diff --git a/Directory.Packages.props b/Directory.Packages.props
index 1a83625bdc29..a44ed722182f 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -55,6 +55,7 @@
     <PackageVersion Include="Microsoft.DotNet.SignCheck" Version="$(ArcadeSdkVersion)" />
     <PackageVersion Include="Microsoft.DotNet.XUnitExtensions" Version="$(MicrosoftDotNetXUnitExtensionsVersion)" />
     <PackageVersion Include="Microsoft.Extensions.DependencyModel" Version="$(MicrosoftExtensionsDependencyModelPackageVersion)" />
+    <PackageVersion Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="$(MicrosoftExtensionsDependencyInjectionAbstractionsPackageVersion)" />
     <PackageVersion Include="Microsoft.Extensions.FileProviders.Abstractions" Version="$(MicrosoftExtensionsFileProvidersAbstractionsPackageVersion)" />
     <PackageVersion Include="Microsoft.Extensions.FileSystemGlobbing" Version="$(MicrosoftExtensionsFileSystemGlobbingPackageVersion)" />
     <PackageVersion Include="Microsoft.Extensions.Logging" Version="$(MicrosoftExtensionsLoggingVersion)" />
diff --git a/eng/Version.Details.props b/eng/Version.Details.props
index c88cd20c8ed9..d6708ed330ab 100644
--- a/eng/Version.Details.props
+++ b/eng/Version.Details.props
@@ -101,6 +101,7 @@ This file should be imported by eng/Versions.props
     <MicrosoftDotnetWpfProjectTemplatesPackageVersion>10.0.0-rtm.25523.111</MicrosoftDotnetWpfProjectTemplatesPackageVersion>
     <MicrosoftExtensionsConfigurationIniPackageVersion>10.0.1</MicrosoftExtensionsConfigurationIniPackageVersion>
     <MicrosoftExtensionsDependencyModelPackageVersion>10.0.1</MicrosoftExtensionsDependencyModelPackageVersion>
+    <MicrosoftExtensionsDependencyInjectionAbstractionsPackageVersion>10.0.1</MicrosoftExtensionsDependencyInjectionAbstractionsPackageVersion>
     <MicrosoftExtensionsFileProvidersAbstractionsPackageVersion>10.0.1</MicrosoftExtensionsFileProvidersAbstractionsPackageVersion>
     <MicrosoftExtensionsFileProvidersEmbeddedPackageVersion>10.0.1</MicrosoftExtensionsFileProvidersEmbeddedPackageVersion>
     <MicrosoftExtensionsFileSystemGlobbingPackageVersion>10.0.1</MicrosoftExtensionsFileSystemGlobbingPackageVersion>
diff --git a/eng/Version.Details.xml b/eng/Version.Details.xml
index e8d4d98820b8..cde5e4dcbb9c 100644
--- a/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@ -440,6 +440,11 @@
       <Sha>fad253f51b461736dfd3cd9c15977bb7493becef</Sha>
     </Dependency>
     <!-- Dependency required for flowing correct package version in source-build, using PVP flow. -->
+    <Dependency Name="Microsoft.Extensions.DependencyInjection.Abstractions" Version="10.0.1">
+      <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-dotnet</Uri>
+      <Sha>fad253f51b461736dfd3cd9c15977bb7493becef</Sha>
+    </Dependency>
+    <!-- Dependency required for flowing correct package version in source-build, using PVP flow. -->
     <Dependency Name="Microsoft.Extensions.Logging.Console" Version="10.0.1">
       <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-dotnet</Uri>
       <Sha>fad253f51b461736dfd3cd9c15977bb7493becef</Sha>
diff --git a/eng/Versions.props b/eng/Versions.props
index 705bbfc33b22..051cd561557f 100644
--- a/eng/Versions.props
+++ b/eng/Versions.props
@@ -80,6 +80,7 @@
     <MicrosoftBclAsyncInterfacesToolsetPackageVersion>9.0.0</MicrosoftBclAsyncInterfacesToolsetPackageVersion>
     <MicrosoftDeploymentDotNetReleasesToolsetPackageVersion>2.0.0-preview.1.24427.4</MicrosoftDeploymentDotNetReleasesToolsetPackageVersion>
     <MicrosoftExtensionsLoggingAbstractionsToolsetPackageVersion>9.0.0</MicrosoftExtensionsLoggingAbstractionsToolsetPackageVersion>
+    <MicrosoftExtensionsDependencyInjectionAbstractionsToolsetPackageVersion>9.0.0</MicrosoftExtensionsDependencyInjectionAbstractionsToolsetPackageVersion>
     <SystemBuffersToolsetPackageVersion>4.5.1</SystemBuffersToolsetPackageVersion>
     <SystemCollectionsImmutableToolsetPackageVersion>9.0.0</SystemCollectionsImmutableToolsetPackageVersion>
     <SystemMemoryToolsetPackageVersion>4.5.5</SystemMemoryToolsetPackageVersion>
@@ -142,7 +143,7 @@
   </PropertyGroup>
   <PropertyGroup Label="Workload manifest package versions">
     <MauiFeatureBand>10.0.100</MauiFeatureBand>
-    
+
     <!--
       Updates to any of these versions will require the updating of that package version in the
       source-build-reference-packages repo as a text-only package.
diff --git a/src/BuiltInTools/HotReloadClient/Microsoft.DotNet.HotReload.Client.Package.csproj b/src/BuiltInTools/HotReloadClient/Microsoft.DotNet.HotReload.Client.Package.csproj
index 7996da1c7dbe..93b35d8e4956 100644
--- a/src/BuiltInTools/HotReloadClient/Microsoft.DotNet.HotReload.Client.Package.csproj
+++ b/src/BuiltInTools/HotReloadClient/Microsoft.DotNet.HotReload.Client.Package.csproj
@@ -39,6 +39,7 @@
     <PackageReference Include="System.Text.Json" VersionOverride="$(SystemTextJsonToolsetPackageVersion)" />
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" VersionOverride="$(MicrosoftBclAsyncInterfacesToolsetPackageVersion)" />
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" VersionOverride="$(MicrosoftExtensionsLoggingAbstractionsToolsetPackageVersion)" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" VersionOverride="$(MicrosoftExtensionsDependencyInjectionAbstractionsToolsetPackageVersion)" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp'">
diff --git a/src/BuiltInTools/Watch/Build/FileItem.cs b/src/BuiltInTools/Watch/Build/FileItem.cs
index bd6719f2ca00..3d3c4fd6ffb2 100644
--- a/src/BuiltInTools/Watch/Build/FileItem.cs
+++ b/src/BuiltInTools/Watch/Build/FileItem.cs
@@ -1,7 +1,6 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 namespace Microsoft.DotNet.Watch
 {
     internal readonly record struct FileItem
diff --git a/src/BuiltInTools/Watch/Build/ProjectGraphFactory.cs b/src/BuiltInTools/Watch/Build/ProjectGraphFactory.cs
index 520bd4b8f972..56ffe6560b0e 100644
--- a/src/BuiltInTools/Watch/Build/ProjectGraphFactory.cs
+++ b/src/BuiltInTools/Watch/Build/ProjectGraphFactory.cs
@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections.Immutable;
@@ -29,7 +29,7 @@ internal sealed class ProjectGraphFactory(ImmutableDictionary<string, string> gl
         reuseProjectRootElementCache: true);
 
     /// <summary>
-    /// Tries to create a project graph by running the build evaluation phase on the <see cref="rootProjectFile"/>.
+    /// Tries to create a project graph by running the build evaluation phase on the <paramref name="rootProjectFile"/>.
     /// </summary>
     public ProjectGraph? TryLoadProjectGraph(
         string rootProjectFile,
diff --git a/src/BuiltInTools/Watch/Build/ProjectNodeMap.cs b/src/BuiltInTools/Watch/Build/ProjectNodeMap.cs
index a916346da9cc..69e2e5a0440b 100644
--- a/src/BuiltInTools/Watch/Build/ProjectNodeMap.cs
+++ b/src/BuiltInTools/Watch/Build/ProjectNodeMap.cs
@@ -1,7 +1,6 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 using Microsoft.Build.Graph;
 using Microsoft.Extensions.Logging;
 
diff --git a/src/BuiltInTools/Watch/Context/DotNetWatchContext.cs b/src/BuiltInTools/Watch/Context/DotNetWatchContext.cs
index 591b6e283302..f7caada6824c 100644
--- a/src/BuiltInTools/Watch/Context/DotNetWatchContext.cs
+++ b/src/BuiltInTools/Watch/Context/DotNetWatchContext.cs
@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 using Microsoft.Extensions.Logging;
 
 namespace Microsoft.DotNet.Watch
diff --git a/src/BuiltInTools/Watch/FileWatcher/FileWatcher.cs b/src/BuiltInTools/Watch/FileWatcher/FileWatcher.cs
index 3f5bff195e92..1e445f5e9cb9 100644
--- a/src/BuiltInTools/Watch/FileWatcher/FileWatcher.cs
+++ b/src/BuiltInTools/Watch/FileWatcher/FileWatcher.cs
@@ -74,7 +74,7 @@ private void Watch(IEnumerable<string> filePaths, bool containingDirectories, bo
                 from path in filePaths
                 group path by PathUtilities.EnsureTrailingSlash(PathUtilities.NormalizeDirectorySeparators(Path.GetDirectoryName(path)!))
                 into g
-                select (g.Key, containingDirectories ? [] : g.Select(path => Path.GetFileName(path)).ToImmutableHashSet(PathUtilities.OSSpecificPathComparer));
+                select (g.Key, containingDirectories ? [] : g.Select(Path.GetFileName).ToImmutableHashSet(PathUtilities.OSSpecificPathComparer));
 
             foreach (var (directory, fileNames) in filesByDirectory)
             {
diff --git a/src/BuiltInTools/Watch/FileWatcher/PollingDirectoryWatcher.cs b/src/BuiltInTools/Watch/FileWatcher/PollingDirectoryWatcher.cs
index 143881c65f7e..89a77475aa77 100644
--- a/src/BuiltInTools/Watch/FileWatcher/PollingDirectoryWatcher.cs
+++ b/src/BuiltInTools/Watch/FileWatcher/PollingDirectoryWatcher.cs
@@ -19,7 +19,7 @@ internal sealed class PollingDirectoryWatcher : DirectoryWatcher
         private Dictionary<string, DateTime> _snapshotBuilder = new(PathUtilities.OSSpecificPathComparer);
         private readonly Dictionary<string, ChangeKind> _changesBuilder = new(PathUtilities.OSSpecificPathComparer);
 
-        private Thread _pollingThread;
+        private readonly Thread _pollingThread;
         private bool _raiseEvents;
 
         private volatile bool _disposed;
@@ -88,10 +88,7 @@ private void CaptureInitialSnapshot()
         {
             Debug.Assert(_currentSnapshot.Count == 0);
 
-            ForeachEntityInDirectory(_watchedDirectory, (filePath, writeTime) =>
-            {
-                _currentSnapshot.Add(filePath, writeTime);
-            });
+            ForeachEntityInDirectory(_watchedDirectory, _currentSnapshot.Add);
         }
 
         private void CheckForChangedFiles()
diff --git a/src/BuiltInTools/Watch/HotReload/CompilationHandler.cs b/src/BuiltInTools/Watch/HotReload/CompilationHandler.cs
index 80e2b5169735..360d49ebf8ae 100644
--- a/src/BuiltInTools/Watch/HotReload/CompilationHandler.cs
+++ b/src/BuiltInTools/Watch/HotReload/CompilationHandler.cs
@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections.Immutable;
@@ -23,7 +23,6 @@ internal sealed class CompilationHandler : IDisposable
         /// Lock to synchronize:
         /// <see cref="_runningProjects"/>
         /// <see cref="_previousUpdates"/>
-        /// <see cref="_currentAggregateCapabilities"/>
         /// </summary>
         private readonly object _runningProjectsAndUpdatesGuard = new();
 
@@ -584,7 +583,7 @@ static MessageDescriptor GetMessageDescriptor(Diagnostic diagnostic, bool verbos
         private static readonly string[] s_targets = [TargetNames.GenerateComputedBuildStaticWebAssets, TargetNames.ResolveReferencedProjectsStaticWebAssets];
 
         private static bool HasScopedCssTargets(ProjectInstance projectInstance)
-            => s_targets.All(t => projectInstance.Targets.ContainsKey(t));
+            => s_targets.All(projectInstance.Targets.ContainsKey);
 
         public async ValueTask HandleStaticAssetChangesAsync(
             IReadOnlyList<ChangedFile> files,
diff --git a/src/BuiltInTools/Watch/HotReload/HotReloadDotNetWatcher.cs b/src/BuiltInTools/Watch/HotReload/HotReloadDotNetWatcher.cs
index e82c41ed0f09..93cde1a44a06 100644
--- a/src/BuiltInTools/Watch/HotReload/HotReloadDotNetWatcher.cs
+++ b/src/BuiltInTools/Watch/HotReload/HotReloadDotNetWatcher.cs
@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections.Immutable;
@@ -145,7 +145,7 @@ public async Task WatchAsync(CancellationToken shutdownCancellationToken)
                     }
 
                     // Cancel iteration as soon as the root process exits, so that we don't spent time loading solution, etc. when the process is already dead.
-                    rootRunningProject.ProcessExitedCancellationToken.Register(() => iterationCancellationSource.Cancel());
+                    rootRunningProject.ProcessExitedCancellationToken.Register(iterationCancellationSource.Cancel);
 
                     if (shutdownCancellationToken.IsCancellationRequested)
                     {
@@ -474,7 +474,7 @@ async Task<ImmutableArray<ChangedFile>> CaptureChangedFilesSnapshot(ImmutableArr
 
                                 foreach (var file in changedFiles)
                                 {
-                                    if (file.Item.ContainingProjectPaths.All(containingProjectPath => rebuiltProjectPaths.Contains(containingProjectPath)))
+                                    if (file.Item.ContainingProjectPaths.All(rebuiltProjectPaths.Contains))
                                     {
                                         newChangedFiles.Add(file);
                                     }
@@ -736,7 +736,7 @@ private async ValueTask WaitForFileChangeBeforeRestarting(FileWatcher fileWatche
                 fileWatcher.WatchContainingDirectories([_context.RootProjectOptions.ProjectPath], includeSubdirectories: true);
 
                 _ = await fileWatcher.WaitForFileChangeAsync(
-                    acceptChange: change => AcceptChange(change),
+                    acceptChange: AcceptChange,
                     startedWatching: () => _context.Logger.Log(MessageDescriptor.WaitingForFileChangeBeforeRestarting),
                     cancellationToken);
             }
diff --git a/src/BuiltInTools/Watch/HotReload/HotReloadEventSource.cs b/src/BuiltInTools/Watch/HotReload/HotReloadEventSource.cs
index 5fb26269ae33..4196f85ba21b 100644
--- a/src/BuiltInTools/Watch/HotReload/HotReloadEventSource.cs
+++ b/src/BuiltInTools/Watch/HotReload/HotReloadEventSource.cs
@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 using System.Diagnostics.Tracing;
 
 namespace Microsoft.DotNet.Watch
diff --git a/src/BuiltInTools/Watch/Microsoft.DotNet.HotReload.Watch.csproj b/src/BuiltInTools/Watch/Microsoft.DotNet.HotReload.Watch.csproj
index aa3590c0c328..f3a2874dd3ea 100644
--- a/src/BuiltInTools/Watch/Microsoft.DotNet.HotReload.Watch.csproj
+++ b/src/BuiltInTools/Watch/Microsoft.DotNet.HotReload.Watch.csproj
@@ -16,7 +16,7 @@
       Disable CS9057 in source-only dev/ci builds. This is necessary because dotnet-watch distributes some ASP.NET Core
       analyzers. These analyzers get built with a dependency on the live version of Microsoft.CodeAnalysis. In a dev/ci
       build, the assembly version associated with Microsoft.CodeAnalysis in that case is 42.42.42.4242, set by Arcade in
-      dev/ci builds. So when building dotnet-watch with its analyzer dependencies, it will cause CS9057 because the 
+      dev/ci builds. So when building dotnet-watch with its analyzer dependencies, it will cause CS9057 because the
       analyzer assembly version is not the same as the compiler assembly version being used by the sdk that the project
       is being built with. But this is fine because the analyzer is just being used here to distribute it with the tool.
     -->
diff --git a/src/BuiltInTools/Watch/Process/ProcessRunner.cs b/src/BuiltInTools/Watch/Process/ProcessRunner.cs
index 4734b844fdce..2cfba7ade091 100644
--- a/src/BuiltInTools/Watch/Process/ProcessRunner.cs
+++ b/src/BuiltInTools/Watch/Process/ProcessRunner.cs
@@ -1,7 +1,6 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 using System.Diagnostics;
 using Microsoft.Extensions.Logging;
 
diff --git a/src/BuiltInTools/Watch/Process/ProcessSpec.cs b/src/BuiltInTools/Watch/Process/ProcessSpec.cs
index b3e1eaa1a6a6..15e4f1a12eb1 100644
--- a/src/BuiltInTools/Watch/Process/ProcessSpec.cs
+++ b/src/BuiltInTools/Watch/Process/ProcessSpec.cs
@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 namespace Microsoft.DotNet.Watch
 {
     internal sealed class ProcessSpec
@@ -14,10 +13,10 @@ internal sealed class ProcessSpec
         public Action<OutputLine>? OnOutput { get; set; }
         public ProcessExitAction? OnExit { get; set; }
         public CancellationToken CancelOutputCapture { get; set; }
-        public bool UseShellExecute { get; set; } = false;
+        public bool UseShellExecute { get; set; }
 
         /// <summary>
-        /// True if the process is a user application, false if it is a helper process (e.g. dotnet build).</param>
+        /// True if the process is a user application, false if it is a helper process (e.g. dotnet build).
         /// </summary>
         public bool IsUserApplication { get; set; }
 
diff --git a/src/BuiltInTools/Watch/Process/RunningProject.cs b/src/BuiltInTools/Watch/Process/RunningProject.cs
index d94c90fbf6e5..c4d63e953a22 100644
--- a/src/BuiltInTools/Watch/Process/RunningProject.cs
+++ b/src/BuiltInTools/Watch/Process/RunningProject.cs
@@ -1,7 +1,6 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-
 using System.Collections.Immutable;
 using System.Diagnostics;
 using Microsoft.Build.Graph;
diff --git a/src/BuiltInTools/Watch/Utilities/PathUtilities.cs b/src/BuiltInTools/Watch/Utilities/PathUtilities.cs
index e7f21ea13ac6..d8395337dc8a 100644
--- a/src/BuiltInTools/Watch/Utilities/PathUtilities.cs
+++ b/src/BuiltInTools/Watch/Utilities/PathUtilities.cs
@@ -5,7 +5,7 @@ namespace Microsoft.DotNet.Watch;
 
 internal static class PathUtilities
 {
-    public static readonly IEqualityComparer<string> OSSpecificPathComparer = Path.DirectorySeparatorChar == '\\' ? StringComparer.OrdinalIgnoreCase : StringComparer.Ordinal;
+    public static readonly IEqualityComparer<string?> OSSpecificPathComparer = Path.DirectorySeparatorChar == '\\' ? StringComparer.OrdinalIgnoreCase : StringComparer.Ordinal;
     public static readonly StringComparison OSSpecificPathComparison = Path.DirectorySeparatorChar == '\\' ? StringComparison.OrdinalIgnoreCase : StringComparison.Ordinal;
 
     public static string ExecutableExtension
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/FileLevelDirectiveHelpers.cs b/src/Cli/Microsoft.DotNet.FileBasedPrograms/FileLevelDirectiveHelpers.cs
index 8457183e2cba..681843c6cbc8 100644
--- a/src/Cli/Microsoft.DotNet.FileBasedPrograms/FileLevelDirectiveHelpers.cs
+++ b/src/Cli/Microsoft.DotNet.FileBasedPrograms/FileLevelDirectiveHelpers.cs
@@ -159,9 +159,8 @@ public static void FindLeadingDirectives(
                 if (CSharpDirective.Parse(context) is { } directive)
                 {
                     // If the directive is already present, report an error.
-                    if (deduplicated.ContainsKey(directive))
+                    if (deduplicated.TryGetValue(directive, out var existingDirective))
                     {
-                        var existingDirective = deduplicated[directive];
                         var typeAndName = $"#:{existingDirective.GetType().Name.ToLowerInvariant()} {existingDirective.Name}";
                         reportError(sourceFile, directive.Info.Span, string.Format(FileBasedProgramsResources.DuplicateDirective, typeAndName));
                     }
diff --git a/src/Microsoft.DotNet.ProjectTools/LaunchSettings/LaunchSettings.cs b/src/Microsoft.DotNet.ProjectTools/LaunchSettings/LaunchSettings.cs
index 5e22df2e18d7..ae1c60161b27 100644
--- a/src/Microsoft.DotNet.ProjectTools/LaunchSettings/LaunchSettings.cs
+++ b/src/Microsoft.DotNet.ProjectTools/LaunchSettings/LaunchSettings.cs
@@ -20,7 +20,6 @@ public static class LaunchSettings
 
     public static IEnumerable<string> SupportedProfileTypes => s_providers.Keys;
 
-
     public static string GetPropertiesLaunchSettingsPath(string directoryPath, string propertiesDirectoryName)
         => Path.Combine(directoryPath, propertiesDirectoryName, "launchSettings.json");