Can not upgrade multimodule addon project

I have a multi-module project that contains my addons. The structure from this project is taken by looking at the jmix codebase itself.

I tried upgrading this project for the first time.

I wanted to go from 2.7.4 to 2.8.3 but it doesn’t work. the moment the popup with the changes is shown and i click on “migrate“ the pop up closes but nothing happens.

I tried to do the same thing upgrading only a minor version, same problem.

the exception is (log file in attachment)

2026-06-09 21:11:15,594 [ 416016] SEVERE - #c.i.i.p.PluginManager - Illegal char <:> at index 15: octorilla-async:octorilla-async-starter
java.nio.file.InvalidPathException: Illegal char <:> at index 15: octorilla-async:octorilla-async-starter

upgrading issue.txt (63.4 KB)

Hi Tom,

It seems that your multi-module project structure is not supported by Jmix Studio, so the migration cannot be performed automatically.

Jmix Studio currently supports only composite projects that contain multiple add-on and application subprojects. Please see the documentation for details:

https://docs.jmix.io/jmix/studio/composite-projects.html

In your case, you can try opening each subproject as a separate Gradle project and migrating them one by one.

Alternatively, you can perform the migration manually. Please refer to the “What’s New” page for Jmix 2.8, or run the migration in Studio on a compatible sample project and review the changes that Studio applies automatically.

is the application subproject necessary? my setup should be a valid multi-module project with addons (but no application)

I ended up creating a new multimodule project and copying all sources, took some time but at least I have a fully compatible setup now