diff --git a/src/ReactiveUI.AOTTests/AOTCompatibilityTests.cs b/src/ReactiveUI.AOTTests/AOTCompatibilityTests.cs
index 48b6c0f8ad..aafd83ec7b 100644
--- a/src/ReactiveUI.AOTTests/AOTCompatibilityTests.cs
+++ b/src/ReactiveUI.AOTTests/AOTCompatibilityTests.cs
@@ -3,9 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
-using System.Reactive.Linq;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>
diff --git a/src/ReactiveUI.AOTTests/AdvancedAOTTests.cs b/src/ReactiveUI.AOTTests/AdvancedAOTTests.cs
index 92ee4cac4c..e2fd8f9fed 100644
--- a/src/ReactiveUI.AOTTests/AdvancedAOTTests.cs
+++ b/src/ReactiveUI.AOTTests/AdvancedAOTTests.cs
@@ -3,11 +3,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using System.Reactive.Disposables;
-using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using Splat;
 
 namespace ReactiveUI.AOTTests;
 
diff --git a/src/ReactiveUI.AOTTests/AssemblyInfo.Parallel.cs b/src/ReactiveUI.AOTTests/AssemblyInfo.Parallel.cs
index 9516e8d004..eb6214b15b 100644
--- a/src/ReactiveUI.AOTTests/AssemblyInfo.Parallel.cs
+++ b/src/ReactiveUI.AOTTests/AssemblyInfo.Parallel.cs
@@ -3,7 +3,5 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using NUnit.Framework;
-
 [assembly: Parallelizable(ParallelScope.Fixtures)]
 [assembly: LevelOfParallelism(4)]
\ No newline at end of file
diff --git a/src/ReactiveUI.AOTTests/ComprehensiveAOTMarkupTests.cs b/src/ReactiveUI.AOTTests/ComprehensiveAOTMarkupTests.cs
index 9e2fba707c..865c96c06c 100644
--- a/src/ReactiveUI.AOTTests/ComprehensiveAOTMarkupTests.cs
+++ b/src/ReactiveUI.AOTTests/ComprehensiveAOTMarkupTests.cs
@@ -3,12 +3,9 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;
-using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using Splat;
 
 namespace ReactiveUI.AOTTests;
 
diff --git a/src/ReactiveUI.AOTTests/ComprehensiveAOTTests.cs b/src/ReactiveUI.AOTTests/ComprehensiveAOTTests.cs
index dcbf1cd87a..4f9b5d5fc6 100644
--- a/src/ReactiveUI.AOTTests/ComprehensiveAOTTests.cs
+++ b/src/ReactiveUI.AOTTests/ComprehensiveAOTTests.cs
@@ -3,12 +3,9 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;
-using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using Splat;
 
 namespace ReactiveUI.AOTTests;
 
diff --git a/src/ReactiveUI.AOTTests/FinalAOTValidationTests.cs b/src/ReactiveUI.AOTTests/FinalAOTValidationTests.cs
index 75edb583c1..97807fe9c6 100644
--- a/src/ReactiveUI.AOTTests/FinalAOTValidationTests.cs
+++ b/src/ReactiveUI.AOTTests/FinalAOTValidationTests.cs
@@ -3,13 +3,10 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using System.Reactive;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;
-using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using Splat;
 
 namespace ReactiveUI.AOTTests;
 
diff --git a/src/ReactiveUI.AOTTests/GlobalUsings.cs b/src/ReactiveUI.AOTTests/GlobalUsings.cs
index 716d007c1a..f235253daf 100644
--- a/src/ReactiveUI.AOTTests/GlobalUsings.cs
+++ b/src/ReactiveUI.AOTTests/GlobalUsings.cs
@@ -9,6 +9,6 @@
 global using global::System.Collections.Generic;
 global using global::System.Diagnostics.CodeAnalysis;
 global using global::System.Linq;
+global using global::System.Reactive.Disposables.Fluent;
 global using global::System.Reactive.Linq;
-global using global::System.Threading;
-global using global::System.Threading.Tasks;
\ No newline at end of file
+global using global::System.Threading.Tasks;
diff --git a/src/ReactiveUI.AOTTests/StringBasedObservationTests.cs b/src/ReactiveUI.AOTTests/StringBasedObservationTests.cs
index 606ba422af..0e39952558 100644
--- a/src/ReactiveUI.AOTTests/StringBasedObservationTests.cs
+++ b/src/ReactiveUI.AOTTests/StringBasedObservationTests.cs
@@ -3,10 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
-using System.Reactive.Concurrency;
-using System.Reactive.Linq;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>
diff --git a/src/ReactiveUI.AOTTests/StringBasedSemanticsTests.cs b/src/ReactiveUI.AOTTests/StringBasedSemanticsTests.cs
index 476e6e1baf..eb77afeb83 100644
--- a/src/ReactiveUI.AOTTests/StringBasedSemanticsTests.cs
+++ b/src/ReactiveUI.AOTTests/StringBasedSemanticsTests.cs
@@ -3,8 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Reactive.Linq;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>
diff --git a/src/ReactiveUI.AOTTests/TestReactiveObject.cs b/src/ReactiveUI.AOTTests/TestReactiveObject.cs
index b85155b479..50247cbe92 100644
--- a/src/ReactiveUI.AOTTests/TestReactiveObject.cs
+++ b/src/ReactiveUI.AOTTests/TestReactiveObject.cs
@@ -3,9 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
-using System.Reactive.Linq;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>
diff --git a/src/ReactiveUI.AOTTests/ViewLocatorAOTMappingTests.cs b/src/ReactiveUI.AOTTests/ViewLocatorAOTMappingTests.cs
index 174b1b5e92..6e4f3ff665 100644
--- a/src/ReactiveUI.AOTTests/ViewLocatorAOTMappingTests.cs
+++ b/src/ReactiveUI.AOTTests/ViewLocatorAOTMappingTests.cs
@@ -3,8 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Reactive.Linq;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>
diff --git a/src/ReactiveUI.Blazor/GlobalUsings.cs b/src/ReactiveUI.Blazor/GlobalUsings.cs
index c0e66f02bd..60b0425a4d 100644
--- a/src/ReactiveUI.Blazor/GlobalUsings.cs
+++ b/src/ReactiveUI.Blazor/GlobalUsings.cs
@@ -11,5 +11,6 @@
 global using global::System.Reactive;
 global using global::System.Reactive.Concurrency;
 global using global::System.Reactive.Disposables;
+global using global::System.Reactive.Disposables.Fluent;
 global using global::System.Reactive.Linq;
 global using global::System.Reactive.Subjects;
diff --git a/src/ReactiveUI.Builder.WpfApp/Views/ChatRoomView.xaml.cs b/src/ReactiveUI.Builder.WpfApp/Views/ChatRoomView.xaml.cs
index dd4b42d551..21d2f5e977 100644
--- a/src/ReactiveUI.Builder.WpfApp/Views/ChatRoomView.xaml.cs
+++ b/src/ReactiveUI.Builder.WpfApp/Views/ChatRoomView.xaml.cs
@@ -4,6 +4,7 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Reactive.Disposables;
+using System.Reactive.Disposables.Fluent;
 using System.Windows;
 using ReactiveUI.Builder.WpfApp.ViewModels;
 
diff --git a/src/ReactiveUI.Builder.WpfApp/Views/LobbyView.xaml.cs b/src/ReactiveUI.Builder.WpfApp/Views/LobbyView.xaml.cs
index c1af1208fe..a899070a3d 100644
--- a/src/ReactiveUI.Builder.WpfApp/Views/LobbyView.xaml.cs
+++ b/src/ReactiveUI.Builder.WpfApp/Views/LobbyView.xaml.cs
@@ -4,6 +4,7 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Reactive.Disposables;
+using System.Reactive.Disposables.Fluent;
 using System.Reactive.Linq;
 using System.Windows;
 using System.Windows.Input;
diff --git a/src/ReactiveUI.Maui/GlobalUsings.cs b/src/ReactiveUI.Maui/GlobalUsings.cs
index df413c9efa..502eb74165 100644
--- a/src/ReactiveUI.Maui/GlobalUsings.cs
+++ b/src/ReactiveUI.Maui/GlobalUsings.cs
@@ -10,6 +10,7 @@
 global using System.Reactive;
 global using System.Reactive.Concurrency;
 global using System.Reactive.Disposables;
+global using System.Reactive.Disposables.Fluent;
 global using System.Reactive.Linq;
 global using System.Reactive.Subjects;
 global using System.Threading.Tasks;
diff --git a/src/ReactiveUI/GlobalUsings.cs b/src/ReactiveUI/GlobalUsings.cs
index 910b59068c..ba0e64eb93 100644
--- a/src/ReactiveUI/GlobalUsings.cs
+++ b/src/ReactiveUI/GlobalUsings.cs
@@ -17,6 +17,7 @@
 global using global::System.Reactive;
 global using global::System.Reactive.Concurrency;
 global using global::System.Reactive.Disposables;
+global using global::System.Reactive.Disposables.Fluent;
 global using global::System.Reactive.Linq;
 global using global::System.Reactive.Subjects;
 global using global::System.Reactive.Threading.Tasks;
diff --git a/src/ReactiveUI/Mixins/DisposableMixins.cs b/src/ReactiveUI/Mixins/DisposableMixins.cs
deleted file mode 100644
index fe61cac7b3..0000000000
--- a/src/ReactiveUI/Mixins/DisposableMixins.cs
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright (c) 2025 .NET Foundation and Contributors. All rights reserved.
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for full license information.
-
-namespace System.Reactive.Disposables;
-
-/// <summary>
-/// Extension methods associated with the IDisposable interface.
-/// </summary>
-public static class DisposableMixins
-{
-    /// <summary>
-    /// Ensures the provided disposable is disposed with the specified <see cref="CompositeDisposable"/>.
-    /// </summary>
-    /// <typeparam name="T">
-    /// The type of the disposable.
-    /// </typeparam>
-    /// <param name="item">
-    /// The disposable we are going to want to be disposed by the CompositeDisposable.
-    /// </param>
-    /// <param name="compositeDisposable">
-    /// The <see cref="CompositeDisposable"/> to which <paramref name="item"/> will be added.
-    /// </param>
-    /// <returns>
-    /// The disposable.
-    /// </returns>
-    public static T DisposeWith<T>(this T item, CompositeDisposable compositeDisposable)
-        where T : IDisposable
-    {
-        compositeDisposable.ArgumentNullExceptionThrowIfNull(nameof(compositeDisposable));
-
-        compositeDisposable.Add(item);
-        return item;
-    }
-}