When upgrading Unity, the required Game-CI Docker images may not yet be available upstream. To unblock CI and local builds, we provide a GitHub Actions workflow that allows us to manually build and publish Unity editor images to our own GitHub Container Registry (GHCR) namespace.

This ensures we can continue upgrading Unity without waiting for official Game-CI images to be released.

Use this workflow when:

• Upgrading to a newer Unity version that is not yet available via Game-CI images
• CI tests.yml fails due to missing Unity editor Docker images

The workflow lives here:

https://github.com/decentraland/unity-explorer/actions/workflows/build-game-ci-image.yml

The workflow:

1. Clones the official game-ci/docker repository
2. Builds a Unity editor Docker image using the selected inputs
3. Tags the image following our internal naming convention
4. Pushes the image to GHCR under ghcr.io/decentraland

These images can then be referenced by CI jobs exactly like standard Game-CI images.

All images are published with the following format:

ghcr.io/decentraland/unityci-editor:<base_os>-<editor_version>-<target_platform>-<image_suffix>

Example:

ghcr.io/decentraland/unityci-editor:ubuntu-6000.2.14f1-linux-il2cpp-3.2.0

1. Go to Actions → Build GameCI Image
2. Click Run workflow
3. Fill in the inputs:

• Editor Version
  Unity editor version (e.g. 6000.2.14f1)

• Change Set
  Unity changeset hash for that editor version
  This must match the exact Unity release

• Base OS
  OS used for the Docker image
  Usually ubuntu

• Target Platform
  Unity module to install
  Common values:

  • linux-il2cpp
  • windows-il2cpp
  • mac-il2cpp
  • android
  • ios
  • webgl

• Image Tag Suffix
  Used to version or differentiate images
  Typically aligned with our internal Game-CI versioning

4. Run the workflow and wait for the image to build and push

The build runs on a custom runner: This is required due to:

• Large Docker image size
• Unity editor install requirements
• Build memory usage

Once built and pushed, re-running the failing tests.yml will now retrieve the image from the GHCR.