| Your first sentence is very close to something I've said to others. NixOS is the first time I've been excited about an OS since first discovering Linux back in 2003. The OP mentions "the ability to do controlled per-user changes in an ad-hoc fashion". I assume they are referring to the use of "nix-env", which some members of the community frown upon. I've adopted the policy of not using it. My system is defined entirely by various ".nix" files, and for launching simple applications, such as firefox, I just have my xmonad configuration bind "C-SHIFT-F" to "nix-shell -p firefox --run firefox". For programs where I have more complicated environments, I have a "shell.nix" file in $HOME which contains a bunch of derivations that I commonly use, and I use "nix-shell -A" to enter them. For development, all of my projects now include a "default.nix" file. Typing "nix-shell" in the project directory then brings in my project's dependencies as well as the tools I want when developing on that project, such as a suitable Emacs with the appropriate packages already installed. I find I move these move ".nix" files frequently between different machines, and I really appreciate that I am put into reproducible development environments wherever they are. To reiterate what others have said below: the Nix package manager makes sure to share build inputs. If I start a new project and include a bunch of stuff in my "default.nix" that I use elsewhere, it costs nothing to enter the new environment. |