I don't see a Nix example there, but the NixOS github looks to have some issues already surrounding provisioning Nix for use in containers.

Containers are a great way to explore a distro without messing with your host, you can at least check out their user space, filesystem layout, and package tooling. The main shortcoming is you don't get to see any kernel-specific features, since you're essentially chrooting into the other distro's rootfs.

There's always VMs too...