diff --git a/Directory.Build.props b/Directory.Build.props
index 7a79159f2355e9..e1c32d0a2d31be 100644
--- a/Directory.Build.props
+++ b/Directory.Build.props
@@ -218,6 +218,10 @@
     <MicrosoftNetCoreAppRuntimePackNativeDir>$([MSBuild]::NormalizeDirectory('$(MicrosoftNetCoreAppRuntimePackRidDir)', 'native'))</MicrosoftNetCoreAppRuntimePackNativeDir>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <DotNetHostBinDir>$([MSBuild]::NormalizeDirectory('$(ArtifactsBinDir)', '$(OutputRid).$(Configuration)', 'corehost'))</DotNetHostBinDir>
+  </PropertyGroup>
+
   <!--Feature switches -->
   <PropertyGroup>
     <EnableNgenOptimization Condition="'$(EnableNgenOptimization)' == '' and ('$(Configuration)' == 'Release' or '$(Configuration)' == 'Checked')">true</EnableNgenOptimization>
diff --git a/eng/Subsets.props b/eng/Subsets.props
index 7113a4ac779e33..4abf2106981e3e 100644
--- a/eng/Subsets.props
+++ b/eng/Subsets.props
@@ -120,7 +120,14 @@
     <SubsetName Include="Mono.WasmRuntime" Description="The WebAssembly runtime." />
     <SubsetName Include="Mono.MsCorDbi" Description="The implementation of ICorDebug interface." />
     <SubsetName Include="Mono.Workloads" OnDemand="true" Description="Builds the installers and the insertion metadata for Blazor workloads." />
-    
+
+    <!-- Host -->
+    <SubsetName Include="Host" Description="The .NET hosts, packages, hosting libraries, and tests." />
+    <SubsetName Include="Host.Native" Description="The .NET hosts." />
+    <SubsetName Include="Host.Pkg" Description="The .NET host packages." />
+    <SubsetName Include="Host.Tools" Description="The .NET hosting libraries." />
+    <SubsetName Include="Host.Tests" Description="The .NET hosting tests." />
+
     <!-- Libs -->
     <SubsetName Include="Libs" Description="The libraries native part, refs and source assemblies, test infra and packages, but NOT the tests (use Libs.Tests to request those explicitly)" />
     <SubsetName Include="Libs.Native" Description="The native libraries used in the shared framework." />
@@ -130,13 +137,6 @@
     <SubsetName Include="Libs.Packages" Description="The projects that produce NuGet packages from libraries." />
     <SubsetName Include="Libs.Tests" OnDemand="true" Description="The test projects. Note that building this doesn't execute tests: you must also pass the '-test' argument." />
 
-    <!-- Host -->
-    <SubsetName Include="Host" Description="The .NET hosts, packages, hosting libraries, and tests." />
-    <SubsetName Include="Host.Native" Description="The .NET hosts." />
-    <SubsetName Include="Host.Pkg" Description="The .NET host packages." />
-    <SubsetName Include="Host.Tools" Description="The .NET hosting libraries." />
-    <SubsetName Include="Host.Tests" Description="The .NET hosting tests." />
-
     <!-- Packs -->
     <SubsetName Include="Packs" Description="Builds the shared framework packs, archives, bundles, installers, and the framework pack tests." />
     <SubsetName Include="Packs.Product" Description="Builds the shared framework packs, archives, bundles, and installers." />
@@ -264,6 +264,22 @@
     <ProjectToBuild Include="$(WorkloadsProjectRoot)\workloads.csproj" Category="mono" />
   </ItemGroup>
 
+  <!-- Host sets -->
+  <ItemGroup Condition="$(_subset.Contains('+host.native+'))">
+    <CorehostProjectToBuild Include="$(SharedNativeRoot)corehost\corehost.proj" SignPhase="Binaries" BuildInParallel="false" />
+    <ProjectToBuild Include="@(CorehostProjectToBuild)" Pack="true" Category="host" />
+  </ItemGroup>
+
+  <ItemGroup Condition="$(_subset.Contains('+host.tools+'))">
+    <ManagedProjectToBuild Include="$(InstallerProjectRoot)managed\**\*.csproj" SignPhase="Binaries" />
+    <ProjectToBuild Include="@(ManagedProjectToBuild)" BuildInParallel="true" Pack="true" Category="host" />
+  </ItemGroup>
+
+  <ItemGroup Condition="$(_subset.Contains('+host.pkg+')) and '$(PgoInstrument)' != 'true'">
+    <PkgprojProjectToBuild Include="$(InstallerProjectRoot)pkg\projects\host-packages.proj" SignPhase="MsiFiles" BuildInParallel="false" />
+    <ProjectToBuild Include="@(PkgprojProjectToBuild)" Pack="true" Category="host" />
+  </ItemGroup>
+
   <!-- Libraries sets -->
   <ItemGroup Condition="$(_subset.Contains('+libs.native+'))">
     <ProjectToBuild Include="$(LibrariesProjectRoot)Native\build-native.proj" Category="libs" />
@@ -289,22 +305,7 @@
     <ProjectToBuild Include="$(LibrariesProjectRoot)tests.proj" Category="libs" Test="true" />
   </ItemGroup>
 
-  <!-- Host sets -->
-  <ItemGroup Condition="$(_subset.Contains('+host.native+'))">
-    <CorehostProjectToBuild Include="$(SharedNativeRoot)corehost\corehost.proj" SignPhase="Binaries" BuildInParallel="false" />
-    <ProjectToBuild Include="@(CorehostProjectToBuild)" Pack="true" Category="host" />
-  </ItemGroup>
-
-  <ItemGroup Condition="$(_subset.Contains('+host.tools+'))">
-    <ManagedProjectToBuild Include="$(InstallerProjectRoot)managed\**\*.csproj" SignPhase="Binaries" />
-    <ProjectToBuild Include="@(ManagedProjectToBuild)" BuildInParallel="true" Pack="true" Category="host" />
-  </ItemGroup>
-
-  <ItemGroup Condition="$(_subset.Contains('+host.pkg+')) and '$(PgoInstrument)' != 'true'">
-    <PkgprojProjectToBuild Include="$(InstallerProjectRoot)pkg\projects\host-packages.proj" SignPhase="MsiFiles" BuildInParallel="false" />
-    <ProjectToBuild Include="@(PkgprojProjectToBuild)" Pack="true" Category="host" />
-  </ItemGroup>
-
+  <!-- Host.tests subset (consumes live built libraries assets so needs to come after libraries) -->
   <ItemGroup Condition="$(_subset.Contains('+host.tests+'))">
     <TestProjectToBuild Include="$(InstallerProjectRoot)tests\Microsoft.NET.HostModel.Tests\AppHost.Bundle.Tests\AppHost.Bundle.Tests.csproj" />
     <TestProjectToBuild Include="$(InstallerProjectRoot)tests\Microsoft.NET.HostModel.Tests\Microsoft.NET.HostModel.AppHost.Tests\Microsoft.NET.HostModel.AppHost.Tests.csproj" />
diff --git a/src/installer/pkg/Directory.Build.props b/src/installer/pkg/Directory.Build.props
index 10f36b399c73b6..f51718676368a2 100644
--- a/src/installer/pkg/Directory.Build.props
+++ b/src/installer/pkg/Directory.Build.props
@@ -3,7 +3,6 @@
 
   <PropertyGroup>
     <Platform>$(TargetArchitecture)</Platform>
-    <DotNetHostBinDir>$(ArtifactsBinDir)$(OutputRid).$(Configuration)\corehost</DotNetHostBinDir>
   </PropertyGroup>
 
   <PropertyGroup>
diff --git a/src/libraries/externals.csproj b/src/libraries/externals.csproj
index 6ef3ddc0f19015..969ed9603a2cda 100644
--- a/src/libraries/externals.csproj
+++ b/src/libraries/externals.csproj
@@ -9,6 +9,7 @@
     <BinPlaceNative>true</BinPlaceNative>
     <BinPlaceRuntime>false</BinPlaceRuntime>
     <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
+    <UseLiveBuiltDotNetHost Condition="'$(TargetArchitecture)' == 's390x'">true</UseLiveBuiltDotNetHost>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(DotNetBuildFromSource)' != 'true'">
@@ -16,7 +17,7 @@
                       Version="$(MicrosoftDiaSymReaderNativeVersion)" />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(TargetsMobile)' != 'true'">
+  <ItemGroup Condition="'$(TargetsMobile)' != 'true' and '$(UseLiveBuiltDotNetHost)' != 'true'">
     <PackageReference Include="Microsoft.NETCore.DotNetHost"
                       Version="$(MicrosoftNETCoreDotNetHostVersion)" />
     <PackageReference Include="Microsoft.NETCore.DotNetHostPolicy"
@@ -38,17 +39,31 @@
       <ReferenceCopyLocalPaths Remove="@(ReferenceCopyLocalPaths)" Condition="'%(Filename)' == 'apphost'" />
     </ItemGroup>
 
-    <ItemGroup>
+    <ItemGroup Condition="'$(UseLiveBuiltDotNetHost)' != 'true'">
       <HostFxFile Include="@(ReferenceCopyLocalPaths)" Condition="'%(ReferenceCopyLocalPaths.Filename)' == 'hostfxr' or
                                                                   '%(ReferenceCopyLocalPaths.Filename)' == 'libhostfxr'" />
       <DotnetExe Include="@(ReferenceCopyLocalPaths)" Condition="'%(ReferenceCopyLocalPaths.Filename)' == 'dotnet'" />
     </ItemGroup>
 
+    <ItemGroup Condition="'$(UseLiveBuiltDotNetHost)' == 'true'">
+      <CoreHostFiles Include="$(DotNetHostBinDir)*" />
+      <HostFxFile Include="@(CoreHostFiles)" Condition="'%(CoreHostFiles.Filename)' == 'hostfxr' or
+                                                          '%(CoreHostFiles.Filename)' == 'libhostfxr'" />
+      <HostPolicyFile Include="@(CoreHostFiles)" Condition="'%(CoreHostFiles.Filename)' == 'hostpolicy' or
+                                                              '%(CoreHostFiles.Filename)' == 'libhostpolicy'" />
+      <DotnetExe Include="@(CoreHostFiles)" Condition="'%(CoreHostFiles.Filename)' == 'dotnet'" />
+    </ItemGroup>
+
     <Copy SourceFiles="@(HostFxFile)"
           DestinationFolder="$(NetCoreAppCurrentTestHostPath)host\fxr\$(ProductVersion)"
           SkipUnchangedFiles="true"
           UseHardlinksIfPossible="$(UseHardlink)" />
 
+    <Copy SourceFiles="@(HostPolicyFile)"
+          DestinationFolder="$(NetCoreAppCurrentTestHostPath)shared\Microsoft.NETCore.App\$(ProductVersion)"
+          SkipUnchangedFiles="true"
+          UseHardlinksIfPossible="$(UseHardlink)" />
+
     <Copy SourceFiles="@(DotnetExe)"
           DestinationFolder="$(NetCoreAppCurrentTestHostPath)"
           SkipUnchangedFiles="true"