From cd049bfdf64d29a2b4859b8e146bb9b448d657ff Mon Sep 17 00:00:00 2001
From: Daiderd Jordan <daiderd@gmail.com>
Date: Thu, 29 Mar 2018 21:00:49 +0200
Subject: [PATCH] nix: use pkgs.nix by default instead of the default profile

This fixes version detection for 2.0.
---
 modules/nix/default.nix    | 11 +++++++++--
 modules/system/version.nix |  2 +-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/modules/nix/default.nix b/modules/nix/default.nix
index 09975096..540f84df 100644
--- a/modules/nix/default.nix
+++ b/modules/nix/default.nix
@@ -53,10 +53,14 @@ in
   options = {
     nix.package = mkOption {
       type = types.either types.package types.path;
-      default = "/nix/var/nix/profiles/default";
-      example = "pkgs.nix";
+      default = pkgs.nix;
+      defaultText = "pkgs.nix";
+      example = "pkgs.nixUnstable";
       description = ''
         This option specifies the package or profile that contains the version of Nix to use throughout the system.
+        To keep the version of nix originally installed the default profile can be used.
+
+        eg. /nix/var/nix/profiles/default
       '';
     };
 
@@ -331,6 +335,9 @@ in
         "/nix/var/nix/profiles/per-user/root/channels"
       ]);
 
+    nix.package = mkIf (config.system.stateVersion < 3)
+      "/nix/var/nix/profiles/default";
+
     environment.systemPackages = mkIf (isDerivation cfg.package)
       [ cfg.package ];
 
diff --git a/modules/system/version.nix b/modules/system/version.nix
index 72aeea77..5dda0db4 100644
--- a/modules/system/version.nix
+++ b/modules/system/version.nix
@@ -18,7 +18,7 @@ in
   options = {
     system.stateVersion = mkOption {
       type = types.int;
-      default = 2;
+      default = 3;
       description = ''
         Every once in a while, a new NixOS release may change
         configuration defaults in a way incompatible with stateful