.NEXT

.NEXT (dotNext) is a set of powerful libraries aimed to improve development productivity and extend .NET API with unique features. Some of these features are planned in future releases of .NET platform but already implemented in the library:

Proposal	Implementation
Interop between function pointer and delegate	DelegateHelpers factory methods
Check if an instance of T is default(T)	IsDefault() method
Expression Trees covering additional language constructs, e.g. foreach, await, patterns, multi-line lambda expressions	Metaprogramming
Async Locks	Documentation
High-performance general purpose Write-Ahead Log	Persistent Log
Memory-mapped file as Memory<byte>	MemoryMappedFileExtensions
Memory-mapped file as ReadOnlySequence<byte>	ReadOnlySequenceAccessor
A dictionary where the keys are represented by generic arguments	Documentation
Process asynchronous tasks as they complete	Documentation
Soft References	Documentation

Quick overview of additional features:

• Attachment of user data to an arbitrary objects
• Extended set of atomic operations
• Fast conversion of bytes to hexadecimal representation and vice versa with Hex class
• ManualResetEvent, ReaderWriterLockSlim and other synchronization primitives now have their asynchronous versions
• Atomic memory access operations for arbitrary value types
• PipeExtensions provides high-level I/O operations for pipelines such as string encoding and decoding
• A rich set of high-performance memory buffers for efficient I/O
• String formatting, encoding and decoding with low GC pressure: dynamic char buffers
• Fully-featured Raft implementation
• Fully-featured HyParView implementation

All these things are implemented in 100% managed code on top of existing .NET API.

Quick Links

• Features
• API documentation
• Benchmarks
• NuGet Packages

What's new

Release Date: 08-19-2025

DotNext 5.24.0

• Merged 258
• Added CopyTo extension method overload for ReadOnlySequence<T> data type that returns the position within the sequence
• Fixed correctness of atomic read/write operations exposed by Atomic static class for double data type on 32-bit platforms
• LockAcquisition static methods are no longer extension methods to avoid ambiguity (see 267)

DotNext.Metaprogramming 5.24.0

• Updated dependencies

DotNext.Unsafe 5.24.0

• Added custom marshallers for IUnmanagedMemory<T> interface and Pointer<T> data type that are compatible with PInvoke source generator

DotNext.Threading 5.24.0

• AsyncLockAcquisition static methods are no longer extension methods to avoid ambiguity (see 267)
• Lock contention reported by all async lock primitives is now an up-down counter rather than regular counter

DotNext.IO 5.24.0

• Improved behavioral compatibility with Pipe class by extension methods exposed by PipeExtensions class

DotNext.Net.Cluster 5.24.0

• Added DotNext.Net.Multiplexing namespace that exposes simple unencrypted multiplexing protocol implementation on top of TCP. The multiplexed channel is exposed as IDuplexPipe. The main purpose of this implementation is the efficient communication between nodes within the cluster inside the trusted LAN

DotNext.AspNetCore.Cluster 5.24.0

• Updated dependencies

DotNext.MaintenanceServices 0.6.0

• Upgrade to newer System.CommandLine library
• Interactive session now prints > in the prompt
• Fixed buffer leak caused by interactive session

Changelog for previous versions located here.

Release & Support Policy

The libraries are versioned according to Semantic Versioning 2.0.

Version	.NET compatibility	Support Level
0.x	.NET Standard 2.0	❌
1.x	.NET Standard 2.0	❌
2.x	.NET Standard 2.1	❌
3.x	.NET Standard 2.1, .NET 5	❌
4.x	.NET 6	❌
5.x	.NET 8	✔️

❌ - unsupported, ✅ - bug and security fixes only, ✔️ - active development

Development Process

Philosophy of development process:

1. All libraries in .NEXT family are available for various .NET form factors: Mono, WASM, NativeAOT
2. Minimal set of dependencies
3. Provide high-quality documentation
4. Stay cross-platform
5. Provide benchmarks

Users

.NEXT is used by several companies in their projects:

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.

When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the .NET Foundation Code of Conduct. For more information see the Code of Conduct FAQ or contact conduct@dotnetfoundation.org with any additional questions or comments.