Merge remote-tracking branch 'origin/master' into copilot/add-performance-benchmarking

# Conflicts:
#	tests/SharpCompress.Performance/packages.lock.json

.editorconfig

@@ -368,6 +368,9 @@ dotnet_diagnostic.NX0001.severity = error
 dotnet_diagnostic.NX0002.severity = silent
 dotnet_diagnostic.NX0003.severity = silent
 
+dotnet_diagnostic.VSTHRD110.severity = error
+dotnet_diagnostic.VSTHRD107.severity = error
+
 ##########################################
 # Styles
 ##########################################

.gitignore

@@ -20,3 +20,7 @@ artifacts/
 
 .DS_Store
 *.snupkg
+
+# BenchmarkDotNet artifacts
+BenchmarkDotNet.Artifacts/
+**/BenchmarkDotNet.Artifacts/

AGENTS.md

@@ -14,6 +14,7 @@ SharpCompress is a pure C# compression library supporting multiple archive forma
 - Follow the existing code style and patterns in the codebase.
 
 ## General Instructions
+- **Agents should NEVER commit to git** - Agents should stage files and leave committing to the user. Only create commits when the user explicitly requests them.
 - Make only high confidence suggestions when reviewing code changes.
 - Write code with good maintainability practices, including comments on why certain design decisions were made.
 - Handle edge cases and write clear exception handling.
@@ -110,7 +111,7 @@ SharpCompress supports multiple archive and compression formats:
 - **Archive Formats**: Zip, Tar, 7Zip, Rar (read-only)
 - **Compression**: DEFLATE, BZip2, LZMA/LZMA2, PPMd, ZStandard (decompress only), Deflate64 (decompress only)
 - **Combined Formats**: Tar.GZip, Tar.BZip2, Tar.LZip, Tar.XZ, Tar.ZStandard
-- See FORMATS.md for complete format support matrix
+- See [docs/FORMATS.md](docs/FORMATS.md) for complete format support matrix
 
 ### Stream Handling Rules
 - **Disposal**: As of version 0.21, SharpCompress closes wrapped streams by default

Directory.Packages.props

@@ -1,5 +1,6 @@
 <Project>
   <ItemGroup>
+    <PackageVersion Include="BenchmarkDotNet" Version="0.14.0" />
     <PackageVersion Include="Bullseye" Version="6.1.0" />
     <PackageVersion Include="AwesomeAssertions" Version="9.3.0" />
     <PackageVersion Include="Glob" Version="1.1.9" />
@@ -13,8 +14,11 @@
     <PackageVersion Include="System.Memory" Version="4.6.3" />
     <PackageVersion Include="xunit" Version="2.9.3" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.5" />
-    <PackageVersion Include="Microsoft.NET.ILLink.Tasks" Version="10.0.0" />
-    <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
-    <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.3" />
+    <GlobalPackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
+    <GlobalPackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.3" />
+    <GlobalPackageReference
+      Include="Microsoft.VisualStudio.Threading.Analyzers"
+      Version="17.14.15"
+    />
   </ItemGroup>
 </Project>

README.md

@@ -4,7 +4,7 @@ SharpCompress is a compression library in pure C# for .NET Framework 4.8, .NET 8
 
 The major feature is support for non-seekable streams so large files can be processed on the fly (i.e. download stream).
 
-**NEW:** All I/O operations now support async/await for improved performance and scalability. See the [Async Usage](#async-usage) section below.
+**NEW:** All I/O operations now support async/await for improved performance and scalability. See the [USAGE.md](docs/USAGE.md#async-examples) for examples.
 
 GitHub Actions Build -
 [![SharpCompress](https://github.com/adamhathcock/sharpcompress/actions/workflows/dotnetcore.yml/badge.svg)](https://github.com/adamhathcock/sharpcompress/actions/workflows/dotnetcore.yml)
@@ -14,7 +14,7 @@ GitHub Actions Build -
 
 Post Issues on Github!
 
-Check the [Supported Formats](FORMATS.md) and [Basic Usage.](USAGE.md)
+Check the [Supported Formats](docs/FORMATS.md) and [Basic Usage.](docs/USAGE.md)
 
 ## Recommended Formats
 
@@ -34,235 +34,11 @@ Hi everyone. I hope you're using SharpCompress and finding it useful. Please giv
 
 Please do not email me directly to ask for help. If you think there is a real issue, please report it here.
 
-## Async Usage
-
-SharpCompress now provides full async/await support for all I/O operations, allowing for better performance and scalability in modern applications.
-
-### Async Reading Examples
-
-Extract entries asynchronously:
-```csharp
-using (Stream stream = File.OpenRead("archive.zip"))
-using (var reader = ReaderFactory.Open(stream))
-{
-    while (reader.MoveToNextEntry())
-    {
-        if (!reader.Entry.IsDirectory)
-        {
-            // Async extraction
-            await reader.WriteEntryToDirectoryAsync(
-                @"C:\temp",
-                new ExtractionOptions() { ExtractFullPath = true, Overwrite = true },
-                cancellationToken
-            );
-        }
-    }
-}
-```
-
-Extract all entries to directory asynchronously:
-```csharp
-using (Stream stream = File.OpenRead("archive.tar.gz"))
-using (var reader = ReaderFactory.Open(stream))
-{
-    await reader.WriteAllToDirectoryAsync(
-        @"C:\temp",
-        new ExtractionOptions() { ExtractFullPath = true, Overwrite = true },
-        cancellationToken
-    );
-}
-```
-
-Open entry stream asynchronously:
-```csharp
-using (var archive = ZipArchive.Open("archive.zip"))
-{
-    foreach (var entry in archive.Entries.Where(e => !e.IsDirectory))
-    {
-        using (var entryStream = await entry.OpenEntryStreamAsync(cancellationToken))
-        {
-            // Process stream asynchronously
-            await entryStream.CopyToAsync(outputStream, cancellationToken);
-        }
-    }
-}
-```
-
-### Async Writing Examples
-
-Write files asynchronously:
-```csharp
-using (Stream stream = File.OpenWrite("output.zip"))
-using (var writer = WriterFactory.Open(stream, ArchiveType.Zip, CompressionType.Deflate))
-{
-    await writer.WriteAsync("file1.txt", fileStream, DateTime.Now, cancellationToken);
-}
-```
-
-Write all files from directory asynchronously:
-```csharp
-using (Stream stream = File.OpenWrite("output.tar.gz"))
-using (var writer = WriterFactory.Open(stream, ArchiveType.Tar, new WriterOptions(CompressionType.GZip)))
-{
-    await writer.WriteAllAsync(@"D:\files", "*", SearchOption.AllDirectories, cancellationToken);
-}
-```
-
-All async methods support `CancellationToken` for graceful cancellation of long-running operations.
-
 ## Want to contribute?
 
 I'm always looking for help or ideas. Please submit code or email with ideas. Unfortunately, just letting me know you'd like to help is not enough because I really have no overall plan of what needs to be done. I'll definitely accept code submissions and add you as a member of the project!
 
-## TODOs (always lots)
-
-* RAR 5 decryption crc check support
-* 7Zip writing
-* Zip64 (Need writing and extend Reading)
-* Multi-volume Zip support.
-* ZStandard writing
-
-## Version Log
-
-* [Releases](https://github.com/adamhathcock/sharpcompress/releases)
-
-### Version 0.18
-
-* [Now on Github releases](https://github.com/adamhathcock/sharpcompress/releases/tag/0.18)
-
-### Version 0.17.1
-
-* Fix - [Bug Fix for .NET Core on Windows](https://github.com/adamhathcock/sharpcompress/pull/257)
-
-### Version 0.17.0
-
-* New - Full LZip support! Can read and write LZip files and Tars inside LZip files. [Make LZip a first class citizen. #241](https://github.com/adamhathcock/sharpcompress/issues/241)
-* New - XZ read support! Can read XZ files and Tars inside XZ files. [XZ in SharpCompress #91](https://github.com/adamhathcock/sharpcompress/issues/94)
-* Fix - [Regression - zip file writing on seekable streams always assumed stream start was 0. Introduced with Zip64 writing.](https://github.com/adamhathcock/sharpcompress/issues/244)
-* Fix - [Zip files with post-data descriptors can be properly skipped via decompression](https://github.com/adamhathcock/sharpcompress/issues/162)
-
-### Version 0.16.2
-
-* Fix [.NET 3.5 should support files and cryptography (was a regression from 0.16.0)](https://github.com/adamhathcock/sharpcompress/pull/251)
-* Fix [Zip per entry compression customization wrote the wrong method into the zip archive](https://github.com/adamhathcock/sharpcompress/pull/249)
-
-### Version 0.16.1
-
-* Fix [Preserve compression method when getting a compressed stream](https://github.com/adamhathcock/sharpcompress/pull/235)
-* Fix [RAR entry key normalization fix](https://github.com/adamhathcock/sharpcompress/issues/201)
-
-### Version 0.16.0
-
-* Breaking - [Progress Event Tracking rethink](https://github.com/adamhathcock/sharpcompress/pull/226)
-* Update to VS2017 - [VS2017](https://github.com/adamhathcock/sharpcompress/pull/231) - Framework targets have been changed.
-* New - [Add Zip64 writing](https://github.com/adamhathcock/sharpcompress/pull/211)
-* [Fix invalid/mismatching Zip version flags.](https://github.com/adamhathcock/sharpcompress/issues/164) - This allows nuget/System.IO.Packaging to read zip files generated by SharpCompress
-* [Fix 7Zip directory hiding](https://github.com/adamhathcock/sharpcompress/pull/215/files)
-* [Verify RAR CRC headers](https://github.com/adamhathcock/sharpcompress/pull/220)
-
-### Version 0.15.2
-
-* [Fix invalid headers](https://github.com/adamhathcock/sharpcompress/pull/210) - fixes an issue creating large-ish zip archives that was introduced with zip64 reading.
-
-### Version 0.15.1
-
-* [Zip64 extending information and ZipReader](https://github.com/adamhathcock/sharpcompress/pull/206)
-
-### Version 0.15.0
-
-* [Add zip64 support for ZipArchive extraction](https://github.com/adamhathcock/sharpcompress/pull/205)
-
-### Version 0.14.1
-
-* [.NET Assemblies aren't strong named](https://github.com/adamhathcock/sharpcompress/issues/158)
-* [Pkware encryption for Zip files didn't allow for multiple reads of an entry](https://github.com/adamhathcock/sharpcompress/issues/197)
-* [GZip Entry couldn't be read multiple times](https://github.com/adamhathcock/sharpcompress/issues/198)
-
-### Version 0.14.0
-
-* [Support for LZip reading in for Tars](https://github.com/adamhathcock/sharpcompress/pull/191)
-
-### Version 0.13.1
-
-* [Fix null password on ReaderFactory. Fix null options on SevenZipArchive](https://github.com/adamhathcock/sharpcompress/pull/188)
-* [Make PpmdProperties lazy to avoid unnecessary allocations.](https://github.com/adamhathcock/sharpcompress/pull/185)
-
-### Version 0.13.0
-
-* Breaking change: Big refactor of Options on API.
-* 7Zip supports Deflate
-
-### Version 0.12.4
-
-* Forward only zip issue fix https://github.com/adamhathcock/sharpcompress/issues/160
-* Try to fix frameworks again by copying targets from JSON.NET
-
-### Version 0.12.3
-
-* 7Zip fixes https://github.com/adamhathcock/sharpcompress/issues/73
-* Maybe all profiles will work with project.json now
-
-### Version 0.12.2
-
-* Support Profile 259 again
-
-### Version 0.12.1
-
-* Support Silverlight 5
-
-### Version 0.12.0
-
-* .NET Core RTM!
-* Bug fix for Tar long paths
-
-### Version 0.11.6
-
-* Bug fix for global header in Tar
-* Writers now have a leaveOpen `bool` overload. They won't close streams if not-requested to.
-
-### Version 0.11.5
-
-* Bug fix in Skip method
-
-### Version 0.11.4
-
-* SharpCompress is now endian neutral (matters for Mono platforms)
-* Fix for Inflate (need to change implementation)
-* Fixes for RAR detection
-
-### Version 0.11.1
-
-* Added Cancel on IReader
-* Removed .NET 2.0 support and LinqBridge dependency
-
-### Version 0.11
-
-* Been over a year, contains mainly fixes from contributors!
-* Possible breaking change: ArchiveEncoding is UTF8 by default now.
-* TAR supports writing long names using longlink
-* RAR Protect Header added
-
-### Version 0.10.3
-
-* Finally fixed Disposal issue when creating a new archive with the Archive API
-
-### Version 0.10.2
-
-* Fixed Rar Header reading for invalid extended time headers.
-* Windows Store assembly is now strong named
-* Known issues with Long Tar names being worked on
-* Updated to VS2013
-* Portable targets SL5 and Windows Phone 8 (up from SL4 and WP7)
-
-### Version 0.10.1
-
-* Fixed 7Zip extraction performance problem
-
-### Version 0.10:
-
-* Added support for RAR Decryption (thanks to https://github.com/hrasyid)
-* Embedded some BouncyCastle crypto classes to allow RAR Decryption and Winzip AES Decryption in Portable and Windows Store DLLs
-* Built in Release (I think)
+## Notes
 
 XZ implementation based on: https://github.com/sambott/XZ.NET by @sambott
 

build/packages.lock.json

@@ -14,11 +14,51 @@
         "resolved": "1.1.9",
         "contentHash": "AfK5+ECWYTP7G3AAdnU8IfVj+QpGjrh9GC2mpdcJzCvtQ4pnerAGwHsxJ9D4/RnhDUz2DSzd951O/lQjQby2Sw=="
       },
+      "Microsoft.NETFramework.ReferenceAssemblies": {
+        "type": "Direct",
+        "requested": "[1.0.3, )",
+        "resolved": "1.0.3",
+        "contentHash": "vUc9Npcs14QsyOD01tnv/m8sQUnGTGOw1BCmKcv77LBJY7OxhJ+zJF7UD/sCL3lYNFuqmQEVlkfS4Quif6FyYg==",
+        "dependencies": {
+          "Microsoft.NETFramework.ReferenceAssemblies.net461": "1.0.3"
+        }
+      },
+      "Microsoft.SourceLink.GitHub": {
+        "type": "Direct",
+        "requested": "[8.0.0, )",
+        "resolved": "8.0.0",
+        "contentHash": "G5q7OqtwIyGTkeIOAc3u2ZuV/kicQaec5EaRnc0pIeSnh9LUjj+PYQrJYBURvDt7twGl2PKA7nSN0kz1Zw5bnQ==",
+        "dependencies": {
+          "Microsoft.Build.Tasks.Git": "8.0.0",
+          "Microsoft.SourceLink.Common": "8.0.0"
+        }
+      },
+      "Microsoft.VisualStudio.Threading.Analyzers": {
+        "type": "Direct",
+        "requested": "[17.14.15, )",
+        "resolved": "17.14.15",
+        "contentHash": "mXQPJsbuUD2ydq4/ffd8h8tSOFCXec+2xJOVNCvXjuMOq/+5EKHq3D2m2MC2+nUaXeFMSt66VS/J4HdKBixgcw=="
+      },
       "SimpleExec": {
         "type": "Direct",
         "requested": "[13.0.0, )",
         "resolved": "13.0.0",
         "contentHash": "zcCR1pupa1wI1VqBULRiQKeHKKZOuJhi/K+4V5oO+rHJZlaOD53ViFo1c3PavDoMAfSn/FAXGAWpPoF57rwhYg=="
+      },
+      "Microsoft.Build.Tasks.Git": {
+        "type": "Transitive",
+        "resolved": "8.0.0",
+        "contentHash": "bZKfSIKJRXLTuSzLudMFte/8CempWjVamNUR5eHJizsy+iuOuO/k2gnh7W0dHJmYY0tBf+gUErfluCv5mySAOQ=="
+      },
+      "Microsoft.NETFramework.ReferenceAssemblies.net461": {
+        "type": "Transitive",
+        "resolved": "1.0.3",
+        "contentHash": "AmOJZwCqnOCNp6PPcf9joyogScWLtwy0M1WkqfEQ0M9nYwyDD7EX9ZjscKS5iYnyvteX7kzSKFCKt9I9dXA6mA=="
+      },
+      "Microsoft.SourceLink.Common": {
+        "type": "Transitive",
+        "resolved": "8.0.0",
+        "contentHash": "dk9JPxTCIevS75HyEQ0E4OVAFhB2N+V9ShCXf8Q6FkUQZDkgLI12y679Nym1YqsiSysuQskT7Z+6nUf3yab6Vw=="
       }
     }
   }

docs/API.md

@@ -0,0 +1,489 @@
+# API Quick Reference
+
+Quick reference for commonly used SharpCompress APIs.
+
+## Factory Methods
+
+### Opening Archives
+
+```csharp
+// Auto-detect format
+using (var reader = ReaderFactory.Open(stream))
+{
+    // Works with Zip, Tar, GZip, Rar, 7Zip, etc.
+}
+
+// Specific format - Archive API
+using (var archive = ZipArchive.Open("file.zip"))
+using (var archive = TarArchive.Open("file.tar"))
+using (var archive = RarArchive.Open("file.rar"))
+using (var archive = SevenZipArchive.Open("file.7z"))
+using (var archive = GZipArchive.Open("file.gz"))
+
+// With options
+var options = new ReaderOptions 
+{ 
+    Password = "password",
+    LeaveStreamOpen = true,
+    ArchiveEncoding = new ArchiveEncoding { Default = Encoding.GetEncoding(932) }
+};
+using (var archive = ZipArchive.Open("encrypted.zip", options))
+```
+
+### Creating Archives
+
+```csharp
+// Writer Factory
+using (var writer = WriterFactory.Open(stream, ArchiveType.Zip, CompressionType.Deflate))
+{
+    // Write entries
+}
+
+// Specific writer
+using (var archive = ZipArchive.Create())
+using (var archive = TarArchive.Create())
+using (var archive = GZipArchive.Create())
+
+// With options
+var options = new WriterOptions(CompressionType.Deflate) 
+{ 
+    CompressionLevel = 9,
+    LeaveStreamOpen = false
+};
+using (var archive = ZipArchive.Create())
+{
+    archive.SaveTo("output.zip", options);
+}
+```
+
+---
+
+## Archive API Methods
+
+### Reading/Extracting
+
+```csharp
+using (var archive = ZipArchive.Open("file.zip"))
+{
+    // Get all entries
+    IEnumerable<IEntry> entries = archive.Entries;
+    
+    // Find specific entry
+    var entry = archive.Entries.FirstOrDefault(e => e.Key == "file.txt");
+    
+    // Extract all
+    archive.WriteToDirectory(@"C:\output", new ExtractionOptions
+    {
+        ExtractFullPath = true,
+        Overwrite = true
+    });
+    
+    // Extract single entry
+    var entry = archive.Entries.First();
+    entry.WriteToFile(@"C:\output\file.txt");
+    entry.WriteToFile(@"C:\output\file.txt", new ExtractionOptions { Overwrite = true });
+    
+    // Get entry stream
+    using (var stream = entry.OpenEntryStream())
+    {
+        stream.CopyTo(outputStream);
+    }
+}
+
+// Async variants
+await archive.WriteToDirectoryAsync(@"C:\output", options, cancellationToken);
+using (var stream = await entry.OpenEntryStreamAsync(cancellationToken))
+{
+    // ...
+}
+```
+
+### Entry Properties
+
+```csharp
+foreach (var entry in archive.Entries)
+{
+    string name = entry.Key;              // Entry name/path
+    long size = entry.Size;               // Uncompressed size
+    long compressedSize = entry.CompressedSize;
+    bool isDir = entry.IsDirectory;
+    DateTime? modTime = entry.LastModifiedTime;
+    CompressionType compression = entry.CompressionType;
+}
+```
+
+### Creating Archives
+
+```csharp
+using (var archive = ZipArchive.Create())
+{
+    // Add file
+    archive.AddEntry("file.txt", "C:\\source\\file.txt");
+    
+    // Add multiple files
+    archive.AddAllFromDirectory("C:\\source");
+    archive.AddAllFromDirectory("C:\\source", "*.txt");  // Pattern
+    
+    // Save to file
+    archive.SaveTo("output.zip", CompressionType.Deflate);
+    
+    // Save to stream
+    archive.SaveTo(outputStream, new WriterOptions(CompressionType.Deflate)
+    {
+        CompressionLevel = 9,
+        LeaveStreamOpen = true
+    });
+}
+```
+
+---
+
+## Reader API Methods
+
+### Forward-Only Reading
+
+```csharp
+using (var stream = File.OpenRead("file.zip"))
+using (var reader = ReaderFactory.Open(stream))
+{
+    while (reader.MoveToNextEntry())
+    {
+        IEntry entry = reader.Entry;
+        
+        if (!entry.IsDirectory)
+        {
+            // Extract entry
+            reader.WriteEntryToDirectory(@"C:\output");
+            reader.WriteEntryToFile(@"C:\output\file.txt");
+            
+            // Or get stream
+            using (var entryStream = reader.OpenEntryStream())
+            {
+                entryStream.CopyTo(outputStream);
+            }
+        }
+    }
+}
+
+// Async variants
+while (await reader.MoveToNextEntryAsync())
+{
+    await reader.WriteEntryToFileAsync(@"C:\output\" + reader.Entry.Key, cancellationToken);
+}
+
+// Async extraction
+await reader.WriteAllToDirectoryAsync(@"C:\output", 
+    new ExtractionOptions { ExtractFullPath = true, Overwrite = true },
+    cancellationToken);
+```
+
+---
+
+## Writer API Methods
+
+### Creating Archives (Streaming)
+
+```csharp
+using (var stream = File.Create("output.zip"))
+using (var writer = WriterFactory.Open(stream, ArchiveType.Zip, CompressionType.Deflate))
+{
+    // Write single file
+    using (var fileStream = File.OpenRead("source.txt"))
+    {
+        writer.Write("entry.txt", fileStream, DateTime.Now);
+    }
+    
+    // Write directory
+    writer.WriteAll("C:\\source", "*", SearchOption.AllDirectories);
+    writer.WriteAll("C:\\source", "*.txt", SearchOption.TopDirectoryOnly);
+    
+    // Async variants
+    using (var fileStream = File.OpenRead("source.txt"))
+    {
+        await writer.WriteAsync("entry.txt", fileStream, DateTime.Now, cancellationToken);
+    }
+    
+    await writer.WriteAllAsync("C:\\source", "*", SearchOption.AllDirectories, cancellationToken);
+}
+```
+
+---
+
+## Common Options
+
+### ReaderOptions
+
+```csharp
+var options = new ReaderOptions
+{
+    Password = "password",                          // For encrypted archives
+    LeaveStreamOpen = true,                         // Don't close wrapped stream
+    ArchiveEncoding = new ArchiveEncoding          // Custom character encoding
+    {
+        Default = Encoding.GetEncoding(932)
+    }
+};
+using (var archive = ZipArchive.Open("file.zip", options))
+{
+    // ...
+}
+```
+
+### WriterOptions
+
+```csharp
+var options = new WriterOptions(CompressionType.Deflate)
+{
+    CompressionLevel = 9,                           // 0-9 for Deflate
+    LeaveStreamOpen = true,                         // Don't close stream
+};
+archive.SaveTo("output.zip", options);
+```
+
+### ExtractionOptions
+
+```csharp
+var options = new ExtractionOptions
+{
+    ExtractFullPath = true,                         // Recreate directory structure
+    Overwrite = true,                               // Overwrite existing files
+    PreserveFileTime = true                         // Keep original timestamps
+};
+archive.WriteToDirectory(@"C:\output", options);
+```
+
+---
+
+## Compression Types
+
+### Available Compressions
+
+```csharp
+// For creating archives
+CompressionType.None       // No compression (store)
+CompressionType.Deflate    // DEFLATE (default for ZIP/GZip)
+CompressionType.BZip2      // BZip2
+CompressionType.LZMA       // LZMA (for 7Zip, LZip, XZ)
+CompressionType.PPMd       // PPMd (for ZIP)
+CompressionType.Rar        // RAR compression (read-only)
+
+// For Tar archives
+// Use CompressionType in TarWriter constructor
+using (var writer = TarWriter(stream, CompressionType.GZip))  // Tar.GZip
+using (var writer = TarWriter(stream, CompressionType.BZip2)) // Tar.BZip2
+```
+
+### Archive Types
+
+```csharp
+ArchiveType.Zip
+ArchiveType.Tar
+ArchiveType.GZip
+ArchiveType.BZip2
+ArchiveType.Rar
+ArchiveType.SevenZip
+ArchiveType.XZ
+ArchiveType.ZStandard
+```
+
+---
+
+## Patterns & Examples
+
+### Extract with Error Handling
+
+```csharp
+try
+{
+    using (var archive = ZipArchive.Open("archive.zip", 
+        new ReaderOptions { Password = "password" }))
+    {
+        archive.WriteToDirectory(@"C:\output", new ExtractionOptions
+        {
+            ExtractFullPath = true,
+            Overwrite = true
+        });
+    }
+}
+catch (PasswordRequiredException)
+{
+    Console.WriteLine("Password required");
+}
+catch (InvalidArchiveException)
+{
+    Console.WriteLine("Archive is invalid");
+}
+catch (SharpCompressException ex)
+{
+    Console.WriteLine($"Error: {ex.Message}");
+}
+```
+
+### Extract with Progress
+
+```csharp
+var progress = new Progress<ProgressReport>(report =>
+{
+    Console.WriteLine($"Extracting {report.EntryPath}: {report.PercentComplete}%");
+});
+
+var options = new ReaderOptions { Progress = progress };
+using (var archive = ZipArchive.Open("archive.zip", options))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+```
+
+### Async Extract with Cancellation
+
+```csharp
+var cts = new CancellationTokenSource();
+cts.CancelAfter(TimeSpan.FromMinutes(5));
+
+try
+{
+    using (var archive = ZipArchive.Open("archive.zip"))
+    {
+        await archive.WriteToDirectoryAsync(@"C:\output",
+            new ExtractionOptions { ExtractFullPath = true, Overwrite = true },
+            cts.Token);
+    }
+}
+catch (OperationCanceledException)
+{
+    Console.WriteLine("Extraction cancelled");
+}
+```
+
+### Create with Custom Compression
+
+```csharp
+using (var archive = ZipArchive.Create())
+{
+    archive.AddAllFromDirectory(@"D:\source");
+    
+    // Fastest
+    archive.SaveTo("fast.zip", new WriterOptions(CompressionType.Deflate) 
+    { 
+        CompressionLevel = 1 
+    });
+    
+    // Balanced (default)
+    archive.SaveTo("normal.zip", CompressionType.Deflate);
+    
+    // Best compression
+    archive.SaveTo("best.zip", new WriterOptions(CompressionType.Deflate) 
+    { 
+        CompressionLevel = 9 
+    });
+}
+```
+
+### Stream Processing (No File I/O)
+
+```csharp
+using (var outputStream = new MemoryStream())
+using (var archive = ZipArchive.Create())
+{
+    // Add content from memory
+    using (var contentStream = new MemoryStream(Encoding.UTF8.GetBytes("Hello")))
+    {
+        archive.AddEntry("file.txt", contentStream);
+    }
+    
+    // Save to memory
+    archive.SaveTo(outputStream, CompressionType.Deflate);
+    
+    // Get bytes
+    byte[] archiveBytes = outputStream.ToArray();
+}
+```
+
+### Extract Specific Files
+
+```csharp
+using (var archive = ZipArchive.Open("archive.zip"))
+{
+    var filesToExtract = new[] { "file1.txt", "file2.txt" };
+    
+    foreach (var entry in archive.Entries.Where(e => filesToExtract.Contains(e.Key)))
+    {
+        entry.WriteToFile(@"C:\output\" + entry.Key);
+    }
+}
+```
+
+### List Archive Contents
+
+```csharp
+using (var archive = ZipArchive.Open("archive.zip"))
+{
+    foreach (var entry in archive.Entries)
+    {
+        if (entry.IsDirectory)
+            Console.WriteLine($"[DIR]  {entry.Key}");
+        else
+            Console.WriteLine($"[FILE] {entry.Key} ({entry.Size} bytes)");
+    }
+}
+```
+
+---
+
+## Common Mistakes
+
+### ✗ Wrong - Stream not disposed
+
+```csharp
+var stream = File.OpenRead("archive.zip");
+var archive = ZipArchive.Open(stream);
+archive.WriteToDirectory(@"C:\output");
+// stream not disposed - leaked resource
+```
+
+### ✓ Correct - Using blocks
+
+```csharp
+using (var stream = File.OpenRead("archive.zip"))
+using (var archive = ZipArchive.Open(stream))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+// Both properly disposed
+```
+
+### ✗ Wrong - Mixing API styles
+
+```csharp
+// Loading entire archive then iterating
+using (var archive = ZipArchive.Open("large.zip"))
+{
+    var entries = archive.Entries.ToList();  // Loads all in memory
+    foreach (var e in entries)
+    {
+        e.WriteToFile(...);  // Then extracts each
+    }
+}
+```
+
+### ✓ Correct - Use Reader for large files
+
+```csharp
+// Streaming iteration
+using (var stream = File.OpenRead("large.zip"))
+using (var reader = ReaderFactory.Open(stream))
+{
+    while (reader.MoveToNextEntry())
+    {
+        reader.WriteEntryToDirectory(@"C:\output");
+    }
+}
+```
+
+---
+
+## Related Documentation
+
+- [USAGE.md](USAGE.md) - Complete code examples
+- [FORMATS.md](FORMATS.md) - Supported formats
+- [PERFORMANCE.md](PERFORMANCE.md) - API selection guide

docs/ARCHITECTURE.md

@@ -0,0 +1,659 @@
+# SharpCompress Architecture Guide
+
+This guide explains the internal architecture and design patterns of SharpCompress for contributors.
+
+## Overview
+
+SharpCompress is organized into three main layers:
+
+```
+┌─────────────────────────────────────────┐
+│     User-Facing APIs (Top Layer)        │
+│  Archive, Reader, Writer Factories      │
+├─────────────────────────────────────────┤
+│     Format-Specific Implementations     │
+│  ZipArchive, TarReader, GZipWriter,     │
+│  RarArchive, SevenZipArchive, etc.      │
+├─────────────────────────────────────────┤
+│     Compression & Crypto (Bottom Layer) │
+│  Deflate, LZMA, BZip2, AES, CRC32       │
+└─────────────────────────────────────────┘
+```
+
+---
+
+## Directory Structure
+
+### `src/SharpCompress/`
+
+#### `Archives/` - Archive Implementations
+Contains `IArchive` implementations for seekable, random-access APIs.
+
+**Key Files:**
+- `AbstractArchive.cs` - Base class for all archives
+- `IArchive.cs` - Archive interface definition
+- `ArchiveFactory.cs` - Factory for opening archives
+- Format-specific: `ZipArchive.cs`, `TarArchive.cs`, `RarArchive.cs`, `SevenZipArchive.cs`, `GZipArchive.cs`
+
+**Use Archive API when:**
+- Stream is seekable (file, memory)
+- Need random access to entries
+- Archive fits in memory
+- Simplicity is important
+
+#### `Readers/` - Reader Implementations
+Contains `IReader` implementations for forward-only, non-seekable APIs.
+
+**Key Files:**
+- `AbstractReader.cs` - Base reader class
+- `IReader.cs` - Reader interface
+- `ReaderFactory.cs` - Auto-detection factory
+- `ReaderOptions.cs` - Configuration for readers
+- Format-specific: `ZipReader.cs`, `TarReader.cs`, `GZipReader.cs`, `RarReader.cs`, etc.
+
+**Use Reader API when:**
+- Stream is non-seekable (network, pipe, compressed)
+- Processing large files
+- Memory is limited
+- Forward-only processing is acceptable
+
+#### `Writers/` - Writer Implementations
+Contains `IWriter` implementations for forward-only writing.
+
+**Key Files:**
+- `AbstractWriter.cs` - Base writer class
+- `IWriter.cs` - Writer interface
+- `WriterFactory.cs` - Factory for creating writers
+- `WriterOptions.cs` - Configuration for writers
+- Format-specific: `ZipWriter.cs`, `TarWriter.cs`, `GZipWriter.cs`
+
+#### `Factories/` - Format Detection
+Factory classes for auto-detecting archive format and creating appropriate readers/writers.
+
+**Key Files:**
+- `Factory.cs` - Base factory class
+- `IFactory.cs` - Factory interface
+- Format-specific: `ZipFactory.cs`, `TarFactory.cs`, `RarFactory.cs`, etc.
+
+**How It Works:**
+1. `ReaderFactory.Open(stream)` probes stream signatures
+2. Identifies format by magic bytes
+3. Creates appropriate reader instance
+4. Returns generic `IReader` interface
+
+#### `Common/` - Shared Types
+Common types, options, and enumerations used across formats.
+
+**Key Files:**
+- `IEntry.cs` - Entry interface (file within archive)
+- `Entry.cs` - Entry implementation
+- `ArchiveType.cs` - Enum for archive formats
+- `CompressionType.cs` - Enum for compression methods
+- `ArchiveEncoding.cs` - Character encoding configuration
+- `ExtractionOptions.cs` - Extraction configuration
+- Format-specific headers: `Zip/Headers/`, `Tar/Headers/`, `Rar/Headers/`, etc.
+
+#### `Compressors/` - Compression Algorithms
+Low-level compression streams implementing specific algorithms.
+
+**Algorithms:**
+- `Deflate/` - DEFLATE compression (Zip default)
+- `BZip2/` - BZip2 compression
+- `LZMA/` - LZMA compression (7Zip, XZ, LZip)
+- `PPMd/` - Prediction by Partial Matching (Zip, 7Zip)
+- `ZStandard/` - ZStandard compression (decompression only)
+- `Xz/` - XZ format (decompression only)
+- `Rar/` - RAR-specific unpacking
+- `Arj/`, `Arc/`, `Ace/` - Legacy format decompression
+- `Filters/` - BCJ/BCJ2 filters for executable compression
+
+**Each Compressor:**
+- Implements a `Stream` subclass
+- Provides both compression and decompression
+- Some are read-only (decompression only)
+
+#### `Crypto/` - Encryption & Hashing
+Cryptographic functions and stream wrappers.
+
+**Key Files:**
+- `Crc32Stream.cs` - CRC32 calculation wrapper
+- `BlockTransformer.cs` - Block cipher transformations
+- AES, PKWare, WinZip encryption implementations
+
+#### `IO/` - Stream Utilities
+Stream wrappers and utilities.
+
+**Key Classes:**
+- `SharpCompressStream` - Base stream class
+- `ProgressReportingStream` - Progress tracking wrapper
+- `MarkingBinaryReader` - Binary reader with position marks
+- `BufferedSubStream` - Buffered read-only substream
+- `ReadOnlySubStream` - Read-only view of parent stream
+- `NonDisposingStream` - Prevents wrapped stream disposal
+
+---
+
+## Design Patterns
+
+### 1. Factory Pattern
+
+**Purpose:** Auto-detect format and create appropriate reader/writer.
+
+**Example:**
+```csharp
+// User calls factory
+using (var reader = ReaderFactory.Open(stream))  // Returns IReader
+{
+    while (reader.MoveToNextEntry())
+    {
+        // Process entry
+    }
+}
+
+// Behind the scenes:
+// 1. Factory.Open() probes stream signatures
+// 2. Detects format (Zip, Tar, Rar, etc.)
+// 3. Creates appropriate reader (ZipReader, TarReader, etc.)
+// 4. Returns as generic IReader interface
+```
+
+**Files:**
+- `src/SharpCompress/Factories/ReaderFactory.cs`
+- `src/SharpCompress/Factories/WriterFactory.cs`
+- `src/SharpCompress/Factories/ArchiveFactory.cs`
+
+### 2. Strategy Pattern
+
+**Purpose:** Encapsulate compression algorithms as swappable strategies.
+
+**Example:**
+```csharp
+// Different compression strategies
+CompressionType.Deflate     // DEFLATE
+CompressionType.BZip2       // BZip2
+CompressionType.LZMA        // LZMA
+CompressionType.PPMd        // PPMd
+
+// Writer uses strategy pattern
+var archive = ZipArchive.Create();
+archive.SaveTo("output.zip", CompressionType.Deflate);   // Use Deflate
+archive.SaveTo("output.bz2", CompressionType.BZip2);    // Use BZip2
+```
+
+**Files:**
+- `src/SharpCompress/Compressors/` - Strategy implementations
+
+### 3. Decorator Pattern
+
+**Purpose:** Wrap streams with additional functionality.
+
+**Example:**
+```csharp
+// Progress reporting decorator
+var progressStream = new ProgressReportingStream(baseStream, progressReporter);
+progressStream.Read(buffer, 0, buffer.Length);  // Reports progress
+
+// Non-disposing decorator
+var nonDisposingStream = new NonDisposingStream(baseStream);
+using (var compressor = new DeflateStream(nonDisposingStream))
+{
+    // baseStream won't be disposed when compressor is disposed
+}
+```
+
+**Files:**
+- `src/SharpCompress/IO/ProgressReportingStream.cs`
+- `src/SharpCompress/IO/NonDisposingStream.cs`
+
+### 4. Template Method Pattern
+
+**Purpose:** Define algorithm skeleton in base class, let subclasses fill details.
+
+**Example:**
+```csharp
+// AbstractArchive defines common archive operations
+public abstract class AbstractArchive : IArchive
+{
+    // Template methods
+    public virtual void WriteToDirectory(string destinationDirectory, ExtractionOptions options)
+    {
+        // Common extraction logic
+        foreach (var entry in Entries)
+        {
+            // Call subclass method
+            entry.WriteToFile(destinationPath, options);
+        }
+    }
+    
+    // Subclasses override format-specific details
+    protected abstract Entry CreateEntry(EntryData data);
+}
+```
+
+**Files:**
+- `src/SharpCompress/Archives/AbstractArchive.cs`
+- `src/SharpCompress/Readers/AbstractReader.cs`
+
+### 5. Iterator Pattern
+
+**Purpose:** Provide sequential access to entries.
+
+**Example:**
+```csharp
+// Archive API - provides collection
+IEnumerable<IEntry> entries = archive.Entries;
+foreach (var entry in entries)
+{
+    // Random access - entries already in memory
+}
+
+// Reader API - provides iterator
+IReader reader = ReaderFactory.Open(stream);
+while (reader.MoveToNextEntry())
+{
+    // Forward-only iteration - one entry at a time
+    var entry = reader.Entry;
+}
+```
+
+---
+
+## Key Interfaces
+
+### IArchive - Random Access API
+
+```csharp
+public interface IArchive : IDisposable
+{
+    IEnumerable<IEntry> Entries { get; }
+    
+    void WriteToDirectory(string destinationDirectory, 
+                         ExtractionOptions options = null);
+    
+    IEntry FirstOrDefault(Func<IEntry, bool> predicate);
+    
+    // ... format-specific methods
+}
+```
+
+**Implementations:** `ZipArchive`, `TarArchive`, `RarArchive`, `SevenZipArchive`, `GZipArchive`
+
+### IReader - Forward-Only API
+
+```csharp
+public interface IReader : IDisposable
+{
+    IEntry Entry { get; }
+    
+    bool MoveToNextEntry();
+    
+    void WriteEntryToDirectory(string destinationDirectory,
+                              ExtractionOptions options = null);
+    
+    Stream OpenEntryStream();
+    
+    // ... async variants
+}
+```
+
+**Implementations:** `ZipReader`, `TarReader`, `RarReader`, `GZipReader`, etc.
+
+### IWriter - Writing API
+
+```csharp
+public interface IWriter : IDisposable
+{
+    void Write(string entryPath, Stream source, 
+              DateTime? modificationTime = null);
+    
+    void WriteAll(string sourceDirectory, string searchPattern,
+                 SearchOption searchOption);
+    
+    // ... async variants
+}
+```
+
+**Implementations:** `ZipWriter`, `TarWriter`, `GZipWriter`
+
+### IEntry - Archive Entry
+
+```csharp
+public interface IEntry
+{
+    string Key { get; }
+    uint Size { get; }
+    uint CompressedSize { get; }
+    bool IsDirectory { get; }
+    DateTime? LastModifiedTime { get; }
+    CompressionType CompressionType { get; }
+    
+    void WriteToFile(string fullPath, ExtractionOptions options = null);
+    void WriteToStream(Stream destinationStream);
+    Stream OpenEntryStream();
+    
+    // ... async variants
+}
+```
+
+---
+
+## Adding Support for a New Format
+
+### Step 1: Understand the Format
+- Research format specification
+- Understand compression/encryption used
+- Study existing similar formats in codebase
+
+### Step 2: Create Format Structure Classes
+
+**Create:** `src/SharpCompress/Common/NewFormat/`
+
+```csharp
+// Headers and data structures
+public class NewFormatHeader
+{
+    public uint Magic { get; set; }
+    public ushort Version { get; set; }
+    // ... other fields
+    
+    public static NewFormatHeader Read(BinaryReader reader)
+    {
+        // Deserialize from binary
+    }
+}
+
+public class NewFormatEntry
+{
+    public string FileName { get; set; }
+    public uint CompressedSize { get; set; }
+    public uint UncompressedSize { get; set; }
+    // ... other fields
+}
+```
+
+### Step 3: Create Archive Implementation
+
+**Create:** `src/SharpCompress/Archives/NewFormat/NewFormatArchive.cs`
+
+```csharp
+public class NewFormatArchive : AbstractArchive
+{
+    private NewFormatHeader _header;
+    private List<NewFormatEntry> _entries;
+    
+    public static NewFormatArchive Open(Stream stream)
+    {
+        var archive = new NewFormatArchive();
+        archive._header = NewFormatHeader.Read(stream);
+        archive.LoadEntries(stream);
+        return archive;
+    }
+    
+    public override IEnumerable<IEntry> Entries => _entries.Select(e => new Entry(e));
+    
+    protected override Stream OpenEntryStream(Entry entry)
+    {
+        // Return decompressed stream for entry
+    }
+    
+    // ... other abstract method implementations
+}
+```
+
+### Step 4: Create Reader Implementation
+
+**Create:** `src/SharpCompress/Readers/NewFormat/NewFormatReader.cs`
+
+```csharp
+public class NewFormatReader : AbstractReader
+{
+    private NewFormatHeader _header;
+    private BinaryReader _reader;
+    
+    public NewFormatReader(Stream stream)
+    {
+        _reader = new BinaryReader(stream);
+        _header = NewFormatHeader.Read(_reader);
+    }
+    
+    public override bool MoveToNextEntry()
+    {
+        // Read next entry header
+        if (!_reader.BaseStream.CanRead) return false;
+        
+        var entryData = NewFormatEntry.Read(_reader);
+        // ... set this.Entry
+        return entryData != null;
+    }
+    
+    // ... other abstract method implementations
+}
+```
+
+### Step 5: Create Factory
+
+**Create:** `src/SharpCompress/Factories/NewFormatFactory.cs`
+
+```csharp
+public class NewFormatFactory : Factory, IArchiveFactory, IReaderFactory
+{
+    // Archive format magic bytes (signature)
+    private static readonly byte[] NewFormatSignature = new byte[] { 0x4E, 0x46 };  // "NF"
+    
+    public static NewFormatFactory Instance { get; } = new();
+    
+    public IArchive CreateArchive(Stream stream) 
+        => NewFormatArchive.Open(stream);
+    
+    public IReader CreateReader(Stream stream, ReaderOptions options)
+        => new NewFormatReader(stream) { Options = options };
+    
+    public bool Matches(Stream stream, ReadOnlySpan<byte> signature) 
+        => signature.StartsWith(NewFormatSignature);
+}
+```
+
+### Step 6: Register Factory
+
+**Update:** `src/SharpCompress/Factories/ArchiveFactory.cs`
+
+```csharp
+private static readonly IFactory[] Factories = 
+{
+    ZipFactory.Instance,
+    TarFactory.Instance,
+    RarFactory.Instance,
+    SevenZipFactory.Instance,
+    GZipFactory.Instance,
+    NewFormatFactory.Instance,  // Add here
+    // ... other factories
+};
+```
+
+### Step 7: Add Tests
+
+**Create:** `tests/SharpCompress.Test/NewFormat/NewFormatTests.cs`
+
+```csharp
+public class NewFormatTests : TestBase
+{
+    [Fact]
+    public void NewFormat_Extracts_Successfully()
+    {
+        var archivePath = Path.Combine(TEST_ARCHIVES_PATH, "archive.newformat");
+        using (var archive = NewFormatArchive.Open(archivePath))
+        {
+            archive.WriteToDirectory(SCRATCH_FILES_PATH);
+            // Assert extraction
+        }
+    }
+    
+    [Fact]
+    public void NewFormat_Reader_Works()
+    {
+        var archivePath = Path.Combine(TEST_ARCHIVES_PATH, "archive.newformat");
+        using (var stream = File.OpenRead(archivePath))
+        using (var reader = new NewFormatReader(stream))
+        {
+            Assert.True(reader.MoveToNextEntry());
+            Assert.NotNull(reader.Entry);
+        }
+    }
+}
+```
+
+### Step 8: Add Test Archives
+
+Place test files in `tests/TestArchives/Archives/NewFormat/` directory.
+
+### Step 9: Document
+
+Update `docs/FORMATS.md` with format support information.
+
+---
+
+## Compression Algorithm Implementation
+
+### Creating a New Compression Stream
+
+**Example:** Creating `CustomStream` for a custom compression algorithm
+
+```csharp
+public class CustomStream : Stream
+{
+    private readonly Stream _baseStream;
+    private readonly bool _leaveOpen;
+    
+    public CustomStream(Stream baseStream, bool leaveOpen = false)
+    {
+        _baseStream = baseStream;
+        _leaveOpen = leaveOpen;
+    }
+    
+    public override int Read(byte[] buffer, int offset, int count)
+    {
+        // Decompress data from _baseStream into buffer
+        // Return number of decompressed bytes
+    }
+    
+    public override void Write(byte[] buffer, int offset, int count)
+    {
+        // Compress data from buffer into _baseStream
+    }
+    
+    protected override void Dispose(bool disposing)
+    {
+        if (disposing && !_leaveOpen)
+        {
+            _baseStream?.Dispose();
+        }
+        base.Dispose(disposing);
+    }
+}
+```
+
+---
+
+## Stream Handling Best Practices
+
+### Disposal Pattern
+
+```csharp
+// Correct: Nested using blocks
+using (var fileStream = File.OpenRead("archive.zip"))
+using (var archive = ZipArchive.Open(fileStream))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+// Both archive and fileStream properly disposed
+
+// Correct: Using with options
+var options = new ReaderOptions { LeaveStreamOpen = true };
+var stream = File.OpenRead("archive.zip");
+using (var archive = ZipArchive.Open(stream, options))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+stream.Dispose();  // Manually dispose if LeaveStreamOpen = true
+```
+
+### NonDisposingStream Wrapper
+
+```csharp
+// Prevent unwanted stream closure
+var baseStream = File.OpenRead("data.bin");
+var nonDisposing = new NonDisposingStream(baseStream);
+
+using (var compressor = new DeflateStream(nonDisposing))
+{
+    // Compressor won't close baseStream when disposed
+}
+
+// baseStream still usable
+baseStream.Position = 0;  // Works
+baseStream.Dispose();  // Manual disposal
+```
+
+---
+
+## Performance Considerations
+
+### Memory Efficiency
+
+1. **Avoid loading entire archive in memory** - Use Reader API for large files
+2. **Process entries sequentially** - Especially for solid archives
+3. **Use appropriate buffer sizes** - Larger buffers for network I/O
+4. **Dispose streams promptly** - Free resources when done
+
+### Algorithm Selection
+
+1. **Archive API** - Fast for small archives with random access
+2. **Reader API** - Efficient for large files or streaming
+3. **Solid archives** - Sequential extraction much faster
+4. **Compression levels** - Trade-off between speed and size
+
+---
+
+## Testing Guidelines
+
+### Test Coverage
+
+1. **Happy path** - Normal extraction works
+2. **Edge cases** - Empty archives, single file, many files
+3. **Corrupted data** - Handle gracefully
+4. **Error cases** - Missing passwords, unsupported compression
+5. **Async operations** - Both sync and async code paths
+
+### Test Archives
+
+- Use `tests/TestArchives/` for test data
+- Create format-specific subdirectories
+- Include encrypted, corrupted, and edge case archives
+- Don't recreate existing archives
+
+### Test Patterns
+
+```csharp
+[Fact]
+public void Archive_Extraction_Works()
+{
+    // Arrange
+    var testArchive = Path.Combine(TEST_ARCHIVES_PATH, "test.zip");
+    
+    // Act
+    using (var archive = ZipArchive.Open(testArchive))
+    {
+        archive.WriteToDirectory(SCRATCH_FILES_PATH);
+    }
+    
+    // Assert
+    Assert.True(File.Exists(Path.Combine(SCRATCH_FILES_PATH, "file.txt")));
+}
+```
+
+---
+
+## Related Documentation
+
+- [AGENTS.md](../AGENTS.md) - Development guidelines
+- [FORMATS.md](FORMATS.md) - Supported formats

docs/ENCODING.md

@@ -0,0 +1,610 @@
+# SharpCompress Character Encoding Guide
+
+This guide explains how SharpCompress handles character encoding for archive entries (filenames, comments, etc.).
+
+## Overview
+
+Most archive formats store filenames and metadata as bytes. SharpCompress must convert these bytes to strings using the appropriate character encoding.
+
+**Common Problem:** Archives created on systems with non-UTF8 encodings (especially Japanese, Chinese systems) appear with corrupted filenames when extracted on systems that assume UTF8.
+
+---
+
+## ArchiveEncoding Class
+
+### Basic Usage
+
+```csharp
+using SharpCompress.Common;
+using SharpCompress.Readers;
+
+// Configure encoding before opening archive
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding(932)  // cp932 for Japanese
+    }
+};
+
+using (var archive = ZipArchive.Open("japanese.zip", options))
+{
+    foreach (var entry in archive.Entries)
+    {
+        Console.WriteLine(entry.Key);  // Now shows correct characters
+    }
+}
+```
+
+### ArchiveEncoding Properties
+
+| Property | Purpose |
+|----------|---------|
+| `Default` | Default encoding for filenames (fallback) |
+| `CustomDecoder` | Custom decoding function for special cases |
+
+### Setting for Different APIs
+
+**Archive API:**
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding { Default = Encoding.GetEncoding(932) }
+};
+using (var archive = ZipArchive.Open("file.zip", options))
+{
+    // Use archive with correct encoding
+}
+```
+
+**Reader API:**
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding { Default = Encoding.GetEncoding(932) }
+};
+using (var stream = File.OpenRead("file.zip"))
+using (var reader = ReaderFactory.Open(stream, options))
+{
+    while (reader.MoveToNextEntry())
+    {
+        // Filenames decoded correctly
+    }
+}
+```
+
+---
+
+## Common Encodings
+
+### Asian Encodings
+
+#### cp932 (Japanese)
+```csharp
+// Windows-31J, Shift-JIS variant used on Japanese Windows
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding(932)
+    }
+};
+using (var archive = ZipArchive.Open("japanese.zip", options))
+{
+    // Correctly decodes Japanese filenames
+}
+```
+
+**When to use:**
+- Archives from Japanese Windows systems
+- Files with Japanese characters in names
+
+#### gb2312 (Simplified Chinese)
+```csharp
+// Simplified Chinese
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("gb2312")
+    }
+};
+```
+
+#### gbk (Extended Simplified Chinese)
+```csharp
+// Extended Simplified Chinese (more characters than gb2312)
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("gbk")
+    }
+};
+```
+
+#### big5 (Traditional Chinese)
+```csharp
+// Traditional Chinese (Taiwan, Hong Kong)
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("big5")
+    }
+};
+```
+
+#### euc-jp (Japanese, Unix)
+```csharp
+// Extended Unix Code for Japanese
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("eucjp")
+    }
+};
+```
+
+#### euc-kr (Korean)
+```csharp
+// Extended Unix Code for Korean
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("euc-kr")
+    }
+};
+```
+
+### Western European Encodings
+
+#### iso-8859-1 (Latin-1)
+```csharp
+// Western European (includes accented characters)
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("iso-8859-1")
+    }
+};
+```
+
+**When to use:**
+- Archives from French, German, Spanish systems
+- Files with accented characters (é, ñ, ü, etc.)
+
+#### cp1252 (Windows-1252)
+```csharp
+// Windows Western European
+// Very similar to iso-8859-1 but with additional printable characters
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("cp1252")
+    }
+};
+```
+
+**When to use:**
+- Archives from older Western European Windows systems
+- Files with smart quotes and other Windows-specific characters
+
+#### iso-8859-15 (Latin-9)
+```csharp
+// Western European with Euro symbol support
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("iso-8859-15")
+    }
+};
+```
+
+### Cyrillic Encodings
+
+#### cp1251 (Windows Cyrillic)
+```csharp
+// Russian, Serbian, Bulgarian, etc.
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("cp1251")
+    }
+};
+```
+
+#### koi8-r (KOI8 Russian)
+```csharp
+// Russian (Unix standard)
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("koi8-r")
+    }
+};
+```
+
+### UTF Encodings (Modern)
+
+#### UTF-8 (Default)
+```csharp
+// Modern standard - usually correct for new archives
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.UTF8
+    }
+};
+```
+
+#### UTF-16
+```csharp
+// Unicode - rarely used in archives
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.Unicode
+    }
+};
+```
+
+---
+
+## Encoding Auto-Detection
+
+SharpCompress attempts to auto-detect encoding, but this isn't always reliable:
+
+```csharp
+// Auto-detection (default)
+using (var archive = ZipArchive.Open("file.zip"))  // Uses UTF8 by default
+{
+    // May show corrupted characters if archive uses different encoding
+}
+
+// Explicit encoding (more reliable)
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding { Default = Encoding.GetEncoding(932) }
+};
+using (var archive = ZipArchive.Open("file.zip", options))
+{
+    // Correct characters displayed
+}
+```
+
+### When Manual Override is Needed
+
+| Situation | Solution |
+|-----------|----------|
+| Archive shows corrupted characters | Specify the encoding explicitly |
+| Archives from specific region | Use that region's encoding |
+| Mixed encodings in archive | Use CustomDecoder |
+| Testing with international files | Try different encodings |
+
+---
+
+## Custom Decoder
+
+For complex scenarios where a single encoding isn't sufficient:
+
+### Basic Custom Decoder
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding
+    {
+        CustomDecoder = (data, offset, length) =>
+        {
+            // Custom decoding logic
+            var bytes = new byte[length];
+            Array.Copy(data, offset, bytes, 0, length);
+            
+            // Try UTF8 first
+            try
+            {
+                return Encoding.UTF8.GetString(bytes);
+            }
+            catch
+            {
+                // Fallback to cp932 if UTF8 fails
+                return Encoding.GetEncoding(932).GetString(bytes);
+            }
+        }
+    }
+};
+
+using (var archive = ZipArchive.Open("mixed.zip", options))
+{
+    foreach (var entry in archive.Entries)
+    {
+        Console.WriteLine(entry.Key);  // Uses custom decoder
+    }
+}
+```
+
+### Advanced: Detect Encoding by Content
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding
+    {
+        CustomDecoder = DetectAndDecode
+    }
+};
+
+private static string DetectAndDecode(byte[] data, int offset, int length)
+{
+    var bytes = new byte[length];
+    Array.Copy(data, offset, bytes, 0, length);
+    
+    // Try UTF8 (most modern archives)
+    try
+    {
+        var str = Encoding.UTF8.GetString(bytes);
+        // Verify it decoded correctly (no replacement characters)
+        if (!str.Contains('\uFFFD'))
+            return str;
+    }
+    catch { }
+    
+    // Try cp932 (Japanese)
+    try
+    {
+        var str = Encoding.GetEncoding(932).GetString(bytes);
+        if (!str.Contains('\uFFFD'))
+            return str;
+    }
+    catch { }
+    
+    // Fallback to iso-8859-1 (always succeeds)
+    return Encoding.GetEncoding("iso-8859-1").GetString(bytes);
+}
+```
+
+---
+
+## Code Examples
+
+### Extract Archive with Japanese Filenames
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding(932)  // cp932
+    }
+};
+
+using (var archive = ZipArchive.Open("japanese_files.zip", options))
+{
+    archive.WriteToDirectory(@"C:\output", new ExtractionOptions
+    {
+        ExtractFullPath = true,
+        Overwrite = true
+    });
+}
+// Files extracted with correct Japanese names
+```
+
+### Extract Archive with Western European Filenames
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("iso-8859-1")
+    }
+};
+
+using (var archive = ZipArchive.Open("french_files.zip", options))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+// Accented characters (é, è, ê, etc.) display correctly
+```
+
+### Extract Archive with Chinese Filenames
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("gbk")  // Simplified Chinese
+    }
+};
+
+using (var archive = ZipArchive.Open("chinese_files.zip", options))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+```
+
+### Extract Archive with Russian Filenames
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("cp1251")  // Windows Cyrillic
+    }
+};
+
+using (var archive = ZipArchive.Open("russian_files.zip", options))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+```
+
+### Reader API with Encoding
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding(932)
+    }
+};
+
+using (var stream = File.OpenRead("japanese.zip"))
+using (var reader = ReaderFactory.Open(stream, options))
+{
+    while (reader.MoveToNextEntry())
+    {
+        if (!reader.Entry.IsDirectory)
+        {
+            Console.WriteLine(reader.Entry.Key);  // Correct characters
+            reader.WriteEntryToDirectory(@"C:\output");
+        }
+    }
+}
+```
+
+---
+
+## Creating Archives with Correct Encoding
+
+When creating archives, SharpCompress uses UTF8 by default (recommended):
+
+```csharp
+// Create with UTF8 (default, recommended)
+using (var archive = ZipArchive.Create())
+{
+    archive.AddAllFromDirectory(@"D:\my_files");
+    archive.SaveTo("output.zip", CompressionType.Deflate);
+    // Archives created with UTF8 encoding
+}
+```
+
+If you need to create archives for systems that expect specific encodings:
+
+```csharp
+// Note: SharpCompress Writer API uses UTF8 for encoding
+// To create archives with other encodings, consider:
+// 1. Let users on those systems create archives
+// 2. Use system tools (7-Zip, WinRAR) with desired encoding
+// 3. Post-process archives if absolutely necessary
+
+// For now, recommend modern UTF8-based archives
+```
+
+---
+
+## Troubleshooting Encoding Issues
+
+### Filenames Show Question Marks (?)
+
+```
+✗ Wrong encoding detected
+test文件.txt → test???.txt
+```
+
+**Solution:** Specify correct encoding explicitly
+
+```csharp
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding 
+    { 
+        Default = Encoding.GetEncoding("gbk")  // Try different encodings
+    }
+};
+```
+
+### Filenames Show Replacement Character (￿)
+
+```
+✗ Invalid bytes for selected encoding
+café.txt → caf￿.txt
+```
+
+**Solution:**
+1. Try a different encoding (see Common Encodings table)
+2. Use CustomDecoder with fallback encoding
+3. Archive might be corrupted
+
+### Mixed Encodings in Single Archive
+
+```csharp
+// Use CustomDecoder to handle mixed encodings
+var options = new ReaderOptions
+{
+    ArchiveEncoding = new ArchiveEncoding
+    {
+        CustomDecoder = (data, offset, length) =>
+        {
+            // Try multiple encodings in priority order
+            var bytes = new byte[length];
+            Array.Copy(data, offset, bytes, 0, length);
+            
+            foreach (var encoding in new[] 
+            {
+                Encoding.UTF8,
+                Encoding.GetEncoding(932),
+                Encoding.GetEncoding("iso-8859-1")
+            })
+            {
+                try
+                {
+                    var str = encoding.GetString(bytes);
+                    if (!str.Contains('\uFFFD'))
+                        return str;
+                }
+                catch { }
+            }
+            
+            // Final fallback
+            return Encoding.GetEncoding("iso-8859-1").GetString(bytes);
+        }
+    }
+};
+```
+
+---
+
+## Encoding Reference Table
+
+| Encoding | Code | Use Case |
+|----------|------|----------|
+| UTF-8 | (default) | Modern archives, recommended |
+| cp932 | 932 | Japanese Windows |
+| gb2312 | "gb2312" | Simplified Chinese |
+| gbk | "gbk" | Extended Simplified Chinese |
+| big5 | "big5" | Traditional Chinese |
+| iso-8859-1 | "iso-8859-1" | Western European |
+| cp1252 | "cp1252" | Windows Western European |
+| cp1251 | "cp1251" | Russian/Cyrillic |
+| euc-jp | "euc-jp" | Japanese Unix |
+| euc-kr | "euc-kr" | Korean |
+
+---
+
+## Best Practices
+
+1. **Use UTF-8 for new archives** - Most modern systems support it
+2. **Ask the archive creator** - When receiving archives with corrupted names
+3. **Provide encoding options** - If your app handles user archives
+4. **Document your assumption** - Tell users what encoding you're using
+5. **Test with international files** - Before releasing production code
+
+---
+
+## Related Documentation
+
+- [USAGE.md](USAGE.md#extract-zip-which-has-non-utf8-encoded-filenamycp932) - Usage examples

docs/FORMATS.md

@@ -25,7 +25,7 @@
 | 7Zip (4)               | LZMA, LZMA2, BZip2, PPMd, BCJ, BCJ2, Deflate      | Decompress          | SevenZipArchive | N/A        | N/A           |
 
 1. SOLID Rars are only supported in the RarReader API.
-2. Zip format supports pkware and WinzipAES encryption. However, encrypted LZMA is not supported. Zip64 reading/writing is supported but only with seekable streams as the Zip spec doesn't support Zip64 data in post data descriptors. Deflate64 is only supported for reading. SOZip (Seek-Optimized ZIP) detection is supported for reading. See [Zip Format Notes](#zip-format-notes) for details on multi-volume archives and streaming behavior.
+2. Zip format supports pkware and WinzipAES encryption. However, encrypted LZMA is not supported. Zip64 reading/writing is supported but only with seekable streams as the Zip spec doesn't support Zip64 data in post data descriptors. Deflate64 is only supported for reading. See [Zip Format Notes](#zip-format-notes) for details on multi-volume archives and streaming behavior.
 3. The Tar format requires a file size in the header. If no size is specified to the TarWriter and the stream is not seekable, then an exception will be thrown.
 4. The 7Zip format doesn't allow for reading as a forward-only stream so 7Zip is only supported through the Archive API. See [7Zip Format Notes](#7zip-format-notes) for details on async extraction behavior.
 5. LZip has no support for extra data like the file name or timestamp. There is a default filename used when looking at the entry Key on the archive.

docs/OLD_CHANGELOG.md

@@ -0,0 +1,142 @@
+
+# Version Log
+
+* [Releases](https://github.com/adamhathcock/sharpcompress/releases)
+
+## Version 0.18
+
+* [Now on Github releases](https://github.com/adamhathcock/sharpcompress/releases/tag/0.18)
+
+## Version 0.17.1
+
+* Fix - [Bug Fix for .NET Core on Windows](https://github.com/adamhathcock/sharpcompress/pull/257)
+
+## Version 0.17.0
+
+* New - Full LZip support! Can read and write LZip files and Tars inside LZip files. [Make LZip a first class citizen. #241](https://github.com/adamhathcock/sharpcompress/issues/241)
+* New - XZ read support! Can read XZ files and Tars inside XZ files. [XZ in SharpCompress #91](https://github.com/adamhathcock/sharpcompress/issues/94)
+* Fix - [Regression - zip file writing on seekable streams always assumed stream start was 0. Introduced with Zip64 writing.](https://github.com/adamhathcock/sharpcompress/issues/244)
+* Fix - [Zip files with post-data descriptors can be properly skipped via decompression](https://github.com/adamhathcock/sharpcompress/issues/162)
+
+## Version 0.16.2
+
+* Fix [.NET 3.5 should support files and cryptography (was a regression from 0.16.0)](https://github.com/adamhathcock/sharpcompress/pull/251)
+* Fix [Zip per entry compression customization wrote the wrong method into the zip archive](https://github.com/adamhathcock/sharpcompress/pull/249)
+
+## Version 0.16.1
+
+* Fix [Preserve compression method when getting a compressed stream](https://github.com/adamhathcock/sharpcompress/pull/235)
+* Fix [RAR entry key normalization fix](https://github.com/adamhathcock/sharpcompress/issues/201)
+
+## Version 0.16.0
+
+* Breaking - [Progress Event Tracking rethink](https://github.com/adamhathcock/sharpcompress/pull/226)
+* Update to VS2017 - [VS2017](https://github.com/adamhathcock/sharpcompress/pull/231) - Framework targets have been changed.
+* New - [Add Zip64 writing](https://github.com/adamhathcock/sharpcompress/pull/211)
+* [Fix invalid/mismatching Zip version flags.](https://github.com/adamhathcock/sharpcompress/issues/164) - This allows nuget/System.IO.Packaging to read zip files generated by SharpCompress
+* [Fix 7Zip directory hiding](https://github.com/adamhathcock/sharpcompress/pull/215/files)
+* [Verify RAR CRC headers](https://github.com/adamhathcock/sharpcompress/pull/220)
+
+## Version 0.15.2
+
+* [Fix invalid headers](https://github.com/adamhathcock/sharpcompress/pull/210) - fixes an issue creating large-ish zip archives that was introduced with zip64 reading.
+
+## Version 0.15.1
+
+* [Zip64 extending information and ZipReader](https://github.com/adamhathcock/sharpcompress/pull/206)
+
+## Version 0.15.0
+
+* [Add zip64 support for ZipArchive extraction](https://github.com/adamhathcock/sharpcompress/pull/205)
+
+## Version 0.14.1
+
+* [.NET Assemblies aren't strong named](https://github.com/adamhathcock/sharpcompress/issues/158)
+* [Pkware encryption for Zip files didn't allow for multiple reads of an entry](https://github.com/adamhathcock/sharpcompress/issues/197)
+* [GZip Entry couldn't be read multiple times](https://github.com/adamhathcock/sharpcompress/issues/198)
+
+## Version 0.14.0
+
+* [Support for LZip reading in for Tars](https://github.com/adamhathcock/sharpcompress/pull/191)
+
+## Version 0.13.1
+
+* [Fix null password on ReaderFactory. Fix null options on SevenZipArchive](https://github.com/adamhathcock/sharpcompress/pull/188)
+* [Make PpmdProperties lazy to avoid unnecessary allocations.](https://github.com/adamhathcock/sharpcompress/pull/185)
+
+## Version 0.13.0
+
+* Breaking change: Big refactor of Options on API.
+* 7Zip supports Deflate
+
+## Version 0.12.4
+
+* Forward only zip issue fix https://github.com/adamhathcock/sharpcompress/issues/160
+* Try to fix frameworks again by copying targets from JSON.NET
+
+## Version 0.12.3
+
+* 7Zip fixes https://github.com/adamhathcock/sharpcompress/issues/73
+* Maybe all profiles will work with project.json now
+
+## Version 0.12.2
+
+* Support Profile 259 again
+
+## Version 0.12.1
+
+* Support Silverlight 5
+
+## Version 0.12.0
+
+* .NET Core RTM!
+* Bug fix for Tar long paths
+
+## Version 0.11.6
+
+* Bug fix for global header in Tar
+* Writers now have a leaveOpen `bool` overload. They won't close streams if not-requested to.
+
+## Version 0.11.5
+
+* Bug fix in Skip method
+
+## Version 0.11.4
+
+* SharpCompress is now endian neutral (matters for Mono platforms)
+* Fix for Inflate (need to change implementation)
+* Fixes for RAR detection
+
+## Version 0.11.1
+
+* Added Cancel on IReader
+* Removed .NET 2.0 support and LinqBridge dependency
+
+## Version 0.11
+
+* Been over a year, contains mainly fixes from contributors!
+* Possible breaking change: ArchiveEncoding is UTF8 by default now.
+* TAR supports writing long names using longlink
+* RAR Protect Header added
+
+## Version 0.10.3
+
+* Finally fixed Disposal issue when creating a new archive with the Archive API
+
+## Version 0.10.2
+
+* Fixed Rar Header reading for invalid extended time headers.
+* Windows Store assembly is now strong named
+* Known issues with Long Tar names being worked on
+* Updated to VS2013
+* Portable targets SL5 and Windows Phone 8 (up from SL4 and WP7)
+
+## Version 0.10.1
+
+* Fixed 7Zip extraction performance problem
+
+## Version 0.10:
+
+* Added support for RAR Decryption (thanks to https://github.com/hrasyid)
+* Embedded some BouncyCastle crypto classes to allow RAR Decryption and Winzip AES Decryption in Portable and Windows Store DLLs
+* Built in Release (I think)

docs/PERFORMANCE.md

@@ -0,0 +1,474 @@
+# SharpCompress Performance Guide
+
+This guide helps you optimize SharpCompress for performance in various scenarios.
+
+## API Selection Guide
+
+### Archive API vs Reader API
+
+Choose the right API based on your use case:
+
+| Aspect | Archive API | Reader API |
+|--------|------------|-----------|
+| **Stream Type** | Seekable only | Non-seekable OK |
+| **Memory Usage** | All entries in memory | One entry at a time |
+| **Random Access** | ✓ Yes | ✗ No |
+| **Best For** | Small-to-medium archives | Large or streaming data |
+| **Performance** | Fast for random access | Better for large files |
+
+### Archive API (Fast for Random Access)
+
+```csharp
+// Use when:
+// - Archive fits in memory
+// - You need random access to entries
+// - Stream is seekable (file, MemoryStream)
+
+using (var archive = ZipArchive.Open("archive.zip"))
+{
+    // Random access - all entries available
+    var specific = archive.Entries.FirstOrDefault(e => e.Key == "file.txt");
+    if (specific != null)
+    {
+        specific.WriteToFile(@"C:\output\file.txt");
+    }
+}
+```
+
+**Performance Characteristics:**
+- ✓ Instant entry lookup
+- ✓ Parallel extraction possible
+- ✗ Entire archive in memory
+- ✗ Can't process while downloading
+
+### Reader API (Best for Large Files)
+
+```csharp
+// Use when:
+// - Processing large archives (>100 MB)
+// - Streaming from network/pipe
+// - Memory is constrained
+// - Forward-only processing is acceptable
+
+using (var stream = File.OpenRead("large.zip"))
+using (var reader = ReaderFactory.Open(stream))
+{
+    while (reader.MoveToNextEntry())
+    {
+        // Process one entry at a time
+        reader.WriteEntryToDirectory(@"C:\output");
+    }
+}
+```
+
+**Performance Characteristics:**
+- ✓ Minimal memory footprint
+- ✓ Works with non-seekable streams
+- ✓ Can process while downloading
+- ✗ Forward-only (no random access)
+- ✗ Entry lookup requires iteration
+
+---
+
+## Buffer Sizing
+
+### Understanding Buffers
+
+SharpCompress uses internal buffers for reading compressed data. Buffer size affects:
+- **Speed:** Larger buffers = fewer I/O operations = faster
+- **Memory:** Larger buffers = higher memory usage
+
+### Recommended Buffer Sizes
+
+| Scenario | Size | Notes |
+|----------|------|-------|
+| Embedded/IoT devices | 4-8 KB | Minimal memory usage |
+| Memory-constrained | 16-32 KB | Conservative default |
+| Standard use (default) | 64 KB | Recommended default |
+| Large file streaming | 256 KB | Better throughput |
+| High-speed SSD | 512 KB - 1 MB | Maximum throughput |
+
+### How Buffer Size Affects Performance
+
+```csharp
+// SharpCompress manages buffers internally
+// You can't directly set buffer size, but you can:
+
+// 1. Use Stream.CopyTo with explicit buffer size
+using (var entryStream = reader.OpenEntryStream())
+using (var fileStream = File.Create(@"C:\output\file.txt"))
+{
+    // 64 KB buffer (default)
+    entryStream.CopyTo(fileStream);
+    
+    // Or specify larger buffer for faster copy
+    entryStream.CopyTo(fileStream, bufferSize: 262144);  // 256 KB
+}
+
+// 2. Use custom buffer for writing
+using (var entryStream = reader.OpenEntryStream())
+using (var fileStream = File.Create(@"C:\output\file.txt"))
+{
+    byte[] buffer = new byte[262144];  // 256 KB
+    int bytesRead;
+    while ((bytesRead = entryStream.Read(buffer, 0, buffer.Length)) > 0)
+    {
+        fileStream.Write(buffer, 0, bytesRead);
+    }
+}
+```
+
+---
+
+## Streaming Large Files
+
+### Non-Seekable Stream Patterns
+
+For processing archives from downloads or pipes:
+
+```csharp
+// Download stream (non-seekable)
+using (var httpStream = await httpClient.GetStreamAsync(url))
+using (var reader = ReaderFactory.Open(httpStream))
+{
+    // Process entries as they arrive
+    while (reader.MoveToNextEntry())
+    {
+        if (!reader.Entry.IsDirectory)
+        {
+            reader.WriteEntryToDirectory(@"C:\output");
+        }
+    }
+}
+```
+
+**Performance Tips:**
+- Don't try to buffer the entire stream
+- Process entries immediately
+- Use async APIs for better responsiveness
+
+### Download-Then-Extract vs Streaming
+
+Choose based on your constraints:
+
+| Approach | When to Use |
+|----------|------------|
+| **Download then extract** | Moderate size, need random access |
+| **Stream during download** | Large files, bandwidth limited, memory constrained |
+
+```csharp
+// Download then extract (requires disk space)
+var archivePath = await DownloadFile(url, @"C:\temp\archive.zip");
+using (var archive = ZipArchive.Open(archivePath))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+
+// Stream during download (on-the-fly extraction)
+using (var httpStream = await httpClient.GetStreamAsync(url))
+using (var reader = ReaderFactory.Open(httpStream))
+{
+    while (reader.MoveToNextEntry())
+    {
+        reader.WriteEntryToDirectory(@"C:\output");
+    }
+}
+```
+
+---
+
+## Solid Archive Optimization
+
+### Why Solid Archives Are Slow
+
+Solid archives (Rar, 7Zip) group files together in a single compressed stream:
+
+```
+Solid Archive Layout:
+[Header] [Compressed Stream] [Footer]
+         ├─ File1 compressed data
+         ├─ File2 compressed data
+         ├─ File3 compressed data
+         └─ File4 compressed data
+```
+
+Extracting File3 requires decompressing File1 and File2 first.
+
+### Sequential vs Random Extraction
+
+**Random Extraction (Slow):**
+```csharp
+using (var archive = RarArchive.Open("solid.rar"))
+{
+    foreach (var entry in archive.Entries)
+    {
+        entry.WriteToFile(@"C:\output\" + entry.Key);  // ✗ Slow!
+        // Each entry triggers full decompression from start
+    }
+}
+```
+
+**Sequential Extraction (Fast):**
+```csharp
+using (var archive = RarArchive.Open("solid.rar"))
+{
+    // Method 1: Use WriteToDirectory (recommended)
+    archive.WriteToDirectory(@"C:\output", new ExtractionOptions
+    {
+        ExtractFullPath = true,
+        Overwrite = true
+    });
+    
+    // Method 2: Use ExtractAllEntries
+    archive.ExtractAllEntries();
+    
+    // Method 3: Use Reader API (also sequential)
+    using (var reader = RarReader.Open(File.OpenRead("solid.rar")))
+    {
+        while (reader.MoveToNextEntry())
+        {
+            reader.WriteEntryToDirectory(@"C:\output");
+        }
+    }
+}
+```
+
+**Performance Impact:**
+- Random extraction: O(n²) - very slow for many files
+- Sequential extraction: O(n) - 10-100x faster
+
+### Best Practices for Solid Archives
+
+1. **Always extract sequentially** when possible
+2. **Use Reader API** for large solid archives
+3. **Process entries in order** from the archive
+4. **Consider using 7Zip command-line** for scripted extractions
+
+---
+
+## Compression Level Trade-offs
+
+### Deflate/GZip Levels
+
+```csharp
+// Level 1 = Fastest, largest size
+// Level 6 = Default (balanced)
+// Level 9 = Slowest, best compression
+
+// Write with different compression levels
+using (var archive = ZipArchive.Create())
+{
+    archive.AddAllFromDirectory(@"D:\data");
+    
+    // Fast compression (level 1)
+    archive.SaveTo("fast.zip", new WriterOptions(CompressionType.Deflate)
+    {
+        CompressionLevel = 1
+    });
+    
+    // Default compression (level 6)
+    archive.SaveTo("default.zip", CompressionType.Deflate);
+    
+    // Best compression (level 9)
+    archive.SaveTo("best.zip", new WriterOptions(CompressionType.Deflate)
+    {
+        CompressionLevel = 9
+    });
+}
+```
+
+**Speed vs Size:**
+| Level | Speed | Size | Use Case |
+|-------|-------|------|----------|
+| 1 | 10x | 90% | Network, streaming |
+| 6 | 1x | 75% | Default (good balance) |
+| 9 | 0.1x | 65% | Archival, static storage |
+
+### BZip2 Block Size
+
+```csharp
+// BZip2 block size affects memory and compression
+// 100K to 900K (default 900K)
+
+// Smaller block size = lower memory, faster
+// Larger block size = better compression, slower
+
+using (var archive = TarArchive.Create())
+{
+    archive.AddAllFromDirectory(@"D:\data");
+    
+    // These are preset in WriterOptions via CompressionLevel
+    archive.SaveTo("archive.tar.bz2", CompressionType.BZip2);
+}
+```
+
+### LZMA Settings
+
+LZMA compression is very powerful but memory-intensive:
+
+```csharp
+// LZMA (7Zip, .tar.lzma):
+// - Dictionary size: 16 KB to 1 GB (default 32 MB)
+// - Faster preset: smaller dictionary
+// - Better compression: larger dictionary
+
+// Preset via CompressionType
+using (var archive = TarArchive.Create())
+{
+    archive.AddAllFromDirectory(@"D:\data");
+    archive.SaveTo("archive.tar.xz", CompressionType.LZMA);  // Default settings
+}
+```
+
+---
+
+## Async Performance
+
+### When Async Helps
+
+Async is beneficial when:
+- **Long I/O operations** (network, slow disks)
+- **UI responsiveness** needed (Windows Forms, WPF, Blazor)
+- **Server applications** (ASP.NET, multiple concurrent operations)
+
+```csharp
+// Async extraction (non-blocking)
+using (var archive = ZipArchive.Open("archive.zip"))
+{
+    await archive.WriteToDirectoryAsync(
+        @"C:\output",
+        new ExtractionOptions { ExtractFullPath = true, Overwrite = true },
+        cancellationToken
+    );
+}
+// Thread can handle other work while I/O happens
+```
+
+### When Async Doesn't Help
+
+Async doesn't improve performance for:
+- **CPU-bound operations** (already fast)
+- **Local SSD I/O** (I/O is fast enough)
+- **Single-threaded scenarios** (no parallelism benefit)
+
+```csharp
+// Sync extraction (simpler, same performance on fast I/O)
+using (var archive = ZipArchive.Open("archive.zip"))
+{
+    archive.WriteToDirectory(
+        @"C:\output",
+        new ExtractionOptions { ExtractFullPath = true, Overwrite = true }
+    );
+}
+// Simple and fast - no async needed
+```
+
+### Cancellation Pattern
+
+```csharp
+var cts = new CancellationTokenSource();
+
+// Cancel after 5 minutes
+cts.CancelAfter(TimeSpan.FromMinutes(5));
+
+try
+{
+    using (var archive = ZipArchive.Open("archive.zip"))
+    {
+        await archive.WriteToDirectoryAsync(
+            @"C:\output",
+            new ExtractionOptions { ExtractFullPath = true, Overwrite = true },
+            cts.Token
+        );
+    }
+}
+catch (OperationCanceledException)
+{
+    Console.WriteLine("Extraction cancelled");
+    // Clean up partial extraction if needed
+}
+```
+
+---
+
+## Practical Performance Tips
+
+### 1. Choose the Right API
+
+| Scenario | API | Why |
+|----------|-----|-----|
+| Small archives | Archive | Faster random access |
+| Large archives | Reader | Lower memory |
+| Streaming | Reader | Works on non-seekable streams |
+| Download streams | Reader | Async extraction while downloading |
+
+### 2. Batch Operations
+
+```csharp
+// ✗ Slow - opens each archive separately
+foreach (var file in files)
+{
+    using (var archive = ZipArchive.Open("archive.zip"))
+    {
+        archive.WriteToDirectory(@"C:\output");
+    }
+}
+
+// ✓ Better - process multiple entries at once
+using (var archive = ZipArchive.Open("archive.zip"))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+```
+
+### 3. Profile Your Code
+
+```csharp
+var sw = Stopwatch.StartNew();
+using (var archive = ZipArchive.Open("large.zip"))
+{
+    archive.WriteToDirectory(@"C:\output");
+}
+sw.Stop();
+
+Console.WriteLine($"Extraction took {sw.ElapsedMilliseconds}ms");
+
+// Measure memory before/after
+var beforeMem = GC.GetTotalMemory(true);
+// ... do work ...
+var afterMem = GC.GetTotalMemory(true);
+Console.WriteLine($"Memory used: {(afterMem - beforeMem) / 1024 / 1024}MB");
+```
+
+---
+
+## Troubleshooting Performance
+
+### Extraction is Slow
+
+1. **Check if solid archive** → Use sequential extraction
+2. **Check API** → Reader API might be faster for large files
+3. **Check compression level** → Higher levels are slower to decompress
+4. **Check I/O** → Network drives are much slower than SSD
+5. **Check buffer size** → May need larger buffers for network
+
+### High Memory Usage
+
+1. **Use Reader API** instead of Archive API
+2. **Process entries immediately** rather than buffering
+3. **Reduce compression level** if writing
+4. **Check for memory leaks** in your code
+
+### CPU Usage at 100%
+
+1. **Normal for compression** - especially with high compression levels
+2. **Consider lower level** for faster processing
+3. **Reduce parallelism** if processing multiple archives
+4. **Check if awaiting properly** in async code
+
+---
+
+## Related Documentation
+
+- [PERFORMANCE.md](USAGE.md) - Usage examples with performance considerations
+- [FORMATS.md](FORMATS.md) - Format-specific performance notes

docs/USAGE.md

@@ -1,6 +1,6 @@
 # SharpCompress Usage
 
-## Async/Await Support
+## Async/Await Support (Beta)
 
 SharpCompress now provides full async/await support for all I/O operations. All `Read`, `Write`, and extraction operations have async equivalents ending in `Async` that accept an optional `CancellationToken`. This enables better performance and scalability for I/O-bound operations.
 
@@ -13,7 +13,7 @@ SharpCompress now provides full async/await support for all I/O operations. All
 
 See [Async Examples](#async-examples) section below for usage patterns.
 
-## Stream Rules (changed with 0.21)
+## Stream Rules
 
 When dealing with Streams, the rule should be that you don't close a stream you didn't create. This, in effect, should mean you should always put a Stream in a using block to dispose it. 
 
@@ -113,38 +113,26 @@ using (var archive = RarArchive.Open("Test.rar"))
 }
 ```
 
-### Extract solid Rar or 7Zip archives with manual progress reporting
+### Extract solid Rar or 7Zip archives with progress reporting
 
 `ExtractAllEntries` only works for solid archives (Rar) or 7Zip archives. For optimal performance with these archive types, use this method:
 
 ```C#
-using (var archive = RarArchive.Open("archive.rar")) // Must be solid Rar or 7Zip
+using SharpCompress.Common;
+using SharpCompress.Readers;
+
+var progress = new Progress<ProgressReport>(report =>
 {
-    if (archive.IsSolid || archive.Type == ArchiveType.SevenZip)
+    Console.WriteLine($"Extracting {report.EntryPath}: {report.PercentComplete}%");
+});
+
+using (var archive = RarArchive.Open("archive.rar", new ReaderOptions { Progress = progress })) // Must be solid Rar or 7Zip
+{
+    archive.WriteToDirectory(@"D:\output", new ExtractionOptions()
     {
-        // Calculate total size for progress reporting
-        double totalSize = archive.Entries.Where(e => !e.IsDirectory).Sum(e => e.Size);
-        long completed = 0;
-
-        using (var reader = archive.ExtractAllEntries())
-        {
-            while (reader.MoveToNextEntry())
-            {
-                if (!reader.Entry.IsDirectory)
-                {
-                    reader.WriteEntryToDirectory(@"D:\output", new ExtractionOptions()
-                    {
-                        ExtractFullPath = true,
-                        Overwrite = true
-                    });
-
-                    completed += reader.Entry.Size;
-                    double progress = completed / totalSize;
-                    Console.WriteLine($"Progress: {progress:P}");
-                }
-            }
-        }
-    }
+        ExtractFullPath = true,
+        Overwrite = true
+    });
 }
 ```
 

src/SharpCompress/Archives/AbstractArchive.cs

@@ -1,14 +1,13 @@
-using System;
 using System.Collections.Generic;
-using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.IO;
 using SharpCompress.Readers;
 
 namespace SharpCompress.Archives;
 
-public abstract class AbstractArchive<TEntry, TVolume> : IArchive
+public abstract class AbstractArchive<TEntry, TVolume> : IArchive, IAsyncArchive
     where TEntry : IArchiveEntry
     where TVolume : IVolume
 {
@@ -26,6 +25,12 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive
         _sourceStream = sourceStream;
         _lazyVolumes = new LazyReadOnlyCollection<TVolume>(LoadVolumes(_sourceStream));
         _lazyEntries = new LazyReadOnlyCollection<TEntry>(LoadEntries(Volumes));
+        _lazyVolumesAsync = new LazyAsyncReadOnlyCollection<TVolume>(
+            LoadVolumesAsync(_sourceStream)
+        );
+        _lazyEntriesAsync = new LazyAsyncReadOnlyCollection<TEntry>(
+            LoadEntriesAsync(_lazyVolumesAsync)
+        );
     }
 
     internal AbstractArchive(ArchiveType type)
@@ -34,19 +39,16 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive
         ReaderOptions = new();
         _lazyVolumes = new LazyReadOnlyCollection<TVolume>(Enumerable.Empty<TVolume>());
         _lazyEntries = new LazyReadOnlyCollection<TEntry>(Enumerable.Empty<TEntry>());
+        _lazyVolumesAsync = new LazyAsyncReadOnlyCollection<TVolume>(
+            AsyncEnumerableEx.Empty<TVolume>()
+        );
+        _lazyEntriesAsync = new LazyAsyncReadOnlyCollection<TEntry>(
+            AsyncEnumerableEx.Empty<TEntry>()
+        );
     }
 
     public ArchiveType Type { get; }
 
-    private static Stream CheckStreams(Stream stream)
-    {
-        if (!stream.CanSeek || !stream.CanRead)
-        {
-            throw new ArchiveException("Archive streams must be Readable and Seekable");
-        }
-        return stream;
-    }
-
     /// <summary>
     /// Returns an ReadOnlyCollection of all the RarArchiveEntries across the one or many parts of the RarArchive.
     /// </summary>
@@ -72,6 +74,19 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive
     protected abstract IEnumerable<TVolume> LoadVolumes(SourceStream sourceStream);
     protected abstract IEnumerable<TEntry> LoadEntries(IEnumerable<TVolume> volumes);
 
+    protected virtual IAsyncEnumerable<TVolume> LoadVolumesAsync(SourceStream sourceStream) =>
+        LoadVolumes(sourceStream).ToAsyncEnumerable();
+
+    protected virtual async IAsyncEnumerable<TEntry> LoadEntriesAsync(
+        IAsyncEnumerable<TVolume> volumes
+    )
+    {
+        foreach (var item in LoadEntries(await volumes.ToListAsync()))
+        {
+            yield return item;
+        }
+    }
+
     IEnumerable<IArchiveEntry> IArchive.Entries => Entries.Cast<IArchiveEntry>();
 
     IEnumerable<IVolume> IArchive.Volumes => _lazyVolumes.Cast<IVolume>();
@@ -118,6 +133,7 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive
     }
 
     protected abstract IReader CreateReaderForSolidExtraction();
+    protected abstract ValueTask<IAsyncReader> CreateReaderForSolidExtractionAsync();
 
     /// <summary>
     /// Archive is SOLID (this means the Archive saved bytes by reusing information which helps for archives containing many small files).
@@ -140,4 +156,67 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive
             return Entries.All(x => x.IsComplete);
         }
     }
+
+    #region Async Support
+
+    private readonly LazyAsyncReadOnlyCollection<TVolume> _lazyVolumesAsync;
+    private readonly LazyAsyncReadOnlyCollection<TEntry> _lazyEntriesAsync;
+
+    public virtual async ValueTask DisposeAsync()
+    {
+        if (!_disposed)
+        {
+            await foreach (var v in _lazyVolumesAsync)
+            {
+                v.Dispose();
+            }
+            foreach (var v in _lazyEntriesAsync.GetLoaded().Cast<Entry>())
+            {
+                v.Close();
+            }
+            _sourceStream?.Dispose();
+
+            _disposed = true;
+        }
+    }
+
+    private async ValueTask EnsureEntriesLoadedAsync()
+    {
+        await _lazyEntriesAsync.EnsureFullyLoaded();
+        await _lazyVolumesAsync.EnsureFullyLoaded();
+    }
+
+    public virtual IAsyncEnumerable<TEntry> EntriesAsync => _lazyEntriesAsync;
+    IAsyncEnumerable<IArchiveEntry> IAsyncArchive.EntriesAsync =>
+        EntriesAsync.Cast<TEntry, IArchiveEntry>();
+
+    public IAsyncEnumerable<IVolume> VolumesAsync => _lazyVolumesAsync.Cast<TVolume, IVolume>();
+
+    public async ValueTask<IAsyncReader> ExtractAllEntriesAsync()
+    {
+        if (!IsSolid && Type != ArchiveType.SevenZip)
+        {
+            throw new SharpCompressException(
+                "ExtractAllEntries can only be used on solid archives or 7Zip archives (which require random access)."
+            );
+        }
+        await EnsureEntriesLoadedAsync();
+        return await CreateReaderForSolidExtractionAsync();
+    }
+
+    public virtual ValueTask<bool> IsSolidAsync() => new(false);
+
+    public async ValueTask<bool> IsCompleteAsync()
+    {
+        await EnsureEntriesLoadedAsync();
+        return await EntriesAsync.All(x => x.IsComplete);
+    }
+
+    public async ValueTask<long> TotalSizeAsync() =>
+        await EntriesAsync.Aggregate(0L, (total, cf) => total + cf.CompressedSize);
+
+    public async ValueTask<long> TotalUncompressSizeAsync() =>
+        await EntriesAsync.Aggregate(0L, (total, cf) => total + cf.Size);
+
+    #endregion
 }

src/SharpCompress/Archives/AbstractWritableArchive.cs

@@ -162,7 +162,7 @@ public abstract class AbstractWritableArchive<TEntry, TVolume>
         SaveTo(stream, options, OldEntries, newEntries);
     }
 
-    public async Task SaveToAsync(
+    public async ValueTask SaveToAsync(
         Stream stream,
         WriterOptions options,
         CancellationToken cancellationToken = default
@@ -208,7 +208,7 @@ public abstract class AbstractWritableArchive<TEntry, TVolume>
         IEnumerable<TEntry> newEntries
     );
 
-    protected abstract Task SaveToAsync(
+    protected abstract ValueTask SaveToAsync(
         Stream stream,
         WriterOptions options,
         IEnumerable<TEntry> oldEntries,

src/SharpCompress/Archives/ArchiveFactory.cs

@@ -2,6 +2,8 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Factories;
 using SharpCompress.IO;
@@ -24,6 +26,28 @@ public static class ArchiveFactory
         return FindFactory<IArchiveFactory>(stream).Open(stream, readerOptions);
     }
 
+    /// <summary>
+    /// Opens an Archive for random access asynchronously
+    /// </summary>
+    /// <param name="stream"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    /// <returns></returns>
+    public static async ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        readerOptions ??= new ReaderOptions();
+        stream = SharpCompressStream.Create(stream, bufferSize: readerOptions.BufferSize);
+        var factory = await FindFactoryAsync<IArchiveFactory>(stream, cancellationToken)
+            .ConfigureAwait(false);
+        return await factory
+            .OpenAsync(stream, readerOptions, cancellationToken)
+            .ConfigureAwait(false);
+    }
+
     public static IWritableArchive Create(ArchiveType type)
     {
         var factory = Factory
@@ -49,6 +73,22 @@ public static class ArchiveFactory
         return Open(new FileInfo(filePath), options);
     }
 
+    /// <summary>
+    /// Opens an Archive from a filepath asynchronously.
+    /// </summary>
+    /// <param name="filePath"></param>
+    /// <param name="options"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        string filePath,
+        ReaderOptions? options = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        filePath.NotNullOrEmpty(nameof(filePath));
+        return OpenAsync(new FileInfo(filePath), options, cancellationToken);
+    }
+
     /// <summary>
     /// Constructor with a FileInfo object to an existing file.
     /// </summary>
@@ -61,6 +101,25 @@ public static class ArchiveFactory
         return FindFactory<IArchiveFactory>(fileInfo).Open(fileInfo, options);
     }
 
+    /// <summary>
+    /// Opens an Archive from a FileInfo object asynchronously.
+    /// </summary>
+    /// <param name="fileInfo"></param>
+    /// <param name="options"></param>
+    /// <param name="cancellationToken"></param>
+    public static async ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? options = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        options ??= new ReaderOptions { LeaveStreamOpen = false };
+
+        var factory = await FindFactoryAsync<IArchiveFactory>(fileInfo, cancellationToken)
+            .ConfigureAwait(false);
+        return await factory.OpenAsync(fileInfo, options, cancellationToken).ConfigureAwait(false);
+    }
+
     /// <summary>
     /// Constructor with IEnumerable FileInfo objects, multi and split support.
     /// </summary>
@@ -87,6 +146,40 @@ public static class ArchiveFactory
         return FindFactory<IMultiArchiveFactory>(fileInfo).Open(filesArray, options);
     }
 
+    /// <summary>
+    /// Opens a multi-part archive from files asynchronously.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="options"></param>
+    /// <param name="cancellationToken"></param>
+    public static async ValueTask<IAsyncArchive> OpenAsync(
+        IEnumerable<FileInfo> fileInfos,
+        ReaderOptions? options = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        fileInfos.NotNull(nameof(fileInfos));
+        var filesArray = fileInfos.ToArray();
+        if (filesArray.Length == 0)
+        {
+            throw new InvalidOperationException("No files to open");
+        }
+
+        var fileInfo = filesArray[0];
+        if (filesArray.Length == 1)
+        {
+            return await OpenAsync(fileInfo, options, cancellationToken).ConfigureAwait(false);
+        }
+
+        fileInfo.NotNull(nameof(fileInfo));
+        options ??= new ReaderOptions { LeaveStreamOpen = false };
+
+        var factory = FindFactory<IMultiArchiveFactory>(fileInfo);
+        return await factory
+            .OpenAsync(filesArray, options, cancellationToken)
+            .ConfigureAwait(false);
+    }
+
     /// <summary>
     /// Constructor with IEnumerable FileInfo objects, multi and split support.
     /// </summary>
@@ -113,6 +206,41 @@ public static class ArchiveFactory
         return FindFactory<IMultiArchiveFactory>(firstStream).Open(streamsArray, options);
     }
 
+    /// <summary>
+    /// Opens a multi-part archive from streams asynchronously.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="options"></param>
+    /// <param name="cancellationToken"></param>
+    public static async ValueTask<IAsyncArchive> OpenAsync(
+        IEnumerable<Stream> streams,
+        ReaderOptions? options = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        streams.NotNull(nameof(streams));
+        var streamsArray = streams.ToArray();
+        if (streamsArray.Length == 0)
+        {
+            throw new InvalidOperationException("No streams");
+        }
+
+        var firstStream = streamsArray[0];
+        if (streamsArray.Length == 1)
+        {
+            return await OpenAsync(firstStream, options, cancellationToken).ConfigureAwait(false);
+        }
+
+        firstStream.NotNull(nameof(firstStream));
+        options ??= new ReaderOptions();
+
+        var factory = FindFactory<IMultiArchiveFactory>(firstStream);
+        return await factory
+            .OpenAsync(streamsArray, options, cancellationToken)
+            .ConfigureAwait(false);
+    }
+
     /// <summary>
     /// Extract to specific directory, retaining filename
     /// </summary>
@@ -166,6 +294,52 @@ public static class ArchiveFactory
         );
     }
 
+    private static async ValueTask<T> FindFactoryAsync<T>(
+        FileInfo finfo,
+        CancellationToken cancellationToken
+    )
+        where T : IFactory
+    {
+        finfo.NotNull(nameof(finfo));
+        using Stream stream = finfo.OpenRead();
+        return await FindFactoryAsync<T>(stream, cancellationToken);
+    }
+
+    private static async ValueTask<T> FindFactoryAsync<T>(
+        Stream stream,
+        CancellationToken cancellationToken
+    )
+        where T : IFactory
+    {
+        stream.NotNull(nameof(stream));
+        if (!stream.CanRead || !stream.CanSeek)
+        {
+            throw new ArgumentException("Stream should be readable and seekable");
+        }
+
+        var factories = Factory.Factories.OfType<T>();
+
+        var startPosition = stream.Position;
+
+        foreach (var factory in factories)
+        {
+            stream.Seek(startPosition, SeekOrigin.Begin);
+
+            if (await factory.IsArchiveAsync(stream, cancellationToken: cancellationToken))
+            {
+                stream.Seek(startPosition, SeekOrigin.Begin);
+
+                return factory;
+            }
+        }
+
+        var extensions = string.Join(", ", factories.Select(item => item.Name));
+
+        throw new InvalidOperationException(
+            $"Cannot determine compressed stream type. Supported Archive Formats: {extensions}"
+        );
+    }
+
     public static bool IsArchive(
         string filePath,
         out ArchiveType? type,

src/SharpCompress/Archives/AutoArchiveFactory.cs

@@ -1,12 +1,14 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Readers;
 
 namespace SharpCompress.Archives;
 
-class AutoArchiveFactory : IArchiveFactory
+internal class AutoArchiveFactory : IArchiveFactory
 {
     public string Name => nameof(AutoArchiveFactory);
 
@@ -20,11 +22,30 @@ class AutoArchiveFactory : IArchiveFactory
         int bufferSize = ReaderOptions.DefaultBufferSize
     ) => throw new NotSupportedException();
 
+    public ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize,
+        CancellationToken cancellationToken = default
+    ) => throw new NotSupportedException();
+
     public FileInfo? GetFilePart(int index, FileInfo part1) => throw new NotSupportedException();
 
     public IArchive Open(Stream stream, ReaderOptions? readerOptions = null) =>
         ArchiveFactory.Open(stream, readerOptions);
 
+    public async ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => await ArchiveFactory.OpenAsync(stream, readerOptions, cancellationToken);
+
     public IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null) =>
         ArchiveFactory.Open(fileInfo, readerOptions);
+
+    public async ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => await ArchiveFactory.OpenAsync(fileInfo, readerOptions, cancellationToken);
 }

src/SharpCompress/Archives/GZip/GZipArchive.cs

@@ -102,6 +102,70 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
         );
     }
 
+    /// <summary>
+    /// Opens a GZipArchive asynchronously from a stream.
+    /// </summary>
+    /// <param name="stream"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a GZipArchive asynchronously from a FileInfo.
+    /// </summary>
+    /// <param name="fileInfo"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfo, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a GZipArchive asynchronously from multiple streams.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(streams, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a GZipArchive asynchronously from multiple FileInfo objects.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfos, readerOptions));
+    }
+
     public static GZipArchive Create() => new();
 
     /// <summary>
@@ -138,10 +202,13 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
         SaveTo(stream, new WriterOptions(CompressionType.GZip));
     }
 
-    public Task SaveToAsync(string filePath, CancellationToken cancellationToken = default) =>
+    public ValueTask SaveToAsync(string filePath, CancellationToken cancellationToken = default) =>
         SaveToAsync(new FileInfo(filePath), cancellationToken);
 
-    public async Task SaveToAsync(FileInfo fileInfo, CancellationToken cancellationToken = default)
+    public async ValueTask SaveToAsync(
+        FileInfo fileInfo,
+        CancellationToken cancellationToken = default
+    )
     {
         using var stream = fileInfo.Open(FileMode.Create, FileAccess.Write);
         await SaveToAsync(stream, new WriterOptions(CompressionType.GZip), cancellationToken)
@@ -167,6 +234,28 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
         return true;
     }
 
+    public static async ValueTask<bool> IsGZipFileAsync(
+        Stream stream,
+        CancellationToken cancellationToken = default
+    )
+    {
+        // read the header on the first read
+        byte[] header = new byte[10];
+
+        // workitem 8501: handle edge case (decompress empty stream)
+        if (!await stream.ReadFullyAsync(header, cancellationToken).ConfigureAwait(false))
+        {
+            return false;
+        }
+
+        if (header[0] != 0x1F || header[1] != 0x8B || header[2] != 8)
+        {
+            return false;
+        }
+
+        return true;
+    }
+
     internal GZipArchive()
         : base(ArchiveType.GZip) { }
 
@@ -213,7 +302,7 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
         }
     }
 
-    protected override async Task SaveToAsync(
+    protected override async ValueTask SaveToAsync(
         Stream stream,
         WriterOptions options,
         IEnumerable<GZipArchiveEntry> oldEntries,
@@ -250,4 +339,11 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
         stream.Position = 0;
         return GZipReader.Open(stream);
     }
+
+    protected override ValueTask<IAsyncReader> CreateReaderForSolidExtractionAsync()
+    {
+        var stream = Volumes.Single().Stream;
+        stream.Position = 0;
+        return new(GZipReader.Open(stream));
+    }
 }

src/SharpCompress/Archives/GZip/GZipArchiveEntry.cs

@@ -23,10 +23,12 @@ public class GZipArchiveEntry : GZipEntry, IArchiveEntry
         return Parts.Single().GetCompressedStream().NotNull();
     }
 
-    public virtual Task<Stream> OpenEntryStreamAsync(CancellationToken cancellationToken = default)
+    public async ValueTask<Stream> OpenEntryStreamAsync(
+        CancellationToken cancellationToken = default
+    )
     {
         // GZip synchronous implementation is fast enough, just wrap it
-        return Task.FromResult(OpenEntryStream());
+        return OpenEntryStream();
     }
 
     #region IArchiveEntry Members

src/SharpCompress/Archives/IArchiveEntry.cs

@@ -17,7 +17,7 @@ public interface IArchiveEntry : IEntry
     /// Opens the current entry as a stream that will decompress as it is read asynchronously.
     /// Read the entire stream or use SkipEntry on EntryStream.
     /// </summary>
-    Task<Stream> OpenEntryStreamAsync(CancellationToken cancellationToken = default);
+    ValueTask<Stream> OpenEntryStreamAsync(CancellationToken cancellationToken = default);
 
     /// <summary>
     /// The archive can find all the parts of the archive needed to extract this entry.

src/SharpCompress/Archives/IArchiveEntryExtensions.cs

@@ -37,7 +37,7 @@ public static class IArchiveEntryExtensions
         /// <param name="streamToWriteTo">The stream to write the entry content to.</param>
         /// <param name="cancellationToken">Cancellation token.</param>
         /// <param name="progress">Optional progress reporter for tracking extraction progress.</param>
-        public async Task WriteToAsync(
+        public async ValueTask WriteToAsync(
             Stream streamToWriteTo,
             IProgress<ProgressReport>? progress = null,
             CancellationToken cancellationToken = default
@@ -110,18 +110,20 @@ public static class IArchiveEntryExtensions
         /// <summary>
         /// Extract to specific directory asynchronously, retaining filename
         /// </summary>
-        public Task WriteToDirectoryAsync(
+        public async ValueTask WriteToDirectoryAsync(
             string destinationDirectory,
             ExtractionOptions? options = null,
             CancellationToken cancellationToken = default
         ) =>
-            ExtractionMethods.WriteEntryToDirectoryAsync(
-                entry,
-                destinationDirectory,
-                options,
-                entry.WriteToFileAsync,
-                cancellationToken
-            );
+            await ExtractionMethods
+                .WriteEntryToDirectoryAsync(
+                    entry,
+                    destinationDirectory,
+                    options,
+                    entry.WriteToFileAsync,
+                    cancellationToken
+                )
+                .ConfigureAwait(false);
 
         /// <summary>
         /// Extract to specific file
@@ -141,21 +143,23 @@ public static class IArchiveEntryExtensions
         /// <summary>
         /// Extract to specific file asynchronously
         /// </summary>
-        public Task WriteToFileAsync(
+        public async ValueTask WriteToFileAsync(
             string destinationFileName,
             ExtractionOptions? options = null,
             CancellationToken cancellationToken = default
         ) =>
-            ExtractionMethods.WriteEntryToFileAsync(
-                entry,
-                destinationFileName,
-                options,
-                async (x, fm, ct) =>
-                {
-                    using var fs = File.Open(destinationFileName, fm);
-                    await entry.WriteToAsync(fs, null, ct).ConfigureAwait(false);
-                },
-                cancellationToken
-            );
+            await ExtractionMethods
+                .WriteEntryToFileAsync(
+                    entry,
+                    destinationFileName,
+                    options,
+                    async (x, fm, ct) =>
+                    {
+                        using var fs = File.Open(destinationFileName, fm);
+                        await entry.WriteToAsync(fs, null, ct).ConfigureAwait(false);
+                    },
+                    cancellationToken
+                )
+                .ConfigureAwait(false);
     }
 }

src/SharpCompress/Archives/IArchiveExtensions.cs

@@ -1,8 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Threading;
-using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Readers;
 
@@ -80,89 +78,5 @@ public static class IArchiveExtensions
                 );
             }
         }
-
-        /// <summary>
-        /// Extract to specific directory asynchronously with progress reporting and cancellation support
-        /// </summary>
-        /// <param name="destinationDirectory">The folder to extract into.</param>
-        /// <param name="options">Extraction options.</param>
-        /// <param name="progress">Optional progress reporter for tracking extraction progress.</param>
-        /// <param name="cancellationToken">Optional cancellation token.</param>
-        public async Task WriteToDirectoryAsync(
-            string destinationDirectory,
-            ExtractionOptions? options = null,
-            IProgress<ProgressReport>? progress = null,
-            CancellationToken cancellationToken = default
-        )
-        {
-            // For solid archives (Rar, 7Zip), use the optimized reader-based approach
-            if (archive.IsSolid || archive.Type == ArchiveType.SevenZip)
-            {
-                using var reader = archive.ExtractAllEntries();
-                await reader.WriteAllToDirectoryAsync(
-                    destinationDirectory,
-                    options,
-                    cancellationToken
-                );
-            }
-            else
-            {
-                // For non-solid archives, extract entries directly
-                await archive.WriteToDirectoryAsyncInternal(
-                    destinationDirectory,
-                    options,
-                    progress,
-                    cancellationToken
-                );
-            }
-        }
-
-        private async Task WriteToDirectoryAsyncInternal(
-            string destinationDirectory,
-            ExtractionOptions? options,
-            IProgress<ProgressReport>? progress,
-            CancellationToken cancellationToken
-        )
-        {
-            // Prepare for progress reporting
-            var totalBytes = archive.TotalUncompressSize;
-            var bytesRead = 0L;
-
-            // Tracking for created directories.
-            var seenDirectories = new HashSet<string>();
-
-            // Extract
-            foreach (var entry in archive.Entries)
-            {
-                cancellationToken.ThrowIfCancellationRequested();
-
-                if (entry.IsDirectory)
-                {
-                    var dirPath = Path.Combine(
-                        destinationDirectory,
-                        entry.Key.NotNull("Entry Key is null")
-                    );
-                    if (
-                        Path.GetDirectoryName(dirPath + "/") is { } parentDirectory
-                        && seenDirectories.Add(dirPath)
-                    )
-                    {
-                        Directory.CreateDirectory(parentDirectory);
-                    }
-                    continue;
-                }
-
-                // Use the entry's WriteToDirectoryAsync method which respects ExtractionOptions
-                await entry
-                    .WriteToDirectoryAsync(destinationDirectory, options, cancellationToken)
-                    .ConfigureAwait(false);
-
-                // Update progress
-                bytesRead += entry.Size;
-                progress?.Report(
-                    new ProgressReport(entry.Key ?? string.Empty, bytesRead, totalBytes)
-                );
-            }
-        }
     }
 }

src/SharpCompress/Archives/IArchiveFactory.cs

@@ -1,4 +1,6 @@
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Factories;
 using SharpCompress.Readers;
 
@@ -26,10 +28,34 @@ public interface IArchiveFactory : IFactory
     /// <param name="readerOptions">reading options.</param>
     IArchive Open(Stream stream, ReaderOptions? readerOptions = null);
 
+    /// <summary>
+    /// Opens an Archive for random access asynchronously.
+    /// </summary>
+    /// <param name="stream">An open, readable and seekable stream.</param>
+    /// <param name="readerOptions">reading options.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    );
+
     /// <summary>
     /// Constructor with a FileInfo object to an existing file.
     /// </summary>
     /// <param name="fileInfo">the file to open.</param>
     /// <param name="readerOptions">reading options.</param>
     IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null);
+
+    /// <summary>
+    /// Opens an Archive from a FileInfo object asynchronously.
+    /// </summary>
+    /// <param name="fileInfo">the file to open.</param>
+    /// <param name="readerOptions">reading options.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    );
 }

src/SharpCompress/Archives/IAsyncArchive.cs

@@ -0,0 +1,43 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using SharpCompress.Common;
+using SharpCompress.Readers;
+
+namespace SharpCompress.Archives;
+
+public interface IAsyncArchive : IAsyncDisposable
+{
+    IAsyncEnumerable<IArchiveEntry> EntriesAsync { get; }
+    IAsyncEnumerable<IVolume> VolumesAsync { get; }
+
+    ArchiveType Type { get; }
+
+    /// <summary>
+    /// Use this method to extract all entries in an archive in order.
+    /// This is primarily for SOLID Rar Archives or 7Zip Archives as they need to be
+    /// extracted sequentially for the best performance.
+    /// </summary>
+    ValueTask<IAsyncReader> ExtractAllEntriesAsync();
+
+    /// <summary>
+    /// Archive is SOLID (this means the Archive saved bytes by reusing information which helps for archives containing many small files).
+    /// Rar Archives can be SOLID while all 7Zip archives are considered SOLID.
+    /// </summary>
+    ValueTask<bool> IsSolidAsync();
+
+    /// <summary>
+    /// This checks to see if all the known entries have IsComplete = true
+    /// </summary>
+    ValueTask<bool> IsCompleteAsync();
+
+    /// <summary>
+    /// The total size of the files compressed in the archive.
+    /// </summary>
+    ValueTask<long> TotalSizeAsync();
+
+    /// <summary>
+    /// The total size of the files as uncompressed in the archive.
+    /// </summary>
+    ValueTask<long> TotalUncompressSizeAsync();
+}

src/SharpCompress/Archives/IAsyncArchiveExtensions.cs

@@ -0,0 +1,93 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+using SharpCompress.Common;
+using SharpCompress.Readers;
+
+namespace SharpCompress.Archives;
+
+public static class IAsyncArchiveExtensions
+{
+    /// <summary>
+    /// Extract to specific directory asynchronously with progress reporting and cancellation support
+    /// </summary>
+    /// <param name="archive">The archive to extract.</param>
+    /// <param name="destinationDirectory">The folder to extract into.</param>
+    /// <param name="options">Extraction options.</param>
+    /// <param name="progress">Optional progress reporter for tracking extraction progress.</param>
+    /// <param name="cancellationToken">Optional cancellation token.</param>
+    public static async Task WriteToDirectoryAsync(
+        this IAsyncArchive archive,
+        string destinationDirectory,
+        ExtractionOptions? options = null,
+        IProgress<ProgressReport>? progress = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        // For solid archives (Rar, 7Zip), use the optimized reader-based approach
+        if (await archive.IsSolidAsync() || archive.Type == ArchiveType.SevenZip)
+        {
+            await using var reader = await archive.ExtractAllEntriesAsync();
+            await reader.WriteAllToDirectoryAsync(destinationDirectory, options, cancellationToken);
+        }
+        else
+        {
+            // For non-solid archives, extract entries directly
+            await archive.WriteToDirectoryAsyncInternal(
+                destinationDirectory,
+                options,
+                progress,
+                cancellationToken
+            );
+        }
+    }
+
+    private static async Task WriteToDirectoryAsyncInternal(
+        this IAsyncArchive archive,
+        string destinationDirectory,
+        ExtractionOptions? options,
+        IProgress<ProgressReport>? progress,
+        CancellationToken cancellationToken
+    )
+    {
+        // Prepare for progress reporting
+        var totalBytes = await archive.TotalUncompressSizeAsync();
+        var bytesRead = 0L;
+
+        // Tracking for created directories.
+        var seenDirectories = new HashSet<string>();
+
+        // Extract
+        await foreach (var entry in archive.EntriesAsync.WithCancellation(cancellationToken))
+        {
+            cancellationToken.ThrowIfCancellationRequested();
+
+            if (entry.IsDirectory)
+            {
+                var dirPath = Path.Combine(
+                    destinationDirectory,
+                    entry.Key.NotNull("Entry Key is null")
+                );
+                if (
+                    Path.GetDirectoryName(dirPath + "/") is { } parentDirectory
+                    && seenDirectories.Add(dirPath)
+                )
+                {
+                    Directory.CreateDirectory(parentDirectory);
+                }
+                continue;
+            }
+
+            // Use the entry's WriteToDirectoryAsync method which respects ExtractionOptions
+            await entry
+                .WriteToDirectoryAsync(destinationDirectory, options, cancellationToken)
+                .ConfigureAwait(false);
+
+            // Update progress
+            bytesRead += entry.Size;
+            progress?.Report(new ProgressReport(entry.Key ?? string.Empty, bytesRead, totalBytes));
+        }
+    }
+}

src/SharpCompress/Archives/IMultiArchiveFactory.cs

@@ -1,5 +1,7 @@
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Factories;
 using SharpCompress.Readers;
 
@@ -27,10 +29,34 @@ public interface IMultiArchiveFactory : IFactory
     /// <param name="readerOptions">reading options.</param>
     IArchive Open(IReadOnlyList<Stream> streams, ReaderOptions? readerOptions = null);
 
+    /// <summary>
+    /// Opens a multi-part archive from streams asynchronously.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="readerOptions">reading options.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    );
+
     /// <summary>
     /// Constructor with IEnumerable Stream objects, multi and split support.
     /// </summary>
     /// <param name="fileInfos"></param>
     /// <param name="readerOptions">reading options.</param>
     IArchive Open(IReadOnlyList<FileInfo> fileInfos, ReaderOptions? readerOptions = null);
+
+    /// <summary>
+    /// Opens a multi-part archive from files asynchronously.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="readerOptions">reading options.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    );
 }

src/SharpCompress/Archives/IWritableArchive.cs

@@ -22,7 +22,7 @@ public interface IWritableArchive : IArchive
 
     void SaveTo(Stream stream, WriterOptions options);
 
-    Task SaveToAsync(
+    ValueTask SaveToAsync(
         Stream stream,
         WriterOptions options,
         CancellationToken cancellationToken = default

src/SharpCompress/Archives/IWritableArchiveExtensions.cs

@@ -44,14 +44,14 @@ public static class IWritableArchiveExtensions
         writableArchive.SaveTo(stream, options);
     }
 
-    public static Task SaveToAsync(
+    public static ValueTask SaveToAsync(
         this IWritableArchive writableArchive,
         string filePath,
         WriterOptions options,
         CancellationToken cancellationToken = default
     ) => writableArchive.SaveToAsync(new FileInfo(filePath), options, cancellationToken);
 
-    public static async Task SaveToAsync(
+    public static async ValueTask SaveToAsync(
         this IWritableArchive writableArchive,
         FileInfo fileInfo,
         WriterOptions options,

src/SharpCompress/Archives/Rar/RarArchive.cs

@@ -2,6 +2,8 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Common.Rar;
 using SharpCompress.Common.Rar.Headers;
@@ -65,7 +67,13 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
         return new StreamRarArchiveVolume(sourceStream, ReaderOptions, i++).AsEnumerable();
     }
 
-    protected override IReader CreateReaderForSolidExtraction()
+    protected override IReader CreateReaderForSolidExtraction() =>
+        CreateReaderForSolidExtractionInternal();
+
+    protected override ValueTask<IAsyncReader> CreateReaderForSolidExtractionAsync() =>
+        new(CreateReaderForSolidExtractionInternal());
+
+    private RarReader CreateReaderForSolidExtractionInternal()
     {
         if (this.IsMultipartVolume())
         {
@@ -181,6 +189,70 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
         );
     }
 
+    /// <summary>
+    /// Opens a RarArchive asynchronously from a stream.
+    /// </summary>
+    /// <param name="stream"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a RarArchive asynchronously from a FileInfo.
+    /// </summary>
+    /// <param name="fileInfo"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfo, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a RarArchive asynchronously from multiple streams.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(streams, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a RarArchive asynchronously from multiple FileInfo objects.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfos, readerOptions));
+    }
+
     public static bool IsRarFile(string filePath) => IsRarFile(new FileInfo(filePath));
 
     public static bool IsRarFile(FileInfo fileInfo)

src/SharpCompress/Archives/Rar/RarArchiveEntry.cs

@@ -92,7 +92,9 @@ public class RarArchiveEntry : RarEntry, IArchiveEntry
         return stream;
     }
 
-    public async Task<Stream> OpenEntryStreamAsync(CancellationToken cancellationToken = default)
+    public async ValueTask<Stream> OpenEntryStreamAsync(
+        CancellationToken cancellationToken = default
+    )
     {
         RarStream stream;
         if (IsRarV3)

src/SharpCompress/Archives/SevenZip/SevenZipArchive.cs

@@ -105,6 +105,70 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
         );
     }
 
+    /// <summary>
+    /// Opens a SevenZipArchive asynchronously from a stream.
+    /// </summary>
+    /// <param name="stream"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a SevenZipArchive asynchronously from a FileInfo.
+    /// </summary>
+    /// <param name="fileInfo"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfo, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a SevenZipArchive asynchronously from multiple streams.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(streams, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a SevenZipArchive asynchronously from multiple FileInfo objects.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfos, readerOptions));
+    }
+
     /// <summary>
     /// Constructor with a SourceStream able to handle FileInfo and Streams.
     /// </summary>
@@ -201,6 +265,9 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     protected override IReader CreateReaderForSolidExtraction() =>
         new SevenZipReader(ReaderOptions, this);
 
+    protected override ValueTask<IAsyncReader> CreateReaderForSolidExtractionAsync() =>
+        new(new SevenZipReader(ReaderOptions, this));
+
     public override bool IsSolid =>
         Entries
             .Where(x => !x.IsDirectory)

src/SharpCompress/Archives/SevenZip/SevenZipArchiveEntry.cs

@@ -12,8 +12,9 @@ public class SevenZipArchiveEntry : SevenZipEntry, IArchiveEntry
 
     public Stream OpenEntryStream() => FilePart.GetCompressedStream();
 
-    public Task<Stream> OpenEntryStreamAsync(CancellationToken cancellationToken = default) =>
-        Task.FromResult(OpenEntryStream());
+    public async ValueTask<Stream> OpenEntryStreamAsync(
+        CancellationToken cancellationToken = default
+    ) => OpenEntryStream();
 
     public IArchive Archive { get; }
 

src/SharpCompress/Archives/Tar/TarArchive.cs

@@ -103,6 +103,70 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
         );
     }
 
+    /// <summary>
+    /// Opens a TarArchive asynchronously from a stream.
+    /// </summary>
+    /// <param name="stream"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a TarArchive asynchronously from a FileInfo.
+    /// </summary>
+    /// <param name="fileInfo"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfo, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a TarArchive asynchronously from multiple streams.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(streams, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a TarArchive asynchronously from multiple FileInfo objects.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfos, readerOptions));
+    }
+
     public static bool IsTarFile(string filePath) => IsTarFile(new FileInfo(filePath));
 
     public static bool IsTarFile(FileInfo fileInfo)
@@ -259,7 +323,7 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
         }
     }
 
-    protected override async Task SaveToAsync(
+    protected override async ValueTask SaveToAsync(
         Stream stream,
         WriterOptions options,
         IEnumerable<TarArchiveEntry> oldEntries,
@@ -302,4 +366,11 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
         stream.Position = 0;
         return TarReader.Open(stream);
     }
+
+    protected override ValueTask<IAsyncReader> CreateReaderForSolidExtractionAsync()
+    {
+        var stream = Volumes.Single().Stream;
+        stream.Position = 0;
+        return new(TarReader.Open(stream));
+    }
 }

src/SharpCompress/Archives/Tar/TarArchiveEntry.cs

@@ -14,9 +14,9 @@ public class TarArchiveEntry : TarEntry, IArchiveEntry
 
     public virtual Stream OpenEntryStream() => Parts.Single().GetCompressedStream().NotNull();
 
-    public virtual Task<Stream> OpenEntryStreamAsync(
+    public async ValueTask<Stream> OpenEntryStreamAsync(
         CancellationToken cancellationToken = default
-    ) => Task.FromResult(OpenEntryStream());
+    ) => OpenEntryStream();
 
     #region IArchiveEntry Members
 

src/SharpCompress/Archives/Zip/ZipArchive.cs

@@ -124,6 +124,70 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         );
     }
 
+    /// <summary>
+    /// Opens a ZipArchive asynchronously from a stream.
+    /// </summary>
+    /// <param name="stream"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a ZipArchive asynchronously from a FileInfo.
+    /// </summary>
+    /// <param name="fileInfo"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfo, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a ZipArchive asynchronously from multiple streams.
+    /// </summary>
+    /// <param name="streams"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(streams, readerOptions));
+    }
+
+    /// <summary>
+    /// Opens a ZipArchive asynchronously from multiple FileInfo objects.
+    /// </summary>
+    /// <param name="fileInfos"></param>
+    /// <param name="readerOptions"></param>
+    /// <param name="cancellationToken"></param>
+    public static ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(fileInfos, readerOptions));
+    }
+
     public static bool IsZipFile(
         string filePath,
         string? password = null,
@@ -199,7 +263,95 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
                 if (stream.CanSeek) //could be multipart. Test for central directory - might not be z64 safe
                 {
                     var z = new SeekableZipHeaderFactory(password, new ArchiveEncoding());
-                    var x = z.ReadSeekableHeader(stream).FirstOrDefault();
+                    var x = z.ReadSeekableHeader(stream, useSync: true).FirstOrDefault();
+                    return x?.ZipHeaderType == ZipHeaderType.DirectoryEntry;
+                }
+                else
+                {
+                    return false;
+                }
+            }
+            return Enum.IsDefined(typeof(ZipHeaderType), header.ZipHeaderType);
+        }
+        catch (CryptographicException)
+        {
+            return true;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
+    public static async ValueTask<bool> IsZipFileAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        var headerFactory = new StreamingZipHeaderFactory(password, new ArchiveEncoding(), null);
+        try
+        {
+            if (stream is not SharpCompressStream)
+            {
+                stream = new SharpCompressStream(stream, bufferSize: bufferSize);
+            }
+
+            var header = await headerFactory
+                .ReadStreamHeaderAsync(stream)
+                .Where(x => x.ZipHeaderType != ZipHeaderType.Split)
+                .FirstOrDefaultAsync();
+            if (header is null)
+            {
+                return false;
+            }
+            return Enum.IsDefined(typeof(ZipHeaderType), header.ZipHeaderType);
+        }
+        catch (CryptographicException)
+        {
+            return true;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
+    public static async ValueTask<bool> IsZipMultiAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        var headerFactory = new StreamingZipHeaderFactory(password, new ArchiveEncoding(), null);
+        try
+        {
+            if (stream is not SharpCompressStream)
+            {
+                stream = new SharpCompressStream(stream, bufferSize: bufferSize);
+            }
+
+            var header = headerFactory
+                .ReadStreamHeader(stream)
+                .FirstOrDefault(x => x.ZipHeaderType != ZipHeaderType.Split);
+            if (header is null)
+            {
+                if (stream.CanSeek) //could be multipart. Test for central directory - might not be z64 safe
+                {
+                    var z = new SeekableZipHeaderFactory(password, new ArchiveEncoding());
+                    ZipHeader? x = null;
+                    await foreach (
+                        var h in z.ReadSeekableHeaderAsync(stream)
+                            .WithCancellation(cancellationToken)
+                    )
+                    {
+                        x = h;
+                        break;
+                    }
                     return x?.ZipHeaderType == ZipHeaderType.DirectoryEntry;
                 }
                 else
@@ -254,7 +406,9 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
     protected override IEnumerable<ZipArchiveEntry> LoadEntries(IEnumerable<ZipVolume> volumes)
     {
         var vols = volumes.ToArray();
-        foreach (var h in headerFactory.NotNull().ReadSeekableHeader(vols.Last().Stream))
+        foreach (
+            var h in headerFactory.NotNull().ReadSeekableHeader(vols.Last().Stream, useSync: true)
+        )
         {
             if (h != null)
             {
@@ -298,6 +452,59 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         }
     }
 
+    protected override async IAsyncEnumerable<ZipArchiveEntry> LoadEntriesAsync(
+        IAsyncEnumerable<ZipVolume> volumes
+    )
+    {
+        var vols = await volumes.ToListAsync();
+        var volsArray = vols.ToArray();
+
+        await foreach (
+            var h in headerFactory.NotNull().ReadSeekableHeaderAsync(volsArray.Last().Stream)
+        )
+        {
+            if (h != null)
+            {
+                switch (h.ZipHeaderType)
+                {
+                    case ZipHeaderType.DirectoryEntry:
+                        {
+                            var deh = (DirectoryEntryHeader)h;
+                            Stream s;
+                            if (
+                                deh.RelativeOffsetOfEntryHeader + deh.CompressedSize
+                                > volsArray[deh.DiskNumberStart].Stream.Length
+                            )
+                            {
+                                var v = volsArray.Skip(deh.DiskNumberStart).ToArray();
+                                s = new SourceStream(
+                                    v[0].Stream,
+                                    i => i < v.Length ? v[i].Stream : null,
+                                    new ReaderOptions() { LeaveStreamOpen = true }
+                                );
+                            }
+                            else
+                            {
+                                s = volsArray[deh.DiskNumberStart].Stream;
+                            }
+
+                            yield return new ZipArchiveEntry(
+                                this,
+                                new SeekableZipFilePart(headerFactory.NotNull(), deh, s)
+                            );
+                        }
+                        break;
+                    case ZipHeaderType.DirectoryEnd:
+                    {
+                        var bytes = ((DirectoryEndHeader)h).Comment ?? Array.Empty<byte>();
+                        volsArray.Last().Comment = ReaderOptions.ArchiveEncoding.Decode(bytes);
+                        yield break;
+                    }
+                }
+            }
+        }
+    }
+
     public void SaveTo(Stream stream) => SaveTo(stream, new WriterOptions(CompressionType.Deflate));
 
     protected override void SaveTo(
@@ -329,7 +536,7 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         }
     }
 
-    protected override async Task SaveToAsync(
+    protected override async ValueTask SaveToAsync(
         Stream stream,
         WriterOptions options,
         IEnumerable<ZipArchiveEntry> oldEntries,
@@ -385,4 +592,11 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         ((IStreamStack)stream).StackSeek(0);
         return ZipReader.Open(stream, ReaderOptions, Entries);
     }
+
+    protected override ValueTask<IAsyncReader> CreateReaderForSolidExtractionAsync()
+    {
+        var stream = Volumes.Single().Stream;
+        stream.Position = 0;
+        return new(ZipReader.Open(stream));
+    }
 }

src/SharpCompress/Archives/Zip/ZipArchiveEntry.cs

@@ -13,9 +13,17 @@ public class ZipArchiveEntry : ZipEntry, IArchiveEntry
 
     public virtual Stream OpenEntryStream() => Parts.Single().GetCompressedStream().NotNull();
 
-    public virtual Task<Stream> OpenEntryStreamAsync(
+    public async ValueTask<Stream> OpenEntryStreamAsync(
         CancellationToken cancellationToken = default
-    ) => Task.FromResult(OpenEntryStream());
+    )
+    {
+        var part = Parts.Single();
+        if (part is SeekableZipFilePart seekablePart)
+        {
+            return (await seekablePart.GetCompressedStreamAsync(cancellationToken)).NotNull();
+        }
+        return OpenEntryStream();
+    }
 
     #region IArchiveEntry Members
 

src/SharpCompress/Common/Ace/Headers/AceFileHeader.cs

@@ -46,7 +46,7 @@ namespace SharpCompress.Common.Ace.Headers
             }
         }
 
-        public AceFileHeader(ArchiveEncoding archiveEncoding)
+        public AceFileHeader(IArchiveEncoding archiveEncoding)
             : base(archiveEncoding, AceHeaderType.FILE) { }
 
         /// <summary>

src/SharpCompress/Common/Ace/Headers/AceHeader.cs

@@ -31,13 +31,13 @@ namespace SharpCompress.Common.Ace.Headers
             (byte)'*',
         ];
 
-        public AceHeader(ArchiveEncoding archiveEncoding, AceHeaderType type)
+        public AceHeader(IArchiveEncoding archiveEncoding, AceHeaderType type)
         {
             AceHeaderType = type;
             ArchiveEncoding = archiveEncoding;
         }
 
-        public ArchiveEncoding ArchiveEncoding { get; }
+        public IArchiveEncoding ArchiveEncoding { get; }
         public AceHeaderType AceHeaderType { get; }
 
         public ushort HeaderFlags { get; set; }

src/SharpCompress/Common/Ace/Headers/AceMainHeader.cs

@@ -22,7 +22,7 @@ namespace SharpCompress.Common.Ace.Headers
         public List<byte> Comment { get; set; } = new();
         public byte AceVersion { get; private set; }
 
-        public AceMainHeader(ArchiveEncoding archiveEncoding)
+        public AceMainHeader(IArchiveEncoding archiveEncoding)
             : base(archiveEncoding, AceHeaderType.MAIN) { }
 
         /// <summary>

src/SharpCompress/Common/Arc/ArcEntryHeader.cs

@@ -7,7 +7,7 @@ namespace SharpCompress.Common.Arc
 {
     public class ArcEntryHeader
     {
-        public ArchiveEncoding ArchiveEncoding { get; }
+        public IArchiveEncoding ArchiveEncoding { get; }
         public CompressionType CompressionMethod { get; private set; }
         public string? Name { get; private set; }
         public long CompressedSize { get; private set; }
@@ -16,7 +16,7 @@ namespace SharpCompress.Common.Arc
         public long OriginalSize { get; private set; }
         public long DataStartPosition { get; private set; }
 
-        public ArcEntryHeader(ArchiveEncoding archiveEncoding)
+        public ArcEntryHeader(IArchiveEncoding archiveEncoding)
         {
             this.ArchiveEncoding = archiveEncoding;
         }

src/SharpCompress/Common/ArchiveEncoding.cs

@@ -3,55 +3,11 @@ using System.Text;
 
 namespace SharpCompress.Common;
 
-public class ArchiveEncoding
+public class ArchiveEncoding : IArchiveEncoding
 {
-    /// <summary>
-    /// Default encoding to use when archive format doesn't specify one.
-    /// </summary>
-    public Encoding? Default { get; set; }
-
-    /// <summary>
-    /// ArchiveEncoding used by encryption schemes which don't comply with RFC 2898.
-    /// </summary>
-    public Encoding? Password { get; set; }
-
-    /// <summary>
-    /// Set this encoding when you want to force it for all encoding operations.
-    /// </summary>
+    public Encoding Default { get; set; } = Encoding.Default;
+    public Encoding Password { get; set; } = Encoding.Default;
+    public Encoding UTF8 { get; set; } = Encoding.UTF8;
     public Encoding? Forced { get; set; }
-
-    /// <summary>
-    /// Set this when you want to use a custom method for all decoding operations.
-    /// </summary>
-    /// <returns>string Func(bytes, index, length)</returns>
-    public Func<byte[], int, int, string>? CustomDecoder { get; set; }
-
-    public ArchiveEncoding()
-        : this(Encoding.Default, Encoding.Default) { }
-
-    public ArchiveEncoding(Encoding def, Encoding password)
-    {
-        Default = def;
-        Password = password;
-    }
-
-#if !NETFRAMEWORK
-    static ArchiveEncoding() => Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
-#endif
-
-    public string Decode(byte[] bytes) => Decode(bytes, 0, bytes.Length);
-
-    public string Decode(byte[] bytes, int start, int length) =>
-        GetDecoder().Invoke(bytes, start, length);
-
-    public string DecodeUTF8(byte[] bytes) => Encoding.UTF8.GetString(bytes, 0, bytes.Length);
-
-    public byte[] Encode(string str) => GetEncoding().GetBytes(str);
-
-    public Encoding GetEncoding() => Forced ?? Default ?? Encoding.UTF8;
-
-    public Encoding GetPasswordEncoding() => Password ?? Encoding.UTF8;
-
-    public Func<byte[], int, int, string> GetDecoder() =>
-        CustomDecoder ?? ((bytes, index, count) => GetEncoding().GetString(bytes, index, count));
+    public Func<byte[], int, int, EncodingType, string>? CustomDecoder { get; set; }
 }

src/SharpCompress/Common/ArchiveEncodingExtensions.cs

@@ -0,0 +1,87 @@
+using System;
+using System.Text;
+
+namespace SharpCompress.Common;
+
+/// <summary>
+/// Specifies the type of encoding to use.
+/// </summary>
+public enum EncodingType
+{
+    /// <summary>
+    /// Uses the default encoding.
+    /// </summary>
+    Default,
+
+    /// <summary>
+    /// Uses UTF-8 encoding.
+    /// </summary>
+    UTF8,
+}
+
+/// <summary>
+/// Provides extension methods for archive encoding.
+/// </summary>
+public static class ArchiveEncodingExtensions
+{
+#if !NETFRAMEWORK
+    /// <summary>
+    /// Registers the code pages encoding provider.
+    /// </summary>
+    static ArchiveEncodingExtensions() =>
+        Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
+#endif
+
+    extension(IArchiveEncoding encoding)
+    {
+        /// <summary>
+        /// Gets the encoding based on the archive encoding settings.
+        /// </summary>
+        /// <param name="useUtf8">Whether to use UTF-8.</param>
+        /// <returns>The encoding.</returns>
+        public Encoding GetEncoding(bool useUtf8 = false) =>
+            encoding.Forced ?? (useUtf8 ? encoding.UTF8 : encoding.Default);
+
+        /// <summary>
+        /// Gets the decoder function for the archive encoding.
+        /// </summary>
+        /// <returns>The decoder function.</returns>
+        public Func<byte[], int, int, EncodingType, string> GetDecoder() =>
+            encoding.CustomDecoder
+            ?? (
+                (bytes, index, count, type) =>
+                    encoding.GetEncoding(type == EncodingType.UTF8).GetString(bytes, index, count)
+            );
+
+        /// <summary>
+        /// Encodes a string using the default encoding.
+        /// </summary>
+        /// <param name="str">The string to encode.</param>
+        /// <returns>The encoded bytes.</returns>
+        public byte[] Encode(string str) => encoding.Default.GetBytes(str);
+
+        /// <summary>
+        /// Decodes bytes using the specified encoding type.
+        /// </summary>
+        /// <param name="bytes">The bytes to decode.</param>
+        /// <param name="type">The encoding type.</param>
+        /// <returns>The decoded string.</returns>
+        public string Decode(byte[] bytes, EncodingType type = EncodingType.Default) =>
+            encoding.Decode(bytes, 0, bytes.Length, type);
+
+        /// <summary>
+        /// Decodes a portion of bytes using the specified encoding type.
+        /// </summary>
+        /// <param name="bytes">The bytes to decode.</param>
+        /// <param name="start">The start index.</param>
+        /// <param name="length">The length.</param>
+        /// <param name="type">The encoding type.</param>
+        /// <returns>The decoded string.</returns>
+        public string Decode(
+            byte[] bytes,
+            int start,
+            int length,
+            EncodingType type = EncodingType.Default
+        ) => encoding.GetDecoder()(bytes, start, length, type);
+    }
+}

src/SharpCompress/Common/AsyncBinaryReader.cs

@@ -0,0 +1,95 @@
+using System;
+using System.Buffers.Binary;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace SharpCompress.Common
+{
+    public sealed class AsyncBinaryReader : IDisposable
+    {
+        private readonly Stream _stream;
+        private readonly Stream _originalStream;
+        private readonly bool _leaveOpen;
+        private readonly byte[] _buffer = new byte[8];
+        private bool _disposed;
+
+        public AsyncBinaryReader(Stream stream, bool leaveOpen = false, int bufferSize = 4096)
+        {
+            _originalStream = stream ?? throw new ArgumentNullException(nameof(stream));
+            _leaveOpen = leaveOpen;
+
+            // Use the stream directly without wrapping in BufferedStream
+            // BufferedStream uses synchronous Read internally which doesn't work with async-only streams
+            // SharpCompress uses SharpCompressStream for buffering which supports true async reads
+            _stream = stream;
+        }
+
+        public Stream BaseStream => _stream;
+
+        public async ValueTask<byte> ReadByteAsync(CancellationToken ct = default)
+        {
+            await _stream.ReadExactAsync(_buffer, 0, 1, ct).ConfigureAwait(false);
+            return _buffer[0];
+        }
+
+        public async ValueTask<ushort> ReadUInt16Async(CancellationToken ct = default)
+        {
+            await _stream.ReadExactAsync(_buffer, 0, 2, ct).ConfigureAwait(false);
+            return BinaryPrimitives.ReadUInt16LittleEndian(_buffer);
+        }
+
+        public async ValueTask<uint> ReadUInt32Async(CancellationToken ct = default)
+        {
+            await _stream.ReadExactAsync(_buffer, 0, 4, ct).ConfigureAwait(false);
+            return BinaryPrimitives.ReadUInt32LittleEndian(_buffer);
+        }
+
+        public async ValueTask<ulong> ReadUInt64Async(CancellationToken ct = default)
+        {
+            await _stream.ReadExactAsync(_buffer, 0, 8, ct).ConfigureAwait(false);
+            return BinaryPrimitives.ReadUInt64LittleEndian(_buffer);
+        }
+
+        public async ValueTask<byte[]> ReadBytesAsync(int count, CancellationToken ct = default)
+        {
+            var result = new byte[count];
+            await _stream.ReadExactAsync(result, 0, count, ct).ConfigureAwait(false);
+            return result;
+        }
+
+        public void Dispose()
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            _disposed = true;
+
+            // Dispose the original stream if we own it
+            if (!_leaveOpen)
+            {
+                _originalStream.Dispose();
+            }
+        }
+
+#if NET6_0_OR_GREATER
+        public async ValueTask DisposeAsync()
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            _disposed = true;
+
+            // Dispose the original stream if we own it
+            if (!_leaveOpen)
+            {
+                await _originalStream.DisposeAsync().ConfigureAwait(false);
+            }
+        }
+#endif
+    }
+}

src/SharpCompress/Common/EntryStream.cs

@@ -56,7 +56,7 @@ public class EntryStream : Stream, IStreamStack
     /// <summary>
     /// Asynchronously skip the rest of the entry stream.
     /// </summary>
-    public async Task SkipEntryAsync(CancellationToken cancellationToken = default)
+    public async ValueTask SkipEntryAsync(CancellationToken cancellationToken = default)
     {
         await this.SkipAsync(cancellationToken).ConfigureAwait(false);
         _completed = true;

src/SharpCompress/Common/ExtractionMethods.cs

@@ -124,11 +124,11 @@ internal static class ExtractionMethods
         }
     }
 
-    public static async Task WriteEntryToDirectoryAsync(
+    public static async ValueTask WriteEntryToDirectoryAsync(
         IEntry entry,
         string destinationDirectory,
         ExtractionOptions? options,
-        Func<string, ExtractionOptions?, CancellationToken, Task> writeAsync,
+        Func<string, ExtractionOptions?, CancellationToken, ValueTask> writeAsync,
         CancellationToken cancellationToken = default
     )
     {
@@ -197,11 +197,11 @@ internal static class ExtractionMethods
         }
     }
 
-    public static async Task WriteEntryToFileAsync(
+    public static async ValueTask WriteEntryToFileAsync(
         IEntry entry,
         string destinationFileName,
         ExtractionOptions? options,
-        Func<string, FileMode, CancellationToken, Task> openAndWriteAsync,
+        Func<string, FileMode, CancellationToken, ValueTask> openAndWriteAsync,
         CancellationToken cancellationToken = default
     )
     {

src/SharpCompress/Common/FilePart.cs

@@ -1,12 +1,14 @@
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common;
 
 public abstract class FilePart
 {
-    protected FilePart(ArchiveEncoding archiveEncoding) => ArchiveEncoding = archiveEncoding;
+    protected FilePart(IArchiveEncoding archiveEncoding) => ArchiveEncoding = archiveEncoding;
 
-    internal ArchiveEncoding ArchiveEncoding { get; }
+    internal IArchiveEncoding ArchiveEncoding { get; }
 
     internal abstract string? FilePartName { get; }
     public int Index { get; set; }
@@ -14,4 +16,8 @@ public abstract class FilePart
     internal abstract Stream? GetCompressedStream();
     internal abstract Stream? GetRawStream();
     internal bool Skipped { get; set; }
+
+    internal virtual ValueTask<Stream?> GetCompressedStreamAsync(
+        CancellationToken cancellationToken = default
+    ) => new(GetCompressedStream());
 }

src/SharpCompress/Common/GZip/GZipFilePart.cs

@@ -13,7 +13,7 @@ internal sealed class GZipFilePart : FilePart
     private string? _name;
     private readonly Stream _stream;
 
-    internal GZipFilePart(Stream stream, ArchiveEncoding archiveEncoding)
+    internal GZipFilePart(Stream stream, IArchiveEncoding archiveEncoding)
         : base(archiveEncoding)
     {
         _stream = stream;

src/SharpCompress/Common/IArchiveEncoding.cs

@@ -0,0 +1,36 @@
+using System;
+using System.Text;
+
+namespace SharpCompress.Common;
+
+/// <summary>
+/// Defines the encoding settings for archives.
+/// </summary>
+public interface IArchiveEncoding
+{
+    /// <summary>
+    /// Default encoding to use when archive format doesn't specify one.  Required and defaults to Encoding.Default.
+    /// </summary>
+    public Encoding Default { get; set; }
+
+    /// <summary>
+    /// ArchiveEncoding used by encryption schemes which don't comply with RFC 2898. Required and defaults to Encoding.Default.
+    /// </summary>
+    public Encoding Password { get; set; }
+
+    /// <summary>
+    /// Default encoding to use when archive format specifies UTF-8 encoding. Required and defaults to Encoding.UTF8.
+    /// </summary>
+    public Encoding UTF8 { get; set; }
+
+    /// <summary>
+    /// Set this encoding when you want to force it for all encoding operations.
+    /// </summary>
+    public Encoding? Forced { get; set; }
+
+    /// <summary>
+    /// Set this when you want to use a custom method for all decoding operations.
+    /// </summary>
+    /// <returns>string Func(bytes, index, length, EncodingType)</returns>
+    public Func<byte[], int, int, EncodingType, string>? CustomDecoder { get; set; }
+}

src/SharpCompress/Common/OptionsBase.cs

@@ -7,5 +7,5 @@ public class OptionsBase
     /// </summary>
     public bool LeaveStreamOpen { get; set; } = true;
 
-    public ArchiveEncoding ArchiveEncoding { get; set; } = new();
+    public IArchiveEncoding ArchiveEncoding { get; set; } = new ArchiveEncoding();
 }

src/SharpCompress/Common/Rar/Headers/RarHeader.cs

@@ -13,7 +13,7 @@ internal class RarHeader : IRarHeader
     internal static RarHeader? TryReadBase(
         RarCrcBinaryReader reader,
         bool isRar5,
-        ArchiveEncoding archiveEncoding
+        IArchiveEncoding archiveEncoding
     )
     {
         try
@@ -26,7 +26,7 @@ internal class RarHeader : IRarHeader
         }
     }
 
-    private RarHeader(RarCrcBinaryReader reader, bool isRar5, ArchiveEncoding archiveEncoding)
+    private RarHeader(RarCrcBinaryReader reader, bool isRar5, IArchiveEncoding archiveEncoding)
     {
         _headerType = HeaderType.Null;
         _isRar5 = isRar5;
@@ -115,7 +115,7 @@ internal class RarHeader : IRarHeader
 
     protected int HeaderSize { get; }
 
-    internal ArchiveEncoding ArchiveEncoding { get; }
+    internal IArchiveEncoding ArchiveEncoding { get; }
 
     /// <summary>
     /// Extra header size.

src/SharpCompress/Common/SevenZip/SevenZipFilePart.cs

@@ -15,7 +15,7 @@ internal class SevenZipFilePart : FilePart
         ArchiveDatabase database,
         int index,
         CFileItem fileEntry,
-        ArchiveEncoding archiveEncoding
+        IArchiveEncoding archiveEncoding
     )
         : base(archiveEncoding)
     {
@@ -55,7 +55,7 @@ internal class SevenZipFilePart : FilePart
         {
             folderStream.Skip(skipSize);
         }
-        return new ReadOnlySubStream(folderStream, Header.Size);
+        return new ReadOnlySubStream(folderStream, Header.Size, leaveOpen: false);
     }
 
     public CompressionType CompressionType

src/SharpCompress/Common/Tar/Headers/TarHeader.cs

@@ -11,7 +11,7 @@ internal sealed class TarHeader
     internal static readonly DateTime EPOCH = new(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
 
     public TarHeader(
-        ArchiveEncoding archiveEncoding,
+        IArchiveEncoding archiveEncoding,
         TarHeaderWriteFormat writeFormat = TarHeaderWriteFormat.GNU_TAR_LONG_LINK
     )
     {
@@ -30,7 +30,7 @@ internal sealed class TarHeader
     internal DateTime LastModifiedTime { get; set; }
     internal EntryType EntryType { get; set; }
     internal Stream? PackedStream { get; set; }
-    internal ArchiveEncoding ArchiveEncoding { get; }
+    internal IArchiveEncoding ArchiveEncoding { get; }
 
     internal const int BLOCK_SIZE = 512;
 

src/SharpCompress/Common/Tar/TarEntry.cs

@@ -54,7 +54,7 @@ public class TarEntry : Entry
         StreamingMode mode,
         Stream stream,
         CompressionType compressionType,
-        ArchiveEncoding archiveEncoding
+        IArchiveEncoding archiveEncoding
     )
     {
         foreach (var header in TarHeaderFactory.ReadHeader(mode, stream, archiveEncoding))

src/SharpCompress/Common/Tar/TarHeaderFactory.cs

@@ -10,7 +10,7 @@ internal static class TarHeaderFactory
     internal static IEnumerable<TarHeader?> ReadHeader(
         StreamingMode mode,
         Stream stream,
-        ArchiveEncoding archiveEncoding
+        IArchiveEncoding archiveEncoding
     )
     {
         while (true)

src/SharpCompress/Common/Zip/Headers/DirectoryEndHeader.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
@@ -19,6 +20,18 @@ internal class DirectoryEndHeader : ZipHeader
         Comment = reader.ReadBytes(CommentLength);
     }
 
+    internal override async ValueTask Read(AsyncBinaryReader reader)
+    {
+        VolumeNumber = await reader.ReadUInt16Async();
+        FirstVolumeWithDirectory = await reader.ReadUInt16Async();
+        TotalNumberOfEntriesInDisk = await reader.ReadUInt16Async();
+        TotalNumberOfEntries = await reader.ReadUInt16Async();
+        DirectorySize = await reader.ReadUInt32Async();
+        DirectoryStartOffsetRelativeToDisk = await reader.ReadUInt32Async();
+        CommentLength = await reader.ReadUInt16Async();
+        Comment = await reader.ReadBytesAsync(CommentLength);
+    }
+
     public ushort VolumeNumber { get; private set; }
 
     public ushort FirstVolumeWithDirectory { get; private set; }

src/SharpCompress/Common/Zip/Headers/DirectoryEntryHeader.cs

@@ -1,11 +1,12 @@
 using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
 internal class DirectoryEntryHeader : ZipFileEntry
 {
-    public DirectoryEntryHeader(ArchiveEncoding archiveEncoding)
+    public DirectoryEntryHeader(IArchiveEncoding archiveEncoding)
         : base(ZipHeaderType.DirectoryEntry, archiveEncoding) { }
 
     internal override void Read(BinaryReader reader)
@@ -31,7 +32,37 @@ internal class DirectoryEntryHeader : ZipFileEntry
         var extra = reader.ReadBytes(extraLength);
         var comment = reader.ReadBytes(commentLength);
 
-        // According to .ZIP File Format Specification
+        ProcessReadData(name, extra, comment);
+    }
+
+    internal override async ValueTask Read(AsyncBinaryReader reader)
+    {
+        Version = await reader.ReadUInt16Async();
+        VersionNeededToExtract = await reader.ReadUInt16Async();
+        Flags = (HeaderFlags)await reader.ReadUInt16Async();
+        CompressionMethod = (ZipCompressionMethod)await reader.ReadUInt16Async();
+        OriginalLastModifiedTime = LastModifiedTime = await reader.ReadUInt16Async();
+        OriginalLastModifiedDate = LastModifiedDate = await reader.ReadUInt16Async();
+        Crc = await reader.ReadUInt32Async();
+        CompressedSize = await reader.ReadUInt32Async();
+        UncompressedSize = await reader.ReadUInt32Async();
+        var nameLength = await reader.ReadUInt16Async();
+        var extraLength = await reader.ReadUInt16Async();
+        var commentLength = await reader.ReadUInt16Async();
+        DiskNumberStart = await reader.ReadUInt16Async();
+        InternalFileAttributes = await reader.ReadUInt16Async();
+        ExternalFileAttributes = await reader.ReadUInt32Async();
+        RelativeOffsetOfEntryHeader = await reader.ReadUInt32Async();
+
+        var name = await reader.ReadBytesAsync(nameLength);
+        var extra = await reader.ReadBytesAsync(extraLength);
+        var comment = await reader.ReadBytesAsync(commentLength);
+
+        ProcessReadData(name, extra, comment);
+    }
+
+    private void ProcessReadData(byte[] name, byte[] extra, byte[] comment)
+    {
         //
         // For example: https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT
         //
@@ -41,8 +72,8 @@ internal class DirectoryEntryHeader : ZipFileEntry
 
         if (Flags.HasFlag(HeaderFlags.Efs))
         {
-            Name = ArchiveEncoding.DecodeUTF8(name);
-            Comment = ArchiveEncoding.DecodeUTF8(comment);
+            Name = ArchiveEncoding.Decode(name, EncodingType.UTF8);
+            Comment = ArchiveEncoding.Decode(comment, EncodingType.UTF8);
         }
         else
         {

src/SharpCompress/Common/Zip/Headers/IgnoreHeader.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
@@ -8,4 +9,6 @@ internal class IgnoreHeader : ZipHeader
         : base(type) { }
 
     internal override void Read(BinaryReader reader) { }
+
+    internal override ValueTask Read(AsyncBinaryReader reader) => default;
 }

src/SharpCompress/Common/Zip/Headers/LocalEntryHeader.cs

@@ -1,13 +1,12 @@
 using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
-internal class LocalEntryHeader : ZipFileEntry
+internal class LocalEntryHeader(IArchiveEncoding archiveEncoding)
+    : ZipFileEntry(ZipHeaderType.LocalEntry, archiveEncoding)
 {
-    public LocalEntryHeader(ArchiveEncoding archiveEncoding)
-        : base(ZipHeaderType.LocalEntry, archiveEncoding) { }
-
     internal override void Read(BinaryReader reader)
     {
         Version = reader.ReadUInt16();
@@ -23,7 +22,29 @@ internal class LocalEntryHeader : ZipFileEntry
         var name = reader.ReadBytes(nameLength);
         var extra = reader.ReadBytes(extraLength);
 
-        // According to .ZIP File Format Specification
+        ProcessReadData(name, extra);
+    }
+
+    internal override async ValueTask Read(AsyncBinaryReader reader)
+    {
+        Version = await reader.ReadUInt16Async();
+        Flags = (HeaderFlags)await reader.ReadUInt16Async();
+        CompressionMethod = (ZipCompressionMethod)await reader.ReadUInt16Async();
+        OriginalLastModifiedTime = LastModifiedTime = await reader.ReadUInt16Async();
+        OriginalLastModifiedDate = LastModifiedDate = await reader.ReadUInt16Async();
+        Crc = await reader.ReadUInt32Async();
+        CompressedSize = await reader.ReadUInt32Async();
+        UncompressedSize = await reader.ReadUInt32Async();
+        var nameLength = await reader.ReadUInt16Async();
+        var extraLength = await reader.ReadUInt16Async();
+        var name = await reader.ReadBytesAsync(nameLength);
+        var extra = await reader.ReadBytesAsync(extraLength);
+
+        ProcessReadData(name, extra);
+    }
+
+    private void ProcessReadData(byte[] name, byte[] extra)
+    {
         //
         // For example: https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT
         //
@@ -33,7 +54,7 @@ internal class LocalEntryHeader : ZipFileEntry
 
         if (Flags.HasFlag(HeaderFlags.Efs))
         {
-            Name = ArchiveEncoding.DecodeUTF8(name);
+            Name = ArchiveEncoding.Decode(name, EncodingType.UTF8);
         }
         else
         {

src/SharpCompress/Common/Zip/Headers/LocalEntryHeaderExtraFactory.cs

@@ -15,10 +15,6 @@ internal enum ExtraDataType : ushort
     UnicodePathExtraField = 0x7075,
     Zip64ExtendedInformationExtraField = 0x0001,
     UnixTimeExtraField = 0x5455,
-
-    // SOZip (Seek-Optimized ZIP) extra field
-    // Used to link a main file to its SOZip index file
-    SOZip = 0x564B,
 }
 
 internal class ExtraData
@@ -237,44 +233,6 @@ internal sealed class UnixTimeExtraField : ExtraData
     }
 }
 
-/// <summary>
-/// SOZip (Seek-Optimized ZIP) extra field that links a main file to its index file.
-/// The extra field contains the offset within the ZIP file where the index entry's
-/// local header is located.
-/// </summary>
-internal sealed class SOZipExtraField : ExtraData
-{
-    public SOZipExtraField(ExtraDataType type, ushort length, byte[] dataBytes)
-        : base(type, length, dataBytes) { }
-
-    /// <summary>
-    /// Gets the offset to the SOZip index file's local entry header within the ZIP archive.
-    /// </summary>
-    internal ulong IndexOffset
-    {
-        get
-        {
-            if (DataBytes is null || DataBytes.Length < 8)
-            {
-                return 0;
-            }
-            return BinaryPrimitives.ReadUInt64LittleEndian(DataBytes);
-        }
-    }
-
-    /// <summary>
-    /// Creates a SOZip extra field with the specified index offset
-    /// </summary>
-    /// <param name="indexOffset">The offset to the index file's local entry header</param>
-    /// <returns>A new SOZipExtraField instance</returns>
-    public static SOZipExtraField Create(ulong indexOffset)
-    {
-        var data = new byte[8];
-        BinaryPrimitives.WriteUInt64LittleEndian(data, indexOffset);
-        return new SOZipExtraField(ExtraDataType.SOZip, 8, data);
-    }
-}
-
 internal static class LocalEntryHeaderExtraFactory
 {
     internal static ExtraData Create(ExtraDataType type, ushort length, byte[] extraData) =>
@@ -288,7 +246,6 @@ internal static class LocalEntryHeaderExtraFactory
             ExtraDataType.Zip64ExtendedInformationExtraField =>
                 new Zip64ExtendedInformationExtraField(type, length, extraData),
             ExtraDataType.UnixTimeExtraField => new UnixTimeExtraField(type, length, extraData),
-            ExtraDataType.SOZip => new SOZipExtraField(type, length, extraData),
             _ => new ExtraData(type, length, extraData),
         };
 }

src/SharpCompress/Common/Zip/Headers/SplitHeader.cs

@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
@@ -9,4 +10,7 @@ internal class SplitHeader : ZipHeader
         : base(ZipHeaderType.Split) { }
 
     internal override void Read(BinaryReader reader) => throw new NotImplementedException();
+
+    internal override ValueTask Read(AsyncBinaryReader reader) =>
+        throw new NotImplementedException();
 }

src/SharpCompress/Common/Zip/Headers/Zip64DirectoryEndHeader.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
@@ -26,6 +27,25 @@ internal class Zip64DirectoryEndHeader : ZipHeader
         );
     }
 
+    internal override async ValueTask Read(AsyncBinaryReader reader)
+    {
+        SizeOfDirectoryEndRecord = (long)await reader.ReadUInt64Async();
+        VersionMadeBy = await reader.ReadUInt16Async();
+        VersionNeededToExtract = await reader.ReadUInt16Async();
+        VolumeNumber = await reader.ReadUInt32Async();
+        FirstVolumeWithDirectory = await reader.ReadUInt32Async();
+        TotalNumberOfEntriesInDisk = (long)await reader.ReadUInt64Async();
+        TotalNumberOfEntries = (long)await reader.ReadUInt64Async();
+        DirectorySize = (long)await reader.ReadUInt64Async();
+        DirectoryStartOffsetRelativeToDisk = (long)await reader.ReadUInt64Async();
+        DataSector = await reader.ReadBytesAsync(
+            (int)(
+                SizeOfDirectoryEndRecord
+                - SIZE_OF_FIXED_HEADER_DATA_EXCEPT_SIGNATURE_AND_SIZE_FIELDS
+            )
+        );
+    }
+
     private const int SIZE_OF_FIXED_HEADER_DATA_EXCEPT_SIGNATURE_AND_SIZE_FIELDS = 44;
 
     public long SizeOfDirectoryEndRecord { get; private set; }

src/SharpCompress/Common/Zip/Headers/Zip64DirectoryEndLocatorHeader.cs

@@ -1,12 +1,10 @@
 using System.IO;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
-internal class Zip64DirectoryEndLocatorHeader : ZipHeader
+internal class Zip64DirectoryEndLocatorHeader() : ZipHeader(ZipHeaderType.Zip64DirectoryEndLocator)
 {
-    public Zip64DirectoryEndLocatorHeader()
-        : base(ZipHeaderType.Zip64DirectoryEndLocator) { }
-
     internal override void Read(BinaryReader reader)
     {
         FirstVolumeWithDirectory = reader.ReadUInt32();
@@ -14,6 +12,13 @@ internal class Zip64DirectoryEndLocatorHeader : ZipHeader
         TotalNumberOfVolumes = reader.ReadUInt32();
     }
 
+    internal override async ValueTask Read(AsyncBinaryReader reader)
+    {
+        FirstVolumeWithDirectory = await reader.ReadUInt32Async();
+        RelativeOffsetOfTheEndOfDirectoryRecord = (long)await reader.ReadUInt64Async();
+        TotalNumberOfVolumes = await reader.ReadUInt32Async();
+    }
+
     public uint FirstVolumeWithDirectory { get; private set; }
 
     public long RelativeOffsetOfTheEndOfDirectoryRecord { get; private set; }

src/SharpCompress/Common/Zip/Headers/ZipFileEntry.cs

@@ -2,18 +2,14 @@ using System;
 using System.Buffers.Binary;
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
-internal abstract class ZipFileEntry : ZipHeader
+internal abstract class ZipFileEntry(ZipHeaderType type, IArchiveEncoding archiveEncoding)
+    : ZipHeader(type)
 {
-    protected ZipFileEntry(ZipHeaderType type, ArchiveEncoding archiveEncoding)
-        : base(type)
-    {
-        Extra = new List<ExtraData>();
-        ArchiveEncoding = archiveEncoding;
-    }
-
     internal bool IsDirectory
     {
         get
@@ -30,7 +26,7 @@ internal abstract class ZipFileEntry : ZipHeader
 
     internal Stream? PackedStream { get; set; }
 
-    internal ArchiveEncoding ArchiveEncoding { get; }
+    internal IArchiveEncoding ArchiveEncoding { get; } = archiveEncoding;
 
     internal string? Name { get; set; }
 
@@ -44,7 +40,7 @@ internal abstract class ZipFileEntry : ZipHeader
 
     internal long UncompressedSize { get; set; }
 
-    internal List<ExtraData> Extra { get; set; }
+    internal List<ExtraData> Extra { get; set; } = new();
 
     public string? Password { get; set; }
 
@@ -63,6 +59,24 @@ internal abstract class ZipFileEntry : ZipHeader
         return encryptionData;
     }
 
+    internal async ValueTask<PkwareTraditionalEncryptionData> ComposeEncryptionDataAsync(
+        Stream archiveStream,
+        CancellationToken cancellationToken = default
+    )
+    {
+        if (archiveStream is null)
+        {
+            throw new ArgumentNullException(nameof(archiveStream));
+        }
+
+        var buffer = new byte[12];
+        await archiveStream.ReadFullyAsync(buffer, 0, 12, cancellationToken).ConfigureAwait(false);
+
+        var encryptionData = PkwareTraditionalEncryptionData.ForRead(Password!, this, buffer);
+
+        return encryptionData;
+    }
+
     internal WinzipAesEncryptionData? WinzipAesEncryptionData { get; set; }
 
     /// <summary>

src/SharpCompress/Common/Zip/Headers/ZipHeader.cs

@@ -1,18 +1,14 @@
 using System.IO;
+using System.Threading.Tasks;
 
 namespace SharpCompress.Common.Zip.Headers;
 
-internal abstract class ZipHeader
+internal abstract class ZipHeader(ZipHeaderType type)
 {
-    protected ZipHeader(ZipHeaderType type)
-    {
-        ZipHeaderType = type;
-        HasData = true;
-    }
-
-    internal ZipHeaderType ZipHeaderType { get; }
+    internal ZipHeaderType ZipHeaderType { get; } = type;
 
     internal abstract void Read(BinaryReader reader);
+    internal abstract ValueTask Read(AsyncBinaryReader reader);
 
-    internal bool HasData { get; set; }
+    internal bool HasData { get; set; } = true;
 }

src/SharpCompress/Common/Zip/PkwareTraditionalEncryptionData.cs

@@ -8,9 +8,9 @@ internal class PkwareTraditionalEncryptionData
 {
     private static readonly CRC32 CRC32 = new();
     private readonly uint[] _keys = { 0x12345678, 0x23456789, 0x34567890 };
-    private readonly ArchiveEncoding _archiveEncoding;
+    private readonly IArchiveEncoding _archiveEncoding;
 
-    private PkwareTraditionalEncryptionData(string password, ArchiveEncoding archiveEncoding)
+    private PkwareTraditionalEncryptionData(string password, IArchiveEncoding archiveEncoding)
     {
         _archiveEncoding = archiveEncoding;
         Initialize(password);
@@ -103,7 +103,7 @@ internal class PkwareTraditionalEncryptionData
 
     internal byte[] StringToByteArray(string value)
     {
-        var a = _archiveEncoding.GetPasswordEncoding().GetBytes(value);
+        var a = _archiveEncoding.Password.GetBytes(value);
         return a;
     }
 

src/SharpCompress/Common/Zip/SOZip/SOZipDeflateStream.cs

@@ -1,150 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using SharpCompress.Compressors;
-using SharpCompress.Compressors.Deflate;
-
-namespace SharpCompress.Common.Zip.SOZip;
-
-/// <summary>
-/// A Deflate stream that inserts sync flush points at regular intervals
-/// to enable random access (SOZip optimization).
-/// </summary>
-internal sealed class SOZipDeflateStream : Stream
-{
-    private readonly DeflateStream _deflateStream;
-    private readonly Stream _baseStream;
-    private readonly uint _chunkSize;
-    private readonly List<ulong> _compressedOffsets = new();
-    private readonly long _baseOffset;
-    private long _uncompressedBytesWritten;
-    private long _nextSyncPoint;
-    private bool _disposed;
-
-    /// <summary>
-    /// Creates a new SOZip Deflate stream
-    /// </summary>
-    /// <param name="baseStream">The underlying stream to write to</param>
-    /// <param name="compressionLevel">The compression level</param>
-    /// <param name="chunkSize">The chunk size for sync flush points</param>
-    public SOZipDeflateStream(Stream baseStream, CompressionLevel compressionLevel, int chunkSize)
-    {
-        _baseStream = baseStream;
-        _chunkSize = (uint)chunkSize;
-        _baseOffset = baseStream.Position;
-        _nextSyncPoint = chunkSize;
-
-        // Record the first offset (start of compressed data)
-        _compressedOffsets.Add(0);
-
-        _deflateStream = new DeflateStream(baseStream, CompressionMode.Compress, compressionLevel);
-    }
-
-    /// <summary>
-    /// Gets the array of compressed offsets recorded during writing
-    /// </summary>
-    public ulong[] CompressedOffsets => _compressedOffsets.ToArray();
-
-    /// <summary>
-    /// Gets the total number of uncompressed bytes written
-    /// </summary>
-    public ulong UncompressedBytesWritten => (ulong)_uncompressedBytesWritten;
-
-    /// <summary>
-    /// Gets the total number of compressed bytes written
-    /// </summary>
-    public ulong CompressedBytesWritten => (ulong)(_baseStream.Position - _baseOffset);
-
-    /// <summary>
-    /// Gets the chunk size being used
-    /// </summary>
-    public uint ChunkSize => _chunkSize;
-
-    public override bool CanRead => false;
-
-    public override bool CanSeek => false;
-
-    public override bool CanWrite => !_disposed && _deflateStream.CanWrite;
-
-    public override long Length => throw new NotSupportedException();
-
-    public override long Position
-    {
-        get => throw new NotSupportedException();
-        set => throw new NotSupportedException();
-    }
-
-    public override void Flush() => _deflateStream.Flush();
-
-    public override int Read(byte[] buffer, int offset, int count) =>
-        throw new NotSupportedException();
-
-    public override long Seek(long offset, SeekOrigin origin) => throw new NotSupportedException();
-
-    public override void SetLength(long value) => throw new NotSupportedException();
-
-    public override void Write(byte[] buffer, int offset, int count)
-    {
-        if (_disposed)
-        {
-            throw new ObjectDisposedException(nameof(SOZipDeflateStream));
-        }
-
-        var remaining = count;
-        var currentOffset = offset;
-
-        while (remaining > 0)
-        {
-            // Calculate how many bytes until the next sync point
-            var bytesUntilSync = (int)(_nextSyncPoint - _uncompressedBytesWritten);
-
-            if (bytesUntilSync <= 0)
-            {
-                // We've reached a sync point - perform sync flush
-                PerformSyncFlush();
-                continue;
-            }
-
-            // Write up to the next sync point
-            var bytesToWrite = Math.Min(remaining, bytesUntilSync);
-            _deflateStream.Write(buffer, currentOffset, bytesToWrite);
-
-            _uncompressedBytesWritten += bytesToWrite;
-            currentOffset += bytesToWrite;
-            remaining -= bytesToWrite;
-        }
-    }
-
-    private void PerformSyncFlush()
-    {
-        // Flush with Z_SYNC_FLUSH to create an independent block
-        var originalFlushMode = _deflateStream.FlushMode;
-        _deflateStream.FlushMode = FlushType.Sync;
-        _deflateStream.Flush();
-        _deflateStream.FlushMode = originalFlushMode;
-
-        // Record the compressed offset for this sync point
-        var compressedOffset = (ulong)(_baseStream.Position - _baseOffset);
-        _compressedOffsets.Add(compressedOffset);
-
-        // Set the next sync point
-        _nextSyncPoint += _chunkSize;
-    }
-
-    protected override void Dispose(bool disposing)
-    {
-        if (_disposed)
-        {
-            return;
-        }
-
-        _disposed = true;
-
-        if (disposing)
-        {
-            _deflateStream.Dispose();
-        }
-
-        base.Dispose(disposing);
-    }
-}

src/SharpCompress/Common/Zip/SOZip/SOZipIndex.cs

@@ -1,367 +0,0 @@
-using System;
-using System.Buffers.Binary;
-using System.IO;
-
-namespace SharpCompress.Common.Zip.SOZip;
-
-/// <summary>
-/// Represents a SOZip (Seek-Optimized ZIP) index that enables random access
-/// within DEFLATE-compressed files by storing offsets to sync flush points.
-/// </summary>
-/// <remarks>
-/// SOZip index files (.sozip.idx) contain a header followed by offset entries
-/// that point to the beginning of independently decompressable DEFLATE blocks.
-/// </remarks>
-[CLSCompliant(false)]
-public sealed class SOZipIndex
-{
-    /// <summary>
-    /// SOZip index file magic number: "SOZo" (0x534F5A6F)
-    /// </summary>
-    public const uint SOZIP_MAGIC = 0x6F5A4F53; // "SOZo" little-endian
-
-    /// <summary>
-    /// Current SOZip specification version
-    /// </summary>
-    public const byte SOZIP_VERSION = 1;
-
-    /// <summary>
-    /// Index file extension suffix
-    /// </summary>
-    public const string INDEX_EXTENSION = ".sozip.idx";
-
-    /// <summary>
-    /// Default chunk size in bytes (32KB)
-    /// </summary>
-    public const uint DEFAULT_CHUNK_SIZE = 32768;
-
-    /// <summary>
-    /// The version of the SOZip index format
-    /// </summary>
-    public byte Version { get; private set; }
-
-    /// <summary>
-    /// Size of each uncompressed chunk in bytes
-    /// </summary>
-    public uint ChunkSize { get; private set; }
-
-    /// <summary>
-    /// Total uncompressed size of the file
-    /// </summary>
-    public ulong UncompressedSize { get; private set; }
-
-    /// <summary>
-    /// Total compressed size of the file
-    /// </summary>
-    public ulong CompressedSize { get; private set; }
-
-    /// <summary>
-    /// Number of offset entries in the index
-    /// </summary>
-    public uint OffsetCount { get; private set; }
-
-    /// <summary>
-    /// Array of compressed offsets for each chunk
-    /// </summary>
-    public ulong[] CompressedOffsets { get; private set; } = Array.Empty<ulong>();
-
-    /// <summary>
-    /// Creates a new empty SOZip index
-    /// </summary>
-    public SOZipIndex() { }
-
-    /// <summary>
-    /// Creates a new SOZip index with specified parameters
-    /// </summary>
-    /// <param name="chunkSize">Size of each uncompressed chunk</param>
-    /// <param name="uncompressedSize">Total uncompressed size</param>
-    /// <param name="compressedSize">Total compressed size</param>
-    /// <param name="compressedOffsets">Array of compressed offsets</param>
-    public SOZipIndex(
-        uint chunkSize,
-        ulong uncompressedSize,
-        ulong compressedSize,
-        ulong[] compressedOffsets
-    )
-    {
-        Version = SOZIP_VERSION;
-        ChunkSize = chunkSize;
-        UncompressedSize = uncompressedSize;
-        CompressedSize = compressedSize;
-        OffsetCount = (uint)compressedOffsets.Length;
-        CompressedOffsets = compressedOffsets;
-    }
-
-    /// <summary>
-    /// Reads a SOZip index from a stream
-    /// </summary>
-    /// <param name="stream">The stream containing the index data</param>
-    /// <returns>A parsed SOZipIndex instance</returns>
-    /// <exception cref="InvalidDataException">If the stream doesn't contain valid SOZip index data</exception>
-    public static SOZipIndex Read(Stream stream)
-    {
-        var index = new SOZipIndex();
-        Span<byte> header = stackalloc byte[4];
-
-        // Read magic number
-        if (stream.Read(header) != 4)
-        {
-            throw new InvalidDataException("Invalid SOZip index: unable to read magic number");
-        }
-
-        var magic = BinaryPrimitives.ReadUInt32LittleEndian(header);
-        if (magic != SOZIP_MAGIC)
-        {
-            throw new InvalidDataException(
-                $"Invalid SOZip index: magic number mismatch (expected 0x{SOZIP_MAGIC:X8}, got 0x{magic:X8})"
-            );
-        }
-
-        // Read version
-        var versionByte = stream.ReadByte();
-        if (versionByte < 0)
-        {
-            throw new InvalidDataException("Invalid SOZip index: unable to read version");
-        }
-        index.Version = (byte)versionByte;
-
-        if (index.Version != SOZIP_VERSION)
-        {
-            throw new InvalidDataException(
-                $"Unsupported SOZip index version: {index.Version} (expected {SOZIP_VERSION})"
-            );
-        }
-
-        // Read reserved byte (padding)
-        stream.ReadByte();
-
-        // Read chunk size (2 bytes)
-        Span<byte> buf2 = stackalloc byte[2];
-        if (stream.Read(buf2) != 2)
-        {
-            throw new InvalidDataException("Invalid SOZip index: unable to read chunk size");
-        }
-
-        // Chunk size is stored as (actual_size / 1024) - 1
-        var chunkSizeEncoded = BinaryPrimitives.ReadUInt16LittleEndian(buf2);
-        index.ChunkSize = ((uint)chunkSizeEncoded + 1) * 1024;
-
-        // Read uncompressed size (8 bytes)
-        Span<byte> buf8 = stackalloc byte[8];
-        if (stream.Read(buf8) != 8)
-        {
-            throw new InvalidDataException("Invalid SOZip index: unable to read uncompressed size");
-        }
-        index.UncompressedSize = BinaryPrimitives.ReadUInt64LittleEndian(buf8);
-
-        // Read compressed size (8 bytes)
-        if (stream.Read(buf8) != 8)
-        {
-            throw new InvalidDataException("Invalid SOZip index: unable to read compressed size");
-        }
-        index.CompressedSize = BinaryPrimitives.ReadUInt64LittleEndian(buf8);
-
-        // Read offset count (4 bytes)
-        if (stream.Read(header) != 4)
-        {
-            throw new InvalidDataException("Invalid SOZip index: unable to read offset count");
-        }
-        index.OffsetCount = BinaryPrimitives.ReadUInt32LittleEndian(header);
-
-        // Read offsets
-        index.CompressedOffsets = new ulong[index.OffsetCount];
-        for (uint i = 0; i < index.OffsetCount; i++)
-        {
-            if (stream.Read(buf8) != 8)
-            {
-                throw new InvalidDataException($"Invalid SOZip index: unable to read offset {i}");
-            }
-            index.CompressedOffsets[i] = BinaryPrimitives.ReadUInt64LittleEndian(buf8);
-        }
-
-        return index;
-    }
-
-    /// <summary>
-    /// Reads a SOZip index from a byte array
-    /// </summary>
-    /// <param name="data">The byte array containing the index data</param>
-    /// <returns>A parsed SOZipIndex instance</returns>
-    public static SOZipIndex Read(byte[] data)
-    {
-        using var stream = new MemoryStream(data);
-        return Read(stream);
-    }
-
-    /// <summary>
-    /// Writes this SOZip index to a stream
-    /// </summary>
-    /// <param name="stream">The stream to write to</param>
-    public void Write(Stream stream)
-    {
-        Span<byte> buf8 = stackalloc byte[8];
-
-        // Write magic number
-        BinaryPrimitives.WriteUInt32LittleEndian(buf8, SOZIP_MAGIC);
-        stream.Write(buf8.Slice(0, 4));
-
-        // Write version
-        stream.WriteByte(SOZIP_VERSION);
-
-        // Write reserved byte (padding)
-        stream.WriteByte(0);
-
-        // Write chunk size (encoded as (size/1024)-1)
-        var chunkSizeEncoded = (ushort)((ChunkSize / 1024) - 1);
-        BinaryPrimitives.WriteUInt16LittleEndian(buf8, chunkSizeEncoded);
-        stream.Write(buf8.Slice(0, 2));
-
-        // Write uncompressed size
-        BinaryPrimitives.WriteUInt64LittleEndian(buf8, UncompressedSize);
-        stream.Write(buf8);
-
-        // Write compressed size
-        BinaryPrimitives.WriteUInt64LittleEndian(buf8, CompressedSize);
-        stream.Write(buf8);
-
-        // Write offset count
-        BinaryPrimitives.WriteUInt32LittleEndian(buf8, OffsetCount);
-        stream.Write(buf8.Slice(0, 4));
-
-        // Write offsets
-        foreach (var offset in CompressedOffsets)
-        {
-            BinaryPrimitives.WriteUInt64LittleEndian(buf8, offset);
-            stream.Write(buf8);
-        }
-    }
-
-    /// <summary>
-    /// Converts this SOZip index to a byte array
-    /// </summary>
-    /// <returns>Byte array containing the serialized index</returns>
-    public byte[] ToByteArray()
-    {
-        using var stream = new MemoryStream();
-        Write(stream);
-        return stream.ToArray();
-    }
-
-    /// <summary>
-    /// Gets the index of the chunk that contains the specified uncompressed offset
-    /// </summary>
-    /// <param name="uncompressedOffset">The uncompressed byte offset</param>
-    /// <returns>The chunk index</returns>
-    public int GetChunkIndex(long uncompressedOffset)
-    {
-        if (uncompressedOffset < 0 || (ulong)uncompressedOffset >= UncompressedSize)
-        {
-            throw new ArgumentOutOfRangeException(
-                nameof(uncompressedOffset),
-                "Offset is out of range"
-            );
-        }
-
-        return (int)((ulong)uncompressedOffset / ChunkSize);
-    }
-
-    /// <summary>
-    /// Gets the compressed offset for the specified chunk index
-    /// </summary>
-    /// <param name="chunkIndex">The chunk index</param>
-    /// <returns>The compressed byte offset for the start of the chunk</returns>
-    public ulong GetCompressedOffset(int chunkIndex)
-    {
-        if (chunkIndex < 0 || chunkIndex >= CompressedOffsets.Length)
-        {
-            throw new ArgumentOutOfRangeException(
-                nameof(chunkIndex),
-                "Chunk index is out of range"
-            );
-        }
-
-        return CompressedOffsets[chunkIndex];
-    }
-
-    /// <summary>
-    /// Gets the uncompressed offset for the start of the specified chunk
-    /// </summary>
-    /// <param name="chunkIndex">The chunk index</param>
-    /// <returns>The uncompressed byte offset for the start of the chunk</returns>
-    public ulong GetUncompressedOffset(int chunkIndex)
-    {
-        if (chunkIndex < 0 || chunkIndex >= CompressedOffsets.Length)
-        {
-            throw new ArgumentOutOfRangeException(
-                nameof(chunkIndex),
-                "Chunk index is out of range"
-            );
-        }
-
-        return (ulong)chunkIndex * ChunkSize;
-    }
-
-    /// <summary>
-    /// Gets the name of the SOZip index file for a given entry name
-    /// </summary>
-    /// <param name="entryName">The main entry name</param>
-    /// <returns>The index file name (hidden with .sozip.idx extension)</returns>
-    public static string GetIndexFileName(string entryName)
-    {
-        var directory = Path.GetDirectoryName(entryName);
-        var fileName = Path.GetFileName(entryName);
-
-        // The index file is hidden (prefixed with .)
-        var indexFileName = $".{fileName}{INDEX_EXTENSION}";
-
-        if (string.IsNullOrEmpty(directory))
-        {
-            return indexFileName;
-        }
-
-        return Path.Combine(directory, indexFileName).Replace('\\', '/');
-    }
-
-    /// <summary>
-    /// Checks if a file name is a SOZip index file
-    /// </summary>
-    /// <param name="fileName">The file name to check</param>
-    /// <returns>True if the file is a SOZip index file</returns>
-    public static bool IsIndexFile(string fileName)
-    {
-        if (string.IsNullOrEmpty(fileName))
-        {
-            return false;
-        }
-
-        var name = Path.GetFileName(fileName);
-        return name.StartsWith(".", StringComparison.Ordinal)
-            && name.EndsWith(INDEX_EXTENSION, StringComparison.OrdinalIgnoreCase);
-    }
-
-    /// <summary>
-    /// Gets the main file name from a SOZip index file name
-    /// </summary>
-    /// <param name="indexFileName">The index file name</param>
-    /// <returns>The main file name, or null if not a valid index file</returns>
-    public static string? GetMainFileName(string indexFileName)
-    {
-        if (!IsIndexFile(indexFileName))
-        {
-            return null;
-        }
-
-        var directory = Path.GetDirectoryName(indexFileName);
-        var name = Path.GetFileName(indexFileName);
-
-        // Remove leading '.' and trailing '.sozip.idx'
-        var mainName = name.Substring(1, name.Length - 1 - INDEX_EXTENSION.Length);
-
-        if (string.IsNullOrEmpty(directory))
-        {
-            return mainName;
-        }
-
-        return Path.Combine(directory, mainName).Replace('\\', '/');
-    }
-}

src/SharpCompress/Common/Zip/SeekableZipFilePart.cs

@@ -1,4 +1,6 @@
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common.Zip.Headers;
 
 namespace SharpCompress.Common.Zip;
@@ -25,9 +27,24 @@ internal class SeekableZipFilePart : ZipFilePart
         return base.GetCompressedStream();
     }
 
+    internal override async ValueTask<Stream?> GetCompressedStreamAsync(
+        CancellationToken cancellationToken = default
+    )
+    {
+        if (!_isLocalHeaderLoaded)
+        {
+            await LoadLocalHeaderAsync(cancellationToken);
+            _isLocalHeaderLoaded = true;
+        }
+        return await base.GetCompressedStreamAsync(cancellationToken);
+    }
+
     private void LoadLocalHeader() =>
         Header = _headerFactory.GetLocalHeader(BaseStream, (DirectoryEntryHeader)Header);
 
+    private async ValueTask LoadLocalHeaderAsync(CancellationToken cancellationToken = default) =>
+        Header = await _headerFactory.GetLocalHeaderAsync(BaseStream, (DirectoryEntryHeader)Header);
+
     protected override Stream CreateBaseStream()
     {
         BaseStream.Position = Header.DataStartPosition.NotNull();

src/SharpCompress/Common/Zip/SeekableZipHeaderFactory.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Threading.Tasks;
 using SharpCompress.Common.Zip.Headers;
 using SharpCompress.IO;
 
@@ -15,10 +16,77 @@ internal sealed class SeekableZipHeaderFactory : ZipHeaderFactory
     private const int MAX_SEARCH_LENGTH_FOR_EOCD = 65557;
     private bool _zip64;
 
-    internal SeekableZipHeaderFactory(string? password, ArchiveEncoding archiveEncoding)
+    internal SeekableZipHeaderFactory(string? password, IArchiveEncoding archiveEncoding)
         : base(StreamingMode.Seekable, password, archiveEncoding) { }
 
-    internal IEnumerable<ZipHeader> ReadSeekableHeader(Stream stream)
+    internal async IAsyncEnumerable<ZipHeader> ReadSeekableHeaderAsync(Stream stream)
+    {
+        var reader = new AsyncBinaryReader(stream);
+
+        await SeekBackToHeaderAsync(stream, reader);
+
+        var eocd_location = stream.Position;
+        var entry = new DirectoryEndHeader();
+        await entry.Read(reader);
+
+        if (entry.IsZip64)
+        {
+            _zip64 = true;
+
+            // ZIP64_END_OF_CENTRAL_DIRECTORY_LOCATOR should be before the EOCD
+            stream.Seek(eocd_location - ZIP64_EOCD_LENGTH - 4, SeekOrigin.Begin);
+            uint zip64_locator = await reader.ReadUInt32Async();
+            if (zip64_locator != ZIP64_END_OF_CENTRAL_DIRECTORY_LOCATOR)
+            {
+                throw new ArchiveException("Failed to locate the Zip64 Directory Locator");
+            }
+
+            var zip64Locator = new Zip64DirectoryEndLocatorHeader();
+            await zip64Locator.Read(reader);
+
+            stream.Seek(zip64Locator.RelativeOffsetOfTheEndOfDirectoryRecord, SeekOrigin.Begin);
+            var zip64Signature = await reader.ReadUInt32Async();
+            if (zip64Signature != ZIP64_END_OF_CENTRAL_DIRECTORY)
+            {
+                throw new ArchiveException("Failed to locate the Zip64 Header");
+            }
+
+            var zip64Entry = new Zip64DirectoryEndHeader();
+            await zip64Entry.Read(reader);
+            stream.Seek(zip64Entry.DirectoryStartOffsetRelativeToDisk, SeekOrigin.Begin);
+        }
+        else
+        {
+            stream.Seek(entry.DirectoryStartOffsetRelativeToDisk, SeekOrigin.Begin);
+        }
+
+        var position = stream.Position;
+        while (true)
+        {
+            stream.Position = position;
+            var signature = await reader.ReadUInt32Async();
+            var nextHeader = await ReadHeader(signature, reader, _zip64);
+            position = stream.Position;
+
+            if (nextHeader is null)
+            {
+                yield break;
+            }
+
+            if (nextHeader is DirectoryEntryHeader entryHeader)
+            {
+                //entry could be zero bytes so we need to know that.
+                entryHeader.HasData = entryHeader.CompressedSize != 0;
+                yield return entryHeader;
+            }
+            else if (nextHeader is DirectoryEndHeader endHeader)
+            {
+                yield return endHeader;
+            }
+        }
+    }
+
+    internal IEnumerable<ZipHeader> ReadSeekableHeader(Stream stream, bool useSync)
     {
         var reader = new BinaryReader(stream);
 
@@ -85,6 +153,73 @@ internal sealed class SeekableZipHeaderFactory : ZipHeaderFactory
         }
     }
 
+    internal async IAsyncEnumerable<ZipHeader> ReadSeekableHeaderAsync(Stream stream, bool useSync)
+    {
+        var reader = new AsyncBinaryReader(stream);
+
+        await SeekBackToHeaderAsync(stream, reader);
+
+        var eocd_location = stream.Position;
+        var entry = new DirectoryEndHeader();
+        await entry.Read(reader);
+
+        if (entry.IsZip64)
+        {
+            _zip64 = true;
+
+            // ZIP64_END_OF_CENTRAL_DIRECTORY_LOCATOR should be before the EOCD
+            stream.Seek(eocd_location - ZIP64_EOCD_LENGTH - 4, SeekOrigin.Begin);
+            var zip64_locator = await reader.ReadUInt32Async();
+            if (zip64_locator != ZIP64_END_OF_CENTRAL_DIRECTORY_LOCATOR)
+            {
+                throw new ArchiveException("Failed to locate the Zip64 Directory Locator");
+            }
+
+            var zip64Locator = new Zip64DirectoryEndLocatorHeader();
+            await zip64Locator.Read(reader);
+
+            stream.Seek(zip64Locator.RelativeOffsetOfTheEndOfDirectoryRecord, SeekOrigin.Begin);
+            var zip64Signature = await reader.ReadUInt32Async();
+            if (zip64Signature != ZIP64_END_OF_CENTRAL_DIRECTORY)
+            {
+                throw new ArchiveException("Failed to locate the Zip64 Header");
+            }
+
+            var zip64Entry = new Zip64DirectoryEndHeader();
+            await zip64Entry.Read(reader);
+            stream.Seek(zip64Entry.DirectoryStartOffsetRelativeToDisk, SeekOrigin.Begin);
+        }
+        else
+        {
+            stream.Seek(entry.DirectoryStartOffsetRelativeToDisk, SeekOrigin.Begin);
+        }
+
+        var position = stream.Position;
+        while (true)
+        {
+            stream.Position = position;
+            var signature = await reader.ReadUInt32Async();
+            var nextHeader = await ReadHeader(signature, reader, _zip64);
+            position = stream.Position;
+
+            if (nextHeader is null)
+            {
+                yield break;
+            }
+
+            if (nextHeader is DirectoryEntryHeader entryHeader)
+            {
+                //entry could be zero bytes so we need to know that.
+                entryHeader.HasData = entryHeader.CompressedSize != 0;
+                yield return entryHeader;
+            }
+            else if (nextHeader is DirectoryEndHeader endHeader)
+            {
+                yield return endHeader;
+            }
+        }
+    }
+
     private static bool IsMatch(byte[] haystack, int position, byte[] needle)
     {
         for (var i = 0; i < needle.Length; i++)
@@ -98,6 +233,45 @@ internal sealed class SeekableZipHeaderFactory : ZipHeaderFactory
         return true;
     }
 
+    private static async ValueTask SeekBackToHeaderAsync(Stream stream, AsyncBinaryReader reader)
+    {
+        // Minimum EOCD length
+        if (stream.Length < MINIMUM_EOCD_LENGTH)
+        {
+            throw new ArchiveException(
+                "Could not find Zip file Directory at the end of the file. File may be corrupted."
+            );
+        }
+
+        var len =
+            stream.Length < MAX_SEARCH_LENGTH_FOR_EOCD
+                ? (int)stream.Length
+                : MAX_SEARCH_LENGTH_FOR_EOCD;
+        // We search for marker in reverse to find the first occurance
+        byte[] needle = { 0x06, 0x05, 0x4b, 0x50 };
+
+        stream.Seek(-len, SeekOrigin.End);
+
+        var seek = await reader.ReadBytesAsync(len);
+
+        // Search in reverse
+        Array.Reverse(seek);
+
+        // don't exclude the minimum eocd region, otherwise you fail to locate the header in empty zip files
+        var max_search_area = len; // - MINIMUM_EOCD_LENGTH;
+
+        for (var pos_from_end = 0; pos_from_end < max_search_area; ++pos_from_end)
+        {
+            if (IsMatch(seek, pos_from_end, needle))
+            {
+                stream.Seek(-pos_from_end, SeekOrigin.End);
+                return;
+            }
+        }
+
+        throw new ArchiveException("Failed to locate the Zip Header");
+    }
+
     private static void SeekBackToHeader(Stream stream, BinaryReader reader)
     {
         // Minimum EOCD length
@@ -163,4 +337,31 @@ internal sealed class SeekableZipHeaderFactory : ZipHeaderFactory
         }
         return localEntryHeader;
     }
+
+    internal async ValueTask<LocalEntryHeader> GetLocalHeaderAsync(
+        Stream stream,
+        DirectoryEntryHeader directoryEntryHeader
+    )
+    {
+        stream.Seek(directoryEntryHeader.RelativeOffsetOfEntryHeader, SeekOrigin.Begin);
+        var reader = new AsyncBinaryReader(stream);
+        var signature = await reader.ReadUInt32Async();
+        if (await ReadHeader(signature, reader, _zip64) is not LocalEntryHeader localEntryHeader)
+        {
+            throw new InvalidOperationException();
+        }
+
+        // populate fields only known from the DirectoryEntryHeader
+        localEntryHeader.HasData = directoryEntryHeader.HasData;
+        localEntryHeader.ExternalFileAttributes = directoryEntryHeader.ExternalFileAttributes;
+        localEntryHeader.Comment = directoryEntryHeader.Comment;
+
+        if (FlagUtility.HasFlag(localEntryHeader.Flags, HeaderFlags.UsePostDataDescriptor))
+        {
+            localEntryHeader.Crc = directoryEntryHeader.Crc;
+            localEntryHeader.CompressedSize = directoryEntryHeader.CompressedSize;
+            localEntryHeader.UncompressedSize = directoryEntryHeader.UncompressedSize;
+        }
+        return localEntryHeader;
+    }
 }

src/SharpCompress/Common/Zip/StreamingZipFilePart.cs

@@ -1,4 +1,6 @@
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common.Zip.Headers;
 using SharpCompress.Compressors.Deflate;
 using SharpCompress.IO;
@@ -31,6 +33,28 @@ internal sealed class StreamingZipFilePart : ZipFilePart
         return _decompressionStream;
     }
 
+    internal override async ValueTask<Stream?> GetCompressedStreamAsync(
+        CancellationToken cancellationToken = default
+    )
+    {
+        if (!Header.HasData)
+        {
+            return Stream.Null;
+        }
+        _decompressionStream = await CreateDecompressionStreamAsync(
+                await GetCryptoStreamAsync(CreateBaseStream(), cancellationToken)
+                    .ConfigureAwait(false),
+                Header.CompressionMethod,
+                cancellationToken
+            )
+            .ConfigureAwait(false);
+        if (LeaveStreamOpen)
+        {
+            return SharpCompressStream.Create(_decompressionStream, leaveOpen: true);
+        }
+        return _decompressionStream;
+    }
+
     internal BinaryReader FixStreamedFileLocation(ref SharpCompressStream rewindableStream)
     {
         if (Header.IsDirectory)

src/SharpCompress/Common/Zip/StreamingZipHeaderFactory.cs

@@ -2,6 +2,9 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using SharpCompress.Common;
 using SharpCompress.Common.Zip.Headers;
 using SharpCompress.IO;
 
@@ -13,7 +16,7 @@ internal class StreamingZipHeaderFactory : ZipHeaderFactory
 
     internal StreamingZipHeaderFactory(
         string? password,
-        ArchiveEncoding archiveEncoding,
+        IArchiveEncoding archiveEncoding,
         IEnumerable<ZipEntry>? entries
     )
         : base(StreamingMode.Streaming, password, archiveEncoding) => _entries = entries;
@@ -200,4 +203,331 @@ internal class StreamingZipHeaderFactory : ZipHeaderFactory
             yield return header;
         }
     }
+
+    /// <summary>
+    /// Reads ZIP headers asynchronously for streams that do not support synchronous reads.
+    /// </summary>
+    internal IAsyncEnumerable<ZipHeader> ReadStreamHeaderAsync(Stream stream) =>
+        new StreamHeaderAsyncEnumerable(this, stream);
+
+    /// <summary>
+    /// Invokes the shared async header parsing logic on the base factory.
+    /// </summary>
+    private ValueTask<ZipHeader?> ReadHeaderAsyncInternal(
+        uint headerBytes,
+        AsyncBinaryReader reader
+    ) => ReadHeader(headerBytes, reader);
+
+    /// <summary>
+    /// Exposes the last parsed local entry header to the async enumerator so it can handle streaming data descriptors.
+    /// </summary>
+    private LocalEntryHeader? LastEntryHeader
+    {
+        get => _lastEntryHeader;
+        set => _lastEntryHeader = value;
+    }
+
+    /// <summary>
+    /// Produces an async enumerator for streaming ZIP headers.
+    /// </summary>
+    private sealed class StreamHeaderAsyncEnumerable : IAsyncEnumerable<ZipHeader>
+    {
+        private readonly StreamingZipHeaderFactory _headerFactory;
+        private readonly Stream _stream;
+
+        public StreamHeaderAsyncEnumerable(StreamingZipHeaderFactory headerFactory, Stream stream)
+        {
+            _headerFactory = headerFactory;
+            _stream = stream;
+        }
+
+        public IAsyncEnumerator<ZipHeader> GetAsyncEnumerator(
+            CancellationToken cancellationToken = default
+        ) => new StreamHeaderAsyncEnumerator(_headerFactory, _stream, cancellationToken);
+    }
+
+    /// <summary>
+    /// Async implementation of <see cref="ReadStreamHeader"/> using <see cref="AsyncBinaryReader"/> to avoid sync reads.
+    /// </summary>
+    private sealed class StreamHeaderAsyncEnumerator : IAsyncEnumerator<ZipHeader>, IDisposable
+    {
+        private readonly StreamingZipHeaderFactory _headerFactory;
+        private readonly SharpCompressStream _rewindableStream;
+        private readonly AsyncBinaryReader _reader;
+        private readonly CancellationToken _cancellationToken;
+        private bool _completed;
+
+        public StreamHeaderAsyncEnumerator(
+            StreamingZipHeaderFactory headerFactory,
+            Stream stream,
+            CancellationToken cancellationToken
+        )
+        {
+            _headerFactory = headerFactory;
+            _rewindableStream = EnsureSharpCompressStream(stream);
+            _reader = new AsyncBinaryReader(_rewindableStream, leaveOpen: true);
+            _cancellationToken = cancellationToken;
+        }
+
+        private ZipHeader? _current;
+
+        public ZipHeader Current =>
+            _current ?? throw new InvalidOperationException("No current header is available.");
+
+        /// <summary>
+        /// Advances to the next ZIP header in the stream, honoring streaming data descriptors where applicable.
+        /// </summary>
+        public async ValueTask<bool> MoveNextAsync()
+        {
+            if (_completed)
+            {
+                return false;
+            }
+
+            while (true)
+            {
+                _cancellationToken.ThrowIfCancellationRequested();
+
+                uint headerBytes;
+                var lastEntryHeader = _headerFactory.LastEntryHeader;
+                if (
+                    lastEntryHeader != null
+                    && FlagUtility.HasFlag(lastEntryHeader.Flags, HeaderFlags.UsePostDataDescriptor)
+                )
+                {
+                    if (lastEntryHeader.Part is null)
+                    {
+                        continue;
+                    }
+
+                    var pos = _rewindableStream.CanSeek ? (long?)_rewindableStream.Position : null;
+
+                    var crc = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+                    if (crc == POST_DATA_DESCRIPTOR)
+                    {
+                        crc = await _reader
+                            .ReadUInt32Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                    }
+                    lastEntryHeader.Crc = crc;
+
+                    //attempt 32bit read
+                    ulong compressedSize = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+                    ulong uncompressedSize = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+                    headerBytes = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+
+                    //check for zip64 sentinel or unexpected header
+                    bool isSentinel =
+                        compressedSize == 0xFFFFFFFF || uncompressedSize == 0xFFFFFFFF;
+                    bool isHeader = headerBytes == 0x04034b50 || headerBytes == 0x02014b50;
+
+                    if (!isHeader && !isSentinel)
+                    {
+                        //reshuffle into 64-bit values
+                        compressedSize = (uncompressedSize << 32) | compressedSize;
+                        uncompressedSize =
+                            ((ulong)headerBytes << 32)
+                            | await _reader
+                                .ReadUInt32Async(_cancellationToken)
+                                .ConfigureAwait(false);
+                        headerBytes = await _reader
+                            .ReadUInt32Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                    }
+                    else if (isSentinel)
+                    {
+                        //standards-compliant zip64 descriptor
+                        compressedSize = await _reader
+                            .ReadUInt64Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                        uncompressedSize = await _reader
+                            .ReadUInt64Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                    }
+
+                    lastEntryHeader.CompressedSize = (long)compressedSize;
+                    lastEntryHeader.UncompressedSize = (long)uncompressedSize;
+
+                    if (pos.HasValue)
+                    {
+                        lastEntryHeader.DataStartPosition = pos - lastEntryHeader.CompressedSize;
+                    }
+                }
+                else if (lastEntryHeader != null && lastEntryHeader.IsZip64)
+                {
+                    if (lastEntryHeader.Part is null)
+                    {
+                        continue;
+                    }
+
+                    var pos = _rewindableStream.CanSeek ? (long?)_rewindableStream.Position : null;
+
+                    headerBytes = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+
+                    _ = await _reader.ReadUInt16Async(_cancellationToken).ConfigureAwait(false); // version
+                    _ = await _reader.ReadUInt16Async(_cancellationToken).ConfigureAwait(false); // flags
+                    _ = await _reader.ReadUInt16Async(_cancellationToken).ConfigureAwait(false); // compressionMethod
+                    _ = await _reader.ReadUInt16Async(_cancellationToken).ConfigureAwait(false); // lastModifiedDate
+                    _ = await _reader.ReadUInt16Async(_cancellationToken).ConfigureAwait(false); // lastModifiedTime
+
+                    var crc = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+
+                    if (crc == POST_DATA_DESCRIPTOR)
+                    {
+                        crc = await _reader
+                            .ReadUInt32Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                    }
+                    lastEntryHeader.Crc = crc;
+
+                    // The DataDescriptor can be either 64bit or 32bit
+                    var compressedSize = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+                    var uncompressedSize = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+
+                    // Check if we have header or 64bit DataDescriptor
+                    var testHeader = !(headerBytes == 0x04034b50 || headerBytes == 0x02014b50);
+
+                    var test64Bit = ((long)uncompressedSize << 32) | compressedSize;
+                    if (test64Bit == lastEntryHeader.CompressedSize && testHeader)
+                    {
+                        lastEntryHeader.UncompressedSize =
+                            (
+                                (long)
+                                    await _reader
+                                        .ReadUInt32Async(_cancellationToken)
+                                        .ConfigureAwait(false) << 32
+                            ) | headerBytes;
+                        headerBytes = await _reader
+                            .ReadUInt32Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                    }
+                    else
+                    {
+                        lastEntryHeader.UncompressedSize = uncompressedSize;
+                    }
+
+                    if (pos.HasValue)
+                    {
+                        lastEntryHeader.DataStartPosition = pos - lastEntryHeader.CompressedSize;
+
+                        // 4 = First 4 bytes of the entry header (i.e. 50 4B 03 04)
+                        _rewindableStream.Position = pos.Value + 4;
+                    }
+                }
+                else
+                {
+                    headerBytes = await _reader
+                        .ReadUInt32Async(_cancellationToken)
+                        .ConfigureAwait(false);
+                }
+
+                _headerFactory.LastEntryHeader = null;
+                var header = await _headerFactory
+                    .ReadHeaderAsyncInternal(headerBytes, _reader)
+                    .ConfigureAwait(false);
+                if (header is null)
+                {
+                    _completed = true;
+                    return false;
+                }
+
+                //entry could be zero bytes so we need to know that.
+                if (header.ZipHeaderType == ZipHeaderType.LocalEntry)
+                {
+                    var localHeader = (LocalEntryHeader)header;
+                    var directoryHeader = _headerFactory._entries?.FirstOrDefault(entry =>
+                        entry.Key == localHeader.Name
+                        && localHeader.CompressedSize == 0
+                        && localHeader.UncompressedSize == 0
+                        && localHeader.Crc == 0
+                        && localHeader.IsDirectory == false
+                    );
+
+                    if (directoryHeader != null)
+                    {
+                        localHeader.UncompressedSize = directoryHeader.Size;
+                        localHeader.CompressedSize = directoryHeader.CompressedSize;
+                        localHeader.Crc = (uint)directoryHeader.Crc;
+                    }
+
+                    // If we have CompressedSize, there is data to be read
+                    if (localHeader.CompressedSize > 0)
+                    {
+                        header.HasData = true;
+                    } // Check if zip is streaming ( Length is 0 and is declared in PostDataDescriptor )
+                    else if (localHeader.Flags.HasFlag(HeaderFlags.UsePostDataDescriptor))
+                    {
+                        var nextHeaderBytes = await _reader
+                            .ReadUInt32Async(_cancellationToken)
+                            .ConfigureAwait(false);
+                        ((IStreamStack)_rewindableStream).Rewind(sizeof(uint));
+
+                        // Check if next data is PostDataDescriptor, streamed file with 0 length
+                        header.HasData = !IsHeader(nextHeaderBytes);
+                    }
+                    else // We are not streaming and compressed size is 0, we have no data
+                    {
+                        header.HasData = false;
+                    }
+                }
+
+                _current = header;
+                return true;
+            }
+        }
+
+        public ValueTask DisposeAsync()
+        {
+            Dispose();
+            return default;
+        }
+
+        /// <summary>
+        /// Disposes the underlying reader (without closing the archive stream).
+        /// </summary>
+        public void Dispose()
+        {
+            _reader.Dispose();
+        }
+
+        /// <summary>
+        /// Ensures the stream is a <see cref="SharpCompressStream"/> so header parsing can use rewind/buffer helpers.
+        /// </summary>
+        private static SharpCompressStream EnsureSharpCompressStream(Stream stream)
+        {
+            if (stream is SharpCompressStream sharpCompressStream)
+            {
+                return sharpCompressStream;
+            }
+
+            // Ensure the stream is already a SharpCompressStream so the buffer/size is set.
+            // The original code wrapped this with RewindableStream; use SharpCompressStream so we can get the buffer size.
+            if (stream is SourceStream src)
+            {
+                return new SharpCompressStream(
+                    stream,
+                    src.ReaderOptions.LeaveStreamOpen,
+                    bufferSize: src.ReaderOptions.BufferSize
+                );
+            }
+
+            throw new ArgumentException("Stream must be a SharpCompressStream", nameof(stream));
+        }
+    }
 }

src/SharpCompress/Common/Zip/WinzipAesEncryptionData.cs

@@ -20,7 +20,7 @@ internal class WinzipAesEncryptionData
     {
         _keySize = keySize;
 
-#if NETFRAMEWORK
+#if NETFRAMEWORK || NETSTANDARD2_0
         var rfc2898 = new Rfc2898DeriveBytes(password, salt, RFC2898_ITERATIONS);
         KeyBytes = rfc2898.GetBytes(KeySizeInBytes);
         IvBytes = rfc2898.GetBytes(KeySizeInBytes);

src/SharpCompress/Common/Zip/ZipEntry.cs

@@ -2,7 +2,6 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using SharpCompress.Common.Zip.Headers;
-using SharpCompress.Common.Zip.SOZip;
 
 namespace SharpCompress.Common.Zip;
 
@@ -12,7 +11,7 @@ public class ZipEntry : Entry
 
     internal ZipEntry(ZipFilePart? filePart)
     {
-        if (filePart is null)
+        if (filePart == null)
         {
             return;
         }
@@ -89,24 +88,4 @@ public class ZipEntry : Entry
     public override int? Attrib => (int?)_filePart?.Header.ExternalFileAttributes;
 
     public string? Comment => _filePart?.Header.Comment;
-
-    /// <summary>
-    /// Gets a value indicating whether this entry has SOZip (Seek-Optimized ZIP) support.
-    /// A SOZip entry has an associated index file that enables random access within
-    /// the compressed data.
-    /// </summary>
-    public bool IsSozip => _filePart?.Header.Extra.Any(e => e.Type == ExtraDataType.SOZip) ?? false;
-
-    /// <summary>
-    /// Gets a value indicating whether this entry is a SOZip index file.
-    /// Index files are hidden files with a .sozip.idx extension that contain
-    /// offsets into the main compressed file.
-    /// </summary>
-    public bool IsSozipIndexFile => Key is not null && SOZipIndex.IsIndexFile(Key);
-
-    /// <summary>
-    /// Gets the SOZip extra field data, if present.
-    /// </summary>
-    internal SOZipExtraField? SOZipExtra =>
-        _filePart?.Header.Extra.OfType<SOZipExtraField>().FirstOrDefault();
 }

src/SharpCompress/Common/Zip/ZipFilePart.cs

@@ -2,6 +2,8 @@ using System;
 using System.Buffers.Binary;
 using System.IO;
 using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common.Zip.Headers;
 using SharpCompress.Compressors;
 using SharpCompress.Compressors.BZip2;
@@ -264,4 +266,244 @@ internal abstract class ZipFilePart : FilePart
         }
         return plainStream;
     }
+
+    internal override async ValueTask<Stream?> GetCompressedStreamAsync(
+        CancellationToken cancellationToken = default
+    )
+    {
+        if (!Header.HasData)
+        {
+            return Stream.Null;
+        }
+        var decompressionStream = await CreateDecompressionStreamAsync(
+                await GetCryptoStreamAsync(CreateBaseStream(), cancellationToken)
+                    .ConfigureAwait(false),
+                Header.CompressionMethod,
+                cancellationToken
+            )
+            .ConfigureAwait(false);
+        if (LeaveStreamOpen)
+        {
+            return SharpCompressStream.Create(decompressionStream, leaveOpen: true);
+        }
+        return decompressionStream;
+    }
+
+    protected async Task<Stream> GetCryptoStreamAsync(
+        Stream plainStream,
+        CancellationToken cancellationToken = default
+    )
+    {
+        var isFileEncrypted = FlagUtility.HasFlag(Header.Flags, HeaderFlags.Encrypted);
+
+        if (Header.CompressedSize == 0 && isFileEncrypted)
+        {
+            throw new NotSupportedException("Cannot encrypt file with unknown size at start.");
+        }
+
+        if (
+            (
+                Header.CompressedSize == 0
+                && FlagUtility.HasFlag(Header.Flags, HeaderFlags.UsePostDataDescriptor)
+            ) || Header.IsZip64
+        )
+        {
+            plainStream = SharpCompressStream.Create(plainStream, leaveOpen: true); //make sure AES doesn't close
+        }
+        else
+        {
+            plainStream = new ReadOnlySubStream(plainStream, Header.CompressedSize); //make sure AES doesn't close
+        }
+
+        if (isFileEncrypted)
+        {
+            switch (Header.CompressionMethod)
+            {
+                case ZipCompressionMethod.None:
+                case ZipCompressionMethod.Shrink:
+                case ZipCompressionMethod.Reduce1:
+                case ZipCompressionMethod.Reduce2:
+                case ZipCompressionMethod.Reduce3:
+                case ZipCompressionMethod.Reduce4:
+                case ZipCompressionMethod.Deflate:
+                case ZipCompressionMethod.Deflate64:
+                case ZipCompressionMethod.BZip2:
+                case ZipCompressionMethod.LZMA:
+                case ZipCompressionMethod.PPMd:
+                {
+                    return new PkwareTraditionalCryptoStream(
+                        plainStream,
+                        await Header
+                            .ComposeEncryptionDataAsync(plainStream, cancellationToken)
+                            .ConfigureAwait(false),
+                        CryptoMode.Decrypt
+                    );
+                }
+
+                case ZipCompressionMethod.WinzipAes:
+                {
+                    if (Header.WinzipAesEncryptionData != null)
+                    {
+                        return new WinzipAesCryptoStream(
+                            plainStream,
+                            Header.WinzipAesEncryptionData,
+                            Header.CompressedSize - 10
+                        );
+                    }
+                    return plainStream;
+                }
+
+                default:
+                {
+                    throw new InvalidOperationException("Header.CompressionMethod is invalid");
+                }
+            }
+        }
+        return plainStream;
+    }
+
+    protected async Task<Stream> CreateDecompressionStreamAsync(
+        Stream stream,
+        ZipCompressionMethod method,
+        CancellationToken cancellationToken = default
+    )
+    {
+        switch (method)
+        {
+            case ZipCompressionMethod.None:
+            {
+                if (Header.CompressedSize is 0)
+                {
+                    return new DataDescriptorStream(stream);
+                }
+
+                return stream;
+            }
+            case ZipCompressionMethod.Shrink:
+            {
+                return new ShrinkStream(
+                    stream,
+                    CompressionMode.Decompress,
+                    Header.CompressedSize,
+                    Header.UncompressedSize
+                );
+            }
+            case ZipCompressionMethod.Reduce1:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 1);
+            }
+            case ZipCompressionMethod.Reduce2:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 2);
+            }
+            case ZipCompressionMethod.Reduce3:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 3);
+            }
+            case ZipCompressionMethod.Reduce4:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 4);
+            }
+            case ZipCompressionMethod.Explode:
+            {
+                return new ExplodeStream(
+                    stream,
+                    Header.CompressedSize,
+                    Header.UncompressedSize,
+                    Header.Flags
+                );
+            }
+
+            case ZipCompressionMethod.Deflate:
+            {
+                return new DeflateStream(stream, CompressionMode.Decompress);
+            }
+            case ZipCompressionMethod.Deflate64:
+            {
+                return new Deflate64Stream(stream, CompressionMode.Decompress);
+            }
+            case ZipCompressionMethod.BZip2:
+            {
+                return new BZip2Stream(stream, CompressionMode.Decompress, false);
+            }
+            case ZipCompressionMethod.LZMA:
+            {
+                if (FlagUtility.HasFlag(Header.Flags, HeaderFlags.Encrypted))
+                {
+                    throw new NotSupportedException("LZMA with pkware encryption.");
+                }
+                var buffer = new byte[4];
+                await stream.ReadFullyAsync(buffer, 0, 4, cancellationToken).ConfigureAwait(false);
+                var version = BinaryPrimitives.ReadUInt16LittleEndian(buffer.AsSpan(0, 2));
+                var propsSize = BinaryPrimitives.ReadUInt16LittleEndian(buffer.AsSpan(2, 2));
+                var props = new byte[propsSize];
+                await stream
+                    .ReadFullyAsync(props, 0, propsSize, cancellationToken)
+                    .ConfigureAwait(false);
+                return new LzmaStream(
+                    props,
+                    stream,
+                    Header.CompressedSize > 0 ? Header.CompressedSize - 4 - props.Length : -1,
+                    FlagUtility.HasFlag(Header.Flags, HeaderFlags.Bit1)
+                        ? -1
+                        : Header.UncompressedSize
+                );
+            }
+            case ZipCompressionMethod.Xz:
+            {
+                return new XZStream(stream);
+            }
+            case ZipCompressionMethod.ZStandard:
+            {
+                return new DecompressionStream(stream);
+            }
+            case ZipCompressionMethod.PPMd:
+            {
+                var props = new byte[2];
+                await stream.ReadFullyAsync(props, 0, 2, cancellationToken).ConfigureAwait(false);
+                return new PpmdStream(new PpmdProperties(props), stream, false);
+            }
+            case ZipCompressionMethod.WinzipAes:
+            {
+                var data = Header.Extra.SingleOrDefault(x => x.Type == ExtraDataType.WinZipAes);
+                if (data is null)
+                {
+                    throw new InvalidFormatException("No Winzip AES extra data found.");
+                }
+
+                if (data.Length != 7)
+                {
+                    throw new InvalidFormatException("Winzip data length is not 7.");
+                }
+
+                var compressedMethod = BinaryPrimitives.ReadUInt16LittleEndian(data.DataBytes);
+
+                if (compressedMethod != 0x01 && compressedMethod != 0x02)
+                {
+                    throw new InvalidFormatException(
+                        "Unexpected vendor version number for WinZip AES metadata"
+                    );
+                }
+
+                var vendorId = BinaryPrimitives.ReadUInt16LittleEndian(data.DataBytes.AsSpan(2));
+                if (vendorId != 0x4541)
+                {
+                    throw new InvalidFormatException(
+                        "Unexpected vendor ID for WinZip AES metadata"
+                    );
+                }
+
+                return await CreateDecompressionStreamAsync(
+                    stream,
+                    (ZipCompressionMethod)
+                        BinaryPrimitives.ReadUInt16LittleEndian(data.DataBytes.AsSpan(5)),
+                    cancellationToken
+                );
+            }
+            default:
+            {
+                throw new NotSupportedException("CompressionMethod: " + Header.CompressionMethod);
+            }
+        }
+    }
 }

src/SharpCompress/Common/Zip/ZipHeaderFactory.cs

@@ -1,6 +1,8 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
+using SharpCompress;
 using SharpCompress.Common.Zip.Headers;
 using SharpCompress.IO;
 
@@ -21,12 +23,12 @@ internal class ZipHeaderFactory
     protected LocalEntryHeader? _lastEntryHeader;
     private readonly string? _password;
     private readonly StreamingMode _mode;
-    private readonly ArchiveEncoding _archiveEncoding;
+    private readonly IArchiveEncoding _archiveEncoding;
 
     protected ZipHeaderFactory(
         StreamingMode mode,
         string? password,
-        ArchiveEncoding archiveEncoding
+        IArchiveEncoding archiveEncoding
     )
     {
         _mode = mode;
@@ -34,6 +36,82 @@ internal class ZipHeaderFactory
         _archiveEncoding = archiveEncoding;
     }
 
+    protected async ValueTask<ZipHeader?> ReadHeader(
+        uint headerBytes,
+        AsyncBinaryReader reader,
+        bool zip64 = false
+    )
+    {
+        switch (headerBytes)
+        {
+            case ENTRY_HEADER_BYTES:
+            {
+                var entryHeader = new LocalEntryHeader(_archiveEncoding);
+                await entryHeader.Read(reader);
+                await LoadHeaderAsync(entryHeader, reader.BaseStream).ConfigureAwait(false);
+
+                _lastEntryHeader = entryHeader;
+                return entryHeader;
+            }
+            case DIRECTORY_START_HEADER_BYTES:
+            {
+                var entry = new DirectoryEntryHeader(_archiveEncoding);
+                await entry.Read(reader);
+                return entry;
+            }
+            case POST_DATA_DESCRIPTOR:
+            {
+                if (
+                    _lastEntryHeader != null
+                    && FlagUtility.HasFlag(
+                        _lastEntryHeader.NotNull().Flags,
+                        HeaderFlags.UsePostDataDescriptor
+                    )
+                )
+                {
+                    _lastEntryHeader.Crc = await reader.ReadUInt32Async();
+                    _lastEntryHeader.CompressedSize = zip64
+                        ? (long)await reader.ReadUInt64Async()
+                        : await reader.ReadUInt32Async();
+                    _lastEntryHeader.UncompressedSize = zip64
+                        ? (long)await reader.ReadUInt64Async()
+                        : await reader.ReadUInt32Async();
+                }
+                else
+                {
+                    await reader.ReadBytesAsync(zip64 ? 20 : 12);
+                }
+                return null;
+            }
+            case DIGITAL_SIGNATURE:
+                return null;
+            case DIRECTORY_END_HEADER_BYTES:
+            {
+                var entry = new DirectoryEndHeader();
+                await entry.Read(reader);
+                return entry;
+            }
+            case SPLIT_ARCHIVE_HEADER_BYTES:
+            {
+                return new SplitHeader();
+            }
+            case ZIP64_END_OF_CENTRAL_DIRECTORY:
+            {
+                var entry = new Zip64DirectoryEndHeader();
+                await entry.Read(reader);
+                return entry;
+            }
+            case ZIP64_END_OF_CENTRAL_DIRECTORY_LOCATOR:
+            {
+                var entry = new Zip64DirectoryEndLocatorHeader();
+                await entry.Read(reader);
+                return entry;
+            }
+            default:
+                return null;
+        }
+    }
+
     protected ZipHeader? ReadHeader(uint headerBytes, BinaryReader reader, bool zip64 = false)
     {
         switch (headerBytes)
@@ -205,4 +283,82 @@ internal class ZipHeaderFactory
 
         //}
     }
+
+    /// <summary>
+    /// Loads encryption metadata and stream positioning for a header using async reads where needed.
+    /// </summary>
+    private async ValueTask LoadHeaderAsync(ZipFileEntry entryHeader, Stream stream)
+    {
+        if (FlagUtility.HasFlag(entryHeader.Flags, HeaderFlags.Encrypted))
+        {
+            if (
+                !entryHeader.IsDirectory
+                && entryHeader.CompressedSize == 0
+                && FlagUtility.HasFlag(entryHeader.Flags, HeaderFlags.UsePostDataDescriptor)
+            )
+            {
+                throw new NotSupportedException(
+                    "SharpCompress cannot currently read non-seekable Zip Streams with encrypted data that has been written in a non-seekable manner."
+                );
+            }
+
+            if (_password is null)
+            {
+                throw new CryptographicException("No password supplied for encrypted zip.");
+            }
+
+            entryHeader.Password = _password;
+
+            if (entryHeader.CompressionMethod == ZipCompressionMethod.WinzipAes)
+            {
+                var data = entryHeader.Extra.SingleOrDefault(x =>
+                    x.Type == ExtraDataType.WinZipAes
+                );
+                if (data != null)
+                {
+                    var keySize = (WinzipAesKeySize)data.DataBytes[4];
+
+                    var salt = new byte[WinzipAesEncryptionData.KeyLengthInBytes(keySize) / 2];
+                    var passwordVerifyValue = new byte[2];
+                    await stream.ReadExactAsync(salt, 0, salt.Length).ConfigureAwait(false);
+                    await stream.ReadExactAsync(passwordVerifyValue, 0, 2).ConfigureAwait(false);
+
+                    entryHeader.WinzipAesEncryptionData = new WinzipAesEncryptionData(
+                        keySize,
+                        salt,
+                        passwordVerifyValue,
+                        _password
+                    );
+
+                    entryHeader.CompressedSize -= (uint)(salt.Length + 2);
+                }
+            }
+        }
+
+        if (entryHeader.IsDirectory)
+        {
+            return;
+        }
+
+        switch (_mode)
+        {
+            case StreamingMode.Seekable:
+            {
+                entryHeader.DataStartPosition = stream.Position;
+                stream.Position += entryHeader.CompressedSize;
+                break;
+            }
+
+            case StreamingMode.Streaming:
+            {
+                entryHeader.PackedStream = stream;
+                break;
+            }
+
+            default:
+            {
+                throw new InvalidFormatException("Invalid StreamingMode");
+            }
+        }
+    }
 }

src/SharpCompress/Compressors/ADC/ADCBase.cs

@@ -104,7 +104,7 @@ public static class ADCBase
     /// <param name="bufferSize">Max size for decompressed data</param>
     /// <param name="cancellationToken">Cancellation token</param>
     /// <returns>Result containing bytes read and decompressed data</returns>
-    public static async Task<AdcDecompressResult> DecompressAsync(
+    public static async ValueTask<AdcDecompressResult> DecompressAsync(
         byte[] input,
         int bufferSize = 262144,
         CancellationToken cancellationToken = default
@@ -117,7 +117,7 @@ public static class ADCBase
     /// <param name="bufferSize">Max size for decompressed data</param>
     /// <param name="cancellationToken">Cancellation token</param>
     /// <returns>Result containing bytes read and decompressed data</returns>
-    public static async Task<AdcDecompressResult> DecompressAsync(
+    public static async ValueTask<AdcDecompressResult> DecompressAsync(
         Stream input,
         int bufferSize = 262144,
         CancellationToken cancellationToken = default

src/SharpCompress/Compressors/Deflate/ZlibBaseStream.cs

@@ -400,7 +400,7 @@ internal class ZlibBaseStream : Stream, IStreamStack
         }
     }
 
-    private async Task finishAsync(CancellationToken cancellationToken = default)
+    private async ValueTask finishAsync(CancellationToken cancellationToken = default)
     {
         if (_z is null)
         {
@@ -646,7 +646,9 @@ internal class ZlibBaseStream : Stream, IStreamStack
         return _encoding.GetString(buffer, 0, buffer.Length);
     }
 
-    private async Task<string> ReadZeroTerminatedStringAsync(CancellationToken cancellationToken)
+    private async ValueTask<string> ReadZeroTerminatedStringAsync(
+        CancellationToken cancellationToken
+    )
     {
         var list = new List<byte>();
         var done = false;
@@ -729,7 +731,9 @@ internal class ZlibBaseStream : Stream, IStreamStack
         return totalBytesRead;
     }
 
-    private async Task<int> _ReadAndValidateGzipHeaderAsync(CancellationToken cancellationToken)
+    private async ValueTask<int> _ReadAndValidateGzipHeaderAsync(
+        CancellationToken cancellationToken
+    )
     {
         var totalBytesRead = 0;
 

src/SharpCompress/Compressors/LZMA/LZ/LzOutWindow.cs

@@ -87,7 +87,7 @@ internal class OutWindow : IDisposable
         _stream = null;
     }
 
-    public async Task ReleaseStreamAsync(CancellationToken cancellationToken = default)
+    public async ValueTask ReleaseStreamAsync(CancellationToken cancellationToken = default)
     {
         await FlushAsync(cancellationToken).ConfigureAwait(false);
         _stream = null;
@@ -112,7 +112,7 @@ internal class OutWindow : IDisposable
         _streamPos = _pos;
     }
 
-    private async Task FlushAsync(CancellationToken cancellationToken = default)
+    private async ValueTask FlushAsync(CancellationToken cancellationToken = default)
     {
         if (_stream is null)
         {
@@ -153,7 +153,7 @@ internal class OutWindow : IDisposable
         _pendingLen = rem;
     }
 
-    public async Task CopyPendingAsync(CancellationToken cancellationToken = default)
+    public async ValueTask CopyPendingAsync(CancellationToken cancellationToken = default)
     {
         if (_pendingLen < 1)
         {
@@ -206,7 +206,7 @@ internal class OutWindow : IDisposable
         _pendingDist = distance;
     }
 
-    public async Task CopyBlockAsync(
+    public async ValueTask CopyBlockAsync(
         int distance,
         int len,
         CancellationToken cancellationToken = default
@@ -253,7 +253,7 @@ internal class OutWindow : IDisposable
         }
     }
 
-    public async Task PutByteAsync(byte b, CancellationToken cancellationToken = default)
+    public async ValueTask PutByteAsync(byte b, CancellationToken cancellationToken = default)
     {
         _buffer[_pos++] = b;
         _total++;
@@ -303,7 +303,7 @@ internal class OutWindow : IDisposable
         return len - size;
     }
 
-    public async Task<int> CopyStreamAsync(
+    public async ValueTask<int> CopyStreamAsync(
         Stream stream,
         int len,
         CancellationToken cancellationToken = default
@@ -369,6 +369,28 @@ internal class OutWindow : IDisposable
         return size;
     }
 
+    public int Read(Memory<byte> buffer, int offset, int count)
+    {
+        if (_streamPos >= _pos)
+        {
+            return 0;
+        }
+
+        var size = _pos - _streamPos;
+        if (size > count)
+        {
+            size = count;
+        }
+        _buffer.AsMemory(_streamPos, size).CopyTo(buffer.Slice(offset, size));
+        _streamPos += size;
+        if (_streamPos >= _windowSize)
+        {
+            _pos = 0;
+            _streamPos = 0;
+        }
+        return size;
+    }
+
     public int ReadByte()
     {
         if (_streamPos >= _pos)

src/SharpCompress/Compressors/LZMA/LZipStream.cs

@@ -45,10 +45,12 @@ public sealed class LZipStream : Stream, IStreamStack
     private bool _finished;
 
     private long _writeCount;
+    private readonly Stream? _originalStream;
 
     public LZipStream(Stream stream, CompressionMode mode)
     {
         Mode = mode;
+        _originalStream = stream;
 
         if (mode == CompressionMode.Decompress)
         {
@@ -125,6 +127,10 @@ public sealed class LZipStream : Stream, IStreamStack
         {
             Finish();
             _stream.Dispose();
+            if (Mode == CompressionMode.Compress)
+            {
+                _originalStream?.Dispose();
+            }
         }
     }
 

src/SharpCompress/Compressors/LZMA/LzmaDecoder.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
+using System.Threading.Tasks;
 using SharpCompress.Compressors.LZMA.LZ;
 using SharpCompress.Compressors.LZMA.RangeCoder;
 
@@ -475,7 +476,7 @@ public class Decoder : ICoder, ISetDecoderProperties // ,System.IO.Stream
         return false;
     }
 
-    internal async System.Threading.Tasks.Task<bool> CodeAsync(
+    internal async ValueTask<bool> CodeAsync(
         int dictionarySize,
         OutWindow outWindow,
         RangeCoder.Decoder rangeDecoder,

src/SharpCompress/Compressors/LZMA/LzmaStream.cs

@@ -425,11 +425,11 @@ public class LzmaStream : Stream, IStreamStack
         }
     }
 
-    private async Task DecodeChunkHeaderAsync(CancellationToken cancellationToken = default)
+    private async ValueTask DecodeChunkHeaderAsync(CancellationToken cancellationToken = default)
     {
         var controlBuffer = new byte[1];
         await _inputStream
-            .ReadExactlyAsync(controlBuffer, 0, 1, cancellationToken)
+            .ReadExactAsync(controlBuffer, 0, 1, cancellationToken)
             .ConfigureAwait(false);
         var control = controlBuffer[0];
         _inputPosition++;
@@ -458,13 +458,13 @@ public class LzmaStream : Stream, IStreamStack
             _availableBytes = (control & 0x1F) << 16;
             var buffer = new byte[2];
             await _inputStream
-                .ReadExactlyAsync(buffer, 0, 2, cancellationToken)
+                .ReadExactAsync(buffer, 0, 2, cancellationToken)
                 .ConfigureAwait(false);
             _availableBytes += (buffer[0] << 8) + buffer[1] + 1;
             _inputPosition += 2;
 
             await _inputStream
-                .ReadExactlyAsync(buffer, 0, 2, cancellationToken)
+                .ReadExactAsync(buffer, 0, 2, cancellationToken)
                 .ConfigureAwait(false);
             _rangeDecoderLimit = (buffer[0] << 8) + buffer[1] + 1;
             _inputPosition += 2;
@@ -473,7 +473,7 @@ public class LzmaStream : Stream, IStreamStack
             {
                 _needProps = false;
                 await _inputStream
-                    .ReadExactlyAsync(controlBuffer, 0, 1, cancellationToken)
+                    .ReadExactAsync(controlBuffer, 0, 1, cancellationToken)
                     .ConfigureAwait(false);
                 Properties[0] = controlBuffer[0];
                 _inputPosition++;
@@ -502,7 +502,7 @@ public class LzmaStream : Stream, IStreamStack
             _uncompressedChunk = true;
             var buffer = new byte[2];
             await _inputStream
-                .ReadExactlyAsync(buffer, 0, 2, cancellationToken)
+                .ReadExactAsync(buffer, 0, 2, cancellationToken)
                 .ConfigureAwait(false);
             _availableBytes = (buffer[0] << 8) + buffer[1] + 1;
             _inputPosition += 2;
@@ -632,6 +632,119 @@ public class LzmaStream : Stream, IStreamStack
         return total;
     }
 
+#if !NETFRAMEWORK && !NETSTANDARD2_0
+    public override async ValueTask<int> ReadAsync(
+        Memory<byte> buffer,
+        CancellationToken cancellationToken = default
+    )
+    {
+        if (_endReached)
+        {
+            return 0;
+        }
+
+        var total = 0;
+        var offset = 0;
+        var count = buffer.Length;
+        while (total < count)
+        {
+            cancellationToken.ThrowIfCancellationRequested();
+
+            if (_availableBytes == 0)
+            {
+                if (_isLzma2)
+                {
+                    await DecodeChunkHeaderAsync(cancellationToken).ConfigureAwait(false);
+                }
+                else
+                {
+                    _endReached = true;
+                }
+                if (_endReached)
+                {
+                    break;
+                }
+            }
+
+            var toProcess = count - total;
+            if (toProcess > _availableBytes)
+            {
+                toProcess = (int)_availableBytes;
+            }
+
+            _outWindow.SetLimit(toProcess);
+            if (_uncompressedChunk)
+            {
+                _inputPosition += await _outWindow
+                    .CopyStreamAsync(_inputStream, toProcess, cancellationToken)
+                    .ConfigureAwait(false);
+            }
+            else if (
+                await _decoder
+                    .CodeAsync(_dictionarySize, _outWindow, _rangeDecoder, cancellationToken)
+                    .ConfigureAwait(false)
+                && _outputSize < 0
+            )
+            {
+                _availableBytes = _outWindow.AvailableBytes;
+            }
+
+            var read = _outWindow.Read(buffer, offset, toProcess);
+            total += read;
+            offset += read;
+            _position += read;
+            _availableBytes -= read;
+
+            if (_availableBytes == 0 && !_uncompressedChunk)
+            {
+                if (
+                    !_rangeDecoder.IsFinished
+                    || (_rangeDecoderLimit >= 0 && _rangeDecoder._total != _rangeDecoderLimit)
+                )
+                {
+                    _outWindow.SetLimit(toProcess + 1);
+                    if (
+                        !await _decoder
+                            .CodeAsync(
+                                _dictionarySize,
+                                _outWindow,
+                                _rangeDecoder,
+                                cancellationToken
+                            )
+                            .ConfigureAwait(false)
+                    )
+                    {
+                        _rangeDecoder.ReleaseStream();
+                        throw new DataErrorException();
+                    }
+                }
+
+                _rangeDecoder.ReleaseStream();
+
+                _inputPosition += _rangeDecoder._total;
+                if (_outWindow.HasPending)
+                {
+                    throw new DataErrorException();
+                }
+            }
+        }
+
+        if (_endReached)
+        {
+            if (_inputSize >= 0 && _inputPosition != _inputSize)
+            {
+                throw new DataErrorException();
+            }
+            if (_outputSize >= 0 && _position != _outputSize)
+            {
+                throw new DataErrorException();
+            }
+        }
+
+        return total;
+    }
+#endif
+
     public override Task WriteAsync(
         byte[] buffer,
         int offset,

src/SharpCompress/Compressors/LZMA/Utilites/Utils.cs

@@ -53,39 +53,4 @@ internal static class Utils
             throw new InvalidOperationException("Assertion failed.");
         }
     }
-
-    public static void ReadExact(this Stream stream, byte[] buffer, int offset, int length)
-    {
-        if (stream is null)
-        {
-            throw new ArgumentNullException(nameof(stream));
-        }
-
-        if (buffer is null)
-        {
-            throw new ArgumentNullException(nameof(buffer));
-        }
-
-        if (offset < 0 || offset > buffer.Length)
-        {
-            throw new ArgumentOutOfRangeException(nameof(offset));
-        }
-
-        if (length < 0 || length > buffer.Length - offset)
-        {
-            throw new ArgumentOutOfRangeException(nameof(length));
-        }
-
-        while (length > 0)
-        {
-            var fetched = stream.Read(buffer, offset, length);
-            if (fetched <= 0)
-            {
-                throw new EndOfStreamException();
-            }
-
-            offset += fetched;
-            length -= fetched;
-        }
-    }
 }

src/SharpCompress/Compressors/Rar/RarStream.cs

@@ -68,7 +68,7 @@ internal class RarStream : Stream, IStreamStack
         _position = 0;
     }
 
-    public async Task InitializeAsync(CancellationToken cancellationToken = default)
+    public async ValueTask InitializeAsync(CancellationToken cancellationToken = default)
     {
         fetch = true;
         await unpack.DoUnpackAsync(fileHeader, readStream, this, cancellationToken);

src/SharpCompress/Compressors/Xz/MultiByteIntegers.cs

@@ -58,7 +58,7 @@ internal static class MultiByteIntegers
             MaxBytes = 9;
         }
 
-        var LastByte = await ReadByteAsync(reader, cancellationToken).ConfigureAwait(false);
+        var LastByte = await reader.ReadByteAsync(cancellationToken).ConfigureAwait(false);
         var Output = (ulong)LastByte & 0x7F;
 
         var i = 0;
@@ -69,7 +69,7 @@ internal static class MultiByteIntegers
                 throw new InvalidFormatException();
             }
 
-            LastByte = await ReadByteAsync(reader, cancellationToken).ConfigureAwait(false);
+            LastByte = await reader.ReadByteAsync(cancellationToken).ConfigureAwait(false);
             if (LastByte == 0)
             {
                 throw new InvalidFormatException();
@@ -79,37 +79,4 @@ internal static class MultiByteIntegers
         }
         return Output;
     }
-
-    public static async Task<byte> ReadByteAsync(
-        this BinaryReader reader,
-        CancellationToken cancellationToken = default
-    )
-    {
-        var buffer = new byte[1];
-        var bytesRead = await reader
-            .BaseStream.ReadAsync(buffer, 0, 1, cancellationToken)
-            .ConfigureAwait(false);
-        if (bytesRead != 1)
-        {
-            throw new EndOfStreamException();
-        }
-        return buffer[0];
-    }
-
-    public static async Task<byte[]> ReadBytesAsync(
-        this BinaryReader reader,
-        int count,
-        CancellationToken cancellationToken = default
-    )
-    {
-        var buffer = new byte[count];
-        var bytesRead = await reader
-            .BaseStream.ReadAsync(buffer, 0, count, cancellationToken)
-            .ConfigureAwait(false);
-        if (bytesRead != count)
-        {
-            throw new EndOfStreamException();
-        }
-        return buffer;
-    }
 }

src/SharpCompress/Compressors/Xz/XZBlock.cs

@@ -132,7 +132,7 @@ public sealed class XZBlock : XZReadOnlyStream
         _paddingSkipped = true;
     }
 
-    private async Task SkipPaddingAsync(CancellationToken cancellationToken = default)
+    private async ValueTask SkipPaddingAsync(CancellationToken cancellationToken = default)
     {
         var bytes = (BaseStream.Position - _startPosition) % 4;
         if (bytes > 0)
@@ -158,7 +158,7 @@ public sealed class XZBlock : XZReadOnlyStream
         _crcChecked = true;
     }
 
-    private async Task CheckCrcAsync(CancellationToken cancellationToken = default)
+    private async ValueTask CheckCrcAsync(CancellationToken cancellationToken = default)
     {
         var crc = new byte[_checkSize];
         await BaseStream.ReadAsync(crc, 0, _checkSize, cancellationToken).ConfigureAwait(false);
@@ -194,7 +194,7 @@ public sealed class XZBlock : XZReadOnlyStream
         HeaderIsLoaded = true;
     }
 
-    private async Task LoadHeaderAsync(CancellationToken cancellationToken = default)
+    private async ValueTask LoadHeaderAsync(CancellationToken cancellationToken = default)
     {
         await ReadHeaderSizeAsync(cancellationToken).ConfigureAwait(false);
         var headerCache = await CacheHeaderAsync(cancellationToken).ConfigureAwait(false);
@@ -218,7 +218,7 @@ public sealed class XZBlock : XZReadOnlyStream
         }
     }
 
-    private async Task ReadHeaderSizeAsync(CancellationToken cancellationToken = default)
+    private async ValueTask ReadHeaderSizeAsync(CancellationToken cancellationToken = default)
     {
         var buffer = new byte[1];
         await BaseStream.ReadAsync(buffer, 0, 1, cancellationToken).ConfigureAwait(false);
@@ -249,7 +249,7 @@ public sealed class XZBlock : XZReadOnlyStream
         return blockHeaderWithoutCrc;
     }
 
-    private async Task<byte[]> CacheHeaderAsync(CancellationToken cancellationToken = default)
+    private async ValueTask<byte[]> CacheHeaderAsync(CancellationToken cancellationToken = default)
     {
         var blockHeaderWithoutCrc = new byte[BlockHeaderSize - 4];
         blockHeaderWithoutCrc[0] = _blockHeaderSizeByte;

src/SharpCompress/Compressors/Xz/XZFooter.cs

@@ -62,7 +62,7 @@ public class XZFooter
         }
     }
 
-    public async Task ProcessAsync(CancellationToken cancellationToken = default)
+    public async ValueTask ProcessAsync(CancellationToken cancellationToken = default)
     {
         var crc = await _reader
             .BaseStream.ReadLittleEndianUInt32Async(cancellationToken)

src/SharpCompress/Compressors/Xz/XZHeader.cs

@@ -41,7 +41,7 @@ public class XZHeader
         ProcessStreamFlags();
     }
 
-    public async Task ProcessAsync(CancellationToken cancellationToken = default)
+    public async ValueTask ProcessAsync(CancellationToken cancellationToken = default)
     {
         CheckMagicBytes(await _reader.ReadBytesAsync(6, cancellationToken).ConfigureAwait(false));
         await ProcessStreamFlagsAsync(cancellationToken).ConfigureAwait(false);
@@ -65,7 +65,7 @@ public class XZHeader
         }
     }
 
-    private async Task ProcessStreamFlagsAsync(CancellationToken cancellationToken = default)
+    private async ValueTask ProcessStreamFlagsAsync(CancellationToken cancellationToken = default)
     {
         var streamFlags = await _reader.ReadBytesAsync(2, cancellationToken).ConfigureAwait(false);
         var crc = await _reader

src/SharpCompress/Compressors/Xz/XZIndex.cs

@@ -41,7 +41,7 @@ public class XZIndex
         return index;
     }
 
-    public static async Task<XZIndex> FromStreamAsync(
+    public static async ValueTask<XZIndex> FromStreamAsync(
         Stream stream,
         bool indexMarkerAlreadyVerified,
         CancellationToken cancellationToken = default
@@ -71,7 +71,7 @@ public class XZIndex
         VerifyCrc32();
     }
 
-    public async Task ProcessAsync(CancellationToken cancellationToken = default)
+    public async ValueTask ProcessAsync(CancellationToken cancellationToken = default)
     {
         if (!_indexMarkerAlreadyVerified)
         {
@@ -100,7 +100,7 @@ public class XZIndex
         }
     }
 
-    private async Task VerifyIndexMarkerAsync(CancellationToken cancellationToken = default)
+    private async ValueTask VerifyIndexMarkerAsync(CancellationToken cancellationToken = default)
     {
         var marker = await _reader.ReadByteAsync(cancellationToken).ConfigureAwait(false);
         if (marker != 0)
@@ -122,7 +122,7 @@ public class XZIndex
         }
     }
 
-    private async Task SkipPaddingAsync(CancellationToken cancellationToken = default)
+    private async ValueTask SkipPaddingAsync(CancellationToken cancellationToken = default)
     {
         var bytes = (int)(_reader.BaseStream.Position - StreamStartPosition) % 4;
         if (bytes > 0)
@@ -143,7 +143,7 @@ public class XZIndex
         // TODO verify this matches
     }
 
-    private async Task VerifyCrc32Async(CancellationToken cancellationToken = default)
+    private async ValueTask VerifyCrc32Async(CancellationToken cancellationToken = default)
     {
         var crc = await _reader
             .BaseStream.ReadLittleEndianUInt32Async(cancellationToken)

src/SharpCompress/Compressors/Xz/XZStream.cs

@@ -142,7 +142,7 @@ public sealed class XZStream : XZReadOnlyStream, IStreamStack
         HeaderIsRead = true;
     }
 
-    private async Task ReadHeaderAsync(CancellationToken cancellationToken = default)
+    private async ValueTask ReadHeaderAsync(CancellationToken cancellationToken = default)
     {
         Header = await XZHeader
             .FromStreamAsync(BaseStream, cancellationToken)
@@ -153,7 +153,7 @@ public sealed class XZStream : XZReadOnlyStream, IStreamStack
 
     private void ReadIndex() => Index = XZIndex.FromStream(BaseStream, true);
 
-    private async Task ReadIndexAsync(CancellationToken cancellationToken = default) =>
+    private async ValueTask ReadIndexAsync(CancellationToken cancellationToken = default) =>
         Index = await XZIndex
             .FromStreamAsync(BaseStream, true, cancellationToken)
             .ConfigureAwait(false);
@@ -162,7 +162,7 @@ public sealed class XZStream : XZReadOnlyStream, IStreamStack
     private void ReadFooter() => Footer = XZFooter.FromStream(BaseStream);
 
     // TODO verify footer
-    private async Task ReadFooterAsync(CancellationToken cancellationToken = default) =>
+    private async ValueTask ReadFooterAsync(CancellationToken cancellationToken = default) =>
         Footer = await XZFooter
             .FromStreamAsync(BaseStream, cancellationToken)
             .ConfigureAwait(false);
@@ -202,7 +202,7 @@ public sealed class XZStream : XZReadOnlyStream, IStreamStack
         return bytesRead;
     }
 
-    private async Task<int> ReadBlocksAsync(
+    private async ValueTask<int> ReadBlocksAsync(
         byte[] buffer,
         int offset,
         int count,

src/SharpCompress/Compressors/ZStandard/CompressionStream.cs

@@ -77,7 +77,7 @@ public class CompressionStream : Stream
 #if !NETSTANDARD2_0 && !NETFRAMEWORK
     public override async ValueTask DisposeAsync()
 #else
-    public async Task DisposeAsync()
+    public async ValueTask DisposeAsync()
 #endif
     {
         if (compressor == null)
@@ -137,7 +137,7 @@ public class CompressionStream : Stream
 
     private void FlushInternal(ZSTD_EndDirective directive) => WriteInternal(null, directive);
 
-    private async Task FlushInternalAsync(
+    private async ValueTask FlushInternalAsync(
         ZSTD_EndDirective directive,
         CancellationToken cancellationToken = default
     ) => await WriteInternalAsync(null, directive, cancellationToken).ConfigureAwait(false);
@@ -183,7 +183,7 @@ public class CompressionStream : Stream
         CancellationToken cancellationToken = default
     )
 #else
-    private async Task WriteInternalAsync(
+    private async ValueTask WriteInternalAsync(
         ReadOnlyMemory<byte>? buffer,
         ZSTD_EndDirective directive,
         CancellationToken cancellationToken = default
@@ -235,14 +235,16 @@ public class CompressionStream : Stream
             .ConfigureAwait(false);
 #else
 
-    public override Task WriteAsync(
+    public override async Task WriteAsync(
         byte[] buffer,
         int offset,
         int count,
         CancellationToken cancellationToken
-    ) => WriteAsync(new ReadOnlyMemory<byte>(buffer, offset, count), cancellationToken);
+    ) =>
+        await WriteAsync(new ReadOnlyMemory<byte>(buffer, offset, count), cancellationToken)
+            .ConfigureAwait(false);
 
-    public async Task WriteAsync(
+    public async ValueTask WriteAsync(
         ReadOnlyMemory<byte> buffer,
         CancellationToken cancellationToken = default
     ) =>

src/SharpCompress/Compressors/ZStandard/DecompressionStream.cs

@@ -177,9 +177,9 @@ public class DecompressionStream : Stream
         int offset,
         int count,
         CancellationToken cancellationToken
-    ) => ReadAsync(new Memory<byte>(buffer, offset, count), cancellationToken);
+    ) => ReadAsync(new Memory<byte>(buffer, offset, count), cancellationToken).AsTask();
 
-    public async Task<int> ReadAsync(
+    public async ValueTask<int> ReadAsync(
         Memory<byte> buffer,
         CancellationToken cancellationToken = default
     )

src/SharpCompress/Factories/AceFactory.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Common.Ace.Headers;
@@ -26,12 +27,21 @@ namespace SharpCompress.Factories
             Stream stream,
             string? password = null,
             int bufferSize = ReaderOptions.DefaultBufferSize
-        )
-        {
-            return AceHeader.IsArchive(stream);
-        }
+        ) => AceHeader.IsArchive(stream);
 
         public IReader OpenReader(Stream stream, ReaderOptions? options) =>
             AceReader.Open(stream, options);
+
+        public ValueTask<IAsyncReader> OpenReaderAsync(
+            Stream stream,
+            ReaderOptions? options,
+            CancellationToken cancellationToken = default
+        ) => new(AceReader.Open(stream, options));
+
+        public override ValueTask<bool> IsArchiveAsync(
+            Stream stream,
+            string? password = null,
+            int bufferSize = ReaderOptions.DefaultBufferSize
+        ) => new(IsArchive(stream, password, bufferSize));
     }
 }

src/SharpCompress/Factories/ArcFactory.cs

@@ -4,6 +4,7 @@ using System.IO;
 using System.Linq;
 using System.Security.Cryptography;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Readers;
@@ -42,5 +43,17 @@ namespace SharpCompress.Factories
 
         public IReader OpenReader(Stream stream, ReaderOptions? options) =>
             ArcReader.Open(stream, options);
+
+        public ValueTask<IAsyncReader> OpenReaderAsync(
+            Stream stream,
+            ReaderOptions? options,
+            CancellationToken cancellationToken = default
+        ) => new(ArcReader.Open(stream, options));
+
+        public override ValueTask<bool> IsArchiveAsync(
+            Stream stream,
+            string? password = null,
+            int bufferSize = ReaderOptions.DefaultBufferSize
+        ) => new(IsArchive(stream, password, bufferSize));
     }
 }

src/SharpCompress/Factories/ArjFactory.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.Common.Arj.Headers;
@@ -33,5 +34,17 @@ namespace SharpCompress.Factories
 
         public IReader OpenReader(Stream stream, ReaderOptions? options) =>
             ArjReader.Open(stream, options);
+
+        public ValueTask<IAsyncReader> OpenReaderAsync(
+            Stream stream,
+            ReaderOptions? options,
+            CancellationToken cancellationToken = default
+        ) => new(ArjReader.Open(stream, options));
+
+        public override ValueTask<bool> IsArchiveAsync(
+            Stream stream,
+            string? password = null,
+            int bufferSize = ReaderOptions.DefaultBufferSize
+        ) => new(IsArchive(stream, password, bufferSize));
     }
 }

src/SharpCompress/Factories/Factory.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Common;
 using SharpCompress.IO;
 using SharpCompress.Readers;
@@ -57,6 +59,24 @@ public abstract class Factory : IFactory
         int bufferSize = ReaderOptions.DefaultBufferSize
     );
 
+    public abstract ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize
+    );
+
+    /// <inheritdoc/>
+    public virtual ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(IsArchive(stream, password, bufferSize));
+    }
+
     /// <inheritdoc/>
     public virtual FileInfo? GetFilePart(int index, FileInfo part1) => null;
 
@@ -92,4 +112,34 @@ public abstract class Factory : IFactory
 
         return false;
     }
+
+    internal virtual async ValueTask<(bool, IAsyncReader?)> TryOpenReaderAsync(
+        SharpCompressStream stream,
+        ReaderOptions options,
+        CancellationToken cancellationToken
+    )
+    {
+        if (this is IReaderFactory readerFactory)
+        {
+            long pos = ((IStreamStack)stream).GetPosition();
+
+            if (
+                await IsArchiveAsync(
+                    stream,
+                    options.Password,
+                    options.BufferSize,
+                    cancellationToken
+                )
+            )
+            {
+                ((IStreamStack)stream).StackSeek(pos);
+                return (
+                    true,
+                    await readerFactory.OpenReaderAsync(stream, options, cancellationToken)
+                );
+            }
+        }
+
+        return (false, null);
+    }
 }

src/SharpCompress/Factories/GZipFactory.cs

@@ -1,6 +1,8 @@
 using System.Collections.Generic;
 using System.IO;
 using System.IO.Compression;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Archives;
 using SharpCompress.Archives.GZip;
 using SharpCompress.Archives.Tar;
@@ -46,6 +48,14 @@ public class GZipFactory
         int bufferSize = ReaderOptions.DefaultBufferSize
     ) => GZipArchive.IsGZipFile(stream);
 
+    /// <inheritdoc/>
+    public override ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize,
+        CancellationToken cancellationToken = default
+    ) => GZipArchive.IsGZipFileAsync(stream, cancellationToken);
+
     #endregion
 
     #region IArchiveFactory
@@ -54,10 +64,30 @@ public class GZipFactory
     public IArchive Open(Stream stream, ReaderOptions? readerOptions = null) =>
         GZipArchive.Open(stream, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => GZipArchive.OpenAsync(stream, readerOptions, cancellationToken);
+
+    public override ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize
+    ) => new(IsArchive(stream, password, bufferSize));
+
     /// <inheritdoc/>
     public IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null) =>
         GZipArchive.Open(fileInfo, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => GZipArchive.OpenAsync(fileInfo, readerOptions, cancellationToken);
+
     #endregion
 
     #region IMultiArchiveFactory
@@ -66,10 +96,24 @@ public class GZipFactory
     public IArchive Open(IReadOnlyList<Stream> streams, ReaderOptions? readerOptions = null) =>
         GZipArchive.Open(streams, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => GZipArchive.OpenAsync(streams, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(IReadOnlyList<FileInfo> fileInfos, ReaderOptions? readerOptions = null) =>
         GZipArchive.Open(fileInfos, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => GZipArchive.OpenAsync(fileInfos, readerOptions, cancellationToken);
+
     #endregion
 
     #region IReaderFactory
@@ -108,6 +152,17 @@ public class GZipFactory
     public IReader OpenReader(Stream stream, ReaderOptions? options) =>
         GZipReader.Open(stream, options);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncReader> OpenReaderAsync(
+        Stream stream,
+        ReaderOptions? options,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(GZipReader.Open(stream, options));
+    }
+
     #endregion
 
     #region IWriterFactory
@@ -122,6 +177,17 @@ public class GZipFactory
         return new GZipWriter(stream, new GZipWriterOptions(writerOptions));
     }
 
+    /// <inheritdoc/>
+    public ValueTask<IWriter> OpenAsync(
+        Stream stream,
+        WriterOptions writerOptions,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, writerOptions));
+    }
+
     #endregion
 
     #region IWriteableArchiveFactory

src/SharpCompress/Factories/IFactory.cs

@@ -1,5 +1,7 @@
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Readers;
 
 namespace SharpCompress.Factories;
@@ -42,6 +44,20 @@ public interface IFactory
         int bufferSize = ReaderOptions.DefaultBufferSize
     );
 
+    /// <summary>
+    /// Returns true if the stream represents an archive of the format defined by this type asynchronously.
+    /// </summary>
+    /// <param name="stream">A stream, pointing to the beginning of the archive.</param>
+    /// <param name="password">optional password</param>
+    /// <param name="bufferSize">buffer size for reading</param>
+    /// <param name="cancellationToken">cancellation token</param>
+    ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize,
+        CancellationToken cancellationToken = default
+    );
+
     /// <summary>
     /// From a passed in archive (zip, rar, 7z, 001), return all parts.
     /// </summary>

src/SharpCompress/Factories/RarFactory.cs

@@ -1,5 +1,7 @@
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Archives;
 using SharpCompress.Archives.Rar;
 using SharpCompress.Common;
@@ -47,10 +49,30 @@ public class RarFactory : Factory, IArchiveFactory, IMultiArchiveFactory, IReade
     public IArchive Open(Stream stream, ReaderOptions? readerOptions = null) =>
         RarArchive.Open(stream, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => RarArchive.OpenAsync(stream, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null) =>
         RarArchive.Open(fileInfo, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => RarArchive.OpenAsync(fileInfo, readerOptions, cancellationToken);
+
+    public override ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize
+    ) => new(IsArchive(stream, password, bufferSize));
+
     #endregion
 
     #region IMultiArchiveFactory
@@ -59,10 +81,24 @@ public class RarFactory : Factory, IArchiveFactory, IMultiArchiveFactory, IReade
     public IArchive Open(IReadOnlyList<Stream> streams, ReaderOptions? readerOptions = null) =>
         RarArchive.Open(streams, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => RarArchive.OpenAsync(streams, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(IReadOnlyList<FileInfo> fileInfos, ReaderOptions? readerOptions = null) =>
         RarArchive.Open(fileInfos, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => RarArchive.OpenAsync(fileInfos, readerOptions, cancellationToken);
+
     #endregion
 
     #region IReaderFactory
@@ -71,5 +107,16 @@ public class RarFactory : Factory, IArchiveFactory, IMultiArchiveFactory, IReade
     public IReader OpenReader(Stream stream, ReaderOptions? options) =>
         RarReader.Open(stream, options);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncReader> OpenReaderAsync(
+        Stream stream,
+        ReaderOptions? options,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(RarReader.Open(stream, options));
+    }
+
     #endregion
 }

src/SharpCompress/Factories/SevenZipFactory.cs

@@ -1,5 +1,7 @@
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Archives;
 using SharpCompress.Archives.SevenZip;
 using SharpCompress.Common;
@@ -42,10 +44,30 @@ public class SevenZipFactory : Factory, IArchiveFactory, IMultiArchiveFactory
     public IArchive Open(Stream stream, ReaderOptions? readerOptions = null) =>
         SevenZipArchive.Open(stream, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => SevenZipArchive.OpenAsync(stream, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null) =>
         SevenZipArchive.Open(fileInfo, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => SevenZipArchive.OpenAsync(fileInfo, readerOptions, cancellationToken);
+
+    public override ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize
+    ) => new(IsArchive(stream, password, bufferSize));
+
     #endregion
 
     #region IMultiArchiveFactory
@@ -54,10 +76,24 @@ public class SevenZipFactory : Factory, IArchiveFactory, IMultiArchiveFactory
     public IArchive Open(IReadOnlyList<Stream> streams, ReaderOptions? readerOptions = null) =>
         SevenZipArchive.Open(streams, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => SevenZipArchive.OpenAsync(streams, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(IReadOnlyList<FileInfo> fileInfos, ReaderOptions? readerOptions = null) =>
         SevenZipArchive.Open(fileInfos, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => SevenZipArchive.OpenAsync(fileInfos, readerOptions, cancellationToken);
+
     #endregion
 
     #region reader

src/SharpCompress/Factories/TarFactory.cs

@@ -2,6 +2,8 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
 using SharpCompress.Archives;
 using SharpCompress.Archives.Tar;
 using SharpCompress.Common;
@@ -59,6 +61,12 @@ public class TarFactory
         int bufferSize = ReaderOptions.DefaultBufferSize
     ) => TarArchive.IsTarFile(stream);
 
+    public override ValueTask<bool> IsArchiveAsync(
+        Stream stream,
+        string? password = null,
+        int bufferSize = ReaderOptions.DefaultBufferSize
+    ) => new(IsArchive(stream, password, bufferSize));
+
     #endregion
 
     #region IArchiveFactory
@@ -67,10 +75,24 @@ public class TarFactory
     public IArchive Open(Stream stream, ReaderOptions? readerOptions = null) =>
         TarArchive.Open(stream, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        Stream stream,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => TarArchive.OpenAsync(stream, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null) =>
         TarArchive.Open(fileInfo, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        FileInfo fileInfo,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => TarArchive.OpenAsync(fileInfo, readerOptions, cancellationToken);
+
     #endregion
 
     #region IMultiArchiveFactory
@@ -79,10 +101,24 @@ public class TarFactory
     public IArchive Open(IReadOnlyList<Stream> streams, ReaderOptions? readerOptions = null) =>
         TarArchive.Open(streams, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<Stream> streams,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => TarArchive.OpenAsync(streams, readerOptions, cancellationToken);
+
     /// <inheritdoc/>
     public IArchive Open(IReadOnlyList<FileInfo> fileInfos, ReaderOptions? readerOptions = null) =>
         TarArchive.Open(fileInfos, readerOptions);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncArchive> OpenAsync(
+        IReadOnlyList<FileInfo> fileInfos,
+        ReaderOptions? readerOptions = null,
+        CancellationToken cancellationToken = default
+    ) => TarArchive.OpenAsync(fileInfos, readerOptions, cancellationToken);
+
     #endregion
 
     #region IReaderFactory
@@ -234,6 +270,17 @@ public class TarFactory
     public IReader OpenReader(Stream stream, ReaderOptions? options) =>
         TarReader.Open(stream, options);
 
+    /// <inheritdoc/>
+    public ValueTask<IAsyncReader> OpenReaderAsync(
+        Stream stream,
+        ReaderOptions? options,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(TarReader.Open(stream, options));
+    }
+
     #endregion
 
     #region IWriterFactory
@@ -242,6 +289,17 @@ public class TarFactory
     public IWriter Open(Stream stream, WriterOptions writerOptions) =>
         new TarWriter(stream, new TarWriterOptions(writerOptions));
 
+    /// <inheritdoc/>
+    public ValueTask<IWriter> OpenAsync(
+        Stream stream,
+        WriterOptions writerOptions,
+        CancellationToken cancellationToken = default
+    )
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+        return new(Open(stream, writerOptions));
+    }
+
     #endregion
 
     #region IWriteableArchiveFactory