IMO for a graphical program that's fine, but in general I really hate hard requirements for a GPU which I've seen in the wild multiple times. Just simulate the darn thing in software, I don't care if it takes 10x longer, I have all the time in the world.

yes. it's working fine for me on 9 y/o integrated intel graphics.

but it's kind of still a weird statement to make. i thought it was generally the OS's job to supply the vulkan layer, and that mesa -- which just about every linux OS will be using -- provides pretty robust software implementations of those things as fallback. what would cause them to require a "physical" anything?