I saw someone mentioning nixFlakes on IRC and thought I would try it out even though I had otherwise limited interest.
So here I am trying to install packages from nixos-unstable but don’t know how.
$ nix run nixpkgs:ghc works fine since it appears in https://github.com/NixOS/flake-registry and
nix flake list.
$ nix run nixos-unstable:ghc won’t work. I thought of adding nixos-unstable but it doesn’t contain a flake.nix (I just read through nix-flakes.md · GitHub).
How can I use nixos-unstable then (if that’s already possible)