He explains how nix/guix technology in the realm of personnal computing can improve day-to-day work, in this case the work of a developper. Wingo's setup is kind of complicated: nixos+guix. (I use only Guix OS for Django dev). In my case, Guix is overkill most of the time, since most dependencies are python. Guix can also replace virtualenv taking into account binary dependencies..

Binary dependency is the case met by Wingo.

I think he does not stress enough (first part) the fact that upgrading is painless in nixos and Guix OS (almost, it's still alpha) compared to debian-like distros.

Guix is a good idea. It needs more packages that is all.