kotlin-native-nuget

Build plugin publishing native libraries as NuGet packages, auto-generating C# bindings and reverse bindings, shipping a fixed-ABI runtime, and providing a configurable bind DSL.

#windows
#native
#macos
#kotlin-native
#kotlin-dsl
#kotlin-coroutines
#gradle-plugin
#code-generation

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macOS

Linux

Windows

GitHub stars24

Authorsxxfast

Dependents0

LicenseApache License 2.0

Creation date4 months ago

Last activityabout 11 hours ago

Latest release0.7.0 (14 days ago)

Homepage GitHub repository GitHub pages

kotlin-native-nuget

A plugin that allows you to publish your Kotlin/Native libraries as NuGet packages to be consumed by .NET projects.

Background

https://www.youtube.com/watch?v=DywUS-qYn6o

Read the announcement: Bring your KMP library to NuGet

Stability

0.x and experimental. Anything can change between versions.

The generated bindings are the public API of your NuGet package. Your consumers see your version, never the plugin's. A plugin upgrade that changes how Kotlin renders into C# breaks them at your version, not ours.

Pin the plugin version. Diff the generated Interop.cs when you bump it.

Setup

// build.gradle.kts
plugins {
  kotlin("multiplatform")
  id("io.github.xxfast.kotlin.native.nuget") version "<version>"
}

kotlin {
  mingwX64 { binaries { sharedLib { baseName = "mycatlib" } } }
  macosArm64 { binaries { sharedLib { baseName = "mycatlib" } } }
}

nuget {
  publish {
    packageId = "MyCatLib"
    version = "1.0.0"
    authors = "yourname"
    description = "My Kotlin/Native library"
    rootPackage = "com.example.cats"
  }
}

Applying the plugin also adds nuget-runtime, a small Kotlin/Native library carrying the fixed nuget_* ABI (handles, errors, collections, callbacks, coroutines), as a dependency and exports it into your shared library; you never reference it yourself. It's the project's first published artifact that's a real klib rather than a JVM jar, which makes it indexable on klibs.io. See ADR-127.

Usage

Kotlin → C#

// Kotlin
interface Pet { val name: String; fun speak(): String }
enum class Mood { HAPPY, SLEEPY, GRUMPY }
abstract class Animal(override val name: String) : Pet

class Cat(name: String, val lives: Int = 9) : Animal(name) {
  var brother: Cat? = null
  var mood: Mood = Mood.SLEEPY
  val toys: List<Toy> = listOf(Toy("Mouse", "Gray"))
  val onMeow: () -> String = { "Meow! My name is $name" }
  override fun speak(): String = "Meow!"
}

data class Toy(val name: String, val color: String)
class Box<T>(val item: T)
fun owner(name: String): String? = if (name == "Oreo") "Isuru" else null

// C# (auto-generated)
using var oreo = new Cat("Oreo", 9);

oreo.Name;                                  // "Oreo"
oreo.Speak();                               // "Meow!"
oreo.Brother = new Cat("Mylo", 9);          // nullable object setter
oreo.Mood = Mood.Happy;                     // enums

using var toy = new Toy("Mouse", "Gray");
toy.ToString();                             // "Toy(name=Mouse, color=Gray)"
toy.Equals(toy.Copy("Ball", "Red"));        // data class equality + copy

IReadOnlyList<Toy> toys = oreo.Toys;        // collections
using var box = new Box<string>("hello");    // generics
string? owner = CatKt.Owner("Oreo");        // nullable returns

using var onMeow = oreo.OnMeow;
onMeow.Invoke();                            // lambdas

IPet pet = oreo;                            // interface polymorphism
Animal animal = oreo;                       // abstract class hierarchy

By default the processor bridges every public declaration it can see in the module, not just the ones under rootPackage. rootPackage only names the generated C# namespace. If your module has unrelated public API, scope it with publish { include(...); exclude(...) }.

Not everything bridges. The forward direction has a defined bridgeable subset; declarations outside it are skipped with a named diagnostic rather than silently dropped or miscompiled. See Publishing Kotlin to C# for the full mapping and its limits.

C# -> Kotlin

public class Template
{
    public Template(string template) { ... }  // constructor
    public string Name { get; set; }          // instance property
    public string Apply(string name) { ... }  // instance method
    public static Template Parse(string template) { ... } // static method
    public void Use(Action<Template> action) { ... }      // IDisposable pattern
    public static string Render(Template template, string name) { ... } // static method
}

// build.gradle.kts
nuget {
  dependencies {
    dependency("TestDependency", version = "1.0.0") {
      bind {
        include("Test.Text")               // C# namespaces to bind
        alias("Test.Text", "sample.text")  // C# namespace to Kotlin package
      }
    }
  }
}

// Kotlin (auto-generated)
val template = Template("Hello, {name}")       // constructor
template.name = "Oreo"                         // instance property
template.apply("Oreo")                         // instance method
Template.parse("Hello, {name}")                // static -> companion object
template.use { Template.render(it, "Oreo") }   // handles are AutoCloseable

Documentation

Full docs: xxfast.github.io/kotlin-native-nuget

Prerequisites and the version compatibility table
Getting started
Publishing Kotlin to C#: every construct that crosses, page by page
Consuming C# in Kotlin: the bind {} DSL and what binds today
Gradle tasks and the nuget {} DSL reference

[!TIP] See the architecture overview for how the bridge is built, ROADMAP.md for what's next, and docs/adr/ for the architecture decision records.

macOS

Linux

Windows

GitHub stars24

Authorsxxfast

Dependents0

LicenseApache License 2.0

Creation date4 months ago

Last activityabout 11 hours ago

Latest release0.7.0 (14 days ago)

Homepage GitHub repository GitHub pages

kotlin-native-nuget

A plugin that allows you to publish your Kotlin/Native libraries as NuGet packages to be consumed by .NET projects.

Background

https://www.youtube.com/watch?v=DywUS-qYn6o

Read the announcement: Bring your KMP library to NuGet

Stability

0.x and experimental. Anything can change between versions.

Pin the plugin version. Diff the generated Interop.cs when you bump it.

Setup

// build.gradle.kts
plugins {
  kotlin("multiplatform")
  id("io.github.xxfast.kotlin.native.nuget") version "<version>"
}

kotlin {
  mingwX64 { binaries { sharedLib { baseName = "mycatlib" } } }
  macosArm64 { binaries { sharedLib { baseName = "mycatlib" } } }
}

nuget {
  publish {
    packageId = "MyCatLib"
    version = "1.0.0"
    authors = "yourname"
    description = "My Kotlin/Native library"
    rootPackage = "com.example.cats"
  }
}

Usage

Kotlin → C#

// Kotlin
interface Pet { val name: String; fun speak(): String }
enum class Mood { HAPPY, SLEEPY, GRUMPY }
abstract class Animal(override val name: String) : Pet

class Cat(name: String, val lives: Int = 9) : Animal(name) {
  var brother: Cat? = null
  var mood: Mood = Mood.SLEEPY
  val toys: List<Toy> = listOf(Toy("Mouse", "Gray"))
  val onMeow: () -> String = { "Meow! My name is $name" }
  override fun speak(): String = "Meow!"
}

data class Toy(val name: String, val color: String)
class Box<T>(val item: T)
fun owner(name: String): String? = if (name == "Oreo") "Isuru" else null

// C# (auto-generated)
using var oreo = new Cat("Oreo", 9);

oreo.Name;                                  // "Oreo"
oreo.Speak();                               // "Meow!"
oreo.Brother = new Cat("Mylo", 9);          // nullable object setter
oreo.Mood = Mood.Happy;                     // enums

using var toy = new Toy("Mouse", "Gray");
toy.ToString();                             // "Toy(name=Mouse, color=Gray)"
toy.Equals(toy.Copy("Ball", "Red"));        // data class equality + copy

IReadOnlyList<Toy> toys = oreo.Toys;        // collections
using var box = new Box<string>("hello");    // generics
string? owner = CatKt.Owner("Oreo");        // nullable returns

using var onMeow = oreo.OnMeow;
onMeow.Invoke();                            // lambdas

IPet pet = oreo;                            // interface polymorphism
Animal animal = oreo;                       // abstract class hierarchy

C# -> Kotlin

public class Template
{
    public Template(string template) { ... }  // constructor
    public string Name { get; set; }          // instance property
    public string Apply(string name) { ... }  // instance method
    public static Template Parse(string template) { ... } // static method
    public void Use(Action<Template> action) { ... }      // IDisposable pattern
    public static string Render(Template template, string name) { ... } // static method
}

// build.gradle.kts
nuget {
  dependencies {
    dependency("TestDependency", version = "1.0.0") {
      bind {
        include("Test.Text")               // C# namespaces to bind
        alias("Test.Text", "sample.text")  // C# namespace to Kotlin package
      }
    }
  }
}

// Kotlin (auto-generated)
val template = Template("Hello, {name}")       // constructor
template.name = "Oreo"                         // instance property
template.apply("Oreo")                         // instance method
Template.parse("Hello, {name}")                // static -> companion object
template.use { Template.render(it, "Oreo") }   // handles are AutoCloseable

Documentation

Full docs: xxfast.github.io/kotlin-native-nuget

Prerequisites and the version compatibility table
Getting started
Publishing Kotlin to C#: every construct that crosses, page by page
Consuming C# in Kotlin: the bind {} DSL and what binds today
Gradle tasks and the nuget {} DSL reference

[!TIP] See the architecture overview for how the bridge is built, ROADMAP.md for what's next, and docs/adr/ for the architecture decision records.