Hi Guido,
I wonder why the manager did start my vm-nixos when part_blk became available but decided to kill it when the inspector closes. It knows there is a dependency.
init restarts a component whenever any of the component's existing session routes change. This is to enforce the new routing policy.
In your scenario, 'vm-nixos' had a block session routed to 'ahci-1.part_blk'. When you closed the inspect window, the sculpt manager decided to remove the 'ahci-1.part_blk' because it was solely needed to support the inspect window. This removal, in turn, invalidated the block-session route of 'vm-nixos', which prompted the runtime's init to restart the 'vm-nixos' component. The restarted version, however, could not establish its block-session route. So it got stuck at this point.
In short, the Sculpt manager did not affect the 'vm-nixos' directly. The observed killing was actually a restart, indirectly caused by the removal of the 'ahci-1.part_blk'.
Bummer, I had in mind to dedicate that secondary partition to the vm-nixos with a policy and leave the rest to Sculpt.
We will get there. But we are not there yet. ;-)
Cheers Norman