Wow, just noticed this absolutely randomly. Thank you very much, @bkchr!

I just wanted to print for myself and observed that it did not work :D I found your issue while searching for the error message :)

@jgeerds @ttuegel anyone could merge this?

Applied to master (8152db9).

Should it be backported? To 18.03 and 17.09?

I think it needs to be backported to 18.03. I'm unsure about 17.09, because I don't know when it stopped working.

Cherry-picked to release-18.03 (fbc2cb7).

@bjornfor @bkchr the 17.09 had the same situation. The deal is - while its possible to add the printer via CUPS inteface, its done via PPD, so basically the hplip is dead without this. I need yet to test if this actually fixes it or there are additional stuff missing.

Obviously "hp-doctor" will be broken by the very design of NixOS, however if hplip-gui starts and capable to add/detect consequences with printer/scanner/fax we are fine.

I also noted that:

1. printer will refuse to print any "custom paper", which is available through GIMP menu for example.
2. GIMP preview creates HUGE offset fields on some paper formats, however they are not printed
3. Qt-based applications, such as Okular refuse to accept some paper types - which is very similar to this: https://forum.kde.org/viewtopic.php?f=289&t=136325

@cx405 I could add my printer with this this patch.

@bkchr Could I ask you how did you import the patched hplip? I am on 18.03 and doing:

{ config, pkgs, ... }:
let master = import <nixos-master> {}; in
{
...
services.printing.drivers = with pkgs; [ master.hplip ];
...
}

with

# nix-channel --list
nixos https://nixos.org/channels/nixos-18.03
nixos-master https://nixos.org/channels/nixos-unstable

leads to 1Gb pull of duplicate libraries. Could I ask you about advice for this type of per-package upgrade? I have HP Officejet pro 8600 (n911a).

I'm following the master branch of nixpkgs as my channel. You will probably need to wait for unstable or unstable-small to contain the fix.