diff --git a/.codeName b/.codeName
deleted file mode 100644
index 0bb82a2888e3..000000000000
--- a/.codeName
+++ /dev/null
@@ -1 +0,0 @@
-Koi
diff --git a/lib/trivial.nix b/lib/trivial.nix
index 811c298d8620..938df6ced476 100644
--- a/lib/trivial.nix
+++ b/lib/trivial.nix
@@ -98,9 +98,6 @@ rec {
   # The current nixpkgs version number as string.
   release = lib.strings.fileContents ../.version;
 
-  # Note: the first letter is bumped on every release.  It's an animal.
-  codeName = lib.strings.fileContents ../.codeName;
-
   # The current nixpkgs version suffix as string.
   versionSuffix =
     let suffixFile = ../.version-suffix;
diff --git a/pkgs/tools/nixos/nixos-rebuild/nix-fallback-paths.nix b/nixos/modules/installer/tools/nix-fallback-paths.nix
similarity index 100%
rename from pkgs/tools/nixos/nixos-rebuild/nix-fallback-paths.nix
rename to nixos/modules/installer/tools/nix-fallback-paths.nix
diff --git a/pkgs/tools/nixos/nixos-build-vms/nixos-build-vms.sh b/nixos/modules/installer/tools/nixos-build-vms/nixos-build-vms.sh
similarity index 99%
rename from pkgs/tools/nixos/nixos-build-vms/nixos-build-vms.sh
rename to nixos/modules/installer/tools/nixos-build-vms/nixos-build-vms.sh
index 237a807609a0..4e981c074a57 100644
--- a/pkgs/tools/nixos/nixos-build-vms/nixos-build-vms.sh
+++ b/nixos/modules/installer/tools/nixos-build-vms/nixos-build-vms.sh
@@ -35,7 +35,7 @@ do
 	    exit 0
 	    ;;
     esac
-
+    
     shift
 done
 
diff --git a/pkgs/tools/nixos/nixos-enter/nixos-enter.sh b/nixos/modules/installer/tools/nixos-enter.sh
similarity index 100%
rename from pkgs/tools/nixos/nixos-enter/nixos-enter.sh
rename to nixos/modules/installer/tools/nixos-enter.sh
diff --git a/pkgs/tools/nixos/nixos-generate-config/nixos-generate-config.pl b/nixos/modules/installer/tools/nixos-generate-config.pl
similarity index 100%
rename from pkgs/tools/nixos/nixos-generate-config/nixos-generate-config.pl
rename to nixos/modules/installer/tools/nixos-generate-config.pl
diff --git a/pkgs/tools/nixos/nixos-install/nixos-install.sh b/nixos/modules/installer/tools/nixos-install.sh
similarity index 100%
rename from pkgs/tools/nixos/nixos-install/nixos-install.sh
rename to nixos/modules/installer/tools/nixos-install.sh
diff --git a/pkgs/tools/nixos/nixos-option/nixos-option.sh b/nixos/modules/installer/tools/nixos-option.sh
similarity index 100%
rename from pkgs/tools/nixos/nixos-option/nixos-option.sh
rename to nixos/modules/installer/tools/nixos-option.sh
diff --git a/pkgs/tools/nixos/nixos-rebuild/nixos-rebuild.sh b/nixos/modules/installer/tools/nixos-rebuild.sh
similarity index 100%
rename from pkgs/tools/nixos/nixos-rebuild/nixos-rebuild.sh
rename to nixos/modules/installer/tools/nixos-rebuild.sh
diff --git a/pkgs/tools/nixos/nixos-version/nixos-version.sh b/nixos/modules/installer/tools/nixos-version.sh
similarity index 100%
rename from pkgs/tools/nixos/nixos-version/nixos-version.sh
rename to nixos/modules/installer/tools/nixos-version.sh
diff --git a/nixos/modules/installer/tools/tools.nix b/nixos/modules/installer/tools/tools.nix
index 6d9ebf750825..af0a3a2fcc88 100644
--- a/nixos/modules/installer/tools/tools.nix
+++ b/nixos/modules/installer/tools/tools.nix
@@ -6,35 +6,77 @@
 with lib;
 
 let
-  nixos-build-vms = pkgs.nixos-build-vms;
-  nixos-enter = pkgs.nixos-enter;
-  nixos-generate-config = pkgs.nixos-generate-config.override { inherit (config.system.nixos) release; };
-  nixos-install = pkgs.nixos-install.override { nix = config.nix.package; };
-  nixos-option = pkgs.nixos-option;
-  nixos-rebuild = pkgs.nixos-rebuild.override { nix = config.nix.package; };
-  nixos-version = pkgs.nixos-version.override { inherit (config.system.nixos) version codeName revision; };
+  makeProg = args: pkgs.substituteAll (args // {
+    dir = "bin";
+    isExecutable = true;
+  });
+
+  nixos-build-vms = makeProg {
+    name = "nixos-build-vms";
+    src = ./nixos-build-vms/nixos-build-vms.sh;
+  };
+
+  nixos-install = makeProg {
+    name = "nixos-install";
+    src = ./nixos-install.sh;
+    nix = config.nix.package.out;
+    path = makeBinPath [ nixos-enter ];
+  };
+
+  nixos-rebuild =
+    let fallback = import ./nix-fallback-paths.nix; in
+    makeProg {
+      name = "nixos-rebuild";
+      src = ./nixos-rebuild.sh;
+      nix = config.nix.package.out;
+      nix_x86_64_linux = fallback.x86_64-linux;
+      nix_i686_linux = fallback.i686-linux;
+    };
+
+  nixos-generate-config = makeProg {
+    name = "nixos-generate-config";
+    src = ./nixos-generate-config.pl;
+    path = [ pkgs.btrfs-progs ];
+    perl = "${pkgs.perl}/bin/perl -I${pkgs.perlPackages.FileSlurp}/lib/perl5/site_perl";
+    inherit (config.system.nixos) release;
+  };
+
+  nixos-option = makeProg {
+    name = "nixos-option";
+    src = ./nixos-option.sh;
+  };
+
+  nixos-version = makeProg {
+    name = "nixos-version";
+    src = ./nixos-version.sh;
+    inherit (config.system.nixos) version codeName revision;
+  };
+
+  nixos-enter = makeProg {
+    name = "nixos-enter";
+    src = ./nixos-enter.sh;
+  };
+
 in
 
 {
+
   config = {
-    environment.systemPackages = [
-      nixos-build-vms
-      nixos-enter
-      nixos-generate-config
-      nixos-install
-      nixos-option
-      nixos-rebuild
-      nixos-version
-    ];
+
+    environment.systemPackages =
+      [ nixos-build-vms
+        nixos-install
+        nixos-rebuild
+        nixos-generate-config
+        nixos-option
+        nixos-version
+        nixos-enter
+      ];
 
     system.build = {
-      inherit
-        nixos-enter
-        nixos-generate-config
-        nixos-install
-        nixos-option
-        nixos-rebuild
-        ;
+      inherit nixos-install nixos-generate-config nixos-option nixos-rebuild nixos-enter;
     };
+
   };
+
 }
diff --git a/nixos/modules/misc/version.nix b/nixos/modules/misc/version.nix
index fd77f6372720..6d78b7c593f8 100644
--- a/nixos/modules/misc/version.nix
+++ b/nixos/modules/misc/version.nix
@@ -43,7 +43,6 @@ in
     nixos.codeName = mkOption {
       readOnly = true;
       type = types.str;
-      default = lib.trivial.codeName;
       description = "The NixOS release code name (e.g. <literal>Emu</literal>).";
     };
 
@@ -80,6 +79,9 @@ in
       version = mkDefault (cfg.release + cfg.versionSuffix);
       revision      = mkIf (pathIsDirectory gitRepo) (mkDefault            gitCommitId);
       versionSuffix = mkIf (pathIsDirectory gitRepo) (mkDefault (".git." + gitCommitId));
+
+      # Note: the first letter is bumped on every release.  It's an animal.
+      codeName = "Koi";
     };
 
     # Generate /etc/os-release.  See
diff --git a/pkgs/tools/nixos/nixos-build-vms/default.nix b/pkgs/tools/nixos/nixos-build-vms/default.nix
deleted file mode 100644
index 579f80c8256c..000000000000
--- a/pkgs/tools/nixos/nixos-build-vms/default.nix
+++ /dev/null
@@ -1,7 +0,0 @@
-{ substituteAll }:
-substituteAll {
-  name = "nixos-build-vms";
-  dir = "bin";
-  isExecutable = true;
-  src = ./nixos-build-vms.sh;
-}
diff --git a/pkgs/tools/nixos/nixos-enter/default.nix b/pkgs/tools/nixos/nixos-enter/default.nix
deleted file mode 100644
index ccf455c40dcf..000000000000
--- a/pkgs/tools/nixos/nixos-enter/default.nix
+++ /dev/null
@@ -1,7 +0,0 @@
-{ substituteAll }:
-substituteAll {
-  name = "nixos-enter";
-  dir = "bin";
-  isExecutable = true;
-  src = ./nixos-enter.sh;
-}
diff --git a/pkgs/tools/nixos/nixos-generate-config/default.nix b/pkgs/tools/nixos/nixos-generate-config/default.nix
deleted file mode 100644
index 3d9e26d1d08d..000000000000
--- a/pkgs/tools/nixos/nixos-generate-config/default.nix
+++ /dev/null
@@ -1,16 +0,0 @@
-{ substituteAll
-, btrfs-progs
-, perl
-, perlPackages
-, lib
-, release ? lib.trivial.release
-}:
-substituteAll {
-  name = "nixos-generate-config";
-  dir = "bin";
-  isExecutable = true;
-  src = ./nixos-generate-config.pl;
-  path = [ btrfs-progs ];
-  perl = "${perl}/bin/perl -I${perlPackages.FileSlurp}/lib/perl5/site_perl";
-  inherit release;
-}
diff --git a/pkgs/tools/nixos/nixos-install/default.nix b/pkgs/tools/nixos/nixos-install/default.nix
deleted file mode 100644
index c652fb67f62f..000000000000
--- a/pkgs/tools/nixos/nixos-install/default.nix
+++ /dev/null
@@ -1,13 +0,0 @@
-{ substituteAll
-, lib
-, nix
-, nixos-enter
-}:
-substituteAll {
-  name = "nixos-install";
-  dir = "bin";
-  isExecutable = true;
-  src = ./nixos-install.sh;
-  nix = nix.out;
-  path = lib.makeBinPath [ nixos-enter ];
-}
diff --git a/pkgs/tools/nixos/nixos-option/default.nix b/pkgs/tools/nixos/nixos-option/default.nix
deleted file mode 100644
index 1fe84c01bced..000000000000
--- a/pkgs/tools/nixos/nixos-option/default.nix
+++ /dev/null
@@ -1,7 +0,0 @@
-{ substituteAll }:
-substituteAll {
-  name = "nixos-option";
-  dir = "bin";
-  isExecutable = true;
-  src = ./nixos-option.sh;
-}
diff --git a/pkgs/tools/nixos/nixos-rebuild/default.nix b/pkgs/tools/nixos/nixos-rebuild/default.nix
deleted file mode 100644
index 2216252f6cbf..000000000000
--- a/pkgs/tools/nixos/nixos-rebuild/default.nix
+++ /dev/null
@@ -1,13 +0,0 @@
-{ substituteAll, nix }:
-let
-  fallback = import ./nix-fallback-paths.nix;
-in
-  substituteAll {
-    name = "nixos-rebuild";
-    dir = "bin";
-    isExecutable = true;
-    src = ./nixos-rebuild.sh;
-    nix = nix.out;
-    nix_x86_64_linux = fallback.x86_64-linux;
-    nix_i686_linux = fallback.i686-linux;
-  }
diff --git a/pkgs/tools/nixos/nixos-version/default.nix b/pkgs/tools/nixos/nixos-version/default.nix
deleted file mode 100644
index f81f9ac9927b..000000000000
--- a/pkgs/tools/nixos/nixos-version/default.nix
+++ /dev/null
@@ -1,13 +0,0 @@
-{ substituteAll
-, lib
-, version ? lib.trivial.version
-, codeName ? "unknown"
-, revision ? lib.trivial.revisionWithDefault "master"
-}:
-substituteAll {
-  name = "nixos-version";
-  dir = "bin";
-  isExecutable = true;
-  src = ./nixos-version.sh;
-  inherit version codeName revision;
-}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 11719f6cd6f5..b0ac63a3e975 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -21955,16 +21955,6 @@ with pkgs;
     nixStable
     nixUnstable;
 
-  # NixOS tools
-  nixos-build-vms = callPackage ../tools/nixos/nixos-build-vms { };
-  nixos-enter = callPackage ../tools/nixos/nixos-enter { };
-  nixos-generate-config = callPackage ../tools/nixos/nixos-generate-config { };
-  nixos-install = callPackage ../tools/nixos/nixos-install { };
-  nixos-option = callPackage ../tools/nixos/nixos-option { };
-  nixos-rebuild = callPackage ../tools/nixos/nixos-rebuild { };
-  nixos-version = callPackage ../tools/nixos/nixos-version { };
-
-
   nixops = callPackage ../tools/package-management/nixops { };
 
   nixopsUnstable = lowPrio (callPackage ../tools/package-management/nixops/unstable.nix { });