reewide: Purge all uses `stdenv.system` and top-level `system`

It is deprecated and will be removed after 18.09.

74 files changed, 175 insertions, 175 deletions

diff --git a/pkgs/applications/altcoins/mist.nix b/pkgs/applications/altcoins/mist.nix
index 5f89b0a0c173..194c004f9c7f 100644
--- a/pkgs/applications/altcoins/mist.nix
+++ b/pkgs/applications/altcoins/mist.nix
@@ -4,7 +4,7 @@ let
   version = "0.11.1";
   name = "mist";
 
-  throwSystem = throw "Unsupported system: ${stdenv.system}";
+  throwSystem = throw "Unsupported system: ${stdenv.hostPlatform.system}";
 
   meta = with stdenv.lib; {
     description = "Browse and use Ðapps on the Ethereum network";
@@ -37,7 +37,7 @@ let
         url = "https://github.com/ethereum/mist/releases/download/v${version}/Mist-linux64-${urlVersion}.zip";
         sha256 = "0yx4x72l8gk68yh9saki48zgqx8k92xnkm79dc651wdpd5c25cz3";
       };
-    }.${stdenv.system} or throwSystem;
+    }.${stdenv.hostPlatform.system} or throwSystem;
 
     buildInputs = [ unzip makeWrapper ];
 
diff --git a/pkgs/applications/audio/baudline/default.nix b/pkgs/applications/audio/baudline/default.nix
index deaa3f98e52e..6827d12b3217 100644
--- a/pkgs/applications/audio/baudline/default.nix
+++ b/pkgs/applications/audio/baudline/default.nix
@@ -11,18 +11,18 @@ stdenv.mkDerivation rec {
   version = "1.08";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "http://www.baudline.com/baudline_${version}_linux_x86_64.tar.gz";
         sha256 = "09fn0046i69in1jpizkzbaq5ggij0mpflcsparyskm3wh71mbzvr";
       }
-    else if stdenv.system == "i686-linux" then
+    else if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         url = "http://www.baudline.com/baudline_${version}_linux_i686.tar.gz";
         sha256 = "1waip5pmcf5ffcfvn8lf1rvsaq2ab66imrbfqs777scz7k8fhhjb";
       }
     else
-      throw "baudline isn't supported (yet?) on ${stdenv.system}";
+      throw "baudline isn't supported (yet?) on ${stdenv.hostPlatform.system}";
 
   buildInputs = [ makeWrapper ];
 
diff --git a/pkgs/applications/audio/google-musicmanager/default.nix b/pkgs/applications/audio/google-musicmanager/default.nix
index 4cd3010ec3d3..b4fe78dcbfcd 100644
--- a/pkgs/applications/audio/google-musicmanager/default.nix
+++ b/pkgs/applications/audio/google-musicmanager/default.nix
@@ -1,6 +1,6 @@
 { stdenv, fetchurl
 , flac, expat, libidn, qtbase, qtwebkit, libvorbis }:
-assert stdenv.system == "x86_64-linux";
+assert stdenv.hostPlatform.system == "x86_64-linux";
 
 stdenv.mkDerivation rec {
   version = "beta_1.0.467.4929-r0"; # friendly to nix-env version sorting algo
diff --git a/pkgs/applications/audio/renoise/default.nix b/pkgs/applications/audio/renoise/default.nix
index 24a2f1a8a601..cd06fa80f5aa 100644
--- a/pkgs/applications/audio/renoise/default.nix
+++ b/pkgs/applications/audio/renoise/default.nix
@@ -17,7 +17,7 @@ stdenv.mkDerivation rec {
   version = "3.1.0";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
         if builtins.isNull releasePath then
         fetchurl {
           url = "https://files.renoise.com/demo/Renoise_${urlVersion version}_Demo_x86_64.tar.bz2";
@@ -25,7 +25,7 @@ stdenv.mkDerivation rec {
         }
         else
         releasePath
-    else if stdenv.system == "i686-linux" then
+    else if stdenv.hostPlatform.system == "i686-linux" then
         if builtins.isNull releasePath then
         fetchurl {
           url = "http://files.renoise.com/demo/Renoise_${urlVersion version}_Demo_x86.tar.bz2";
diff --git a/pkgs/applications/audio/transcribe/default.nix b/pkgs/applications/audio/transcribe/default.nix
index 5ec5087b9f26..c6d5ebc1627f 100644
--- a/pkgs/applications/audio/transcribe/default.nix
+++ b/pkgs/applications/audio/transcribe/default.nix
@@ -7,12 +7,12 @@ stdenv.mkDerivation rec {
   name = "transcribe-${version}";
   version = "8.40";
 
-  src = if stdenv.system == "i686-linux" then
+  src = if stdenv.hostPlatform.system == "i686-linux" then
     fetchzip {
       url = "https://www.seventhstring.com/xscribe/downlinux32_old/xscsetup.tar.gz";
       sha256 = "1ngidmj9zz8bmv754s5xfsjv7v6xr03vck4kigzq4bpc9b1fdhjq";
     }
-  else if stdenv.system == "x86_64-linux" then
+  else if stdenv.hostPlatform.system == "x86_64-linux" then
     fetchzip {
       url = "https://www.seventhstring.com/xscribe/downlinux64_old/xsc64setup.tar.gz";
       sha256 = "0svzi8svj6zn06gj0hr8mpnhq4416dvb4g5al0gpb1g3paywdaf9";
diff --git a/pkgs/applications/editors/eclipse/build-eclipse.nix b/pkgs/applications/editors/eclipse/build-eclipse.nix
index a26d380ec1df..389608ad8249 100644
--- a/pkgs/applications/editors/eclipse/build-eclipse.nix
+++ b/pkgs/applications/editors/eclipse/build-eclipse.nix
@@ -2,7 +2,7 @@
 , zlib, jdk, glib, gtk3, libXtst, gsettings-desktop-schemas, webkitgtk
 , makeWrapper, ... }:
 
-{ name, src ? builtins.getAttr stdenv.system sources, sources ? null, description }:
+{ name, src ? builtins.getAttr stdenv.hostPlatform.system sources, sources ? null, description }:
 
 stdenv.mkDerivation rec {
   inherit name src;
diff --git a/pkgs/applications/editors/eclipse/default.nix b/pkgs/applications/editors/eclipse/default.nix
index c719c7b2da1a..8d47a551c93e 100644
--- a/pkgs/applications/editors/eclipse/default.nix
+++ b/pkgs/applications/editors/eclipse/default.nix
@@ -27,24 +27,24 @@ rec {
     name = "eclipse-cpp-4.7.0";
     description = "Eclipse IDE for C/C++ Developers, Oxygen release";
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = https://www.eclipse.org/downloads/download.php?r=1&nf=1&file=/technology/epp/downloads/release/oxygen/R/eclipse-cpp-oxygen-R-linux-gtk-x86_64.tar.gz;
           sha512 = "813c791e739d7d0e2ab242a5bacadca135bbeee20ef97aa830353cd90f63fa6e9c89cfcc6aadf635c742befe035bd6e3f15103013f63c419f6144e86ebde3ed1";
         }
-      else if stdenv.system == "i686-linux" then
+      else if stdenv.hostPlatform.system == "i686-linux" then
         fetchurl {
           url = https://www.eclipse.org/downloads/download.php?r=1&nf=1&file=/technology/epp/downloads/release/oxygen/R/eclipse-cpp-oxygen-R-linux-gtk.tar.gz;
           sha512 = "2b50f4a00306a89cda1aaaa606e62285cacbf93464a9dd3f3319dca3e2c578b802e685de6f78e5e617d269e21271188effe73d41f491a6de946e28795d82db8a";
         }
-      else throw "Unsupported system: ${stdenv.system}";
+      else throw "Unsupported system: ${stdenv.hostPlatform.system}";
   };
 
   eclipse-cpp-37 = buildEclipse {
     name = "eclipse-cpp-3.7";
     description = "Eclipse IDE for C/C++ Developers";
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = https://www.eclipse.org/downloads/download.php?r=1&nf=1&file=/technology/epp/downloads/release/indigo/R/eclipse-cpp-indigo-incubation-linux-gtk-x86_64.tar.gz;
           sha256 = "14ppc9g9igzvj1pq7jl01vwhzb66nmzbl9wsdl1sf3xnwa9wnqk3";
@@ -65,7 +65,7 @@ rec {
     name = "eclipse-modeling-4.7";
     description = "Eclipse Modeling Tools";
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = https://www.eclipse.org/downloads/download.php?r=1&nf=1&file=/technology/epp/downloads/release/oxygen/R/eclipse-modeling-oxygen-R-linux-gtk-x86_64.tar.gz;
           sha512 = "3b9a7ad4b5d6b77fbdd64e8d323e0adb6c2904763ad042b374b4d87cef8607408cb407e395870fc755d58c0c800e20818adcf456ebe193d76cede16c5fe12271";
@@ -81,7 +81,7 @@ rec {
     name = "eclipse-modeling-3.6.2";
     description = "Eclipse Modeling Tools (includes Incubating components)";
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = https://www.eclipse.org/downloads/download.php?r=1&nf=1&file=/technology/epp/downloads/release/helios/SR2/eclipse-modeling-helios-SR2-incubation-linux-gtk-x86_64.tar.gz;
           sha1 = "e96f5f006298f68476f4a15a2be8589158d5cc61";
@@ -151,7 +151,7 @@ rec {
     name = "eclipse-scala-sdk-4.4.1";
     description = "Eclipse IDE for Scala Developers";
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl { # tested
           url = https://downloads.typesafe.com/scalaide-pack/4.4.1-vfinal-luna-211-20160504/scala-SDK-4.4.1-vfinal-2.11-linux.gtk.x86_64.tar.gz;
           sha256  = "4c2d1ac68384e12a11a851cf0fc7757aea087eba69329b21d539382a65340d27";
diff --git a/pkgs/applications/editors/jetbrains/common.nix b/pkgs/applications/editors/jetbrains/common.nix
index 04de4f564c33..2bb84bce0b12 100644
--- a/pkgs/applications/editors/jetbrains/common.nix
+++ b/pkgs/applications/editors/jetbrains/common.nix
@@ -42,7 +42,7 @@ with stdenv; lib.makeOverridable mkDerivation rec {
       }
 
       interpreter=$(echo ${stdenv.glibc.out}/lib/ld-linux*.so.2)
-      if [ "${stdenv.system}" == "x86_64-linux" ]; then
+      if [ "${stdenv.hostPlatform.system}" == "x86_64-linux" ]; then
         target_size=$(get_file_size bin/fsnotifier64)
         patchelf --set-interpreter "$interpreter" bin/fsnotifier64
         munge_size_hack bin/fsnotifier64 $target_size
diff --git a/pkgs/applications/editors/kodestudio/default.nix b/pkgs/applications/editors/kodestudio/default.nix
index 4e22e032e357..b212773712c2 100644
--- a/pkgs/applications/editors/kodestudio/default.nix
+++ b/pkgs/applications/editors/kodestudio/default.nix
@@ -8,15 +8,15 @@ let
 
   version = "17.1";
 
-  sha256 = if stdenv.system == "x86_64-linux"  then "1kddisnvlk48jip6k59mw3wlkrl7rkck2lxpaghn0gfx02cvms5f"
-      else if stdenv.system == "i686-cygwin"   then "1izp42afrlh4yd322ax9w85ki388gnkqfqbw8dwnn4k3j7r5487z"
-      else throw "Unsupported system: ${stdenv.system}";
+  sha256 = if stdenv.hostPlatform.system == "x86_64-linux"  then "1kddisnvlk48jip6k59mw3wlkrl7rkck2lxpaghn0gfx02cvms5f"
+      else if stdenv.hostPlatform.system == "i686-cygwin"   then "1izp42afrlh4yd322ax9w85ki388gnkqfqbw8dwnn4k3j7r5487z"
+      else throw "Unsupported system: ${stdenv.hostPlatform.system}";
 
   urlBase = "https://github.com/Kode/KodeStudio/releases/download/v${version}/KodeStudio-";
 
-  urlStr = if stdenv.system == "x86_64-linux"  then urlBase + "linux64.tar.gz"
-      else if stdenv.system == "i686-cygwin"   then urlBase + "win32.zip"
-      else throw "Unsupported system: ${stdenv.system}";
+  urlStr = if stdenv.hostPlatform.system == "x86_64-linux"  then urlBase + "linux64.tar.gz"
+      else if stdenv.hostPlatform.system == "i686-cygwin"   then urlBase + "win32.zip"
+      else throw "Unsupported system: ${stdenv.hostPlatform.system}";
 
 in
 
@@ -47,7 +47,7 @@ in
       cp -r ./* $out
     '';
 
-    postFixup = lib.optionalString (stdenv.system == "i686-linux" || stdenv.system == "x86_64-linux") ''
+    postFixup = lib.optionalString (stdenv.hostPlatform.system == "i686-linux" || stdenv.hostPlatform.system == "x86_64-linux") ''
       # Patch Binaries
       patchelf \
           --set-interpreter "$(cat $NIX_CC/nix-support/dynamic-linker)" \
diff --git a/pkgs/applications/editors/music/tuxguitar/default.nix b/pkgs/applications/editors/music/tuxguitar/default.nix
index f305db1abb8f..1b1c6eaf9e54 100644
--- a/pkgs/applications/editors/music/tuxguitar/default.nix
+++ b/pkgs/applications/editors/music/tuxguitar/default.nix
@@ -1,7 +1,7 @@
 { stdenv, fetchurl, swt, jdk, makeWrapper, alsaLib }:
 
-let metadata = assert stdenv.system == "i686-linux" || stdenv.system == "x86_64-linux";
-  if stdenv.system == "i686-linux" then
+let metadata = assert stdenv.hostPlatform.system == "i686-linux" || stdenv.hostPlatform.system == "x86_64-linux";
+  if stdenv.hostPlatform.system == "i686-linux" then
     { arch = "x86"; sha256 = "1qmb51k0538pn7gv4nsvhfv33xik4l4af0qmpllkzrikmj8wvzlb"; }
   else
     { arch = "x86_64"; sha256 = "12af47jhlrh9aq5b3d13l7cdhlndgnfpy61gz002hajbq7i00ixh"; };
diff --git a/pkgs/applications/editors/sublime/2/default.nix b/pkgs/applications/editors/sublime/2/default.nix
index 78c2d9aaa0c4..11724d9802a5 100644
--- a/pkgs/applications/editors/sublime/2/default.nix
+++ b/pkgs/applications/editors/sublime/2/default.nix
@@ -6,7 +6,7 @@ in
 stdenv.mkDerivation rec {
   name = "sublimetext-2.0.2";
   src =
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         name = "sublimetext-2.0.2.tar.bz2";
         url = http://c758482.r82.cf2.rackcdn.com/Sublime%20Text%202.0.2.tar.bz2;
diff --git a/pkgs/applications/editors/sublime/3/common.nix b/pkgs/applications/editors/sublime/3/common.nix
index 628993dbf5be..eb282b1be3a8 100644
--- a/pkgs/applications/editors/sublime/3/common.nix
+++ b/pkgs/applications/editors/sublime/3/common.nix
@@ -13,13 +13,13 @@ let
     ++ stdenv.lib.optional gksuSupport "/usr/bin/gksudo=${gksu}/bin/gksudo";
 in let
   archSha256 =
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       x32sha256
     else
       x64sha256;
 
   arch =
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       "x32"
     else
       "x64";
diff --git a/pkgs/applications/editors/typora/default.nix b/pkgs/applications/editors/typora/default.nix
index 93ee70e4148b..0bff4864c612 100644
--- a/pkgs/applications/editors/typora/default.nix
+++ b/pkgs/applications/editors/typora/default.nix
@@ -6,7 +6,7 @@ stdenv.mkDerivation rec {
   version = "0.9.53";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://www.typora.io/linux/typora_${version}_amd64.deb";
         sha256 = "02k6x30l4mbjragqbq5rn663xbw3h4bxzgppfxqf5lwydswldklb";
diff --git a/pkgs/applications/editors/vscode/default.nix b/pkgs/applications/editors/vscode/default.nix
index a775fb3bd79a..0cf0c7bcbc69 100644
--- a/pkgs/applications/editors/vscode/default.nix
+++ b/pkgs/applications/editors/vscode/default.nix
@@ -9,15 +9,15 @@ let
     "i686-linux" = "linux-ia32";
     "x86_64-linux" = "linux-x64";
     "x86_64-darwin" = "darwin";
-  }.${stdenv.system};
+  }.${stdenv.hostPlatform.system};
 
   sha256 = {
     "i686-linux" = "1g7kqbz6mrf8ngx2bnwpi9fifq5rjznxgsgwjb532z3nh92ypa8n";
     "x86_64-linux" = "02yldycakn5zxj1ji4nmhdyazqlkjqpzdj3g8j501c3j28pgiwjy";
     "x86_64-darwin" = "0pnsfkh20mj7pzqw7wlfd98jqc6a1mnsq1iira15n7fafqgj8zpl";
-  }.${stdenv.system};
+  }.${stdenv.hostPlatform.system};
 
-  archive_fmt = if stdenv.system == "x86_64-darwin" then "zip" else "tar.gz";
+  archive_fmt = if stdenv.hostPlatform.system == "x86_64-darwin" then "zip" else "tar.gz";
 
   rpath = lib.concatStringsSep ":" [
     atomEnv.libPath
@@ -48,12 +48,12 @@ in
       categories = "GNOME;GTK;Utility;TextEditor;Development;";
     };
 
-    buildInputs = if stdenv.system == "x86_64-darwin"
+    buildInputs = if stdenv.hostPlatform.system == "x86_64-darwin"
       then [ unzip libXScrnSaver libsecret ]
       else [ wrapGAppsHook libXScrnSaver libxkbfile libsecret ];
 
     installPhase =
-      if stdenv.system == "x86_64-darwin" then ''
+      if stdenv.hostPlatform.system == "x86_64-darwin" then ''
         mkdir -p $out/lib/vscode $out/bin
         cp -r ./* $out/lib/vscode
         ln -s $out/lib/vscode/Contents/Resources/app/bin/code $out/bin
@@ -72,7 +72,7 @@ in
         cp $out/lib/vscode/resources/app/resources/linux/code.png $out/share/pixmaps/code.png
       '';
 
-    postFixup = lib.optionalString (stdenv.system == "i686-linux" || stdenv.system == "x86_64-linux") ''
+    postFixup = lib.optionalString (stdenv.hostPlatform.system == "i686-linux" || stdenv.hostPlatform.system == "x86_64-linux") ''
       patchelf \
         --set-interpreter "$(cat $NIX_CC/nix-support/dynamic-linker)" \
         --set-rpath "${rpath}" \
diff --git a/pkgs/applications/graphics/ImageMagick/7.0.nix b/pkgs/applications/graphics/ImageMagick/7.0.nix
index c4afd6b3bed3..893f8d1da6d7 100644
--- a/pkgs/applications/graphics/ImageMagick/7.0.nix
+++ b/pkgs/applications/graphics/ImageMagick/7.0.nix
@@ -7,10 +7,10 @@
 
 let
   arch =
-    if stdenv.system == "i686-linux" then "i686"
-    else if stdenv.system == "x86_64-linux" || stdenv.system == "x86_64-darwin" then "x86-64"
-    else if stdenv.system == "armv7l-linux" then "armv7l"
-    else if stdenv.system == "aarch64-linux" then "aarch64"
+    if stdenv.hostPlatform.system == "i686-linux" then "i686"
+    else if stdenv.hostPlatform.system == "x86_64-linux" || stdenv.hostPlatform.system == "x86_64-darwin" then "x86-64"
+    else if stdenv.hostPlatform.system == "armv7l-linux" then "armv7l"
+    else if stdenv.hostPlatform.system == "aarch64-linux" then "aarch64"
     else throw "ImageMagick is not supported on this platform.";
 
   cfg = {
diff --git a/pkgs/applications/graphics/ImageMagick/default.nix b/pkgs/applications/graphics/ImageMagick/default.nix
index 94a4aeaa9337..22d1341f0dcf 100644
--- a/pkgs/applications/graphics/ImageMagick/default.nix
+++ b/pkgs/applications/graphics/ImageMagick/default.nix
@@ -7,10 +7,10 @@
 
 let
   arch =
-    if stdenv.system == "i686-linux" then "i686"
-    else if stdenv.system == "x86_64-linux" || stdenv.system == "x86_64-darwin" then "x86-64"
-    else if stdenv.system == "armv7l-linux" then "armv7l"
-    else if stdenv.system == "aarch64-linux" then "aarch64"
+    if stdenv.hostPlatform.system == "i686-linux" then "i686"
+    else if stdenv.hostPlatform.system == "x86_64-linux" || stdenv.hostPlatform.system == "x86_64-darwin" then "x86-64"
+    else if stdenv.hostPlatform.system == "armv7l-linux" then "armv7l"
+    else if stdenv.hostPlatform.system == "aarch64-linux" then "aarch64"
     else throw "ImageMagick is not supported on this platform.";
 
   cfg = {
diff --git a/pkgs/applications/graphics/gcolor2/default.nix b/pkgs/applications/graphics/gcolor2/default.nix
index 3747b802e231..27ca6e26e9f9 100644
--- a/pkgs/applications/graphics/gcolor2/default.nix
+++ b/pkgs/applications/graphics/gcolor2/default.nix
@@ -3,7 +3,7 @@
 let version = "0.4"; in
 stdenv.mkDerivation {
   name = "gcolor2-${version}";
-  arch = if stdenv.system == "x86_64-linux" then "amd64" else "386";
+  arch = if stdenv.hostPlatform.system == "x86_64-linux" then "amd64" else "386";
 
   src = fetchurl {
     url = "mirror://sourceforge/project/gcolor2/gcolor2/${version}/gcolor2-${version}.tar.bz2";
@@ -16,7 +16,7 @@ stdenv.mkDerivation {
   '';
 
   # from https://github.com/PhantomX/slackbuilds/tree/master/gcolor2/patches
-  patches = if stdenv.system == "x86_64-linux" then
+  patches = if stdenv.hostPlatform.system == "x86_64-linux" then
         [ ./gcolor2-amd64.patch ] else
         [ ];
 
diff --git a/pkgs/applications/graphics/sane/backends/brscan4/default.nix b/pkgs/applications/graphics/sane/backends/brscan4/default.nix
index df44c132ed96..b431cf51b019 100644
--- a/pkgs/applications/graphics/sane/backends/brscan4/default.nix
+++ b/pkgs/applications/graphics/sane/backends/brscan4/default.nix
@@ -12,17 +12,17 @@ let
 in stdenv.mkDerivation rec {
   name = "brscan4-0.4.4-4";
   src = 
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         url = "http://download.brother.com/welcome/dlf006646/${name}.i386.deb";
         sha256 = "13mhjbzf9nvpdzrc2s98684r7likg76zxs1wlz2h8w59fsqgx4k2";
       }
-    else if stdenv.system == "x86_64-linux" then
+    else if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://download.brother.com/welcome/dlf006645/${name}.amd64.deb";
         sha256 = "0xy5px96y1saq9l80vwvfn6anr2q42qlxdhm6ci2a0diwib5q9fd";
       }
-    else throw "${name} is not supported on ${stdenv.system} (only i686-linux and x86_64 linux are supported)";
+    else throw "${name} is not supported on ${stdenv.hostPlatform.system} (only i686-linux and x86_64 linux are supported)";
 
   unpackPhase = ''
     ar x $src
diff --git a/pkgs/applications/graphics/unigine-valley/default.nix b/pkgs/applications/graphics/unigine-valley/default.nix
index f1adc6bd10ea..d29c9cd82598 100644
--- a/pkgs/applications/graphics/unigine-valley/default.nix
+++ b/pkgs/applications/graphics/unigine-valley/default.nix
@@ -17,12 +17,12 @@
 let
   version = "1.0";
 
-  arch = if stdenv.system == "x86_64-linux" then
+  arch = if stdenv.hostPlatform.system == "x86_64-linux" then
     "x64"
-  else if stdenv.system == "i686-linux" then
+  else if stdenv.hostPlatform.system == "i686-linux" then
     "x86"
   else
-    throw "Unsupported platform ${stdenv.system}";
+    throw "Unsupported platform ${stdenv.hostPlatform.system}";
 
 in
   stdenv.mkDerivation rec {
diff --git a/pkgs/applications/misc/1password/default.nix b/pkgs/applications/misc/1password/default.nix
index 94dfc68fb59b..331f516c88ce 100644
--- a/pkgs/applications/misc/1password/default.nix
+++ b/pkgs/applications/misc/1password/default.nix
@@ -4,19 +4,19 @@ stdenv.mkDerivation rec {
   name = "1password-${version}";
   version = "0.5.3";
   src =
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       fetchzip {
         url = "https://cache.agilebits.com/dist/1P/op/pkg/v${version}/op_linux_386_v${version}.zip";
         sha256 = "05s223h1yps4k9kmignl0r5sbh6w7m1hnlmafnf1kiwv7gacvxjc";
         stripRoot = false;
       }
-    else if stdenv.system == "x86_64-linux" then
+    else if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchzip {
         url = "https://cache.agilebits.com/dist/1P/op/pkg/v${version}/op_linux_amd64_v${version}.zip";
         sha256 = "0p9x1fx0309v8dxxaf88m8x8q15zzqywfmjn6v5wb9v3scp9396v";
         stripRoot = false;
       }
-    else if stdenv.system == "x86_64-darwin" then
+    else if stdenv.hostPlatform.system == "x86_64-darwin" then
       fetchzip {
         url = "https://cache.agilebits.com/dist/1P/op/pkg/v${version}/op_darwin_amd64_v${version}.zip";
         sha256 = "1z2xp9bn93gr4ha6zx65va1fb58a2xlnnmpv583y96gq3vbnqdcj";
diff --git a/pkgs/applications/misc/adobe-reader/default.nix b/pkgs/applications/misc/adobe-reader/default.nix
index 88bf87b0a84f..0ca12a0096ed 100644
--- a/pkgs/applications/misc/adobe-reader/default.nix
+++ b/pkgs/applications/misc/adobe-reader/default.nix
@@ -1,7 +1,7 @@
 { stdenv, fetchurl, libX11, cups, zlib, libxml2, pango, atk, gtk2, glib
 , gdk_pixbuf }:
 
-assert stdenv.system == "i686-linux";
+assert stdenv.hostPlatform.system == "i686-linux";
 
 let version = "9.5.5"; in
 
diff --git a/pkgs/applications/misc/cura/lulzbot.nix b/pkgs/applications/misc/cura/lulzbot.nix
index 6a36e42eaa3d..f3f1972f6e6e 100644
--- a/pkgs/applications/misc/cura/lulzbot.nix
+++ b/pkgs/applications/misc/cura/lulzbot.nix
@@ -8,17 +8,17 @@ stdenv.mkDerivation rec {
   version = "15.02.1-1.03-5064";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://download.alephobjects.com/ao/aodeb/dists/jessie/main/binary-amd64/cura_${version}_amd64.deb";
         sha256 = "1gsfidg3gim5pjbl82vkh0cw4ya253m4p7nirm8nr6yjrsirkzxg";
       }
-    else if stdenv.system == "i686-linux" then
+    else if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         url = "http://download.alephobjects.com/ao/aodeb/dists/jessie/main/binary-i386/cura_${version}_i386.deb";
         sha256 = "0xd3df6bxq4rijgvsqvps454jkc1nzhxbdzzj6j2w317ppsbhyc1";
       }
-    else throw "${name} is not supported on ${stdenv.system}";
+    else throw "${name} is not supported on ${stdenv.hostPlatform.system}";
 
   python_deps = with py; [ pyopengl pyserial numpy wxPython30 power setuptools ];
   pythonPath = python_deps;
diff --git a/pkgs/applications/misc/googleearth/default.nix b/pkgs/applications/misc/googleearth/default.nix
index 9c1b457c299d..96f8cb116143 100644
--- a/pkgs/applications/misc/googleearth/default.nix
+++ b/pkgs/applications/misc/googleearth/default.nix
@@ -4,9 +4,9 @@
 
 let
   arch =
-    if stdenv.system == "x86_64-linux" then "amd64"
-    else if stdenv.system == "i686-linux" then "i386"
-    else throw "Unsupported system ${stdenv.system}";
+    if stdenv.hostPlatform.system == "x86_64-linux" then "amd64"
+    else if stdenv.hostPlatform.system == "i686-linux" then "i386"
+    else throw "Unsupported system ${stdenv.hostPlatform.system}";
   sha256 =
     if arch == "amd64"
     then "0dwnppn5snl5bwkdrgj4cyylnhngi0g66fn2k41j3dvis83x24k6"
diff --git a/pkgs/applications/misc/icesl/default.nix b/pkgs/applications/misc/icesl/default.nix
index 49b1741fd5af..c0c1faef09d2 100644
--- a/pkgs/applications/misc/icesl/default.nix
+++ b/pkgs/applications/misc/icesl/default.nix
@@ -6,10 +6,10 @@ stdenv.mkDerivation rec {
   name = "iceSL-${version}";
   version = "2.1.10";
 
-  src =  if stdenv.system == "x86_64-linux" then fetchzip {
+  src =  if stdenv.hostPlatform.system == "x86_64-linux" then fetchzip {
     url = "https://gforge.inria.fr/frs/download.php/file/37268/icesl${version}-amd64.zip";
     sha256 = "0dv3mq6wy46xk9blzzmgbdxpsjdaxid3zadfrysxlhmgl7zb2cn2";
-  } else if stdenv.system == "i686-linux" then fetchzip {
+  } else if stdenv.hostPlatform.system == "i686-linux" then fetchzip {
     url = "https://gforge.inria.fr/frs/download.php/file/37267/icesl${version}-i386.zip";
     sha256 = "0sl54fsb2gz6dy0bwdscpdq1ab6ph5b7zald3bwzgkqsvna7p1jr";
   } else throw "Unsupported architecture";
diff --git a/pkgs/applications/misc/kdbplus/default.nix b/pkgs/applications/misc/kdbplus/default.nix
index ba048761367c..b518481e29ad 100644
--- a/pkgs/applications/misc/kdbplus/default.nix
+++ b/pkgs/applications/misc/kdbplus/default.nix
@@ -1,6 +1,6 @@
 { stdenv, requireFile, unzip, rlwrap, bash }:
 
-assert (stdenv.system == "i686-linux");
+assert (stdenv.hostPlatform.system == "i686-linux");
 
 let
   libPath = stdenv.lib.makeLibraryPath
diff --git a/pkgs/applications/misc/kiwix/default.nix b/pkgs/applications/misc/kiwix/default.nix
index c37d26f3dbcc..8d095b78cdbf 100644
--- a/pkgs/applications/misc/kiwix/default.nix
+++ b/pkgs/applications/misc/kiwix/default.nix
@@ -25,7 +25,7 @@ let
     sha256 = "1h9vcbvf8wgds6i2z20y7krpys0mqsqhv1ijyfljanp6vyll9fvi";
   };
 
-  xulrunner = if stdenv.system == "x86_64-linux"
+  xulrunner = if stdenv.hostPlatform.system == "x86_64-linux"
               then { tar = xulrunner64_tar; sdk = xulrunnersdk64_tar; }
               else { tar = xulrunner32_tar; sdk = xulrunnersdk32_tar; };
 
diff --git a/pkgs/applications/misc/playonlinux/default.nix b/pkgs/applications/misc/playonlinux/default.nix
index 2ad6321d5191..8c9f13ce92c7 100644
--- a/pkgs/applications/misc/playonlinux/default.nix
+++ b/pkgs/applications/misc/playonlinux/default.nix
@@ -44,9 +44,9 @@ let
     ];
 
   ld32 =
-    if stdenv.system == "x86_64-linux" then "${stdenv.cc}/nix-support/dynamic-linker-m32"
-    else if stdenv.system == "i686-linux" then "${stdenv.cc}/nix-support/dynamic-linker"
-    else throw "Unsupported platform for PlayOnLinux: ${stdenv.system}";
+    if stdenv.hostPlatform.system == "x86_64-linux" then "${stdenv.cc}/nix-support/dynamic-linker-m32"
+    else if stdenv.hostPlatform.system == "i686-linux" then "${stdenv.cc}/nix-support/dynamic-linker"
+    else throw "Unsupported platform for PlayOnLinux: ${stdenv.hostPlatform.system}";
   ld64 = "${stdenv.cc}/nix-support/dynamic-linker";
   libs = pkgs: stdenv.lib.makeLibraryPath [ pkgs.xorg.libX11 ];
 
@@ -83,7 +83,7 @@ in stdenv.mkDerivation {
 
     bunzip2 $out/share/playonlinux/bin/check_dd_x86.bz2
     patchelf --set-interpreter $(cat ${ld32}) --set-rpath ${libs pkgsi686Linux} $out/share/playonlinux/bin/check_dd_x86
-    ${if stdenv.system == "x86_64-linux" then ''
+    ${if stdenv.hostPlatform.system == "x86_64-linux" then ''
       bunzip2 $out/share/playonlinux/bin/check_dd_amd64.bz2
       patchelf --set-interpreter $(cat ${ld64}) --set-rpath ${libs pkgs} $out/share/playonlinux/bin/check_dd_amd64
     '' else ''
diff --git a/pkgs/applications/misc/rescuetime/default.nix b/pkgs/applications/misc/rescuetime/default.nix
index 57cdfd08d5b0..d9cd85d5098a 100644
--- a/pkgs/applications/misc/rescuetime/default.nix
+++ b/pkgs/applications/misc/rescuetime/default.nix
@@ -2,7 +2,7 @@
 
 let
   src =
-    if stdenv.system == "i686-linux" then fetchurl {
+    if stdenv.hostPlatform.system == "i686-linux" then fetchurl {
       name = "rescuetime-installer.deb";
       url = "https://www.rescuetime.com/installers/rescuetime_current_i386.deb";
       sha256 = "06q1jwqsrjvlj820dd4vl80jznwafsqshsg0p6si8qx4721blryz";
diff --git a/pkgs/applications/misc/sweethome3d/default.nix b/pkgs/applications/misc/sweethome3d/default.nix
index 68a192d78b84..3c56a6a046fb 100644
--- a/pkgs/applications/misc/sweethome3d/default.nix
+++ b/pkgs/applications/misc/sweethome3d/default.nix
@@ -55,7 +55,7 @@ let
 
       makeWrapper ${jre}/bin/java $out/bin/$exec \
         --prefix XDG_DATA_DIRS : "$XDG_ICON_DIRS:${gtk3.out}/share:${gsettings-desktop-schemas}/share:$out/share:$GSETTINGS_SCHEMAS_PATH" \
-        --add-flags "-jar $out/share/java/${module}-${version}.jar -cp $out/share/java/Furniture.jar:$out/share/java/Textures.jar:$out/share/java/Help.jar ${if stdenv.system == "x86_64-linux" then "-d64" else "-d32"}"
+        --add-flags "-jar $out/share/java/${module}-${version}.jar -cp $out/share/java/Furniture.jar:$out/share/java/Textures.jar:$out/share/java/Help.jar -d${toString stdenv.hostPlatform.parsed.cpu.bits}"
     '';
 
     dontStrip = true;
diff --git a/pkgs/applications/misc/sweethome3d/editors.nix b/pkgs/applications/misc/sweethome3d/editors.nix
index 14285a52e27c..eef5185aaeed 100644
--- a/pkgs/applications/misc/sweethome3d/editors.nix
+++ b/pkgs/applications/misc/sweethome3d/editors.nix
@@ -44,7 +44,7 @@ let
       cp "${editorItem}/share/applications/"* $out/share/applications
       makeWrapper ${jre}/bin/java $out/bin/$exec \
         --prefix XDG_DATA_DIRS : "$XDG_ICON_DIRS:${gtk3.out}/share:${gsettings-desktop-schemas}/share:$out/share:$GSETTINGS_SCHEMAS_PATH" \
-        --add-flags "-jar $out/share/java/${module}-${version}.jar ${if stdenv.system == "x86_64-linux" then "-d64" else "-d32"}"
+        --add-flags "-jar $out/share/java/${module}-${version}.jar -d${toString stdenv.hostPlatform.parsed.cpu.bits}"
     '';
 
     dontStrip = true;
diff --git a/pkgs/applications/misc/xmind/default.nix b/pkgs/applications/misc/xmind/default.nix
index a578c53f0e7c..a12f3dc304ba 100644
--- a/pkgs/applications/misc/xmind/default.nix
+++ b/pkgs/applications/misc/xmind/default.nix
@@ -4,13 +4,13 @@ stdenv.mkDerivation rec {
   name = "xmind-${version}";
   version = "7.5-update1";
 
-  src = if stdenv.system == "i686-linux" then fetchurl {
+  src = if stdenv.hostPlatform.system == "i686-linux" then fetchurl {
     url = "http://dl2.xmind.net/xmind-downloads/${name}-linux_i386.deb";
     sha256 = "04kr6pw0kwy715bp9wcnqnw1k5wl65xa87lhljrskm291p402jy1";
-  } else if stdenv.system == "x86_64-linux" then fetchurl {
+  } else if stdenv.hostPlatform.system == "x86_64-linux" then fetchurl {
     url = "http://dl2.xmind.net/xmind-downloads/${name}-linux_amd64.deb";
     sha256 = "1j2ynhk7p3m3vd6c4mjwpnlzqgfj5c4q3zydab3nfwncwx6gaqj9";
-  } else throw "platform ${stdenv.system} not supported!";
+  } else throw "platform ${stdenv.hostPlatform.system} not supported!";
 
   nativeBuildInputs = [ dpkg makeWrapper ];
 
diff --git a/pkgs/applications/networking/apache-directory-studio/default.nix b/pkgs/applications/networking/apache-directory-studio/default.nix
index d593947f3e62..05dee5b6154c 100644
--- a/pkgs/applications/networking/apache-directory-studio/default.nix
+++ b/pkgs/applications/networking/apache-directory-studio/default.nix
@@ -21,17 +21,17 @@ stdenv.mkDerivation rec {
   version = "2.0.0.v20170904-M13";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "mirror://apache/directory/studio/${version}/ApacheDirectoryStudio-${version}-linux.gtk.x86_64.tar.gz";
         sha256 = "1jfnm6m0ijk31r30hhrxxnizk742dm317iny041p29v897rma7aq";
       }
-    else if stdenv.system == "i686-linux" then
+    else if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         url = "mirror://apache/directory/studio/${version}/ApacheDirectoryStudio-${version}-linux.gtk.x86.tar.gz";
         sha256 = "1bxmgram42qyhrqkgp5k8770f5mjjdd4c6xl4gj09smiycm1qa4n";
       }
-    else throw "Unsupported system: ${stdenv.system}";
+    else throw "Unsupported system: ${stdenv.hostPlatform.system}";
 
   buildInputs = [ makeWrapper ];
 
diff --git a/pkgs/applications/networking/bittorrentsync/generic.nix b/pkgs/applications/networking/bittorrentsync/generic.nix
index dae540ba4260..1075aea8db3a 100644
--- a/pkgs/applications/networking/bittorrentsync/generic.nix
+++ b/pkgs/applications/networking/bittorrentsync/generic.nix
@@ -4,9 +4,9 @@ let
   arch = {
     "x86_64-linux" = "x64";
     "i686-linux" = "i386";
-  }.${stdenv.system} or throwSystem;
+  }.${stdenv.hostPlatform.system} or throwSystem;
   libPath = stdenv.lib.makeLibraryPath [ stdenv.cc.libc ];
-  throwSystem = throw "Unsupported system: ${stdenv.system}";
+  throwSystem = throw "Unsupported system: ${stdenv.hostPlatform.system}";
 in
 
 stdenv.mkDerivation rec {
@@ -20,7 +20,7 @@ stdenv.mkDerivation rec {
       "https://download-cdn.getsync.com/${version}/linux-${arch}/BitTorrent-Sync_${arch}.tar.gz"
       "http://syncapp.bittorrent.com/${version}/btsync_${arch}-${version}.tar.gz"
     ];
-    sha256 = sha256s.${stdenv.system} or throwSystem;
+    sha256 = sha256s.${stdenv.hostPlatform.system} or throwSystem;
   };
 
   dontStrip = true; # Don't strip, otherwise patching the rpaths breaks
diff --git a/pkgs/applications/networking/browsers/firefox-bin/default.nix b/pkgs/applications/networking/browsers/firefox-bin/default.nix
index 1fbcb3d97143..7e92df163afc 100644
--- a/pkgs/applications/networking/browsers/firefox-bin/default.nix
+++ b/pkgs/applications/networking/browsers/firefox-bin/default.nix
@@ -59,7 +59,7 @@ let
     "x86_64-linux" = "linux-x86_64";
   };
 
-  arch = mozillaPlatforms.${stdenv.system};
+  arch = mozillaPlatforms.${stdenv.hostPlatform.system};
 
   isPrefixOf = prefix: string:
     builtins.substring 0 (builtins.stringLength prefix) string == prefix;
diff --git a/pkgs/applications/networking/browsers/firefox/wrapper.nix b/pkgs/applications/networking/browsers/firefox/wrapper.nix
index b64a6cf7ad98..8b06c35fe005 100644
--- a/pkgs/applications/networking/browsers/firefox/wrapper.nix
+++ b/pkgs/applications/networking/browsers/firefox/wrapper.nix
@@ -36,10 +36,10 @@ let
       jre = cfg.jre or false;
       icedtea = cfg.icedtea or false;
       supportsJDK =
-        stdenv.system == "i686-linux" ||
-        stdenv.system == "x86_64-linux" ||
-        stdenv.system == "armv7l-linux" ||
-        stdenv.system == "aarch64-linux";
+        stdenv.hostPlatform.system == "i686-linux" ||
+        stdenv.hostPlatform.system == "x86_64-linux" ||
+        stdenv.hostPlatform.system == "armv7l-linux" ||
+        stdenv.hostPlatform.system == "aarch64-linux";
 
       plugins =
         assert !(jre && icedtea);
diff --git a/pkgs/applications/networking/browsers/mozilla-plugins/flashplayer/default.nix b/pkgs/applications/networking/browsers/mozilla-plugins/flashplayer/default.nix
index 94d0e9e5badd..72e1a08f40b3 100644
--- a/pkgs/applications/networking/browsers/mozilla-plugins/flashplayer/default.nix
+++ b/pkgs/applications/networking/browsers/mozilla-plugins/flashplayer/default.nix
@@ -60,13 +60,13 @@
 
 let
   arch =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       "x86_64"
-    else if stdenv.system == "i686-linux"   then
+    else if stdenv.hostPlatform.system == "i686-linux"   then
       "i386"
     else throw "Flash Player is not supported on this platform";
   lib_suffix =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
       "64"
     else
       "";
diff --git a/pkgs/applications/networking/browsers/mozilla-plugins/google-talk-plugin/default.nix b/pkgs/applications/networking/browsers/mozilla-plugins/google-talk-plugin/default.nix
index a172e0e8d5d9..71b5161c1e39 100644
--- a/pkgs/applications/networking/browsers/mozilla-plugins/google-talk-plugin/default.nix
+++ b/pkgs/applications/networking/browsers/mozilla-plugins/google-talk-plugin/default.nix
@@ -54,12 +54,12 @@ stdenv.mkDerivation rec {
   version = "5.41.3.0";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "${baseURL}/google-talkplugin_${version}-1_amd64.deb";
         sha1 = "0bbc3d6997ba22ce712d93e5bc336c894b54fc81";
       }
-    else if stdenv.system == "i686-linux" then
+    else if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         url = "${baseURL}/google-talkplugin_${version}-1_i386.deb";
         sha1 = "6eae0544858f85c68b0cc46d7786e990bd94f139";
diff --git a/pkgs/applications/networking/browsers/mozilla-plugins/trezor/default.nix b/pkgs/applications/networking/browsers/mozilla-plugins/trezor/default.nix
index 3d4e0fc00225..5f7f601b3545 100644
--- a/pkgs/applications/networking/browsers/mozilla-plugins/trezor/default.nix
+++ b/pkgs/applications/networking/browsers/mozilla-plugins/trezor/default.nix
@@ -8,7 +8,7 @@ stdenv.mkDerivation {
   };
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url    = https://mytrezor.com/data/plugin/1.0.5/browser-plugin-trezor_1.0.5_amd64.deb;
         sha256 = "0097h4v88yca4aayzprrh4pk03xvvj7ncz2mi83chm81gsr2v67z";
diff --git a/pkgs/applications/networking/browsers/tor-browser-bundle-bin/default.nix b/pkgs/applications/networking/browsers/tor-browser-bundle-bin/default.nix
index de6766709131..f5f88cdfc027 100644
--- a/pkgs/applications/networking/browsers/tor-browser-bundle-bin/default.nix
+++ b/pkgs/applications/networking/browsers/tor-browser-bundle-bin/default.nix
@@ -125,7 +125,7 @@ stdenv.mkDerivation rec {
   name = "tor-browser-bundle-bin-${version}";
   inherit version;
 
-  src = srcs."${stdenv.system}" or (throw "unsupported system: ${stdenv.system}");
+  src = srcs."${stdenv.hostPlatform.system}" or (throw "unsupported system: ${stdenv.hostPlatform.system}");
 
   preferLocalBuild = true;
   allowSubstitutes = false;
diff --git a/pkgs/applications/networking/dropbox/default.nix b/pkgs/applications/networking/dropbox/default.nix
index 3450ad720486..047ad734bd40 100644
--- a/pkgs/applications/networking/dropbox/default.nix
+++ b/pkgs/applications/networking/dropbox/default.nix
@@ -2,7 +2,7 @@
 
 let platforms = [ "i686-linux" "x86_64-linux" ]; in
 
-assert lib.elem stdenv.system platforms;
+assert lib.elem stdenv.hostPlatform.system platforms;
 
 # Dropbox client to bootstrap installation.
 # The client is self-updating, so the actual version may be newer.
@@ -12,7 +12,7 @@ let
   arch = {
     "x86_64-linux" = "x86_64";
     "i686-linux"   = "x86";
-  }.${stdenv.system};
+  }.${stdenv.hostPlatform.system};
 
   installer = "https://clientupdates.dropboxstatic.com/dbx-releng/client/dropbox-lnx.${arch}-${version}.tar.gz";
 in
diff --git a/pkgs/applications/networking/instant-messengers/franz/default.nix b/pkgs/applications/networking/instant-messengers/franz/default.nix
index b253e41ae7d8..2f3870d78994 100644
--- a/pkgs/applications/networking/instant-messengers/franz/default.nix
+++ b/pkgs/applications/networking/instant-messengers/franz/default.nix
@@ -3,7 +3,7 @@
 , gnome2, dbus, nss, nspr, alsaLib, cups, expat, udev, libnotify, xdg_utils }:
 
 let
-  bits = if stdenv.system == "x86_64-linux" then "x64"
+  bits = if stdenv.hostPlatform.system == "x86_64-linux" then "x64"
          else "ia32";
 
   version = "4.0.4";
diff --git a/pkgs/applications/networking/instant-messengers/mattermost-desktop/default.nix b/pkgs/applications/networking/instant-messengers/mattermost-desktop/default.nix
index a9ce8a96f970..109893850de1 100644
--- a/pkgs/applications/networking/instant-messengers/mattermost-desktop/default.nix
+++ b/pkgs/applications/networking/instant-messengers/mattermost-desktop/default.nix
@@ -41,18 +41,18 @@ in
     version = "4.1.2";
 
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = "https://releases.mattermost.com/desktop/${version}/${name}-linux-x64.tar.gz";
           sha256 = "16dn6870bs1nfl2082ym9gwvmqb3i5sli48qprap80p7riph6k9s";
         }
-      else if stdenv.system == "i686-linux" then
+      else if stdenv.hostPlatform.system == "i686-linux" then
         fetchurl {
           url = "https://releases.mattermost.com/desktop/${version}/${name}-linux-ia32.tar.gz";
           sha256 = "145zb1l37fa2slfrrlprlwzcc5km3plxs374yhgix25mlg2afkqr";
         }
       else
-        throw "Mattermost-Desktop is not currently supported on ${stdenv.system}";
+        throw "Mattermost-Desktop is not currently supported on ${stdenv.hostPlatform.system}";
 
     phases = [ "unpackPhase" "installPhase" ];
     installPhase = ''
diff --git a/pkgs/applications/networking/instant-messengers/rambox/sencha/bare.nix b/pkgs/applications/networking/instant-messengers/rambox/sencha/bare.nix
index ca82f30e2d1f..af92462a2a49 100644
--- a/pkgs/applications/networking/instant-messengers/rambox/sencha/bare.nix
+++ b/pkgs/applications/networking/instant-messengers/rambox/sencha/bare.nix
@@ -18,7 +18,7 @@ stdenv.mkDerivation rec {
   inherit version;
 
   name = "sencha-bare-${version}";
-  src = srcs.${stdenv.system};
+  src = srcs.${stdenv.hostPlatform.system};
 
   nativeBuildInputs = [ gzip which unzip ];
   buildInputs = [ jdk ];
diff --git a/pkgs/applications/networking/instant-messengers/skypeforlinux/default.nix b/pkgs/applications/networking/instant-messengers/skypeforlinux/default.nix
index d728c8d95cca..eaa9103a7b64 100644
--- a/pkgs/applications/networking/instant-messengers/skypeforlinux/default.nix
+++ b/pkgs/applications/networking/instant-messengers/skypeforlinux/default.nix
@@ -53,13 +53,13 @@ let
   ] + ":${stdenv.cc.cc.lib}/lib64";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://repo.skype.com/deb/pool/main/s/skypeforlinux/skypeforlinux_${version}_amd64.deb";
         sha256 = "1kydf71qbz35dx4674h3nxfx8a88k620217906i54ic4qq2mgy2x";
       }
     else
-      throw "Skype for linux is not supported on ${stdenv.system}";
+      throw "Skype for linux is not supported on ${stdenv.hostPlatform.system}";
 
 in stdenv.mkDerivation {
   name = "skypeforlinux-${version}";
diff --git a/pkgs/applications/networking/instant-messengers/slack/default.nix b/pkgs/applications/networking/instant-messengers/slack/default.nix
index bcf887808750..af2030a20b8a 100644
--- a/pkgs/applications/networking/instant-messengers/slack/default.nix
+++ b/pkgs/applications/networking/instant-messengers/slack/default.nix
@@ -44,13 +44,13 @@ let
   ] + ":${stdenv.cc.cc.lib}/lib64";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://downloads.slack-edge.com/linux_releases/slack-desktop-${version}-amd64.deb";
         sha256 = "095dpkwvvnwlxsglyg6wi9126wpalzi736b6g6j3bd6d93z9afah";
       }
     else
-      throw "Slack is not supported on ${stdenv.system}";
+      throw "Slack is not supported on ${stdenv.hostPlatform.system}";
 
 in stdenv.mkDerivation {
   name = "slack-${version}";
diff --git a/pkgs/applications/networking/instant-messengers/wire-desktop/default.nix b/pkgs/applications/networking/instant-messengers/wire-desktop/default.nix
index 0745836271ae..0985f139238e 100644
--- a/pkgs/applications/networking/instant-messengers/wire-desktop/default.nix
+++ b/pkgs/applications/networking/instant-messengers/wire-desktop/default.nix
@@ -44,12 +44,12 @@ let
   plat = {
     "i686-linux" = "i386";
     "x86_64-linux" = "amd64";
-  }.${stdenv.system};
+  }.${stdenv.hostPlatform.system};
 
   sha256 = {
     "i686-linux" = "071ddh2d8wmiybwafwyb97962zj358l0fq7g2r44231653sgybvq";
     "x86_64-linux" = "0qp9ms94smnm7k47b0n0jdzvnm1b7gj25hyinsfc6lghrb6jqw3r";
-  }.${stdenv.system};
+  }.${stdenv.hostPlatform.system};
 
 in
   stdenv.mkDerivation rec {
diff --git a/pkgs/applications/networking/instant-messengers/zoom-us/default.nix b/pkgs/applications/networking/instant-messengers/zoom-us/default.nix
index afc6f03edb4a..882215c50c5c 100644
--- a/pkgs/applications/networking/instant-messengers/zoom-us/default.nix
+++ b/pkgs/applications/networking/instant-messengers/zoom-us/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, system, makeWrapper, makeDesktopItem, autoPatchelfHook, env
+{ stdenv, fetchurl, makeWrapper, makeDesktopItem, autoPatchelfHook, env
 # Dynamic libraries
 , dbus, glib, libGL, libX11, libXfixes, libuuid, libxcb, qtbase, qtdeclarative
 , qtimageformats, qtlocation, qtquickcontrols, qtquickcontrols2, qtscript, qtsvg
@@ -31,7 +31,7 @@ let
 in stdenv.mkDerivation {
   name = "zoom-us-${version}";
 
-  src = srcs.${system};
+  src = srcs.${stdenv.hostPlatform.system};
 
   nativeBuildInputs = [ autoPatchelfHook makeWrapper ];
 
diff --git a/pkgs/applications/networking/insync/default.nix b/pkgs/applications/networking/insync/default.nix
index e718dc6562fb..fee19de0e8d7 100644
--- a/pkgs/applications/networking/insync/default.nix
+++ b/pkgs/applications/networking/insync/default.nix
@@ -4,13 +4,13 @@ stdenv.mkDerivation rec {
   name = "insync-${version}";
   version = "1.4.5.37069";
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "http://s.insynchq.com/builds/insync-portable_${version}_amd64.tar.bz2";
         sha256 = "0mkqgpq4isngkj20c0ygmxf4cj975d446svhwvl3cqdrjkjm1ybd";
       }
     else
-      throw "${name} is not supported on ${stdenv.system}";
+      throw "${name} is not supported on ${stdenv.hostPlatform.system}";
 
   buildInputs = [ makeWrapper ];
 
diff --git a/pkgs/applications/networking/mailreaders/nylas-mail-bin/default.nix b/pkgs/applications/networking/mailreaders/nylas-mail-bin/default.nix
index 3376eebe5dc9..3d8673a87a1b 100644
--- a/pkgs/applications/networking/mailreaders/nylas-mail-bin/default.nix
+++ b/pkgs/applications/networking/mailreaders/nylas-mail-bin/default.nix
@@ -33,13 +33,13 @@ stdenv.mkDerivation rec {
   subVersion = "fec7941";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://edgehill.s3.amazonaws.com/${version}-${subVersion}/linux-deb/x64/NylasMail.deb";
         sha256 = "40060aa1dc3b5187b8ed4a07b9de3427e3c5a291df98c2c82395647fa2aa4ada";
       }
     else
-      throw "NylasMail is not supported on ${stdenv.system}";
+      throw "NylasMail is not supported on ${stdenv.hostPlatform.system}";
 
   propagatedBuildInputs = [
     alsaLib
diff --git a/pkgs/applications/networking/mailreaders/thunderbird-bin/default.nix b/pkgs/applications/networking/mailreaders/thunderbird-bin/default.nix
index b9b553f94472..cf68a2686194 100644
--- a/pkgs/applications/networking/mailreaders/thunderbird-bin/default.nix
+++ b/pkgs/applications/networking/mailreaders/thunderbird-bin/default.nix
@@ -47,7 +47,7 @@
 with (import ./release_sources.nix);
 
 let
-  arch = if stdenv.system == "i686-linux"
+  arch = if stdenv.hostPlatform.system == "i686-linux"
     then "linux-i686"
     else "linux-x86_64";
 
diff --git a/pkgs/applications/networking/p2p/frostwire/default.nix b/pkgs/applications/networking/p2p/frostwire/default.nix
index 7b854fce6c55..40ff91e792b4 100644
--- a/pkgs/applications/networking/p2p/frostwire/default.nix
+++ b/pkgs/applications/networking/p2p/frostwire/default.nix
@@ -75,7 +75,7 @@ in stdenv.mkDerivation {
     cp ${ { x86_64-darwin = "desktop/lib/native/*.dylib";
             x86_64-linux  = "desktop/lib/native/lib{jlibtorrent,SystemUtilities}.so";
             i686-linux    = "desktop/lib/native/lib{jlibtorrent,SystemUtilities}X86.so";
-          }.${stdenv.system} or (throw "unsupported system ${stdenv.system}")
+          }.${stdenv.hostPlatform.system} or (throw "unsupported system ${stdenv.hostPlatform.system}")
         } $out/lib
 
     cp -dpR ${desktopItem}/share $out
diff --git a/pkgs/applications/networking/p2p/soulseekqt/default.nix b/pkgs/applications/networking/p2p/soulseekqt/default.nix
index 44e434aa8ee9..12ed680482f6 100644
--- a/pkgs/applications/networking/p2p/soulseekqt/default.nix
+++ b/pkgs/applications/networking/p2p/soulseekqt/default.nix
@@ -37,7 +37,7 @@ in stdenv.mkDerivation rec {
 
   name = "soulseekqt-${version}";
   inherit version;
-  src = srcs."${stdenv.system}" or (throw "unsupported system: ${stdenv.system}");
+  src = srcs."${stdenv.hostPlatform.system}" or (throw "unsupported system: ${stdenv.hostPlatform.system}");
 
   dontBuild = true;
 
diff --git a/pkgs/applications/networking/remote/anydesk/default.nix b/pkgs/applications/networking/remote/anydesk/default.nix
index 0f107936be6f..cb3814b55f19 100644
--- a/pkgs/applications/networking/remote/anydesk/default.nix
+++ b/pkgs/applications/networking/remote/anydesk/default.nix
@@ -6,12 +6,12 @@ let
   sha256 = {
     "x86_64-linux" = "0g19sac4j3m1nf400vn6qcww7prqg2p4k4zsj74i109kk1396aa2";
     "i686-linux"   = "1dd4ai2pclav9g872xil3x67bxy32gvz9pb3w76383pcsdh5zh45";
-  }."${stdenv.system}" or (throw "system ${stdenv.system} not supported");
+  }."${stdenv.hostPlatform.system}" or (throw "system ${stdenv.hostPlatform.system} not supported");
 
   arch = {
     "x86_64-linux" = "amd64";
     "i686-linux"   = "i686";
-  }."${stdenv.system}" or (throw "system ${stdenv.system} not supported");
+  }."${stdenv.hostPlatform.system}" or (throw "system ${stdenv.hostPlatform.system} not supported");
 
   description = "Desktop sharing application, providing remote support and online meetings";
 
diff --git a/pkgs/applications/networking/resilio-sync/default.nix b/pkgs/applications/networking/resilio-sync/default.nix
index 0db18e77bfa6..b59219d99366 100644
--- a/pkgs/applications/networking/resilio-sync/default.nix
+++ b/pkgs/applications/networking/resilio-sync/default.nix
@@ -4,7 +4,7 @@ let
   arch = {
     "x86_64-linux" = "x64";
     "i686-linux" = "i386";
-  }.${stdenv.system} or (throw "Unsupported system: ${stdenv.system}");
+  }.${stdenv.hostPlatform.system} or (throw "Unsupported system: ${stdenv.hostPlatform.system}");
   libPath = stdenv.lib.makeLibraryPath [ stdenv.cc.libc ];
 
 in stdenv.mkDerivation rec {
@@ -16,7 +16,7 @@ in stdenv.mkDerivation rec {
     sha256 = {
       "x86_64-linux" = "0041axi9carspkfaxvyirfvsa29zz55al01x90nh93nzxvpvywsz";
       "i686-linux"   = "1ar36lp4f6a1z9i82g3gpak4q4ny09faqxdd59q1pvfzq25ypdhs";
-    }.${stdenv.system};
+    }.${stdenv.hostPlatform.system};
   };
 
   dontStrip = true; # Don't strip, otherwise patching the rpaths breaks
diff --git a/pkgs/applications/networking/spideroak/default.nix b/pkgs/applications/networking/spideroak/default.nix
index c1f3d62af737..c07ad715afd2 100644
--- a/pkgs/applications/networking/spideroak/default.nix
+++ b/pkgs/applications/networking/spideroak/default.nix
@@ -4,17 +4,17 @@
 }:
 
 let
-  arch = if stdenv.system == "x86_64-linux" then "x64"
-    else if stdenv.system == "i686-linux" then "x86"
-    else throw "Spideroak client for: ${stdenv.system} not supported!";
+  arch = if stdenv.hostPlatform.system == "x86_64-linux" then "x64"
+    else if stdenv.hostPlatform.system == "i686-linux" then "x86"
+    else throw "Spideroak client for: ${stdenv.hostPlatform.system} not supported!";
 
-  interpreter = if stdenv.system == "x86_64-linux" then "ld-linux-x86-64.so.2"
-    else if stdenv.system == "i686-linux" then "ld-linux.so.2"
-    else throw "Spideroak client for: ${stdenv.system} not supported!";
+  interpreter = if stdenv.hostPlatform.system == "x86_64-linux" then "ld-linux-x86-64.so.2"
+    else if stdenv.hostPlatform.system == "i686-linux" then "ld-linux.so.2"
+    else throw "Spideroak client for: ${stdenv.hostPlatform.system} not supported!";
 
-  sha256 = if stdenv.system == "x86_64-linux" then "a88e5a8fe4a565ac500668bd53cf5784752d7c9253304ddce39ee7b01d078533"
-    else if stdenv.system == "i686-linux" then "668f3b83a974a3877d16c8743c233a427ea0a44ab84b7f9aec19a2995db66c16"
-    else throw "Spideroak client for: ${stdenv.system} not supported!";
+  sha256 = if stdenv.hostPlatform.system == "x86_64-linux" then "a88e5a8fe4a565ac500668bd53cf5784752d7c9253304ddce39ee7b01d078533"
+    else if stdenv.hostPlatform.system == "i686-linux" then "668f3b83a974a3877d16c8743c233a427ea0a44ab84b7f9aec19a2995db66c16"
+    else throw "Spideroak client for: ${stdenv.hostPlatform.system} not supported!";
 
   ldpath = stdenv.lib.makeLibraryPath [
     fontconfig freetype glib libICE libSM
diff --git a/pkgs/applications/networking/super-productivity/default.nix b/pkgs/applications/networking/super-productivity/default.nix
index 59872afaad93..9bb4254c64a2 100644
--- a/pkgs/applications/networking/super-productivity/default.nix
+++ b/pkgs/applications/networking/super-productivity/default.nix
@@ -44,13 +44,13 @@ let
   ] + ":${stdenv.cc.cc.lib}/lib64";
 
   src =
-    if stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "https://github.com/johannesjo/super-productivity/releases/download/v${version}/superProductivity_${version}_amd64.deb";
         sha256 = "0jfi0lfijnhij9jvkhxgyvq8m1jzaym8n1c7707fv3hjh1h0vxn1";
       }
     else
-      throw "super-productivity is not supported on ${stdenv.system}";
+      throw "super-productivity is not supported on ${stdenv.hostPlatform.system}";
 
 in stdenv.mkDerivation {
   name = "super-productivity-${version}";
diff --git a/pkgs/applications/office/jameica/default.nix b/pkgs/applications/office/jameica/default.nix
index fdc6c58213a1..8d17ef2acaa4 100644
--- a/pkgs/applications/office/jameica/default.nix
+++ b/pkgs/applications/office/jameica/default.nix
@@ -6,10 +6,10 @@ let
   version = "${_version}-${_build}";
   name = "jameica-${version}";
 
-  swtSystem = if stdenv.system == "i686-linux" then "linux"
-  else if stdenv.system == "x86_64-linux" then "linux64"
-  else if stdenv.system == "x86_64-darwin" then "macos64"
-  else throw "Unsupported system: ${stdenv.system}";
+  swtSystem = if stdenv.hostPlatform.system == "i686-linux" then "linux"
+  else if stdenv.hostPlatform.system == "x86_64-linux" then "linux64"
+  else if stdenv.hostPlatform.system == "x86_64-darwin" then "macos64"
+  else throw "Unsupported system: ${stdenv.hostPlatform.system}";
 
   desktopItem = makeDesktopItem {
     name = "jameica";
diff --git a/pkgs/applications/office/mendeley/default.nix b/pkgs/applications/office/mendeley/default.nix
index 693fa63661b5..5b6271db83bd 100644
--- a/pkgs/applications/office/mendeley/default.nix
+++ b/pkgs/applications/office/mendeley/default.nix
@@ -37,7 +37,7 @@
 let
   arch32 = "i686-linux";
 
-  arch = if stdenv.system == arch32
+  arch = if stdenv.hostPlatform.system == arch32
     then "i386"
     else "amd64";
 
@@ -46,7 +46,7 @@ let
   version = "${shortVersion}_${arch}";
 
   url = "http://desktop-download.mendeley.com/download/apt/pool/main/m/mendeleydesktop/mendeleydesktop_${version}.deb";
-  sha256 = if stdenv.system == arch32
+  sha256 = if stdenv.hostPlatform.system == arch32
     then "0fcyl5i8xdgb5j0x1643qc0j74d8p11jczvqmgqkqh0wgid1y1ad"
     else "1dzwa2cnn9xakrhhq159fhh71gw5wlbf017rrikdlia694m8akq6";
 
diff --git a/pkgs/applications/office/moneyplex/default.nix b/pkgs/applications/office/moneyplex/default.nix
index 47d2ecc81ea3..9f4ed80e6d80 100644
--- a/pkgs/applications/office/moneyplex/default.nix
+++ b/pkgs/applications/office/moneyplex/default.nix
@@ -21,8 +21,8 @@ stdenv.mkDerivation rec {
   name = "moneyplex-${version}";
   version = "16.0.22424";
 
-  src = fetchurl (if stdenv.system == "i686-linux" then src_i686
-                  else if stdenv.system == "x86_64-linux" then src_x86_64
+  src = fetchurl (if stdenv.hostPlatform.system == "i686-linux" then src_i686
+                  else if stdenv.hostPlatform.system == "x86_64-linux" then src_x86_64
                   else throw "moneyplex requires i686-linux or x86_64-linux");
 
 
diff --git a/pkgs/applications/office/wpsoffice/default.nix b/pkgs/applications/office/wpsoffice/default.nix
index 46faf9ba651e..4c83d67f7cda 100644
--- a/pkgs/applications/office/wpsoffice/default.nix
+++ b/pkgs/applications/office/wpsoffice/default.nix
@@ -3,7 +3,7 @@
 , zlib, libpng12, libICE, libXrender, cups }:
 
 let
-  bits = if stdenv.system == "x86_64-linux" then "x86_64"
+  bits = if stdenv.hostPlatform.system == "x86_64-linux" then "x86_64"
          else "x86";
 
   version = "10.1.0.5672";
diff --git a/pkgs/applications/science/electronics/eagle/eagle7.nix b/pkgs/applications/science/electronics/eagle/eagle7.nix
index 9b8827187b26..d5720440f7cc 100644
--- a/pkgs/applications/science/electronics/eagle/eagle7.nix
+++ b/pkgs/applications/science/electronics/eagle/eagle7.nix
@@ -17,18 +17,18 @@ stdenv.mkDerivation rec {
   version = "7.7.0";
 
   src =
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       fetchurl {
         url = "ftp://ftp.cadsoft.de/eagle/program/7.7/eagle-lin32-${version}.run";
         sha256 = "16fa66p77xigc7zvzfm7737mllrcs6nrgk2p7wvkjw3p9lvbz7z1";
       }
-    else if stdenv.system == "x86_64-linux" then
+    else if stdenv.hostPlatform.system == "x86_64-linux" then
       fetchurl {
         url = "ftp://ftp.cadsoft.de/eagle/program/7.7/eagle-lin64-${version}.run";
         sha256 = "18dcn6wqph1sqh0ah98qzfi05wip8a8ifbkaq79iskbrsi8iqnrg";
       }
     else
-      throw "Unsupported system: ${stdenv.system}";
+      throw "Unsupported system: ${stdenv.hostPlatform.system}";
 
   desktopItem = makeDesktopItem {
     name = "eagle";
diff --git a/pkgs/applications/science/logic/isabelle/default.nix b/pkgs/applications/science/logic/isabelle/default.nix
index ae04c11d9590..ffe508569553 100644
--- a/pkgs/applications/science/logic/isabelle/default.nix
+++ b/pkgs/applications/science/logic/isabelle/default.nix
@@ -48,7 +48,7 @@ stdenv.mkDerivation {
       rm -rf $comp/x86*
     done
     '' + (if ! stdenv.isLinux then "" else ''
-    arch=${if stdenv.system == "x86_64-linux" then "x86_64-linux" else "x86-linux"}
+    arch=${if stdenv.hostPlatform.system == "x86_64-linux" then "x86_64-linux" else "x86-linux"}
     for f in contrib/*/$arch/{bash_process,epclextract,eprover,nunchaku,SPASS}; do
       patchelf --set-interpreter $(cat ${stdenv.cc}/nix-support/dynamic-linker) "$f"
     done
diff --git a/pkgs/applications/science/logic/saw-tools/default.nix b/pkgs/applications/science/logic/saw-tools/default.nix
index 65d2b4d91c30..32ebdad51d94 100644
--- a/pkgs/applications/science/logic/saw-tools/default.nix
+++ b/pkgs/applications/science/logic/saw-tools/default.nix
@@ -12,7 +12,7 @@ let
   url = "https://github.com/GaloisInc/saw-script/releases/download";
 
   saw-bin =
-    if stdenv.system == "i686-linux"
+    if stdenv.hostPlatform.system == "i686-linux"
     then fetchurl {
       url    = url + "/v0.1.1-dev/saw-0.1.1-dev-2015-07-31-CentOS6-32.tar.gz";
       sha256 = "126iag5nnvndi78c921z7vjrjfwcspn1hlxwwhzmqm4rvbhhr9v9";
diff --git a/pkgs/applications/science/math/mathematica/10.nix b/pkgs/applications/science/math/mathematica/10.nix
index 4884ee1f93ab..c6802c3719e9 100644
--- a/pkgs/applications/science/math/mathematica/10.nix
+++ b/pkgs/applications/science/math/mathematica/10.nix
@@ -18,7 +18,7 @@
 
 let
   platform =
-    if stdenv.system == "i686-linux" || stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" || stdenv.hostPlatform.system == "x86_64-linux" then
       "Linux"
     else
       throw "Mathematica requires i686-linux or x86_64 linux";
@@ -70,7 +70,7 @@ stdenv.mkDerivation rec {
   ]);
 
   ldpath = stdenv.lib.makeLibraryPath buildInputs
-    + stdenv.lib.optionalString (stdenv.system == "x86_64-linux")
+    + stdenv.lib.optionalString (stdenv.hostPlatform.system == "x86_64-linux")
       (":" + stdenv.lib.makeSearchPathOutput "lib" "lib64" buildInputs);
 
   phases = "unpackPhase installPhase fixupPhase";
diff --git a/pkgs/applications/science/math/mathematica/9.nix b/pkgs/applications/science/math/mathematica/9.nix
index d60feb54695d..1023e7ca3d5c 100644
--- a/pkgs/applications/science/math/mathematica/9.nix
+++ b/pkgs/applications/science/math/mathematica/9.nix
@@ -16,7 +16,7 @@
 
 let
   platform =
-    if stdenv.system == "i686-linux" || stdenv.system == "x86_64-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" || stdenv.hostPlatform.system == "x86_64-linux" then
       "Linux"
     else
       throw "Mathematica requires i686-linux or x86_64 linux";
@@ -60,7 +60,7 @@ stdenv.mkDerivation rec {
   ]);
 
   ldpath = stdenv.lib.makeLibraryPath buildInputs
-    + stdenv.lib.optionalString (stdenv.system == "x86_64-linux")
+    + stdenv.lib.optionalString (stdenv.hostPlatform.system == "x86_64-linux")
       (":" + stdenv.lib.makeSearchPathOutput "lib" "lib64" buildInputs);
 
   phases = "unpackPhase installPhase fixupPhase";
diff --git a/pkgs/applications/science/math/mathematica/default.nix b/pkgs/applications/science/math/mathematica/default.nix
index fa4ff8b00687..165a56605579 100644
--- a/pkgs/applications/science/math/mathematica/default.nix
+++ b/pkgs/applications/science/math/mathematica/default.nix
@@ -69,7 +69,7 @@ stdenv.mkDerivation rec {
   ]);
 
   ldpath = stdenv.lib.makeLibraryPath buildInputs
-    + stdenv.lib.optionalString (stdenv.system == "x86_64-linux")
+    + stdenv.lib.optionalString (stdenv.hostPlatform.system == "x86_64-linux")
       (":" + stdenv.lib.makeSearchPathOutput "lib" "lib64" buildInputs);
 
   phases = "unpackPhase installPhase fixupPhase";
diff --git a/pkgs/applications/science/math/scilab-bin/default.nix b/pkgs/applications/science/math/scilab-bin/default.nix
index dacd3e730736..54b262fe5058 100644
--- a/pkgs/applications/science/math/scilab-bin/default.nix
+++ b/pkgs/applications/science/math/scilab-bin/default.nix
@@ -10,9 +10,9 @@ let
   badArch = throw "${name} requires i686-linux or x86_64-linux";
 
   architecture =
-    if stdenv.system == "i686-linux" then
+    if stdenv.hostPlatform.system == "i686-linux" then
       "i686"
-    else if stdenv.system == "x86_64-linux" then
+    else if stdenv.hostPlatform.system == "x86_64-linux" then
       "x86_64"
     else
       badArch;
@@ -23,9 +23,9 @@ stdenv.mkDerivation rec {
   src = fetchurl {
     url = "https://www.scilab.org/download/${ver}/scilab-${ver}.bin.linux-${architecture}.tar.gz";
     sha256 =
-      if stdenv.system == "i686-linux" then
+      if stdenv.hostPlatform.system == "i686-linux" then
         "0fgjc2ak3b2qi6yin3fy50qwk2bcj0zbz1h4lyyic9n1n1qcliib"
-      else if stdenv.system == "x86_64-linux" then
+      else if stdenv.hostPlatform.system == "x86_64-linux" then
         "1scswlznc14vyzg0gqa1q9gcpwx05kz1sbn563463mzkdp7nd35d"
       else
         badArch;
diff --git a/pkgs/applications/search/recoll/default.nix b/pkgs/applications/search/recoll/default.nix
index 01a4f4023023..e56284ac5c53 100644
--- a/pkgs/applications/search/recoll/default.nix
+++ b/pkgs/applications/search/recoll/default.nix
@@ -5,7 +5,7 @@
 , ghostscript, gawk, gnugrep, gnused, gnutar, gzip, libiconv, zlib
 , withGui ? true }:
 
-assert stdenv.system != "powerpc-linux";
+assert stdenv.hostPlatform.system != "powerpc-linux";
 
 stdenv.mkDerivation rec {
   ver = "1.23.7";
diff --git a/pkgs/applications/video/lightworks/default.nix b/pkgs/applications/video/lightworks/default.nix
index 64a967001b57..4bfd9e790070 100644
--- a/pkgs/applications/video/lightworks/default.nix
+++ b/pkgs/applications/video/lightworks/default.nix
@@ -23,12 +23,12 @@ let
     name = "lightworks-${version}";
     
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = "http://downloads.lwks.com/v14/lwks-14.0.0-amd64.deb";
           sha256 = "66eb9f9678d979db76199f1c99a71df0ddc017bb47dfda976b508849ab305033";
         }
-      else throw "${name} is not supported on ${stdenv.system}";
+      else throw "${name} is not supported on ${stdenv.hostPlatform.system}";
 
     buildInputs = [ dpkg makeWrapper ];
 
diff --git a/pkgs/applications/video/mplayer/default.nix b/pkgs/applications/video/mplayer/default.nix
index 02a0c2c0ec49..e017e7cc0015 100644
--- a/pkgs/applications/video/mplayer/default.nix
+++ b/pkgs/applications/video/mplayer/default.nix
@@ -60,13 +60,13 @@ let
     let
       dir = http://www.mplayerhq.hu/MPlayer/releases/codecs/;
     in
-    if stdenv.system == "i686-linux" then fetchurl {
+    if stdenv.hostPlatform.system == "i686-linux" then fetchurl {
       url = "${dir}/essential-20071007.tar.bz2";
       sha256 = "18vls12n12rjw0mzw4pkp9vpcfmd1c21rzha19d7zil4hn7fs2ic";
-    } else if stdenv.system == "x86_64-linux" then fetchurl {
+    } else if stdenv.hostPlatform.system == "x86_64-linux" then fetchurl {
       url = "${dir}/essential-amd64-20071007.tar.bz2";
       sha256 = "13xf5b92w1ra5hw00ck151lypbmnylrnznq9hhb0sj36z5wz290x";
-    } else if stdenv.system == "powerpc-linux" then fetchurl {
+    } else if stdenv.hostPlatform.system == "powerpc-linux" then fetchurl {
       url = "${dir}/essential-ppc-20071007.tar.bz2";
       sha256 = "18mlj8dp4wnz42xbhdk1jlz2ygra6fbln9wyrcyvynxh96g1871z";
     } else null;
diff --git a/pkgs/applications/video/webtorrent_desktop/default.nix b/pkgs/applications/video/webtorrent_desktop/default.nix
index c99aed0c1afb..086190000ab4 100644
--- a/pkgs/applications/video/webtorrent_desktop/default.nix
+++ b/pkgs/applications/video/webtorrent_desktop/default.nix
@@ -42,13 +42,13 @@
     version = "0.20.0";
 
     src =
-      if stdenv.system == "x86_64-linux" then
+      if stdenv.hostPlatform.system == "x86_64-linux" then
         fetchurl {
           url = "https://github.com/webtorrent/webtorrent-desktop/releases/download/v0.20.0/webtorrent-desktop_${version}-1_amd64.deb";
           sha256 = "1kkrnbimiip5pn2nwpln35bbdda9gc3cgrjwphq4fqasbjf2781k";
         }
         else
-          throw "Webtorrent is not currently supported on ${stdenv.system}";
+          throw "Webtorrent is not currently supported on ${stdenv.hostPlatform.system}";
     phases = [ "unpackPhase" "installPhase" ];
     nativeBuildInputs = [ dpkg ];
     unpackPhase = "dpkg-deb -x $src .";
diff --git a/pkgs/applications/virtualization/qemu/default.nix b/pkgs/applications/virtualization/qemu/default.nix
index f9058ef89b65..bbb2a099666b 100644
--- a/pkgs/applications/virtualization/qemu/default.nix
+++ b/pkgs/applications/virtualization/qemu/default.nix
@@ -22,7 +22,7 @@
 
 with stdenv.lib;
 let
-  audio = optionalString (hasSuffix "linux" stdenv.system) "alsa,"
+  audio = optionalString (hasSuffix "linux" stdenv.hostPlatform.system) "alsa,"
     + optionalString pulseSupport "pa,"
     + optionalString sdlSupport "sdl,";
 
diff --git a/pkgs/applications/virtualization/virtualbox/guest-additions/default.nix b/pkgs/applications/virtualization/virtualbox/guest-additions/default.nix
index dcc58b04c8e3..cb7bcad3592d 100644
--- a/pkgs/applications/virtualization/virtualbox/guest-additions/default.nix
+++ b/pkgs/applications/virtualization/virtualbox/guest-additions/default.nix
@@ -44,23 +44,23 @@ stdenv.mkDerivation {
   '';
 
   buildCommand = with xorg; ''
-    ${if stdenv.system == "i686-linux" || stdenv.system == "x86_64-linux" then ''
+    ${if stdenv.hostPlatform.system == "i686-linux" || stdenv.hostPlatform.system == "x86_64-linux" then ''
         isoinfo -J -i $src -x /VBoxLinuxAdditions.run > ./VBoxLinuxAdditions.run
         chmod 755 ./VBoxLinuxAdditions.run
         ./VBoxLinuxAdditions.run --noexec --keep
       ''
-      else throw ("Architecture: "+stdenv.system+" not supported for VirtualBox guest additions")
+      else throw ("Architecture: "+stdenv.hostPlatform.system+" not supported for VirtualBox guest additions")
     }
 
     # Unpack files
     cd install
-    ${if stdenv.system == "i686-linux" then ''
+    ${if stdenv.hostPlatform.system == "i686-linux" then ''
         tar xfvj VBoxGuestAdditions-x86.tar.bz2
       ''
-      else if stdenv.system == "x86_64-linux" then ''
+      else if stdenv.hostPlatform.system == "x86_64-linux" then ''
         tar xfvj VBoxGuestAdditions-amd64.tar.bz2
       ''
-      else throw ("Architecture: "+stdenv.system+" not supported for VirtualBox guest additions")
+      else throw ("Architecture: "+stdenv.hostPlatform.system+" not supported for VirtualBox guest additions")
     }
 
     cd ../
@@ -81,13 +81,13 @@ stdenv.mkDerivation {
     # Change the interpreter for various binaries
     for i in sbin/VBoxService bin/{VBoxClient,VBoxControl} other/mount.vboxsf
     do
-        ${if stdenv.system == "i686-linux" then ''
+        ${if stdenv.hostPlatform.system == "i686-linux" then ''
           patchelf --set-interpreter ${stdenv.glibc.out}/lib/ld-linux.so.2 $i
         ''
-        else if stdenv.system == "x86_64-linux" then ''
+        else if stdenv.hostPlatform.system == "x86_64-linux" then ''
           patchelf --set-interpreter ${stdenv.glibc.out}/lib/ld-linux-x86-64.so.2 $i
         ''
-        else throw ("Architecture: "+stdenv.system+" not supported for VirtualBox guest additions")
+        else throw ("Architecture: "+stdenv.hostPlatform.system+" not supported for VirtualBox guest additions")
         }
         patchelf --set-rpath ${lib.makeLibraryPath [ stdenv.cc.cc dbus libX11 libXt libXext libXmu libXfixes libXrandr libXcursor ]} $i
     done
diff --git a/pkgs/applications/window-managers/i3/default.nix b/pkgs/applications/window-managers/i3/default.nix
index 513fe06df8f6..5c95b9daf251 100644
--- a/pkgs/applications/window-managers/i3/default.nix
+++ b/pkgs/applications/window-managers/i3/default.nix
@@ -36,9 +36,9 @@ stdenv.mkDerivation rec {
   # they shouldn't, and then even once that's fixed have some
   # perl-related errors later on. For more, see
   # https://github.com/NixOS/nixpkgs/issues/7957
-  doCheck = false; # stdenv.system == "x86_64-linux";
+  doCheck = false; # stdenv.hostPlatform.system == "x86_64-linux";
 
-  checkPhase = stdenv.lib.optionalString (stdenv.system == "x86_64-linux")
+  checkPhase = stdenv.lib.optionalString (stdenv.hostPlatform.system == "x86_64-linux")
   ''
     (cd testcases && xvfb-run ./complete-run.pl -p 1 --keep-xserver-output)
     ! grep -q '^not ok' testcases/latest/complete-run.log