86.Build.0 = Release|Any CPU
         EndGlobalSection
         GlobalSection(SolutionProperties) = preSolution
                 HideSolutionNode = FALSE
diff --git a/src/internal/internal_t.proj b/src/internal/internal_t.proj
index 7dd52354..ab96b6c8 100644
--- a/src/internal/internal_t.proj
+++ b/src/internal/internal_t.proj
@@ -2,6 +2,7 @@
   <ItemGroup>
     <ProjectReference Include="WixInternal.BaseBuildTasks.Sources\WixInternal.BaseBuildTasks.Sources.csproj" Targets="Pack" />
     <ProjectReference Include="WixInternal.TestSupport\WixInternal.TestSupport.csproj" Targets="Pack" />
+    <ProjectReference Include="WixInternal.MSTestSupport\WixInternal.MSTestSupport.csproj" Targets="Pack" />
     <ProjectReference Include="WixInternal.TestSupport.Native\WixInternal.TestSupport.Native.vcxproj" Properties="Platform=x86" />
     <ProjectReference Include="WixInternal.TestSupport.Native\WixInternal.TestSupport.Native.vcxproj" Properties="Platform=x64" />
   </ItemGroup>
diff --git a/src/wix.runsettings b/src/wix.runsettings
new file mode 100644
index 00000000..97e4acda
--- /dev/null
+++ b/src/wix.runsettings
@@ -0,0 +1,7 @@
+<RunSettings>
+  <MSTest>
+    <Parallelize>
+      <Scope>MethodLevel</Scope>
+    </Parallelize>
+  </MSTest>
+</RunSettings>
diff --git a/src/wix/WixInternal.Core.MSTestPackage/BundleExtractor.cs b/src/wix/WixInternal.Core.MSTestPackage/BundleExtractor.cs
new file mode 100644
index 00000000..c491ad56
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/BundleExtractor.cs
@@ -0,0 +1,156 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+    using System.Xml;
+    using WixToolset.Data.Burn;
+    using WixToolset.Extensibility.Services;
+
+    /// <summary>
+    /// Class to extract bundle contents for testing.
+    /// </summary>
+    public class BundleExtractor
+    {
+        private const string BurnNamespace = "http://wixtoolset.org/schemas/v4/2008/Burn";
+        private const string BADataFileName = "BootstrapperApplicationData.xml";
+        private const string BootstrapperExtensionDataFileName = "BootstrapperExtensionData.xml";
+
+        /// <summary>
+        /// Extracts the BA container.
+        /// </summary>
+        /// <param name="messaging"></param>
+        /// <param name="bundleFilePath">Path to the bundle.</param>
+        /// <param name="destinationFolderPath">Path to extract to.</param>
+        /// <param name="tempFolderPath">Temp path for extraction.</param>
+        /// <returns></returns>
+        public static ExtractBAContainerResult ExtractBAContainer(IMessaging messaging, string bundleFilePath, string destinationFolderPath, string tempFolderPath)
+        {
+            return ExtractAllContainers(messaging, bundleFilePath, destinationFolderPath, null, tempFolderPath);
+        }
+
+        /// <summary>
+        /// Extracts the BA container.
+        /// </summary>
+        /// <param name="messaging"></param>
+        /// <param name="bundleFilePath">Path to the bundle.</param>
+        /// <param name="baFolderPath">Path to extract BA to.</param>
+        /// <param name="otherContainersFolderPath">Optional path to extract other attached containers to.</param>
+        /// <param name="tempFolderPath">Temp path for extraction.</param>
+        /// <returns></returns>
+        public static ExtractBAContainerResult ExtractAllContainers(IMessaging messaging, string bundleFilePath, string baFolderPath, string otherContainersFolderPath, string tempFolderPath)
+        {
+            Directory.CreateDirectory(tempFolderPath);
+
+            var args = new List<string>
+            {
+                "burn", "extract",
+                "-intermediatefolder", tempFolderPath,
+                bundleFilePath,
+                "-oba", baFolderPath
+            };
+
+            if (!String.IsNullOrEmpty(otherContainersFolderPath))
+            {
+                args.Add("-o");
+                args.Add(otherContainersFolderPath);
+            }
+
+            var runnerResult = WixRunner.Execute(args.ToArray());
+
+            var result = new ExtractBAContainerResult();
+
+            if (runnerResult.ExitCode == 0)
+            {
+                result.Success = true;
+                result.ManifestDocument = LoadBurnManifest(baFolderPath);
+                result.ManifestNamespaceManager = GetBurnNamespaceManager(result.ManifestDocument, "burn");
+
+                result.BADataDocument = LoadBAData(baFolderPath);
+                result.BADataNamespaceManager = GetBADataNamespaceManager(result.BADataDocument, "ba");
+
+                result.BootstrapperExtensionDataDocument = LoadBootstrapperExtensionData(baFolderPath);
+                result.BootstrapperExtensionDataNamespaceManager = GetBootstrapperExtensionDataNamespaceManager(result.BootstrapperExtensionDataDocument, "be");
+            }
+
+            return result;
+        }
+
+        /// <summary>
+        /// Gets an <see cref="XmlNamespaceManager"/> for BootstrapperApplicationData.xml with the given prefix assigned to the root namespace.
+        /// </summary>
+        /// <param name="document"></param>
+        /// <param name="prefix"></param>
+        /// <returns></returns>
+        public static XmlNamespaceManager GetBADataNamespaceManager(XmlDocument document, string prefix)
+        {
+            var namespaceManager = new XmlNamespaceManager(document.NameTable);
+            namespaceManager.AddNamespace(prefix, BurnConstants.BootstrapperApplicationDataNamespace);
+            return namespaceManager;
+        }
+
+        /// <summary>
+        /// Gets an <see cref="XmlNamespaceManager"/> for BootstrapperExtensionData.xml with the given prefix assigned to the root namespace.
+        /// </summary>
+        /// <param name="document"></param>
+        /// <param name="prefix"></param>
+        /// <returns></returns>
+        public static XmlNamespaceManager GetBootstrapperExtensionDataNamespaceManager(XmlDocument document, string prefix)
+        {
+            var namespaceManager = new XmlNamespaceManager(document.NameTable);
+            namespaceManager.AddNamespace(prefix, BurnConstants.BootstrapperExtensionDataNamespace);
+            return namespaceManager;
+        }
+
+        /// <summary>
+        /// Gets an <see cref="XmlNamespaceManager"/> for the Burn manifest.xml with the given prefix assigned to the root namespace.
+        /// </summary>
+        /// <param name="document"></param>
+        /// <param name="prefix"></param>
+        /// <returns></returns>
+        public static XmlNamespaceManager GetBurnNamespaceManager(XmlDocument document, string prefix)
+        {
+            var namespaceManager = new XmlNamespaceManager(document.NameTable);
+            namespaceManager.AddNamespace(prefix, BurnNamespace);
+            return namespaceManager;
+        }
+
+        /// <summary>
+        /// Loads an XmlDocument with the BootstrapperApplicationData.xml from the given folder that contains the contents of the BA container.
+        /// </summary>
+        /// <param name="baFolderPath"></param>
+        /// <returns></returns>
+        public static XmlDocument LoadBAData(string baFolderPath)
+        {
+            var document = new XmlDocument();
+            document.Load(Path.Combine(baFolderPath, BADataFileName));
+            return document;
+        }
+
+        /// <summary>
+        /// Loads an XmlDocument with the BootstrapperApplicationData.xml from the given folder that contains the contents of the BA container.
+        /// </summary>
+        /// <param name="baFolderPath"></param>
+        /// <returns></returns>
+        public static XmlDocument LoadBootstrapperExtensionData(string baFolderPath)
+        {
+            var document = new XmlDocument();
+            document.Load(Path.Combine(baFolderPath, BootstrapperExtensionDataFileName));
+            return document;
+        }
+
+        /// <summary>
+        /// Loads an XmlDocument with the BootstrapperApplicationData.xml from the given folder that contains the contents of the BA container.
+        /// </summary>
+        /// <param name="baFolderPath"></param>
+        /// <returns></returns>
+        public static XmlDocument LoadBurnManifest(string baFolderPath)
+        {
+            var document = new XmlDocument();
+            document.Load(Path.Combine(baFolderPath, "manifest.xml"));
+            return document;
+        }
+    }
+}
diff --git a/src/wix/WixInternal.Core.MSTestPackage/ExtractBAContainerResult.cs b/src/wix/WixInternal.Core.MSTestPackage/ExtractBAContainerResult.cs
new file mode 100644
index 00000000..47759188
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/ExtractBAContainerResult.cs
@@ -0,0 +1,156 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System.Collections.Generic;
+    using System.IO;
+    using System.Xml;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+    /// <summary>
+    /// The result of extracting the BA container.
+    /// </summary>
+    public class ExtractBAContainerResult
+    {
+        /// <summary>
+        /// <see cref="XmlDocument"/> for BootstrapperExtensionData.xml.
+        /// </summary>
+        public XmlDocument BootstrapperExtensionDataDocument { get; set; }
+
+        /// <summary>
+        /// <see cref="XmlNamespaceManager"/> for BootstrapperExtensionData.xml.
+        /// </summary>
+        public XmlNamespaceManager BootstrapperExtensionDataNamespaceManager { get; set; }
+
+        /// <summary>
+        /// <see cref="XmlDocument"/> for BootstrapperApplicationData.xml.
+        /// </summary>
+        public XmlDocument BADataDocument { get; set; }
+
+        /// <summary>
+        /// <see cref="XmlNamespaceManager"/> for BootstrapperApplicationData.xml.
+        /// </summary>
+        public XmlNamespaceManager BADataNamespaceManager { get; set; }
+
+        /// <summary>
+        /// <see cref="XmlDocument"/> for the Burn manifest.xml.
+        /// </summary>
+        public XmlDocument ManifestDocument { get; set; }
+
+        /// <summary>
+        /// <see cref="XmlNamespaceManager"/> for the Burn manifest.xml.
+        /// </summary>
+        public XmlNamespaceManager ManifestNamespaceManager { get; set; }
+
+        /// <summary>
+        /// Whether extraction succeeded.
+        /// </summary>
+        public bool Success { get; set; }
+
+        /// <summary>
+        /// Whether attached containers extraction succeeded.
+        /// </summary>
+        public bool? AttachedContainersSuccess { get; set; }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <returns></returns>
+        public ExtractBAContainerResult AssertSuccess()
+        {
+            Assert.IsTrue(this.Success);
+            Assert.IsTrue(!this.AttachedContainersSuccess.HasValue || this.AttachedContainersSuccess.Value);
+            return this;
+        }
+
+        /// <summary>
+        /// Returns the relative path of the BA entry point dll in the given folder.
+        /// </summary>
+        /// <param name="extractedBAContainerFolderPath"></param>
+        /// <returns></returns>
+        public string GetBAFilePath(string extractedBAContainerFolderPath)
+        {
+            var uxPayloads = this.SelectManifestNodes("/burn:BurnManifest/burn:UX/burn:Payload");
+            var baPayload = uxPayloads[0];
+            var relativeBAPath = baPayload.Attributes["FilePath"].Value;
+            return Path.Combine(extractedBAContainerFolderPath, relativeBAPath);
+        }
+
+        /// <summary>
+        /// Returns the relative path of the BootstrapperExtension entry point dll in the given folder.
+        /// </summary>
+        /// <param name="extractedBAContainerFolderPath"></param>
+        /// <param name="extensionId"></param>
+        /// <returns></returns>
+        public string GetBootstrapperExtensionFilePath(string extractedBAContainerFolderPath, string extensionId)
+        {
+            var uxPayloads = this.SelectManifestNodes($"/burn:BurnManifest/burn:UX/burn:Payload[@Id='{extensionId}']");
+            var bextPayload = uxPayloads[0];
+            var relativeBextPath = bextPayload.Attributes["FilePath"].Value;
+            return Path.Combine(extractedBAContainerFolderPath, relativeBextPath);
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <param name="xpath">elements must have the 'ba' prefix</param>
+        /// <returns></returns>
+        public XmlNodeList SelectBADataNodes(string xpath)
+        {
+            return this.BADataDocument.SelectNodes(xpath, this.BADataNamespaceManager);
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <param name="xpath">elements must have the 'ba' prefix</param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public string[] GetBADataTestXmlLines(string xpath, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            return this.SelectBADataNodes(xpath).GetTestXmlLines(ignoredAttributesByElementName);
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <param name="xpath">elements must have the 'be' prefix</param>
+        /// <returns></returns>
+        public XmlNodeList SelectBootstrapperExtensionDataNodes(string xpath)
+        {
+            return this.BootstrapperExtensionDataDocument.SelectNodes(xpath, this.BootstrapperExtensionDataNamespaceManager);
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <param name="xpath">elements must have the 'be' prefix</param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public string[] GetBootstrapperExtensionTestXmlLines(string xpath, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            return this.SelectBootstrapperExtensionDataNodes(xpath).GetTestXmlLines(ignoredAttributesByElementName);
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <param name="xpath">elements must have the 'burn' prefix</param>
+        /// <returns></returns>
+        public XmlNodeList SelectManifestNodes(string xpath)
+        {
+            return this.ManifestDocument.SelectNodes(xpath, this.ManifestNamespaceManager);
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <param name="xpath">elements must have the 'burn' prefix</param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public string[] GetManifestTestXmlLines(string xpath, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            return this.SelectManifestNodes(xpath).GetTestXmlLines(ignoredAttributesByElementName);
+        }
+    }
+}
diff --git a/src/wix/WixInternal.Core.MSTestPackage/TestMessageListener.cs b/src/wix/WixInternal.Core.MSTestPackage/TestMessageListener.cs
new file mode 100644
index 00000000..d8bde43f
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/TestMessageListener.cs
@@ -0,0 +1,57 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System.Collections.Generic;
+    using WixToolset.Data;
+    using WixToolset.Extensibility;
+    using WixToolset.Extensibility.Services;
+
+    /// <summary>
+    /// An <see cref="IMessageListener"/> that simply stores all the messages.
+    /// </summary>
+    public sealed class TestMessageListener : IMessageListener
+    {
+        /// <summary>
+        /// All messages that have been received.
+        /// </summary>
+        public List<Message> Messages { get; } = new List<Message>();
+
+        /// <summary>
+        /// 
+        /// </summary>
+        public string ShortAppName => "TEST";
+
+        /// <summary>
+        /// 
+        /// </summary>
+        public string LongAppName => "Test";
+
+        /// <summary>
+        /// Stores the message in <see cref="Messages"/>.
+        /// </summary>
+        /// <param name="message"></param>
+        public void Write(Message message)
+        {
+            this.Messages.Add(message);
+        }
+
+        /// <summary>
+        /// Stores the message in <see cref="Messages"/>.
+        /// </summary>
+        /// <param name="message"></param>
+        public void Write(string message)
+        {
+            this.Messages.Add(new Message(null, MessageLevel.Information, 0, message));
+        }
+
+        /// <summary>
+        /// Always returns defaultMessageLevel.
+        /// </summary>
+        /// <param name="messaging"></param>
+        /// <param name="message"></param>
+        /// <param name="defaultMessageLevel"></param>
+        /// <returns></returns>
+        public MessageLevel CalculateMessageLevel(IMessaging messaging, Message message, MessageLevel defaultMessageLevel) => defaultMessageLevel;
+    }
+}
diff --git a/src/wix/WixInternal.Core.MSTestPackage/WixInternal.Core.MSTestPackage.csproj b/src/wix/WixInternal.Core.MSTestPackage/WixInternal.Core.MSTestPackage.csproj
new file mode 100644
index 00000000..6b4bbefe
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/WixInternal.Core.MSTestPackage.csproj
@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. -->
+
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFrameworks>net6.0;net472</TargetFrameworks>
+    <Description>Internal WiX Toolset MSTest Package</Description>
+    <DebugType>embedded</DebugType>
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <CreateDocumentationFile>true</CreateDocumentationFile>
+    <SignOutput>false</SignOutput>
+    <IsWixTestSupportProject>true</IsWixTestSupportProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\WixToolset.Core.Native\WixToolset.Core.Native.csproj" PrivateAssets="true" />
+    <ProjectReference Include="..\WixToolset.Core\WixToolset.Core.csproj" PrivateAssets="true" />
+    <ProjectReference Include="..\WixToolset.Core.Burn\WixToolset.Core.Burn.csproj" PrivateAssets="true" />
+    <ProjectReference Include="..\WixToolset.Core.ExtensionCache\WixToolset.Core.ExtensionCache.csproj" PrivateAssets="true" />
+    <ProjectReference Include="..\WixToolset.Core.WindowsInstaller\WixToolset.Core.WindowsInstaller.csproj" PrivateAssets="true" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="WixToolset.Data" />
+    <PackageReference Include="WixToolset.Extensibility" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="WixInternal.MSTestSupport" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="MSTest.TestFramework" />
+  </ItemGroup>
+</Project>
diff --git a/src/wix/WixInternal.Core.MSTestPackage/WixMessageFormatter.cs b/src/wix/WixInternal.Core.MSTestPackage/WixMessageFormatter.cs
new file mode 100644
index 00000000..c103f5d2
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/WixMessageFormatter.cs
@@ -0,0 +1,40 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System;
+    using WixToolset.Data;
+
+    /// <summary>
+    /// Utility class to help format messages.
+    /// </summary>
+    public static class WixMessageFormatter
+    {
+        /// <summary>
+        /// Formats a message into a standard string with the level, id, and message.
+        /// </summary>
+        /// <param name="message">Message to format</param>
+        /// <returns>Standard message formatting with the level, id, and message.</returns>
+        public static string FormatMessage(Message message)
+        {
+            return $"{message.Level} {message.Id}: {message}";
+        }
+
+        /// <summary>
+        /// Formats a message into a standard string with the level, id, and message.
+        /// </summary>
+        /// <param name="message">Message to format</param>
+        /// <param name="replacementMatch">Match for the replacement</param>
+        /// <param name="replacement">Value to replace</param>
+        /// <returns>Standard message formatting with the level, id, and message.</returns>
+        public static string FormatMessage(Message message, string replacementMatch, string replacement)
+        {
+            if (replacement is null)
+            {
+                throw new ArgumentNullException(nameof(replacement));
+            }
+
+            return $"{message.Level} {message.Id}: {message}".Replace(replacementMatch, replacement);
+        }
+    }
+}
diff --git a/src/wix/WixInternal.Core.MSTestPackage/WixRunner.cs b/src/wix/WixInternal.Core.MSTestPackage/WixRunner.cs
new file mode 100644
index 00000000..d83ba93e
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/WixRunner.cs
@@ -0,0 +1,90 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System.Collections.Generic;
+    using System.Threading;
+    using System.Threading.Tasks;
+    using WixToolset.Core;
+    using WixToolset.Core.Burn;
+    using WixToolset.Core.ExtensionCache;
+    using WixToolset.Core.WindowsInstaller;
+    using WixToolset.Data;
+    using WixToolset.Extensibility.Services;
+
+    /// <summary>
+    /// Utility class to emulate wix.exe with standard backends.
+    /// </summary>
+    public static class WixRunner
+    {
+        /// <summary>
+        /// Emulates calling wix.exe with standard backends.
+        /// </summary>
+        /// <param name="args"></param>
+        /// <param name="messages"></param>
+        /// <param name="warningsAsErrors"></param>
+        /// <returns></returns>
+        public static int Execute(string[] args, out List<Message> messages, bool warningsAsErrors = true)
+        {
+            var serviceProvider = WixToolsetServiceProviderFactory.CreateServiceProvider();
+            var task = Execute(args, serviceProvider, out messages, warningsAsErrors: warningsAsErrors);
+            return task.Result;
+        }
+
+        /// <summary>
+        /// Emulates calling wix.exe with standard backends.
+        /// This overload always treats warnings as errors.
+        /// </summary>
+        /// <param name="args"></param>
+        /// <returns></returns>
+        public static WixRunnerResult Execute(params string[] args)
+        {
+            return Execute(true, args);
+        }
+
+        /// <summary>
+        /// Emulates calling wix.exe with standard backends.
+        /// </summary>
+        /// <param name="warningsAsErrors"></param>
+        /// <param name="args"></param>
+        /// <returns></returns>
+        public static WixRunnerResult Execute(bool warningsAsErrors, params string[] args)
+        {
+            var serviceProvider = WixToolsetServiceProviderFactory.CreateServiceProvider();
+            var exitCode = Execute(args, serviceProvider, out var messages, warningsAsErrors: warningsAsErrors);
+            return new WixRunnerResult { ExitCode = exitCode.Result, Messages = messages.ToArray() };
+        }
+
+        /// <summary>
+        /// Emulates calling wix.exe with standard backends.
+        /// </summary>
+        /// <param name="args"></param>
+        /// <param name="coreProvider"></param>
+        /// <param name="messages"></param>
+        /// <param name="warningsAsErrors"></param>
+        /// <returns></returns>
+        public static Task<int> Execute(string[] args, IWixToolsetCoreServiceProvider coreProvider, out List<Message> messages, bool warningsAsErrors = true)
+        {
+            coreProvider.AddWindowsInstallerBackend()
+                        .AddBundleBackend()
+                        .AddExtensionCacheManager();
+
+            var listener = new TestMessageListener();
+
+            messages = listener.Messages;
+
+            var messaging = coreProvider.GetService<IMessaging>();
+            messaging.SetListener(listener);
+
+            var arguments = new List<string>(args);
+            if (warningsAsErrors)
+            {
+                arguments.Add("-wx");
+            }
+
+            var commandLine = coreProvider.GetService<ICommandLine>();
+            var command = commandLine.CreateCommand(arguments.ToArray());
+            return command?.ExecuteAsync(CancellationToken.None) ?? Task.FromResult(1);
+        }
+    }
+}
diff --git a/src/wix/WixInternal.Core.MSTestPackage/WixRunnerResult.cs b/src/wix/WixInternal.Core.MSTestPackage/WixRunnerResult.cs
new file mode 100644
index 00000000..4a8c784d
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/WixRunnerResult.cs
@@ -0,0 +1,62 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System;
+    using System.Collections.Generic;
+    using WixToolset.Data;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+    /// <summary>
+    /// The result of an Execute method of <see cref="WixRunner"/>.
+    /// </summary>
+    public class WixRunnerResult
+    {
+        /// <summary>
+        /// ExitCode for the operation.
+        /// </summary>
+        public int ExitCode { get; set; }
+
+        /// <summary>
+        /// Messages from the operation.
+        /// </summary>
+        public Message[] Messages { get; set; }
+
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <returns></returns>
+        public WixRunnerResult AssertSuccess()
+        {
+            AssertSuccess(this.ExitCode, this.Messages);
+            return this;
+        }
+
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="exitCode"></param>
+        /// <param name="messages"></param>
+        public static void AssertSuccess(int exitCode, IEnumerable<Message> messages)
+        {
+            Assert.IsTrue(0 == exitCode, $"\r\n\r\nWixRunner failed with exit code: {exitCode}\r\n   Output: {String.Join("\r\n           ", FormatMessages(messages))}\r\n");
+        }
+
+        private static IEnumerable<string> FormatMessages(IEnumerable<Message> messages)
+        {
+            foreach (var message in messages)
+            {
+                var filename = message.SourceLineNumbers?.FileName ?? "TEST";
+                var line = message.SourceLineNumbers?.LineNumber ?? -1;
+                var type = message.Level.ToString().ToLowerInvariant();
+
+                if (line > 0)
+                {
+                    filename = String.Concat(filename, "(", line, ")");
+                }
+
+                yield return String.Format("{0} : {1} {2}{3:0000}: {4}", filename, type, "TEST", message.Id, message.ToString());
+            }
+        }
+    }
+}
diff --git a/src/wix/WixInternal.Core.MSTestPackage/XmlNodeExtensions.cs b/src/wix/WixInternal.Core.MSTestPackage/XmlNodeExtensions.cs
new file mode 100644
index 00000000..11a7b209
--- /dev/null
+++ b/src/wix/WixInternal.Core.MSTestPackage/XmlNodeExtensions.cs
@@ -0,0 +1,115 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixInternal.Core.MSTestPackage
+{
+    using System.Collections.Generic;
+    using System.IO;
+    using System.Linq;
+    using System.Text.RegularExpressions;
+    using System.Xml;
+
+    /// <summary>
+    /// Utility class to help compare XML in tests using string comparisons by using single quotes and stripping all namespaces.
+    /// </summary>
+    public static class XmlNodeExtensions
+    {
+        /// <summary>
+        /// Adds root element around XML then returns it using single quotes and stripping all namespaces.
+        /// </summary>
+        /// <param name="xmlFragment"></param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public static string GetFragmentTestXml(this string xmlFragment, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            return $"<root>{xmlFragment}</root>".GetTestXml(ignoredAttributesByElementName);
+        }
+
+        /// <summary>
+        /// Returns the node's outer XML using single quotes and stripping all namespaces.
+        /// </summary>
+        /// <param name="node"></param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public static string GetTestXml(this XmlNode node, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            return node.OuterXml.GetTestXml(ignoredAttributesByElementName);
+        }
+
+        /// <summary>
+        /// Returns the XML using single quotes and stripping all namespaces.
+        /// </summary>
+        /// <param name="xml"></param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public static string GetTestXml(this string xml, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            string formattedXml;
+            using (var sw = new StringWriter())
+            using (var writer = new TestXmlWriter(sw))
+            {
+                var doc = new XmlDocument();
+                doc.LoadXml(xml);
+
+                if (ignoredAttributesByElementName != null)
+                {
+                    HandleIgnoredAttributes(doc, ignoredAttributesByElementName);
+                }
+
+                doc.Save(writer);
+                formattedXml = sw.ToString();
+            }
+
+            return Regex.Replace(formattedXml, " xmlns(:[^=]+)?='[^']*'", "");
+        }
+
+        /// <summary>
+        /// Returns the XML for each node using single quotes and stripping all namespaces.
+        /// </summary>
+        /// <param name="nodeList"></param>
+        /// <param name="ignoredAttributesByElementName">Attributes for which the value should be set to '*'.</param>
+        /// <returns></returns>
+        public static string[] GetTestXmlLines(this XmlNodeList nodeList, Dictionary<string, List<string>> ignoredAttributesByElementName = null)
+        {
+            return nodeList.Cast<XmlNode>()
+                           .Select(x => x.GetTestXml(ignoredAttributesByElementName))
+                           .ToArray();
+        }
+
+        private static void HandleIgnoredAttributes(XmlNode node, Dictionary<string, List<string>> ignoredAttributesByElementName)
+        {
+            if (node.Attributes != null && ignoredAttributesByElementName.TryGetValue(node.LocalName, out var ignoredAttributes))
+            {
+                foreach (var ignoredAttribute in ignoredAttributes)
+                {
+                    var attribute = node.Attributes[ignoredAttribute];
+                    if (attribute != null)
+                    {
+                        attribute.Value = "*";
+                    }
+                }
+            }
+
+            if (node.ChildNodes != null)
+            {
+                foreach (XmlNode childNode in node.ChildNodes)
+                {
+                    HandleIgnoredAttributes(childNode, ignoredAttributesByElementName);
+                }
+            }
+        }
+
+        private class TestXmlWriter : XmlTextWriter
+        {
+            public TestXmlWriter(TextWriter w)
+                : base(w)
+            {
+                this.QuoteChar = '\'';
+            }
+
+            public override void WriteStartDocument()
+            {
+                //OmitXmlDeclaration
+            }
+        }
+    }
+}
diff --git a/src/wix/pack_t.proj b/src/wix/pack_t.proj
index cd2cf634..7090f19b 100644
--- a/src/wix/pack_t.proj
+++ b/src/wix/pack_t.proj
@@ -8,6 +8,7 @@
     <ProjectReference Include="WixToolset.Core.Burn\WixToolset.Core.Burn.csproj" Properties="NoBuild=true" Targets="Pack" />
     <ProjectReference Include="WixToolset.Core.ExtensionCache\WixToolset.Core.ExtensionCache.csproj" Properties="NoBuild=true" Targets="Pack" />
     <ProjectReference Include="WixInternal.Core.TestPackage\WixInternal.Core.TestPackage.csproj" Properties="NoBuild=true" Targets="Pack" />
+    <ProjectReference Include="WixInternal.Core.MSTestPackage\WixInternal.Core.MSTestPackage.csproj" Properties="NoBuild=true" Targets="Pack" />
     <ProjectReference Include="WixToolset.Core.WindowsInstaller\WixToolset.Core.WindowsInstaller.csproj" Properties="NoBuild=true" Targets="Pack" />
 
     <ProjectReference Include="WixToolset.Converters\WixToolset.Converters.csproj" Properties="NoBuild=true" Targets="Pack" />
diff --git a/src/wix/wix.sln b/src/wix/wix.sln
index f64b22c0..7eec8e8a 100644
--- a/src/wix/wix.sln
+++ b/src/wix/wix.sln
@@ -48,6 +48,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "pack-wix", "pack-wix\pack-w
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WixToolsetTest.Core", "test\WixToolsetTest.Core\WixToolsetTest.Core.csproj", "{392817AE-4493-4BED-A7FD-2399379E1B1C}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WixInternal.Core.MSTestPackage", "WixInternal.Core.MSTestPackage\WixInternal.Core.MSTestPackage.csproj", "{61003299-4D78-4291-862C-73806C62C3BD}"
+EndProject
 Global
         GlobalSection(SolutionConfigurationPlatforms) = preSolution
                 Debug|Any CPU = Debug|Any CPU
@@ -412,6 +414,22 @@ Global
                 {392817AE-4493-4BED-A7FD-2399379E1B1C}.Release|x64.Build.0 = Release|Any CPU
                 {392817AE-4493-4BED-A7FD-2399379E1B1C}.Release|x86.ActiveCfg = Release|Any CPU
                 {392817AE-4493-4BED-A7FD-2399379E1B1C}.Release|x86.Build.0 = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|Any CPU.Build.0 = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|ARM64.Build.0 = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|x64.ActiveCfg = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|x64.Build.0 = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|x86.ActiveCfg = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Debug|x86.Build.0 = Debug|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|Any CPU.ActiveCfg = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|Any CPU.Build.0 = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|ARM64.ActiveCfg = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|ARM64.Build.0 = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|x64.ActiveCfg = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|x64.Build.0 = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|x86.ActiveCfg = Release|Any CPU
+                {61003299-4D78-4291-862C-73806C62C3BD}.Release|x86.Build.0 = Release|Any CPU
         EndGlobalSection
         GlobalSection(SolutionProperties) = preSolution
                 HideSolutionNode = FALSE