Chapter 6. SecurityNix has two basic security models. First, it can be used in “single-user mode”, which is similar to what most other package management tools do: there is a single user (typically root) who performs all package management operations. All other users can then use the installed packages, but they cannot perform package management operations themselves.Alternatively, you can configure Nix in “multi-user mode”. In this model, all users can perform package management operations — for instance, every user can install software without requiring root privileges. Nix ensures that this is secure. For instance, it’s not possible for one user to overwrite a package used by another user with a Trojan horse.
Would have been nice to link these to the install chapter where single- and multi-user modes were mentioned.
How would this look in a topic-based documentation? I would think that his chapter would be listed in the pre-requisites, and it could be used to buld different reading paths (or assemblies in DocBook, I believe) such as practical, depth-first (if there are people like me who want to understand everything first), etc.