Nix is completely orthogonal to whatever tech you use to build the resume - it's nice as a build tool + to provide dev environments for however you're going to realize your resume.
Nix ≠ NixOS. Nix is a build tool (like make or Ninja or Bazel) with strict isolation of builds and caching of artifacts. NixOS is a distro built on top of that tool, like the BSDs are built on top of make, Gentoo on top of Portage, or gittup[1] on top of tup. Running NixOS while you’re building your resume is irrelevant; using Nix to create the final artifacts is a material statement about the chosen toolset.