WACS.HostBindings.Abstractions 0.3.0

.NET 8.0 This package targets .NET 8.0. The package is compatible with this framework or higher. .NET Standard 2.0 This package targets .NET Standard 2.0. The package is compatible with this framework or higher. 
dotnet add package WACS.HostBindings.Abstractions --version 0.3.0
                    


                    

                
NuGet\Install-Package WACS.HostBindings.Abstractions -Version 0.3.0
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package. 
<PackageReference Include="WACS.HostBindings.Abstractions" Version="0.3.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package. 
<PackageVersion Include="WACS.HostBindings.Abstractions" Version="0.3.0" />
                    


                            Directory.Packages.props
                        

                    

                
<PackageReference Include="WACS.HostBindings.Abstractions" />
                    


                            Project file
For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package. 
paket add WACS.HostBindings.Abstractions --version 0.3.0
                    


                    

                
#r "nuget: WACS.HostBindings.Abstractions, 0.3.0"
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package. 
#:package WACS.HostBindings.Abstractions@0.3.0
#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package. 
#addin nuget:?package=WACS.HostBindings.Abstractions&version=0.3.0
                    


                            Install as a Cake Addin
                        

                    

                
#tool nuget:?package=WACS.HostBindings.Abstractions&version=0.3.0
                    


                            Install as a Cake Tool

WACS.HostBindings.Abstractions

The shared vocabulary for WACS host bindings. Exposes:

  • [WacsImport(string module, string name)] — annotate a static method as the implementation of a wasm import. Consumed by WACS.HostBindings.SourceGen at consumer build time.
  • [WacsImportNames(string mapping)] — assembly-level mapping for save-to-dll outputs whose method-level attributes don't survive the PE serializer.
  • [WacsTranspiledImports] — marks a generated imports type for the transpiler's source-gen pickup.
  • [WasmName(string)] — round-trips the original wasm name (e.g. wasi:cli/run@0.2.0#run) on auto-generated IExports / IImports methods whose CLR identifier got sanitized (wasi_cli_run_0_2_0_run). Stamped automatically by the WACS interface generator; consumers reflect on it for dispatch and diagnostics.
  • [assembly: WasiHostPackage(string? label)] — assembly-level marker flagging an assembly as a WACS host package — discoverable by runtime.AutoDiscoverHostPackages(). Pairs with the explicit-list runtime.UseHostPackages(name1, name2, …).
  • WacsHostMemory — a 16-byte readonly struct view over wasm linear memory, passed as the first parameter to every binding method. Bounds-checked accessors plus an AsSpan escape hatch for bulk I/O.
  • WacsHostFault — exception type for binding-side traps. Surfaced as a wasm runtime fault by the caller.

Tiny by design. No runtime allocations, AOT-clean, netstandard2.0 so the matching Roslyn source generator can reference it directly.

Authoring a host binding

public static class MyEngineBindings
{
    [WacsImport("game_engine", "log")]
    public static void Log(WacsHostMemory mem, int strPtr, int strLen)
    {
        var span = mem.AsSpan(strPtr, strLen);
        Console.WriteLine(System.Text.Encoding.UTF8.GetString(span));
    }

    [WacsImport("game_engine", "rand")]
    public static int Rand(WacsHostMemory mem, int max)
        => Random.Shared.Next(max);
}

The first parameter is always WacsHostMemory (host code may need it). Subsequent parameters match the wasm import's typed signature.

Per-call shared state

Bindings that need long-lived state (file descriptors, configuration, etc.) take a state parameter as the second argument:

public static class WasiPreview1Bindings
{
    [WacsImport("wasi_snapshot_preview1", "fd_write")]
    public static int FdWrite(WacsHostMemory mem, State state,
                              int fd, int iovs, int iovs_len, int nwritten)
    {
        // … implementation backed by `state.FileDescriptors[fd]`
    }
}

The source generator detects state-typed parameters via type identity and threads them through from a constructor on GeneratedHostImports. Multiple bindings sharing the same state type share the same constructor parameter.

Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 was computed.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 is compatible.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed.  net9.0 was computed.  net9.0-android was computed.  net9.0-browser was computed.  net9.0-ios was computed.  net9.0-maccatalyst was computed.  net9.0-macos was computed.  net9.0-tvos was computed.  net9.0-windows was computed.  net10.0 was computed.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-windows was computed. 
.NET Core netcoreapp2.0 was computed.  netcoreapp2.1 was computed.  netcoreapp2.2 was computed.  netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.0 is compatible.  netstandard2.1 was computed. 
.NET Framework net461 was computed.  net462 was computed.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen40 was computed.  tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

  • .NETStandard 2.0

  • net8.0

    • No dependencies.

NuGet packages (6)

Showing the top 5 NuGet packages that depend on WACS.HostBindings.Abstractions:

Package Downloads
WACS.WASI.NN

WASI-NN host bindings for WACS — wasi:nn@0.2.0-rc-2024-10-28 (component-model WIT) plus the legacy wasi_ephemeral_nn (WITX) ABI. Backend-agnostic core; pluggable backends (ML.NET, ONNX Runtime, ONNX Runtime GenAI, LlamaSharp, TorchSharp, OpenVINO) ship as sibling packages. Tracks the wasi-nn proposal at WASI Phase 2 — the WIT surface may change as the proposal evolves.
WACS.Transpiler.Lib

Library API for WACS.Transpiler — programmatic ahead-of-time WebAssembly-to-.NET IL transpilation, plus seamless loading of saved transpiled assemblies. v0.7.2 fixes a re-instantiation bug where Module classes with active data segments would come up zeroed on the second `Activator.CreateInstance` because spec §4.5.4 segment-drop emptied the process-wide ModuleInit registry. Module ctors now restore from `ModuleInitData.SavedDataSegments` before each CopyDataSegment so every fresh instance sees its memory initialized. v0.7 retires Lokad.ILPack for PersistedAssemblyBuilder (.NET 9), moves WASM data segments + the codec blob to RVA-mapped initialized data (62.5% smaller than the prior base64-in-#US path, true zero-copy from PE pages to ModuleInitData via UnmanagedMemoryStream), and introduces EmissionTarget.Auto as the new default — promotes to AotLinked when the module fits a conservative envelope (compute / memory / globals / tables + active+passive segments / multi-memory / local tags / imported functions), falling back to Standard otherwise. ~50% first-trial cold-start cut on promoted modules. ImportDispatcher now throws on missing handlers by default (lenient: true opts out). v0.6 consumed the Branch Hinting proposal's metadata.code.branch_hint custom section. v0.5 added the AotLinked emission target, stable AssemblyName, and the [WacsTranspiledImports] / [WacsImportNames] emission used by WACS.HostBindings.SourceGen.
WACS.WASI.Preview1

WASI Preview 1 implementation for WACS. Successor to the deprecated WACS.WASIp1 package; identical API under the new Wacs.WASI.Preview1 namespace. C# `TypeForwardedTo` cannot bridge a namespace rename, so the deprecated WACS.WASIp1 package is now a metapackage that pulls this assembly in transitively while consumers update their `using Wacs.WASIp1;` lines to `using Wacs.WASI.Preview1;` (one-shot sed in docs/MIGRATION_WASIp1_to_WASI.md). v0.12.0 lifts 23 wasi-testsuite fixtures (Phase 4): symlink behavior modes (no-follow lstat, dangling-target unlink, ELOOP on path_open), trailing-slash semantics, fd_readdir . / .., directory FD own-vs-inherited rights split, real Unix st_ino via stat(2), Clock.ToDateTimeUtc nanosecond fix, plus errno tightening (BADF for invalid fds, ENOTDIR / ISDIR / PERM in path_open). 67/72 fixtures pass; remaining 5 are OS-API-specific (lutimes, rename(2)) or runtime-quirk.
WACS.WASI.Threads

wasi-threads host-import adapter for WACS. Binds `wasi:thread-spawn` onto the core IWasmThreadHost primitive so wasm modules with shared memory can spawn worker threads.
WACS.WASI.GFX

WASI-GFX host bindings for WACS — wasi:graphics-context, wasi:frame-buffer, wasi:surface (all @0.0.1). Backend-agnostic core; the Silk.NET/SDL backend ships as a sibling package. Preview: tracks the wasi-gfx proposal at WASI Phase 2 — the WIT surface may change as the proposal evolves.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last Updated
0.3.0 1,209 5/10/2026
0.1.0 273 5/1/2026