Kotlin/JS application

Use the js/app product type in a module to build a JavaScript application using the Kotlin/JS technology. These applications can be run in browsers or Node.js.

Incomplete preview

The support for this product type is currently in an incomplete preview state.

For example, running a JavaScript application is not supported out of the box at the moment like other application types, and needs some manual work (see the Running your application).

We're eager to hear more about your use cases and how we can improve this experience! Please let us know in a YouTrack issue, or in our Slack channel.

Using IntelliJ IDEA?

Make sure to install the Kotlin Multiplatform plugin to get proper support for Kotlin/JS.

Module layout

Here is an overview of the module layout for a JavaScript application:

my-module/
├─ src/
│  ├─ main.kt
│  ╰─ Util.kt
├─ test/
│  ╰─ UtilTest.kt
╰─ module.yaml

Entry point

The entry point of a Kotlin/JS application is a top-level main function in the src folder.

Multiple main functions are not supported. If you have multiple main functions, the one chosen by the compiler as an entry point is unspecified.

Packaging

You can use the build command to compile your code to a JavaScript module file (.mjs) for your application. It cannot be run directly by Amper, but you can run it using Node.js or in a browser via an HTML page.

The .mjs file is produced in the build/tasks/_<module-name>_linkJs folder at the moment, but this is subject to change.

There is no extra packaging facilities at the moment, and the package command is not supported for this product type.

Running your application

Kotlin/JS applications cannot be run directly by Amper at the moment.

To run your application, you need to:

1. Install a JavaScript runtime (e.g., Node.js or a browser)
2. Build your module with ./amper build
3. Run the .mjs file produced by your module using your JavaScript runtime. See the Packaging section above to know where this file is located.