= Kotlin Multiplatform Library Template :toc: left :toclevels: 3 :source-highlighter: highlightjs :icons: font

A comprehensive template for creating Kotlin Multiplatform libraries with publishing to Maven Central.

== Overview

This template provides everything you need to build and publish a Kotlin Multiplatform library to Maven Central. It includes support for multiple platforms and comes pre-configured with modern development tools.

== Supported Platforms

This template supports the following platforms:

[cols="1,2", options="header"] |=== |Platform |Description |JVM |Java Virtual Machine applications, including Compose Desktop |Android |Android applications and libraries |Native |iOS applications |Web |JavaScript & WebAssembly applications |===

== Features

=== Kotlin Multiplatform Full Kotlin Multiplatform setup with support for a variety of targets.

=== Publishing to Maven Central Pre-configured publishing setup using the vanniktech Maven publish plugin with support for:

• Automatic signing with GPG keys
• Publishing to Sonatype Central Portal
• GitHub Actions integration for automated releases

=== Development Tools

[cols="1,1,2", options="header"] |=== |Tool |Version |Purpose |Kotlinter |Latest |Kotlin linting and code formatting |Dokka |Latest |API documentation generation |Kermit |Latest |Multiplatform logging library |===

=== Project Configuration Centralized configuration using gradle.properties for easy customization:

• Developer information
• Repository details
• Publishing coordinates
• Library metadata

== Getting Started

=== Prerequisites

• JDK 11 or higher
• Gradle 8.0 or higher
• Xcode (for iOS development, macOS only)

=== Setup

1. Clone this template repository

2. Update the gradle.properties file with your information:

   • Change user, dev, mail, devURL to your details
   • Update repo, g, artifact, desc for your library
   • Set the initial version v

3. Rename the library module if desired

4. Start developing your library in the library/src directory

=== Building

To build the library for all platforms:

To run tests on all platforms:

To generate documentation:

== Publishing to Maven Central

This template uses a similar packaging secret method as other Malefic projects, making it easy to set up automated publishing.

For publishing to work, the following GitHub secrets must be configured in your repository:

• GPG_KEY_ID: The ID of your GPG key
• GPG_PASSPHRASE: The passphrase for your GPG key
• GPG_PRIVATE_KEY: Your GPG private key
• SONATYPE_TOKEN_XML: Your Sonatype Central Portal user token in XML format ====

=== Setting Up Secrets

==== GPG Key Setup

1. Generate a GPG key pair: [source,bash]

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2. Export your private key: [source,bash]

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3. Get your key ID: [source,bash]

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4. Upload your public key to a keyserver: [source,bash]

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==== Sonatype Setup

1. Create an account on https://central.sonatype.com/
2. Register your namespace (e.g., io.github.yourusername)
3. Generate a user token from the Account page
4. Copy the XML token block for the GitHub secret

=== Publishing Process

The template includes a GitHub Actions workflow that automatically publishes releases:

1. Create a new release on GitHub
2. The workflow will automatically build and publish to Maven Central
3. Artifacts will be available after Sonatype review (usually 15-30 minutes)

To publish manually:

== Project Structure

== Configuration

All project configuration is centralized in gradle.properties:

user=YourGitHubUsername dev=Your Full Name mail=your.email@example.com devURL=https://your-website.com

repo=YourRepositoryName g=your.group.id artifact=your-artifact-name desc=Your library description inception=2025

== Example Usage

The template includes a simple Fibonacci sequence generator as an example. Replace this with your own library code:

// Common code fun generateFibi() = sequence { var a = firstElement yield(a) var b = secondElement yield(b) while (true) { val c = a + b yield(c) a = b b = c } }

expect val firstElement: Int expect val secondElement: Int

== License

This template is licensed under the MIT License. Update the LICENSE file with your chosen license.

== Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests for new functionality
5. Submit a pull request

== Resources

• https://kotlinlang.org/docs/multiplatform.html[Kotlin Multiplatform Documentation]
• https://central.sonatype.org/[Maven Central Portal]
• https://vanniktech.github.io/gradle-maven-publish-plugin/[Vanniktech Maven Publish Plugin]
• https://github.com/touchlab/Kermit[Kermit Logging Library]