Standalone and Split Mode

RakuOS ships a read only base image, with anything you install layered on top in an overlay. Rum is aware of this and automatically detects which mode it should run in, you never need to choose it yourself.

Split mode

On a real RakuOS system with an active overlay, rum runs in Split mode. It keeps its own overlay only package database, separate from the base image's package database, and every install, remove, or upgrade acts only on the overlay. The read only base image is never modified. If you name a package that's already part of the base image on rum upgrade, rum reports it rather than layering a duplicate copy on top.

Standalone mode

Everywhere else, a Distrobox or Podman container, or an image build environment, rum runs in Standalone mode. There's no base and overlay split here, rum behaves like a normal package manager working against a single package database, whether that's the system default or a path given with --installroot.

Checking your mode

Run the following to see which mode rum has detected and the paths it's using:

rum paths

To check whether a specific installed package comes from the base image or the overlay, use:

rum origin <package-name>

Why some commands add --nodeps automatically

In Split mode, and whenever --installroot is used, rpm's dependency checker can only see one half of the full package set at a time, the overlay or the alternate root, not both. Rum silently adds --nodeps in these cases so rpm doesn't wrongly flag packages as broken. You don't need to pass this yourself.