diff --git a/src/installer/pkg/sfx/Microsoft.NETCore.App/PackageOverrides.txt b/src/installer/pkg/sfx/Microsoft.NETCore.App/PackageOverrides.txt
index f49c727fc22b98..f06bb0137eee58 100644
--- a/src/installer/pkg/sfx/Microsoft.NETCore.App/PackageOverrides.txt
+++ b/src/installer/pkg/sfx/Microsoft.NETCore.App/PackageOverrides.txt
@@ -187,6 +187,7 @@ System.IO.Pipes|4.3.0
System.IO.Pipes.AccessControl|5.0.0
System.IO.UnmanagedMemoryStream|4.3.0
System.Linq|4.3.0
+System.Linq.AsyncEnumerable|${ProductVersion}
System.Linq.Expressions|4.3.0
System.Linq.Parallel|4.3.0
System.Linq.Queryable|4.3.0
diff --git a/src/libraries/NetCoreAppLibrary.props b/src/libraries/NetCoreAppLibrary.props
index a3f63978bf92da..8e94beeba018ee 100644
--- a/src/libraries/NetCoreAppLibrary.props
+++ b/src/libraries/NetCoreAppLibrary.props
@@ -80,6 +80,7 @@
System.IO.Pipelines;
System.IO.UnmanagedMemoryStream;
System.Linq;
+ System.Linq.AsyncEnumerable;
System.Linq.Expressions;
System.Linq.Parallel;
System.Linq.Queryable;
diff --git a/src/libraries/System.Linq.AsyncEnumerable/Directory.Build.props b/src/libraries/System.Linq.AsyncEnumerable/Directory.Build.props
new file mode 100644
index 00000000000000..e8d65546d0c807
--- /dev/null
+++ b/src/libraries/System.Linq.AsyncEnumerable/Directory.Build.props
@@ -0,0 +1,6 @@
+
+
+
+ Microsoft
+
+
diff --git a/src/libraries/System.Linq.AsyncEnumerable/README.md b/src/libraries/System.Linq.AsyncEnumerable/README.md
new file mode 100644
index 00000000000000..c13b9a796b18ce
--- /dev/null
+++ b/src/libraries/System.Linq.AsyncEnumerable/README.md
@@ -0,0 +1,18 @@
+# System.Linq.AsyncEnumerable
+
+Language-Integrated Query (LINQ) is the name for a set of technologies based on the integration of query capabilities directly into the C# language.
+
+Documentation can be found at https://learn.microsoft.com/dotnet/api/system.linq.
+
+This library provides an implementation of LINQ APIs for `IAsyncEnumerable`.
+
+## Contribution Bar
+
+- [x] [We consider new features, new APIs and performance changes](../../libraries/README.md#primary-bar)
+- [x] [We consider PRs that target this library for new source code analyzers](../../libraries/README.md#secondary-bars)
+
+See the [Help Wanted](https://github.com/dotnet/runtime/issues?q=is%3Aissue+is%3Aopen+label%3Aarea-System.Linq+label%3A%22help+wanted%22+) issues.
+
+## Deployment
+
+System.Linq.AsyncEnumerable is shipped as part of the .NET shared framework and as a NuGet package.
diff --git a/src/libraries/System.Linq.AsyncEnumerable/System.Linq.AsyncEnumerable.sln b/src/libraries/System.Linq.AsyncEnumerable/System.Linq.AsyncEnumerable.sln
new file mode 100644
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+++ b/src/libraries/System.Linq.AsyncEnumerable/System.Linq.AsyncEnumerable.sln
@@ -0,0 +1,149 @@
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diff --git a/src/libraries/System.Linq.AsyncEnumerable/ref/System.Linq.AsyncEnumerable.cs b/src/libraries/System.Linq.AsyncEnumerable/ref/System.Linq.AsyncEnumerable.cs
new file mode 100644
index 00000000000000..6153d0bd56a07c
--- /dev/null
+++ b/src/libraries/System.Linq.AsyncEnumerable/ref/System.Linq.AsyncEnumerable.cs
@@ -0,0 +1,202 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// ------------------------------------------------------------------------------
+// Changes to this file must follow the https://aka.ms/api-review process.
+// ------------------------------------------------------------------------------
+
+namespace System.Linq
+{
+ public static partial class AsyncEnumerable
+ {
+ public static System.Threading.Tasks.ValueTask AggregateAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Func> func, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AggregateAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Func func, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AggregateAsync(this System.Collections.Generic.IAsyncEnumerable source, TAccumulate seed, System.Func> func, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AggregateAsync(this System.Collections.Generic.IAsyncEnumerable source, TAccumulate seed, System.Func func, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AggregateAsync(this System.Collections.Generic.IAsyncEnumerable source, TAccumulate seed, System.Func> func, System.Func> resultSelector, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AggregateAsync(this System.Collections.Generic.IAsyncEnumerable source, TAccumulate seed, System.Func func, System.Func resultSelector, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Collections.Generic.IAsyncEnumerable> AggregateBy(this System.Collections.Generic.IAsyncEnumerable source, System.Func> keySelector, System.Func> seedSelector, System.Func> func, System.Collections.Generic.IEqualityComparer? keyComparer = null) where TKey : notnull { throw null; }
+ public static System.Collections.Generic.IAsyncEnumerable> AggregateBy(this System.Collections.Generic.IAsyncEnumerable source, System.Func> keySelector, TAccumulate seed, System.Func> func, System.Collections.Generic.IEqualityComparer? keyComparer = null) where TKey : notnull { throw null; }
+ public static System.Collections.Generic.IAsyncEnumerable> AggregateBy(this System.Collections.Generic.IAsyncEnumerable source, System.Func keySelector, System.Func seedSelector, System.Func func, System.Collections.Generic.IEqualityComparer? keyComparer = null) where TKey : notnull { throw null; }
+ public static System.Collections.Generic.IAsyncEnumerable> AggregateBy(this System.Collections.Generic.IAsyncEnumerable source, System.Func keySelector, TAccumulate seed, System.Func func, System.Collections.Generic.IEqualityComparer? keyComparer = null) where TKey : notnull { throw null; }
+ public static System.Threading.Tasks.ValueTask AllAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Func predicate, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AllAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Func> predicate, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AnyAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Func predicate, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AnyAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Func> predicate, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AnyAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Collections.Generic.IAsyncEnumerable Append(this System.Collections.Generic.IAsyncEnumerable source, TSource element) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Threading.Tasks.ValueTask AverageAsync(this System.Collections.Generic.IAsyncEnumerable source, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+ public static System.Collections.Generic.IAsyncEnumerable Cast(this System.Collections.Generic.IAsyncEnumerable