I don't know if it's useful to you, but I can link you to Eelco Dolstra’s PhD Thesis (2006):

http://nixos.org/~eelco/pubs/phd-thesis.pdf

He also wrote this InfoQ article on the subject of Nix and NixOS which may have some useful information (2014):

https://www.infoq.com/articles/configuration-management-with...

The Wikipedia pages for Nix and NixOS also have some interesting references.

https://en.wikipedia.org/wiki/NixOS

https://en.wikipedia.org/wiki/Nix_package_manager

Edit: I have been playing with NixOS at home for a few months and I think it's very interesting, but I'm a bit surprised I haven't heard more about it over the past decade or so. I'm thinking that the recent industry focus on deployments and provisioning has caused more people to come across it.