reactivemarbles · ChrisPulman · Jul 5, 2026 · Jul 5, 2026
diff --git a/Directory.Packages.props b/Directory.Packages.props
@@ -35,6 +35,7 @@
     <PackageVersion Include="ReactiveUI.Maui" Version="24.0.0-beta.3" />
     <PackageVersion Include="ReactiveUI.Primitives" Version="6.0.0" />
     <PackageVersion Include="ReactiveUI.Primitives.Core" Version="6.0.0" />
+    <PackageVersion Include="ReactiveUI.Primitives.Reactive" Version="6.0.0" />
     <PackageVersion Include="ReactiveUI.WinForms" Version="24.0.0-beta.3" />
     <PackageVersion Include="ReactiveUI.WinUI" Version="24.0.0-beta.3" />
     <PackageVersion Include="ReactiveUI.WPF" Version="24.0.0-beta.3" />

diff --git a/src/Extensions.Hosting.Avalonia/Internals/AvaloniaThread.cs b/src/Extensions.Hosting.Avalonia/Internals/AvaloniaThread.cs
@@ -6,7 +6,6 @@
 using System.Linq;
 using Avalonia;
 using Avalonia.Controls;
-using Avalonia.Controls.ApplicationLifetimes;
 using Microsoft.Extensions.DependencyInjection;
 using ReactiveMarbles.Extensions.Hosting.UiThread;
 

diff --git a/src/Extensions.Hosting.MainUIThread/BaseUiThread.cs b/src/Extensions.Hosting.MainUIThread/BaseUiThread.cs
@@ -61,7 +61,11 @@ protected BaseUiThread(IServiceProvider serviceProvider, bool useDedicatedUiThre
             IsBackground = true
         };
 
+#if NET5_0_OR_GREATER
+        if (OperatingSystem.IsWindows())
+#else
         if (Environment.OSVersion.Platform == PlatformID.Win32NT)
+#endif
         {
             // Set the apartment state for Windows desktop UI frameworks.
             newUiThread.SetApartmentState(ApartmentState.STA);

diff --git a/src/Extensions.Hosting.Plugins.Reactive/Extensions.Hosting.Plugins.Reactive.csproj b/src/Extensions.Hosting.Plugins.Reactive/Extensions.Hosting.Plugins.Reactive.csproj
@@ -0,0 +1,30 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>net462;net472;net48;net481;net8.0;net9.0;net10.0;net11.0</TargetFrameworks>
+    <PackageDescription>This extension adds reactive plug-in support to generic host based applications.</PackageDescription>
+    <PackageId>CP.Extensions.Hosting.Plugins.Reactive</PackageId>
+    <DefineConstants>$(DefineConstants);REACTIVE_SHIM</DefineConstants>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Compile Include="..\Extensions.Hosting.Plugins\**\*.cs" Exclude="..\Extensions.Hosting.Plugins\bin\**;..\Extensions.Hosting.Plugins\obj\**" Link="%(RecursiveDir)%(Filename)%(Extension)" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.FileSystemGlobbing" />
+    <PackageReference Include="Microsoft.Extensions.Hosting" />
+    <PackageReference Include="ReactiveUI.Primitives.Reactive" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Using Include="ReactiveUI.Primitives.Disposables.MultipleDisposable" Alias="CompositeDisposable" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
+      <_Parameter1>Extensions.Hosting.Tests</_Parameter1>
+    </AssemblyAttribute>
+  </ItemGroup>
+
+</Project>
diff --git a/src/Extensions.Hosting.Plugins/HostBuilderPluginExtensions.cs b/src/Extensions.Hosting.Plugins/HostBuilderPluginExtensions.cs
@@ -9,9 +9,17 @@
 using System.Reflection;
 using Microsoft.Extensions.FileSystemGlobbing;
 using Microsoft.Extensions.Hosting;
+#if REACTIVE_SHIM
+using ReactiveMarbles.Extensions.Hosting.Reactive.Plugins.Internals;
+#else
 using ReactiveMarbles.Extensions.Hosting.Plugins.Internals;
+#endif
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides extension methods for configuring and loading plugins in host builder pipelines.</summary>
 /// <remarks>These extension methods enable plugin discovery and configuration for applications using IHostBuilder
@@ -200,7 +208,7 @@ private static void LoadFrameworkAssemblies(IPluginBuilder pluginBuilder, HashSe
                     continue;
                 }
 
-                var loadedAssembly = AssemblyLoadContext.Default.LoadFromAssemblyPath(frameworkAssemblyPath);
+                var loadedAssembly = AssemblyLoadContext.LoadFromAssemblyPath(frameworkAssemblyPath);
                 _ = scannedAssemblies.Add(loadedAssembly);
             }
         }

diff --git a/src/Extensions.Hosting.Plugins/HostedServiceBase.cs b/src/Extensions.Hosting.Plugins/HostedServiceBase.cs
@@ -8,7 +8,11 @@
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides a base implementation for a hosted service with support for resource cleanup, logging, and application lifetime events.</summary>
 /// <remarks>This base class integrates with the application's lifetime events to manage service startup,

diff --git a/src/Extensions.Hosting.Plugins/IPlugin.cs b/src/Extensions.Hosting.Plugins/IPlugin.cs
@@ -4,7 +4,11 @@
 
 using Microsoft.Extensions.DependencyInjection;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Defines a contract for plug-ins that can configure services and settings for the application host during startup.</summary>
 /// <remarks>Implementations of this interface can be used to extend or modify the application's dependency

diff --git a/src/Extensions.Hosting.Plugins/IPluginBuilder.cs b/src/Extensions.Hosting.Plugins/IPluginBuilder.cs
@@ -7,7 +7,11 @@
 using System.Reflection;
 using Microsoft.Extensions.FileSystemGlobbing;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Defines a contract for configuring and building plugin discovery and loading behavior within an application.</summary>
 /// <remarks>Implementations of this interface allow customization of plugin and framework assembly scanning,

diff --git a/src/Extensions.Hosting.Plugins/Internals/AssemblyDependencyResolver.cs b/src/Extensions.Hosting.Plugins/Internals/AssemblyDependencyResolver.cs
@@ -6,7 +6,11 @@
 using System.IO;
 using System.Reflection;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins.Internals;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins.Internals;
+#endif
 
 /// <summary>Provides methods for resolving the paths of managed assemblies and unmanaged DLLs relative to a specified plugin directory.</summary>
 /// <param name="pluginPath">The absolute path to the root directory containing the plugin and its dependencies. Cannot be null or empty.</param>

diff --git a/src/Extensions.Hosting.Plugins/Internals/AssemblyLoadContext.cs b/src/Extensions.Hosting.Plugins/Internals/AssemblyLoadContext.cs
@@ -6,7 +6,11 @@
 using System.Collections.Generic;
 using System.Reflection;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins.Internals;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins.Internals;
+#endif
 
 /// <summary>Provides functionality for loading and managing assemblies in a custom context, enabling isolation and control over assembly loading behavior.</summary>
 /// <remarks>AssemblyLoadContext allows applications to load assemblies into isolated contexts, which can be
@@ -24,11 +28,19 @@ public class AssemblyLoadContext(string name)
     /// this property to access the standard assembly loading behavior provided by .NET.</remarks>
     public static AssemblyLoadContext Default { get; } = new AssemblyLoadContext("default");
 
+    /// <summary>Gets the assemblies that are loaded into the current application domain.</summary>
+    public static IEnumerable<Assembly> Assemblies => AppDomain.CurrentDomain.GetAssemblies();
+
     /// <summary>Gets the name associated with the current instance.</summary>
     public string Name { get; } = name;
 
-    /// <summary>Gets the assemblies that are loaded into the current application domain.</summary>
-    public IEnumerable<Assembly> Assemblies => AppDomain.CurrentDomain.GetAssemblies();
+    /// <summary>Loads an assembly from the specified file path.</summary>
+    /// <remarks>The assembly is loaded into the load-from context. If the assembly has already been loaded,
+    /// this method may return a reference to the existing assembly. This method does not resolve dependencies
+    /// automatically; dependent assemblies must be available to the loader.</remarks>
+    /// <param name="assemblyPath">The path to the assembly file to load. The path must be a valid file system path to a managed assembly file.</param>
+    /// <returns>The loaded assembly represented by the specified file path.</returns>
+    public static Assembly LoadFromAssemblyPath(string assemblyPath) => Assembly.LoadFrom(assemblyPath);
 
     /// <summary>Loads an assembly given its display name.</summary>
     /// <remarks>This method loads the assembly into the current load context. If the assembly has already
@@ -47,27 +59,19 @@ public Assembly LoadFromAssemblyName(AssemblyName assemblyName)
         return Load(assemblyName);
     }
 
-    /// <summary>Loads an assembly from the specified file path.</summary>
-    /// <remarks>The assembly is loaded into the load-from context. If the assembly has already been loaded,
-    /// this method may return a reference to the existing assembly. This method does not resolve dependencies
-    /// automatically; dependent assemblies must be available to the loader.</remarks>
-    /// <param name="assemblyPath">The path to the assembly file to load. The path must be a valid file system path to a managed assembly file.</param>
-    /// <returns>The loaded assembly represented by the specified file path.</returns>
-    public Assembly LoadFromAssemblyPath(string assemblyPath) => Assembly.LoadFrom(assemblyPath);
-
-    /// <summary>Loads the assembly with the specified name.</summary>
-    /// <remarks>Override this method to implement custom assembly loading logic in a derived class.</remarks>
-    /// <param name="assemblyName">The name of the assembly to load. Cannot be null.</param>
-    /// <returns>The loaded assembly, or null if the assembly cannot be found.</returns>
-    protected virtual Assembly Load(AssemblyName assemblyName) => null!;
-
     /// <summary>Loads an unmanaged dynamic-link library (DLL) from the specified absolute path.</summary>
     /// <remarks>This method is intended to be called by derived classes to provide custom logic for loading
     /// unmanaged libraries. The caller is responsible for ensuring that the specified path points to a valid and
     /// compatible DLL.</remarks>
     /// <param name="dllPath">The absolute path to the unmanaged DLL to load. Cannot be null or empty.</param>
     /// <returns>A handle to the loaded unmanaged DLL. Returns <see cref="IntPtr.Zero"/> if the library could not be loaded.</returns>
-    protected IntPtr LoadUnmanagedDllFromPath(string dllPath) => IntPtr.Zero;
+    protected static IntPtr LoadUnmanagedDllFromPath(string dllPath) => IntPtr.Zero;
+
+    /// <summary>Loads the assembly with the specified name.</summary>
+    /// <remarks>Override this method to implement custom assembly loading logic in a derived class.</remarks>
+    /// <param name="assemblyName">The name of the assembly to load. Cannot be null.</param>
+    /// <returns>The loaded assembly, or null if the assembly cannot be found.</returns>
+    protected virtual Assembly Load(AssemblyName assemblyName) => null!;
 
     /// <summary>Loads the specified unmanaged DLL into the process address space.</summary>
     /// <remarks>Override this method to provide custom logic for loading unmanaged libraries when resolving

diff --git a/src/Extensions.Hosting.Plugins/Internals/AssemblyLoadContextExtensions.cs b/src/Extensions.Hosting.Plugins/Internals/AssemblyLoadContextExtensions.cs
@@ -4,7 +4,11 @@
 
 using System.Reflection;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins.Internals;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins.Internals;
+#endif
 
 /// <summary>Provides extension methods for the AssemblyLoadContext class.</summary>
 /// <remarks>This static class contains methods that extend the functionality of AssemblyLoadContext, enabling
@@ -32,7 +36,7 @@ public bool TryGetAssembly(AssemblyName assemblyName, out Assembly? foundAssembl
                 return false;
             }
 
-            foreach (var assembly in assemblyLoadContext.Assemblies)
+            foreach (var assembly in AssemblyLoadContext.Assemblies)
             {
                 var name = assembly.GetName().Name;
                 if (name is null)

diff --git a/src/Extensions.Hosting.Plugins/Internals/PluginBuilder.cs b/src/Extensions.Hosting.Plugins/Internals/PluginBuilder.cs
@@ -7,7 +7,11 @@
 using System.Reflection;
 using Microsoft.Extensions.FileSystemGlobbing;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins.Internals;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins.Internals;
+#endif
 
 /// <summary>Provides configuration and matching logic for plugin discovery and loading within the application.</summary>
 /// <remarks>The PluginBuilder class exposes properties and delegates that allow customization of plugin scanning,

diff --git a/src/Extensions.Hosting.Plugins/Internals/PluginLoadContext.cs b/src/Extensions.Hosting.Plugins/Internals/PluginLoadContext.cs
@@ -5,7 +5,11 @@
 using System;
 using System.Reflection;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins.Internals;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins.Internals;
+#endif
 
 /// <summary>Provides an isolated assembly load context for loading plugins from a specified directory.</summary>
 /// <remarks>PluginLoadContext enables loading and resolving assemblies and unmanaged libraries for plugins
@@ -45,6 +49,6 @@ protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
     private Assembly? LoadAssemblyFromResolvedPath(AssemblyName assemblyName)
     {
         var assemblyPath = ResolveAssemblyPath(assemblyName);
-        return assemblyPath is null ? null : LoadFromAssemblyPath(assemblyPath);
+        return assemblyPath is null ? null : AssemblyLoadContext.LoadFromAssemblyPath(assemblyPath);
     }
 }
diff --git a/src/Extensions.Hosting.Plugins/PluginBase{T1,T2,T3}.cs b/src/Extensions.Hosting.Plugins/PluginBase{T1,T2,T3}.cs
@@ -5,7 +5,11 @@
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides a base implementation for plugins that register three hosted services with the application host.</summary>
 /// <remarks>This class is intended to be used as a base for plugins that require multiple hosted services to be

diff --git a/src/Extensions.Hosting.Plugins/PluginBase{T1,T2}.cs b/src/Extensions.Hosting.Plugins/PluginBase{T1,T2}.cs
@@ -5,7 +5,11 @@
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides a base implementation for plugins that register two hosted services with a dependency injection container.</summary>
 /// <remarks>This class is intended to be used as a base for plugins that require multiple hosted services to be

diff --git a/src/Extensions.Hosting.Plugins/PluginBase{T}.cs b/src/Extensions.Hosting.Plugins/PluginBase{T}.cs
@@ -5,7 +5,11 @@
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides a base implementation for plugins that register a hosted service of the specified type with the application's dependency injection container.</summary>
 /// <typeparam name="T">The type of the hosted service to register. Must implement <see cref="IHostedService"/>.</typeparam>

diff --git a/src/Extensions.Hosting.Plugins/PluginBuilderExtensions.cs b/src/Extensions.Hosting.Plugins/PluginBuilderExtensions.cs
@@ -5,7 +5,11 @@
 using System;
 using System.IO;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides extension methods for configuring plug-in and framework assembly scanning behavior on an <see cref="IPluginBuilder"/> instance.</summary>
 /// <remarks>These extension methods allow customization of directory scanning, inclusion and exclusion patterns

diff --git a/src/Extensions.Hosting.Plugins/PluginOrderAttribute.cs b/src/Extensions.Hosting.Plugins/PluginOrderAttribute.cs
@@ -4,7 +4,11 @@
 
 using System;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Specifies the initialization order for a plug-in class.</summary>
 /// <remarks>Apply this attribute to a plug-in class to control the sequence in which plug-ins are initialized.

diff --git a/src/Extensions.Hosting.Plugins/PluginScanner.cs b/src/Extensions.Hosting.Plugins/PluginScanner.cs
@@ -6,7 +6,11 @@
 using System.Collections.Generic;
 using System.Reflection;
 
+#if REACTIVE_SHIM
+namespace ReactiveMarbles.Extensions.Hosting.Reactive.Plugins;
+#else
 namespace ReactiveMarbles.Extensions.Hosting.Plugins;
+#endif
 
 /// <summary>Provides methods for discovering and instantiating plugin implementations from assemblies using naming conventions or type scanning.</summary>
 /// <remarks>The PluginScanner class is intended for use in scenarios where plugins implementing the IPlugin

diff --git a/src/Extensions.Hosting.SingleInstance/Extensions.Hosting.SingleInstance.csproj b/src/Extensions.Hosting.SingleInstance/Extensions.Hosting.SingleInstance.csproj
@@ -10,4 +10,10 @@
     <PackageReference Include="Microsoft.Extensions.Hosting" />
   </ItemGroup>
 
+  <ItemGroup>
+    <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
+      <_Parameter1>Extensions.Hosting.Tests</_Parameter1>
+    </AssemblyAttribute>
+  </ItemGroup>
+
 </Project>