There seems to be development of a declarative and idempotent process for building Incus environments on NixOS:
https://wiki.nixos.org/wiki/Incus
Another link describing a NixOS and Incus pairing as synergistic:
It would be great to see Incus become a truly developer friendly virtualisation platform competitive with the likes of Podman, Distrobox, Toolbx and Vagrant.
I’m looking at Ivan Pepelnjak’s Netlab and it uses KVM/libvirt with Vagrant but cannot support LXC or Docker based network appliances unless separate solutions are built using Containerlab or Docker:
https://netlab.tools/
Incus would be a great fit for Netlab if an IncusFile for declarative builds was possible.
Incus + Netlab — no need for juggling kvm-libvirt-vagrant-docker-containerlab environments to support different network appliances:
https://netlab.tools/platforms/
NixOS seems like a great platform to implement a declarative Incus until such time as it becomes a native capability in Incus.