configuration.nix

let
  nixpkgsRemote = remote: rev: import (builtins.fetchTarball "https://github.com/${remote}/Nixpkgs/archive/${rev}.tar.gz") {
    config = config.nixpkgs.config;
  };

  remotes = lib.mapAttrs (_: nixpkgsRemote) {
    upstream = "nixos";
    devel = "synthetica9";
  };

  master = builtins.trace
    "Warning: master is impure. Using this might have unexpected consequences!"
    (remotes.upstream "master");
  haskell-fix = remotes.upstream "69fa2d6bfba";
  qt510 = remotes.upstream "4b649a99d84";
  steamFix = remotes.devel "steam-update";
in
  # the rest of my config