I deem that you are correct! I have investigated NixOS in a Vagrant + Virtualbox combo very similar to what I did in this post, and yes, this is a much more det

I deem that you are correct! I have investigated NixOS in a Vagrant + Virtualbox combo very similar to what I did in this post, and yes, this is a much more deterministic solution to this idea. If the people you are writing a tutorial for can be expected to be familiar with Nix, this is probably a much more future-proofed solution. That's still a small camp of people at the moment, but it does include the creator of Vagrant himself, Mitchell Hashimoto. I maintain that a specific Debian version is a better "lingua franca" for a general audience - that may change in coming years, of course. I have begun writing a new tutorial called "NixOS: Three Big Ideas" to expose people like myself who haven't given Nix the time of day to explore its concepts in about 20 minutes or so.