I tried to use it right after launch from within Claude Desktop, on a Mac VM running within UTM, and got cryptoc messages about Apple virtualization framework.
That made me realize it wants to also run a Apple virtualization VM but can’t since it’s inside one already - imo the error messaging here could be better, or considering that it already is in a VM, it could perhaps bypass the vm altogether. Because right now I still never got to try cowork because of this error.
Does UTM/Apple's framework not allow nested virtualization? If I remember correctly from x86(_64) times, this is a thing that sometimes needs to be manually enabled.
I've come across two different answers regarding Apple's Virtualization.Framework support for nested virtualization:
1. Yes, but only Linux guests 2. Yes, but only M3+
You are correct on both accounts, as of tahoe 26.3 you can't nest a macOS guest under a macOS guest. However you can nest 2 layers deep with any combo of layer 1 guest so long as the machine is running Sequoia and is M3/M4/M5.