No network connectivity in virt-manager VMs

Hello, no matter what I do, there is no network connectivity in virtual machines created in virt-manager.

Host is NixOS Unstable and the VM is Debian 13, but network also doesn’t work in Linux Mint and Fedora VMs I spun up to test. For some reason, VMs work in Quickemu, so it isn’t a hardware issue, afaik. Network also works perfectly fine on the host.

Things I’ve tried:

  • Disabling the firewall
  • Switching firewall to nftables

My system config: crispyfires/.dotfiles: My .dotfiles for my NixOS setup. - Codeberg.org