One thing that differentiates nix from things like virtualenv is that each (package + version) tuple exists at most once in your local nix store and is then linked into your project environments, while virtualenv will install new copies of the packages. On the other hand you have to run the nix garbage collector to get rid of unused packages.
As for Windows support: It seems to be possible to use nix in WSL [0] but I've never tried that. I have used nix alongside apt and pacman on Ubuntu/Arch before I decided to go all the way and install the NixOS distribution. Using it alongside other package managers worked really well.
As for Windows support: It seems to be possible to use nix in WSL [0] but I've never tried that. I have used nix alongside apt and pacman on Ubuntu/Arch before I decided to go all the way and install the NixOS distribution. Using it alongside other package managers worked really well.
[0]: https://nixos.org/download.html#nix-install-windows