use Brother printer driver derivation flake

flake.nix

@@ -13,9 +13,14 @@
       url = "github:nix-community/disko";
       inputs.nixpkgs.follows = "nixpkgs";
     };
+
+    cups-brother-hl3172cdw = {
+      url = "github:hfxbse/nixos-config?ref=derivation/cups-brother-hl3172cdw";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
-  outputs = { self, nixpkgs, nixvim, disko }@attrs:
+  outputs = { self, cups-brother-hl3172cdw, disko, nixpkgs, nixvim }@attrs:
   let
     defaultModules = [
       # Nixvim needs to be an top level import
@@ -26,14 +31,15 @@
       ./modules/localization.nix
       ./modules/text-processing.nix
       ./modules/workplace-compliance.nix
-      ./modules/hardware/printers.nix
+      ./modules/printing.nix
       ./modules/hardware/Wooting/wootility.nix
       ./modules/development.nix
     ];
   in
   {
     nixosConfigurations.home-pc = nixpkgs.lib.nixosSystem {
       specialArgs = with attrs; {
+        cups-brother-hl3172cdw = cups-brother-hl3172cdw.packages.x86_64-linux.default;
         host = {
           user.name = "fxbse";
           user.description = "Fabian Haas";
@@ -47,6 +53,7 @@
 
     nixosConfigurations.nt-laptop = nixpkgs.lib.nixosSystem {
       specialArgs = with attrs; {
+        cups-brother-hl3172cdw = cups-brother-hl3172cdw.packages.x86_64-linux.default;
         host = rec {
           user.name = "fhs";
           user.description = "Fabian Haas";

modules/desktop/desktop.nix

@@ -53,11 +53,14 @@ in
 
     services.libinput.enable = lib.mkDefault cfg.touchpad.enable;
 
+    services.printing.enable = true;
+
     # Enable automatic login for the user.
     services.displayManager.autoLogin.enable = cfg.login == "auto";
     services.displayManager.autoLogin.user = lib.mkDefault username;
 
     boot.supportedFilesystems = [ "ntfs"  ];
+    # Support mounting MTP devices
     services.gvfs.enable = lib.mkDefault true;
 
     nixpkgs.config.allowUnfree = true;

modules/printing.nix

@@ -0,0 +1,10 @@
+{ config, cups-brother-hl3172cdw, lib, pkgs, ... }:
+let
+  allowUnfree = config.nixpkgs.config.allowUnfree;
+in
+{
+    services.printing = {
+        logLevel = "debug";
+        drivers = lib.optional allowUnfree cups-brother-hl3172cdw;
+    };
+}