Nicer nix-gc call and vim as default EDITOR

configuration.nix

@@ -19,6 +19,7 @@
   };
 
   environment = {
+    variables.EDITOR = pkgs.lib.mkOverride 900 "vim"; # vim is my default editor
     shells = [ pkgs.zsh ];
     systemPackages = with pkgs; [
       wget emacs
@@ -219,6 +220,7 @@
 
   # Rasvaton / Fet-fri
   nix.gc.automatic = true;
+  nix.gc.options = "--delete-older-than 1w";
   nix.gc.dates = "02:22";
 
   # Upgrade when possible