I tried building the ISO with nix-build nixos/release-combined.nix -A nixos.iso_graphical.x86_64-linux and then testing it with qemu-system-x86_64 -cdrom result/iso/nixos-graphical-25.05pre56789.gfedcba-x86_64-linux.iso -m 2048 -smp 4. The installer loads but cannot start because the module partition@partition cannot be loaded - presumably because my virtual machine has no disks.

OK, the partition@partition was in fact a problem with the packaging, now fixed. Testing with:

$ qemu-img create /path/to/foo.qcow2 40G
$ nix-build nixos/release-combined.nix -A nixos.iso_graphical.x86_64-linux
$ qemu-system-x86_64 -cdrom result/iso/nixos-graphical-*.iso -m 4096 -smp 8 -drive file=/path/to/foo.qcow2
(select 'Plasma')

I see some smaller problems:

• The warning/error icons for unsafe passwords look bad
• I cannot switch to an earlier phase using the menu on the left, only with the previous/next buttons
• The step where I select whether to include LibreOffice, not include LibreOffice or perform a minimal install is in the 'Unfree Software' category, which seems odd.
• The 'overview' page at the end was too big for the size of the window, I had to manually maximize the window to be able to continue

I haven't checked if those problems were already there earlier, to me they don't feel like showstoppers for dropping qt5 tbh. This produced a system that I could boot into just fine with:

$ qemu-system-x86_64 -m 4096 -smp 8 -drive file=/path/to/foo.qcow2

Thank you very much for having a look!

OK, so it'd be good to zoom in on 0004-Adds-unfree-qml-to-packagechooserq.patch and see what might be going on there. To set expectations, I'm not sure if I'll find time to look into this soon.

This is in fact a showstopper because the buttons in this UI will not do anything

Ah, right, that doesn't make sense then

and we lose the ability to allow unfree software

(fwiw I'd personally be OK with that being a manual step after installation, but I suppose that's my bias showing 😄)

The QML in the calamares-nixos-extensions repo needs porting to Qt 6. There’s examples of a Qt 5 and Qt 6 extension page thingy in the Calamares repository that you could use for reference. I was working on this to reduce ISO closure size but I got bored. You might want to take a look at https://github.com/emilazy/nixpkgs/commits/push-zkkxlquwrylt, which contains additional changes compared to this PR; feel free to reuse my commits.

Fixed the 0004-Adds-unfree-qml-to-packagechooserq.patch so the 'Unfree Software' page works on qt6

The QML in the calamares-nixos-extensions repo needs porting to Qt 6.

Is there anything in particular that needs porting? I'm not very familiar with QML but I don't see anything particularly wrong?

no longer needed since #430636 is in