nix: set NIX_PATH per device versions at buildtime

Previously all devices would have NIX_PATH set on the common verion file
defindd in *nix/variables/versions.nix*. Now NIX_PATH is populated with
the versions of the respective device.

nix/default.nix

@@ -1,7 +1,5 @@
 { versionsPath }:
 
-{
-  channelSources =
 let
   channelVersions = (import versionsPath);
   mkChannelSource = channel:
@@ -17,7 +15,7 @@
       ref = (builtins.getAttr channel channelVersions)."ref";
       rev = (builtins.getAttr channel channelVersions)."rev";
   };
-      nix_path = builtins.foldl' (sum: elem: sum +":" + builtins.concatStringsSep "=" elem) "" [
+  nixPath = builtins.foldl' (sum: elem: sum +":" + builtins.concatStringsSep "=" elem) "" [
     [ "nixpkgs" (mkChannelSource "channelsNixosStable") ]
     [ "nixos" (mkChannelSource "channelsNixosStable" + "/nixos") ]
     [ "channels-nixos-stable" (mkChannelSource "channelsNixosStable") ]
@@ -25,7 +23,12 @@
     [ "nixpkgs-master" (mkChannelSource "nixpkgsMaster") ]
     [ "home-manager-module" (mkChannelSource "homeManagerModule") ]
   ];
-    in (import (mkChannelSource "channelsNixosStable") {}).writeText "channels.rc" ''
+  pkgs = import (mkChannelSource "channelsNixosStable") {};
-      export NIX_PATH=${nix_path}
+in
+
+{
+  inherit nixPath;
+  channelSources = pkgs.writeText "channels.rc" ''
+    export NIX_PATH=${nixPath}
   '';
 }

nix/home-manager/configuration/graphical-fullblown.nix

@@ -1,3 +1,9 @@
+{ pkgs }:
+
+let
+  zshCurried = import ../programs/zsh.nix { inherit pkgs; };
+in
+
 { pkgs
 , config
 , ... }:
@@ -20,7 +26,7 @@ in {
     ../programs/libreoffice.nix
     ../programs/neovim.nix
     ../programs/pass.nix
-    ../programs/zsh.nix
+    zshCurried
   ];
 
   nixpkgs.config = {

nix/home-manager/configuration/graphical-removable.nix

@@ -1,3 +1,9 @@
+{ pkgs }:
+
+let
+  zshCurried = import ../programs/zsh.nix { inherit pkgs; };
+in
+
 { pkgs
 , config,
 ... }:
@@ -17,7 +23,7 @@ in {
     ../programs/libreoffice.nix
     ../programs/neovim.nix
     ../programs/pass.nix
-    ../programs/zsh.nix
+    zshCurried
   ];
 
   nixpkgs.config = {

nix/home-manager/configuration/text-minimal.nix

@@ -1,3 +1,9 @@
+{ pkgs }:
+
+let
+  zshCurried = import ../programs/zsh.nix { inherit pkgs; };
+in
+
 { pkgs
 , config
 , ... }:
@@ -9,7 +15,7 @@ in {
     ../profiles/common.nix
     ../profiles/nix-channels.nix
     ../programs/neovim.nix
-    ../programs/zsh.nix
+    zshCurried
   ];
 
   nixpkgs.config = {

nix/home-manager/programs/zsh.nix

@@ -1,13 +1,8 @@
-{ pkgs
+{ pkgs }:
-, config
+
-, ...
+{ ... }:
-}:
 
 let
-  channelSources = (import ../../default.nix {
-      versionsPath = ../../variables/versions.nix;
-    }).channelSources;
-
   just-plugin =
     let
       plugin_file = pkgs.writeText "_just" ''
@@ -71,7 +66,7 @@ in {
       # don't cd into directories when executed
       unsetopt AUTO_CD
 
-      source ${channelSources}
+      export NIX_PATH="${pkgs.nixPath}"
 
       # print lines without termination
       setopt PROMPT_CR

nix/os/devices/steveej-t480s-work/pkg.nix

@@ -1,9 +1,12 @@
-{
+{ pkgs
-...
+, ...
 }:
 
 {
-  home-manager.users.steveej = import ../../../home-manager/configuration/graphical-fullblown.nix;
+  nixpkgs.config.packageOverrides = pkgs: with pkgs; {
+    nixPath = (import ../../../default.nix { versionsPath = ./versions.nix; }).nixPath;
+  };
+  home-manager.users.steveej = import ../../../home-manager/configuration/graphical-fullblown.nix { inherit pkgs; };
   services.teamviewer.enable = true;
   system.stateVersion = "19.09";
 }

nix/os/devices/vmd32387.contaboserver.net/pkg.nix

@@ -5,7 +5,10 @@
 }:
 
 {
-  home-manager.users.steveej = import ../../../home-manager/configuration/text-minimal.nix;
+  nixpkgs.config.packageOverrides = pkgs: with pkgs; {
+    nixPath = (import ../../../default.nix { versionsPath = ./versions.nix; }).nixPath;
+  };
+  home-manager.users.steveej = import ../../../home-manager/configuration/text-minimal.nix { inherit pkgs; };
 
  services.hydra = {
     enable = false;

nix/os/profiles/common/pkg.nix

@@ -6,7 +6,7 @@
   imports = [
     "${<home-manager-module>}/nixos"
   ];
-  home-manager.users.root = import ../../../home-manager/configuration/text-minimal.nix;
+  home-manager.users.root = import ../../../home-manager/configuration/text-minimal.nix { inherit pkgs; };
 
   nixpkgs.config = {
     allowBroken = false;

nix/os/profiles/common/system.nix

@@ -29,6 +29,10 @@
     }
   '';
 
+  environment.variables = {
+    NIX_PATH = lib.mkForce pkgs.nixPath;
+  };
+
   # Fonts, I18N, Date ...
   fonts.fonts = [
     pkgs.corefonts

nix/os/profiles/removable-medium/pkg.nix

@@ -1,7 +1,10 @@
-{
+{ pkgs
-...
+, ...
 }:
 
 {
-  home-manager.users.steveej = import ../../../home-manager/configuration/graphical-removable.nix;
+  nixpkgs.config.packageOverrides = pkgs: with pkgs; {
+    nixPath = (import ../../../default.nix { versionsPath = ./versions.nix; }).nixPath;
+  };
+  home-manager.users.steveej = import ../../../home-manager/configuration/graphical-removable.nix { inherit pkgs; };
 }