Linux Ubuntu 18.04 - nix nixpkgs virtualbox - channel

my status quo Linux cc 4.15.0-22-generic #24-Ubuntu SMP Wed May 16 12:15:17 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux nix-env (Nix) 2.0.2 "18.09pre140705.090b7cc8f1b" I would like to use nixpkgs / nix package manager as my main system package manager. Is there method to install virtualbox? neither nix-prefetch-url http://download.virtualbox.org/virtualbox/5.2.12/Oracle_VM_VirtualBox_Extension_Pack-5.2.12-122591.vbox-extpack nix-env -i virtualbox nor nix-env -iA nixpkgs.linuxPackages.virtualboxGuestAdditions \ nixpkgs.linuxPackages.virtualbox worked. Another question is if there is a repository/channel with only binaries/pkgs that are valid and working for my use case [nix on Ubuntu and not NixOS]. - if not, is there a way to broke all packages in channels that are only for NixOS If e.g. conda and services like docker (and virtualbox?) [which have heavy dependencies (/issues)] don´t work on not NixOS systems, is there a use case as pkg-manager for nix (apart from nix-shell and nix for building])?