nixos: add preferLocalBuild=true; on derivations for config files

56 files changed, 99 insertions, 60 deletions

diff --git a/nixos/modules/config/fonts/fontconfig-penultimate.nix b/nixos/modules/config/fonts/fontconfig-penultimate.nix
index 7e05e77d967..2c18244621a 100644
--- a/nixos/modules/config/fonts/fontconfig-penultimate.nix
+++ b/nixos/modules/config/fonts/fontconfig-penultimate.nix
@@ -55,7 +55,9 @@ let
   localConf = pkgs.writeText "fc-local.conf" cfg.localConf;
 
   # The configuration to be included in /etc/font/
-  penultimateConf = pkgs.runCommand "font-penultimate-conf" {} ''
+  penultimateConf = pkgs.runCommand "font-penultimate-conf" {
+    preferLocalBuild = true;
+    } ''
     support_folder=$out/etc/fonts/conf.d
     latest_folder=$out/etc/fonts/${latestVersion}/conf.d
 
diff --git a/nixos/modules/config/fonts/fontconfig-ultimate.nix b/nixos/modules/config/fonts/fontconfig-ultimate.nix
index 7549dc6c065..45328f3eaf1 100644
--- a/nixos/modules/config/fonts/fontconfig-ultimate.nix
+++ b/nixos/modules/config/fonts/fontconfig-ultimate.nix
@@ -7,7 +7,7 @@ let cfg = config.fonts.fontconfig.ultimate;
     latestVersion  = pkgs.fontconfig.configVersion;
 
     # The configuration to be included in /etc/font/
-    confPkg = pkgs.runCommand "font-ultimate-conf" {} ''
+    confPkg = pkgs.runCommand "font-ultimate-conf" { preferLocalBuild = true; } ''
       support_folder=$out/etc/fonts/conf.d
       latest_folder=$out/etc/fonts/${latestVersion}/conf.d
 
diff --git a/nixos/modules/config/fonts/fontconfig.nix b/nixos/modules/config/fonts/fontconfig.nix
index 12f5ca2e799..d79c43c0b5b 100644
--- a/nixos/modules/config/fonts/fontconfig.nix
+++ b/nixos/modules/config/fonts/fontconfig.nix
@@ -190,7 +190,7 @@ let cfg = config.fonts.fontconfig;
     '';
 
     # fontconfig configuration package
-    confPkg = pkgs.runCommand "fontconfig-conf" {} ''
+    confPkg = pkgs.runCommand "fontconfig-conf" { preferLocalBuild = true; } ''
       support_folder=$out/etc/fonts
       latest_folder=$out/etc/fonts/${latestVersion}
 
diff --git a/nixos/modules/config/fonts/fontdir.nix b/nixos/modules/config/fonts/fontdir.nix
index 180e38f81f4..cc70fbf8744 100644
--- a/nixos/modules/config/fonts/fontdir.nix
+++ b/nixos/modules/config/fonts/fontdir.nix
@@ -4,7 +4,7 @@ with lib;
 
 let
 
-  x11Fonts = pkgs.runCommand "X11-fonts" { } ''
+  x11Fonts = pkgs.runCommand "X11-fonts" { preferLocalBuild = true; } ''
     mkdir -p "$out/share/X11-fonts"
     find ${toString config.fonts.fonts} \
       \( -name fonts.dir -o -name '*.ttf' -o -name '*.otf' \) \
diff --git a/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix b/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix
index 2cf5f13bc15..a808429c999 100644
--- a/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix
+++ b/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix
@@ -29,6 +29,7 @@ runCommand "uvcdynctrl-udev-rules-${version}"
   ];
   dontPatchELF = true;
   dontStrip = true;
+  preferLocalBuild = true;
 }
 ''
   mkdir -p "$out/lib/udev"
diff --git a/nixos/modules/installer/cd-dvd/channel.nix b/nixos/modules/installer/cd-dvd/channel.nix
index e946c4abc57..ab5e7c0645f 100644
--- a/nixos/modules/installer/cd-dvd/channel.nix
+++ b/nixos/modules/installer/cd-dvd/channel.nix
@@ -13,7 +13,7 @@ let
   # user, as expected by nixos-rebuild/nixos-install. FIXME: merge
   # with make-channel.nix.
   channelSources = pkgs.runCommand "nixos-${config.system.nixos.version}"
-    { }
+    { preferLocalBuild = true; }
     ''
       mkdir -p $out
       cp -prd ${nixpkgs.outPath} $out/nixos
diff --git a/nixos/modules/programs/less.nix b/nixos/modules/programs/less.nix
index d39103a5805..9fdf99e9c69 100644
--- a/nixos/modules/programs/less.nix
+++ b/nixos/modules/programs/less.nix
@@ -25,7 +25,7 @@ let
   '';
 
   lessKey = pkgs.runCommand "lesskey"
-            { src = pkgs.writeText "lessconfig" configText; }
+            { src = pkgs.writeText "lessconfig" configText; preferLocalBuild = true; }
             "${pkgs.less}/bin/lesskey -o $out $src";
 
 in
diff --git a/nixos/modules/security/ca.nix b/nixos/modules/security/ca.nix
index 67469be18b4..1c4ee421fc5 100644
--- a/nixos/modules/security/ca.nix
+++ b/nixos/modules/security/ca.nix
@@ -14,6 +14,7 @@ let
     { files =
         cfg.certificateFiles ++
         [ (builtins.toFile "extra.crt" (concatStringsSep "\n" cfg.certificates)) ];
+      preferLocalBuild = true;
      }
     ''
       cat $files > $out
diff --git a/nixos/modules/security/sudo.nix b/nixos/modules/security/sudo.nix
index 69a2a4f8f9a..573588aaeec 100644
--- a/nixos/modules/security/sudo.nix
+++ b/nixos/modules/security/sudo.nix
@@ -215,7 +215,10 @@ in
     environment.etc = singleton
       { source =
           pkgs.runCommand "sudoers"
-          { src = pkgs.writeText "sudoers-in" cfg.configFile; }
+          {
+            src = pkgs.writeText "sudoers-in" cfg.configFile;
+            preferLocalBuild = true;
+          }
           # Make sure that the sudoers file is syntactically valid.
           # (currently disabled - NIXOS-66)
           "${pkgs.buildPackages.sudo}/sbin/visudo -f $src -c && cp $src $out";
diff --git a/nixos/modules/services/continuous-integration/buildkite-agent.nix b/nixos/modules/services/continuous-integration/buildkite-agent.nix
index 9daf391c73c..2136778aff4 100644
--- a/nixos/modules/services/continuous-integration/buildkite-agent.nix
+++ b/nixos/modules/services/continuous-integration/buildkite-agent.nix
@@ -24,7 +24,7 @@ let
       EOF
       chmod 755 $out/${name}
     '';
-  in pkgs.runCommand "buildkite-agent-hooks" {} ''
+  in pkgs.runCommand "buildkite-agent-hooks" { preferLocalBuild = true; } ''
     mkdir $out
     ${concatStringsSep "\n" (mapAttrsToList mkHookEntry (filterAttrs (n: v: v != null) cfg.hooks))}
   '';
diff --git a/nixos/modules/services/continuous-integration/gitlab-runner.nix b/nixos/modules/services/continuous-integration/gitlab-runner.nix
index a0aff1b8b5b..3ceaa6f5ff3 100644
--- a/nixos/modules/services/continuous-integration/gitlab-runner.nix
+++ b/nixos/modules/services/continuous-integration/gitlab-runner.nix
@@ -8,6 +8,7 @@ let
     if (cfg.configFile == null) then
       (pkgs.runCommand "config.toml" {
         buildInputs = [ pkgs.remarshal ];
+        preferLocalBuild = true;
       } ''
         remarshal -if json -of toml \
           < ${pkgs.writeText "config.json" (builtins.toJSON cfg.configOptions)} \
diff --git a/nixos/modules/services/databases/hbase.nix b/nixos/modules/services/databases/hbase.nix
index 4772e897efe..52f2d95b4e0 100644
--- a/nixos/modules/services/databases/hbase.nix
+++ b/nixos/modules/services/databases/hbase.nix
@@ -18,7 +18,7 @@ let
     </configuration>
   '';
 
-  configDir = pkgs.runCommand "hbase-config-dir" {} ''
+  configDir = pkgs.runCommand "hbase-config-dir" { preferLocalBuild = true; } ''
     mkdir -p $out
     cp ${cfg.package}/conf/* $out/
     rm $out/hbase-site.xml
diff --git a/nixos/modules/services/databases/influxdb.nix b/nixos/modules/services/databases/influxdb.nix
index d7a028b25d8..888bf13c3df 100644
--- a/nixos/modules/services/databases/influxdb.nix
+++ b/nixos/modules/services/databases/influxdb.nix
@@ -98,6 +98,7 @@ let
 
   configFile = pkgs.runCommand "config.toml" {
     buildInputs = [ pkgs.remarshal ];
+    preferLocalBuild = true;
   } ''
     remarshal -if json -of toml \
       < ${pkgs.writeText "config.json" (builtins.toJSON configOptions)} \
diff --git a/nixos/modules/services/hardware/acpid.nix b/nixos/modules/services/hardware/acpid.nix
index 0f05876aee3..4c97485d972 100644
--- a/nixos/modules/services/hardware/acpid.nix
+++ b/nixos/modules/services/hardware/acpid.nix
@@ -21,7 +21,7 @@ let
     };
   };
 
-  acpiConfDir = pkgs.runCommand "acpi-events" {}
+  acpiConfDir = pkgs.runCommand "acpi-events" { preferLocalBuild = true; }
     ''
       mkdir -p $out
       ${
diff --git a/nixos/modules/services/hardware/tlp.nix b/nixos/modules/services/hardware/tlp.nix
index b894025c0fd..092ff051a04 100644
--- a/nixos/modules/services/hardware/tlp.nix
+++ b/nixos/modules/services/hardware/tlp.nix
@@ -17,6 +17,7 @@ tlp = pkgs.tlp.override {
 confFile = pkgs.runCommand "tlp"
   { config = cfg.extraConfig;
     passAsFile = [ "config" ];
+    preferLocalBuild = true;
   }
   ''
     cat ${tlp}/etc/default/tlp > $out
diff --git a/nixos/modules/services/logging/logcheck.nix b/nixos/modules/services/logging/logcheck.nix
index 1477d273d5e..9c64160e92b 100644
--- a/nixos/modules/services/logging/logcheck.nix
+++ b/nixos/modules/services/logging/logcheck.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.services.logcheck;
 
-  defaultRules = pkgs.runCommand "logcheck-default-rules" {} ''
+  defaultRules = pkgs.runCommand "logcheck-default-rules" { preferLocalBuild = true; } ''
                    cp -prd ${pkgs.logcheck}/etc/logcheck $out
                    chmod u+w $out
                    rm -r $out/logcheck.*
diff --git a/nixos/modules/services/logging/logstash.nix b/nixos/modules/services/logging/logstash.nix
index aa019d855ea..9b707e9deb5 100644
--- a/nixos/modules/services/logging/logstash.nix
+++ b/nixos/modules/services/logging/logstash.nix
@@ -27,7 +27,10 @@ let
 
   logstashSettingsYml = pkgs.writeText "logstash.yml" cfg.extraSettings;
 
-  logstashSettingsDir = pkgs.runCommand "logstash-settings" {inherit logstashSettingsYml;} ''
+  logstashSettingsDir = pkgs.runCommand "logstash-settings" {
+      inherit logstashSettingsYml;
+      preferLocalBuild = true;
+    } ''
     mkdir -p $out
     ln -s $logstashSettingsYml $out/logstash.yml
   '';
diff --git a/nixos/modules/services/mail/opensmtpd.nix b/nixos/modules/services/mail/opensmtpd.nix
index 4276552d4f0..a870550ba50 100644
--- a/nixos/modules/services/mail/opensmtpd.nix
+++ b/nixos/modules/services/mail/opensmtpd.nix
@@ -8,7 +8,7 @@ let
   conf = pkgs.writeText "smtpd.conf" cfg.serverConfiguration;
   args = concatStringsSep " " cfg.extraServerArgs;
 
-  sendmail = pkgs.runCommand "opensmtpd-sendmail" {} ''
+  sendmail = pkgs.runCommand "opensmtpd-sendmail" { preferLocalBuild = true; } ''
     mkdir -p $out/bin
     ln -s ${cfg.package}/sbin/smtpctl $out/bin/sendmail
   '';
diff --git a/nixos/modules/services/misc/gitolite.nix b/nixos/modules/services/misc/gitolite.nix
index b9c2a966e6f..c7f2a168f8a 100644
--- a/nixos/modules/services/misc/gitolite.nix
+++ b/nixos/modules/services/misc/gitolite.nix
@@ -110,7 +110,7 @@ in
   config = mkIf cfg.enable (
   let
     manageGitoliteRc = cfg.extraGitoliteRc != "";
-    rcDir = pkgs.runCommand "gitolite-rc" { } rcDirScript;
+    rcDir = pkgs.runCommand "gitolite-rc" { preferLocalBuild = true; } rcDirScript;
     rcDirScript =
       ''
         mkdir "$out"
diff --git a/nixos/modules/services/misc/nix-daemon.nix b/nixos/modules/services/misc/nix-daemon.nix
index 9a8116a03e8..665215822af 100644
--- a/nixos/modules/services/misc/nix-daemon.nix
+++ b/nixos/modules/services/misc/nix-daemon.nix
@@ -33,7 +33,7 @@ let
       sh = pkgs.runtimeShell;
       binshDeps = pkgs.writeReferencesToFile sh;
     in
-      pkgs.runCommand "nix.conf" { extraOptions = cfg.extraOptions; } (''
+      pkgs.runCommand "nix.conf" { preferLocalBuild = true; extraOptions = cfg.extraOptions; } (''
         ${optionalString (!isNix20) ''
           extraPaths=$(for i in $(cat ${binshDeps}); do if test -d $i; then echo $i; fi; done)
         ''}
diff --git a/nixos/modules/services/misc/taskserver/default.nix b/nixos/modules/services/misc/taskserver/default.nix
index 5f97abf1871..483bc99ad94 100644
--- a/nixos/modules/services/misc/taskserver/default.nix
+++ b/nixos/modules/services/misc/taskserver/default.nix
@@ -109,7 +109,7 @@ let
   nixos-taskserver = pkgs.pythonPackages.buildPythonApplication {
     name = "nixos-taskserver";
 
-    src = pkgs.runCommand "nixos-taskserver-src" {} ''
+    src = pkgs.runCommand "nixos-taskserver-src" { preferLocalBuild = true; } ''
       mkdir -p "$out"
       cat "${pkgs.substituteAll {
         src = ./helper-tool.py;
diff --git a/nixos/modules/services/monitoring/apcupsd.nix b/nixos/modules/services/monitoring/apcupsd.nix
index 7ee870183ca..49957e65290 100644
--- a/nixos/modules/services/monitoring/apcupsd.nix
+++ b/nixos/modules/services/monitoring/apcupsd.nix
@@ -45,7 +45,7 @@ let
 
   eventToShellCmds = event: if builtins.hasAttr event cfg.hooks then (shellCmdsForEventScript event (builtins.getAttr event cfg.hooks)) else "";
 
-  scriptDir = pkgs.runCommand "apcupsd-scriptdir" {} (''
+  scriptDir = pkgs.runCommand "apcupsd-scriptdir" { preferLocalBuild = true; } (''
     mkdir "$out"
     # Copy SCRIPTDIR from apcupsd package
     cp -r ${pkgs.apcupsd}/etc/apcupsd/* "$out"/
diff --git a/nixos/modules/services/monitoring/graphite.nix b/nixos/modules/services/monitoring/graphite.nix
index cdc98b407e9..f59bc56962b 100644
--- a/nixos/modules/services/monitoring/graphite.nix
+++ b/nixos/modules/services/monitoring/graphite.nix
@@ -9,8 +9,10 @@ let
   dataDir = cfg.dataDir;
   staticDir = cfg.dataDir + "/static";
 
-  graphiteLocalSettingsDir = pkgs.runCommand "graphite_local_settings"
-    {inherit graphiteLocalSettings;} ''
+  graphiteLocalSettingsDir = pkgs.runCommand "graphite_local_settings" {
+      inherit graphiteLocalSettings;
+      preferLocalBuild = true; 
+    } ''
     mkdir -p $out
     ln -s $graphiteLocalSettings $out/graphite_local_settings.py
   '';
diff --git a/nixos/modules/services/monitoring/nagios.nix b/nixos/modules/services/monitoring/nagios.nix
index 3e1d727b416..e5496209f82 100644
--- a/nixos/modules/services/monitoring/nagios.nix
+++ b/nixos/modules/services/monitoring/nagios.nix
@@ -11,8 +11,10 @@ let
 
   nagiosObjectDefs = cfg.objectDefs;
 
-  nagiosObjectDefsDir = pkgs.runCommand "nagios-objects" {inherit nagiosObjectDefs;}
-    "mkdir -p $out; ln -s $nagiosObjectDefs $out/";
+  nagiosObjectDefsDir = pkgs.runCommand "nagios-objects" {
+      inherit nagiosObjectDefs;
+      preferLocalBuild = true;
+    } "mkdir -p $out; ln -s $nagiosObjectDefs $out/";
 
   nagiosCfgFile = pkgs.writeText "nagios.cfg"
     ''
diff --git a/nixos/modules/services/monitoring/netdata.nix b/nixos/modules/services/monitoring/netdata.nix
index 1d86c5d893d..a49555cf677 100644
--- a/nixos/modules/services/monitoring/netdata.nix
+++ b/nixos/modules/services/monitoring/netdata.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.services.netdata;
 
-  wrappedPlugins = pkgs.runCommand "wrapped-plugins" {} ''
+  wrappedPlugins = pkgs.runCommand "wrapped-plugins" { preferLocalBuild = true; } ''
     mkdir -p $out/libexec/netdata/plugins.d
     ln -s /run/wrappers/bin/apps.plugin $out/libexec/netdata/plugins.d/apps.plugin
   '';
diff --git a/nixos/modules/services/monitoring/prometheus/default.nix b/nixos/modules/services/monitoring/prometheus/default.nix
index 1b1503ab5fc..cc703573d8c 100644
--- a/nixos/modules/services/monitoring/prometheus/default.nix
+++ b/nixos/modules/services/monitoring/prometheus/default.nix
@@ -19,7 +19,7 @@ let
 
   # Pretty-print JSON to a file
   writePrettyJSON = name: x:
-    pkgs.runCommand name { } ''
+    pkgs.runCommand name { preferLocalBuild = true; } ''
       echo '${builtins.toJSON x}' | ${pkgs.jq}/bin/jq . > $out
     '';
 
diff --git a/nixos/modules/services/monitoring/scollector.nix b/nixos/modules/services/monitoring/scollector.nix
index 6ecb21d628d..fbded746a5f 100644
--- a/nixos/modules/services/monitoring/scollector.nix
+++ b/nixos/modules/services/monitoring/scollector.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.services.scollector;
 
-  collectors = pkgs.runCommand "collectors" {}
+  collectors = pkgs.runCommand "collectors" { preferLocalBuild = true; }
     ''
     mkdir -p $out
     ${lib.concatStringsSep
diff --git a/nixos/modules/services/monitoring/telegraf.nix b/nixos/modules/services/monitoring/telegraf.nix
index 6bfcd7143e1..d8786732668 100644
--- a/nixos/modules/services/monitoring/telegraf.nix
+++ b/nixos/modules/services/monitoring/telegraf.nix
@@ -7,6 +7,7 @@ let
 
   configFile = pkgs.runCommand "config.toml" {
     buildInputs = [ pkgs.remarshal ];
+    preferLocalBuild = true;
   } ''
     remarshal -if json -of toml \
       < ${pkgs.writeText "config.json" (builtins.toJSON cfg.extraConfig)} \
diff --git a/nixos/modules/services/monitoring/uptime.nix b/nixos/modules/services/monitoring/uptime.nix
index b4d3a264010..c0993f3bc2e 100644
--- a/nixos/modules/services/monitoring/uptime.nix
+++ b/nixos/modules/services/monitoring/uptime.nix
@@ -4,7 +4,8 @@ let
 
   cfg = config.services.uptime;
 
-  configDir = pkgs.runCommand "config" {} (if cfg.configFile != null then ''
+  configDir = pkgs.runCommand "config" { preferLocalBuild = true; }
+  (if cfg.configFile != null then ''
     mkdir $out
     ext=`echo ${cfg.configFile} | grep -o \\..*`
     ln -sv ${cfg.configFile} $out/default$ext
diff --git a/nixos/modules/services/network-filesystems/beegfs.nix b/nixos/modules/services/network-filesystems/beegfs.nix
index d9dde3f6bb6..86b1bb9160f 100644
--- a/nixos/modules/services/network-filesystems/beegfs.nix
+++ b/nixos/modules/services/network-filesystems/beegfs.nix
@@ -102,7 +102,10 @@ let
 
   # wrappers to beegfs tools. Avoid typing path of config files
   utilWrappers = mapAttrsToList ( name: cfg:
-      ( pkgs.runCommand "beegfs-utils-${name}" { nativeBuildInputs = [ pkgs.makeWrapper ]; } ''
+    ( pkgs.runCommand "beegfs-utils-${name}" {
+        nativeBuildInputs = [ pkgs.makeWrapper ];
+        preferLocalBuild = true;
+        } ''
         mkdir -p $out/bin
 
         makeWrapper ${pkgs.beegfs}/bin/beegfs-check-servers \
diff --git a/nixos/modules/services/network-filesystems/ipfs.nix b/nixos/modules/services/network-filesystems/ipfs.nix
index 602cd50d8f5..d4fa1eccdf3 100644
--- a/nixos/modules/services/network-filesystems/ipfs.nix
+++ b/nixos/modules/services/network-filesystems/ipfs.nix
@@ -19,7 +19,7 @@ let
     "/var/lib/ipfs/.ipfs";
 
   # Wrapping the ipfs binary with the environment variable IPFS_PATH set to dataDir because we can't set it in the user environment
-  wrapped = runCommand "ipfs" { buildInputs = [ makeWrapper ]; } ''
+  wrapped = runCommand "ipfs" { buildInputs = [ makeWrapper ]; preferLocalBuild = true; } ''
     mkdir -p "$out/bin"
     makeWrapper "${ipfs}/bin/ipfs" "$out/bin/ipfs" \
       --set IPFS_PATH ${cfg.dataDir} \
diff --git a/nixos/modules/services/network-filesystems/openafs/client.nix b/nixos/modules/services/network-filesystems/openafs/client.nix
index 240c1392088..93d2d7fcd97 100644
--- a/nixos/modules/services/network-filesystems/openafs/client.nix
+++ b/nixos/modules/services/network-filesystems/openafs/client.nix
@@ -15,7 +15,7 @@ let
 
   clientServDB = pkgs.writeText "client-cellServDB-${cfg.cellName}" (mkCellServDB cfg.cellName cfg.cellServDB);
 
-  afsConfig = pkgs.runCommand "afsconfig" {} ''
+  afsConfig = pkgs.runCommand "afsconfig" { preferLocalBuild = true; } ''
     mkdir -p $out
     echo ${cfg.cellName} > $out/ThisCell
     cat ${cellServDB} ${clientServDB} > $out/CellServDB
@@ -198,7 +198,7 @@ in
 
     environment.etc = {
       clientCellServDB = {
-        source = pkgs.runCommand "CellServDB" {} ''
+        source = pkgs.runCommand "CellServDB" { preferLocalBuild = true; } ''
           cat ${cellServDB} ${clientServDB} > $out
         '';
         target = "openafs/CellServDB";
diff --git a/nixos/modules/services/networking/dnscache.nix b/nixos/modules/services/networking/dnscache.nix
index fc30f50317f..5051fc916d9 100644
--- a/nixos/modules/services/networking/dnscache.nix
+++ b/nixos/modules/services/networking/dnscache.nix
@@ -5,7 +5,7 @@ with lib;
 let
   cfg = config.services.dnscache;
 
-  dnscache-root = pkgs.runCommand "dnscache-root" {} ''
+  dnscache-root = pkgs.runCommand "dnscache-root" { preferLocalBuild = true; } ''
     mkdir -p $out/{servers,ip}
 
     ${concatMapStrings (ip: ''
diff --git a/nixos/modules/services/networking/hylafax/systemd.nix b/nixos/modules/services/networking/hylafax/systemd.nix
index 91d9c1a37da..ef177e4be34 100644
--- a/nixos/modules/services/networking/hylafax/systemd.nix
+++ b/nixos/modules/services/networking/hylafax/systemd.nix
@@ -41,7 +41,7 @@ let
           "$out/config.${name}"
       '';
     in
-      pkgs.runCommand "hylafax-config-modems" {}
+      pkgs.runCommand "hylafax-config-modems" { preferLocalBuild = true; }
       ''mkdir --parents "$out/" ${concatStringsSep "\n" (mapModems mkLine)}'';
 
   setupSpoolScript = pkgs.substituteAll {
diff --git a/nixos/modules/services/networking/prayer.nix b/nixos/modules/services/networking/prayer.nix
index f63f86496be..c936417e68c 100644
--- a/nixos/modules/services/networking/prayer.nix
+++ b/nixos/modules/services/networking/prayer.nix
@@ -25,7 +25,7 @@ let
     ${cfg.extraConfig}
   '';
 
-  prayerCfg = pkgs.runCommand "prayer.cf" { } ''
+  prayerCfg = pkgs.runCommand "prayer.cf" { preferLocalBuild = true; } ''
     # We have to remove the http_port 80, or it will start a server there
     cat ${prayer}/etc/prayer.cf | grep -v http_port > $out
     cat ${prayerExtraCfg} >> $out
diff --git a/nixos/modules/services/networking/shout.nix b/nixos/modules/services/networking/shout.nix
index 1ea676d0f92..f511a9af256 100644
--- a/nixos/modules/services/networking/shout.nix
+++ b/nixos/modules/services/networking/shout.nix
@@ -6,7 +6,7 @@ let
   cfg = config.services.shout;
   shoutHome = "/var/lib/shout";
 
-  defaultConfig = pkgs.runCommand "config.js" {} ''
+  defaultConfig = pkgs.runCommand "config.js" { preferLocalBuild = true; } ''
     EDITOR=true ${pkgs.shout}/bin/shout config --home $PWD
     mv config.js $out
   '';
diff --git a/nixos/modules/services/networking/xrdp.nix b/nixos/modules/services/networking/xrdp.nix
index a1c5d879f3c..cc18f6d0064 100644
--- a/nixos/modules/services/networking/xrdp.nix
+++ b/nixos/modules/services/networking/xrdp.nix
@@ -4,7 +4,7 @@ with lib;
 
 let
   cfg = config.services.xrdp;
-  confDir = pkgs.runCommand "xrdp.conf" { } ''
+  confDir = pkgs.runCommand "xrdp.conf" { preferLocalBuild = true; } ''
     mkdir $out
 
     cp ${cfg.package}/etc/xrdp/{km-*,xrdp,sesman,xrdp_keyboard}.ini $out
diff --git a/nixos/modules/services/printing/cupsd.nix b/nixos/modules/services/printing/cupsd.nix
index 3a43ebbb889..854c76cc0a1 100644
--- a/nixos/modules/services/printing/cupsd.nix
+++ b/nixos/modules/services/printing/cupsd.nix
@@ -11,8 +11,9 @@ let
   avahiEnabled = config.services.avahi.enable;
   polkitEnabled = config.security.polkit.enable;
 
-  additionalBackends = pkgs.runCommand "additional-cups-backends" { }
-    ''
+  additionalBackends = pkgs.runCommand "additional-cups-backends" {
+      preferLocalBuild = true;
+    } ''
       mkdir -p $out
       if [ ! -e ${cups.out}/lib/cups/backend/smb ]; then
         mkdir -p $out/lib/cups/backend
diff --git a/nixos/modules/services/ttys/kmscon.nix b/nixos/modules/services/ttys/kmscon.nix
index 82b6a51028e..dc37f9bee4b 100644
--- a/nixos/modules/services/ttys/kmscon.nix
+++ b/nixos/modules/services/ttys/kmscon.nix
@@ -82,7 +82,7 @@ in {
       X-RestartIfChanged=false
     '';
 
-    systemd.units."autovt@.service".unit = pkgs.runCommand "unit" { }
+    systemd.units."autovt@.service".unit = pkgs.runCommand "unit" { preferLocalBuild = true; }
         ''
           mkdir -p $out
           ln -s ${config.systemd.units."kmsconvt@.service".unit}/kmsconvt@.service $out/autovt@.service
diff --git a/nixos/modules/services/web-apps/codimd.nix b/nixos/modules/services/web-apps/codimd.nix
index a0af28eac7c..56e1de17e3c 100644
--- a/nixos/modules/services/web-apps/codimd.nix
+++ b/nixos/modules/services/web-apps/codimd.nix
@@ -6,7 +6,7 @@ let
   cfg = config.services.codimd;
 
   prettyJSON = conf:
-    pkgs.runCommand "codimd-config.json" { } ''
+    pkgs.runCommand "codimd-config.json" { preferLocalBuild = true; } ''
       echo '${builtins.toJSON conf}' | ${pkgs.jq}/bin/jq \
         '{production:del(.[]|nulls)|del(.[][]?|nulls)}' > $out
     '';
diff --git a/nixos/modules/services/web-servers/apache-httpd/default.nix b/nixos/modules/services/web-servers/apache-httpd/default.nix
index 3fd19d425c7..1eac5be2f8d 100644
--- a/nixos/modules/services/web-servers/apache-httpd/default.nix
+++ b/nixos/modules/services/web-servers/apache-httpd/default.nix
@@ -217,7 +217,7 @@ let
     ) null ([ cfg ] ++ subservices);
 
     documentRoot = if maybeDocumentRoot != null then maybeDocumentRoot else
-      pkgs.runCommand "empty" {} "mkdir -p $out";
+      pkgs.runCommand "empty" { preferLocalBuild = true; } "mkdir -p $out";
 
     documentRootConf = ''
       DocumentRoot "${documentRoot}"
@@ -426,6 +426,7 @@ let
   phpIni = pkgs.runCommand "php.ini"
     { options = concatStringsSep "\n"
         ([ mainCfg.phpOptions ] ++ (map (svc: svc.phpOptions) allSubservices));
+      preferLocalBuild = true;
     }
     ''
       cat ${php}/etc/php.ini > $out
diff --git a/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix b/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix
index e871ae6ff15..6234478014c 100644
--- a/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix
+++ b/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix
@@ -116,9 +116,10 @@ let
       '';
   };
 
-  mediawikiScripts = pkgs.runCommand "mediawiki-${config.id}-scripts"
-    { buildInputs = [ pkgs.makeWrapper ]; }
-    ''
+  mediawikiScripts = pkgs.runCommand "mediawiki-${config.id}-scripts" {
+      buildInputs = [ pkgs.makeWrapper ];
+      preferLocalBuild = true;
+    } ''
       mkdir -p $out/bin
       for i in changePassword.php createAndPromote.php userOptions.php edit.php nukePage.php update.php; do
         makeWrapper ${php}/bin/php $out/bin/mediawiki-${config.id}-$(basename $i .php) \
diff --git a/nixos/modules/services/web-servers/phpfpm/default.nix b/nixos/modules/services/web-servers/phpfpm/default.nix
index 97c730061bd..ffafbc5e92f 100644
--- a/nixos/modules/services/web-servers/phpfpm/default.nix
+++ b/nixos/modules/services/web-servers/phpfpm/default.nix
@@ -39,6 +39,7 @@ let
 
   phpIni = pool: pkgs.runCommand "php.ini" {
     inherit (pool) phpPackage phpOptions;
+    preferLocalBuild = true;
     nixDefaults = ''
       sendmail_path = "/run/wrappers/bin/sendmail -t -i"
     '';
diff --git a/nixos/modules/services/web-servers/traefik.nix b/nixos/modules/services/web-servers/traefik.nix
index 700202b1d28..4674ed0177e 100644
--- a/nixos/modules/services/web-servers/traefik.nix
+++ b/nixos/modules/services/web-servers/traefik.nix
@@ -8,6 +8,7 @@ let
     if cfg.configFile == null then
       pkgs.runCommand "config.toml" {
         buildInputs = [ pkgs.remarshal ];
+        preferLocalBuild = true;
       } ''
         remarshal -if json -of toml \
           < ${pkgs.writeText "config.json" (builtins.toJSON cfg.configOptions)} \
diff --git a/nixos/modules/services/x11/desktop-managers/gnome3.nix b/nixos/modules/services/x11/desktop-managers/gnome3.nix
index 31ff60019ae..6255dce8276 100644
--- a/nixos/modules/services/x11/desktop-managers/gnome3.nix
+++ b/nixos/modules/services/x11/desktop-managers/gnome3.nix
@@ -15,7 +15,7 @@ let
     '';
   };
 
-  nixos-gsettings-desktop-schemas = pkgs.runCommand "nixos-gsettings-desktop-schemas" {}
+  nixos-gsettings-desktop-schemas = pkgs.runCommand "nixos-gsettings-desktop-schemas" { preferLocalBuild = true; }
     ''
      mkdir -p $out/share/gsettings-schemas/nixos-gsettings-overrides/glib-2.0/schemas
      cp -rf ${pkgs.gnome3.gsettings-desktop-schemas}/share/gsettings-schemas/gsettings-desktop-schemas*/glib-2.0/schemas/*.xml $out/share/gsettings-schemas/nixos-gsettings-overrides/glib-2.0/schemas
diff --git a/nixos/modules/services/x11/display-managers/lightdm-greeters/enso-os.nix b/nixos/modules/services/x11/display-managers/lightdm-greeters/enso-os.nix
index 7c794b1ba17..de128809ce3 100644
--- a/nixos/modules/services/x11/display-managers/lightdm-greeters/enso-os.nix
+++ b/nixos/modules/services/x11/display-managers/lightdm-greeters/enso-os.nix
@@ -12,9 +12,10 @@ let
 
   # We need a few things in the environment for the greeter to run with
   # fonts/icons.
-  wrappedEnsoGreeter = pkgs.runCommand "lightdm-enso-os-greeter"
-    { buildInputs = [ pkgs.makeWrapper ]; }
-    ''
+  wrappedEnsoGreeter = pkgs.runCommand "lightdm-enso-os-greeter" {
+      buildInputs = [ pkgs.makeWrapper ];
+      preferLocalBuild = true;
+    } ''
       # This wrapper ensures that we actually get themes
       makeWrapper ${pkgs.lightdm-enso-os-greeter}/bin/pantheon-greeter \
         $out/greeter \
diff --git a/nixos/modules/services/x11/display-managers/lightdm-greeters/gtk.nix b/nixos/modules/services/x11/display-managers/lightdm-greeters/gtk.nix
index efec943c007..772cc95e84e 100644
--- a/nixos/modules/services/x11/display-managers/lightdm-greeters/gtk.nix
+++ b/nixos/modules/services/x11/display-managers/lightdm-greeters/gtk.nix
@@ -18,9 +18,10 @@ let
   # The default greeter provided with this expression is the GTK greeter.
   # Again, we need a few things in the environment for the greeter to run with
   # fonts/icons.
-  wrappedGtkGreeter = pkgs.runCommand "lightdm-gtk-greeter"
-    { buildInputs = [ pkgs.makeWrapper ]; }
-    ''
+  wrappedGtkGreeter = pkgs.runCommand "lightdm-gtk-greeter" {
+      buildInputs = [ pkgs.makeWrapper ];
+      preferLocalBuild = true;
+    } ''
       # This wrapper ensures that we actually get themes
       makeWrapper ${pkgs.lightdm_gtk_greeter}/sbin/lightdm-gtk-greeter \
         $out/greeter \
diff --git a/nixos/modules/services/x11/display-managers/slim.nix b/nixos/modules/services/x11/display-managers/slim.nix
index 4e411c8ceb0..124660a43f0 100644
--- a/nixos/modules/services/x11/display-managers/slim.nix
+++ b/nixos/modules/services/x11/display-managers/slim.nix
@@ -28,7 +28,7 @@ let
   # Unpack the SLiM theme, or use the default.
   slimThemesDir =
     let
-      unpackedTheme = pkgs.runCommand "slim-theme" {}
+      unpackedTheme = pkgs.runCommand "slim-theme" { preferLocalBuild = true; }
         ''
           mkdir -p $out
           cd $out
diff --git a/nixos/modules/services/x11/gdk-pixbuf.nix b/nixos/modules/services/x11/gdk-pixbuf.nix
index 58faa8e2f9d..2dc8eabd95a 100644
--- a/nixos/modules/services/x11/gdk-pixbuf.nix
+++ b/nixos/modules/services/x11/gdk-pixbuf.nix
@@ -10,7 +10,7 @@ let
 
   # Generate the cache file by running gdk-pixbuf-query-loaders for each
   # package and concatenating the results.
-  loadersCache = pkgs.runCommand "gdk-pixbuf-loaders.cache" {} ''
+  loadersCache = pkgs.runCommand "gdk-pixbuf-loaders.cache" { preferLocalBuild = true; } ''
     (
       for package in ${concatStringsSep " " effectivePackages}; do
         module_dir="$package/${pkgs.gdk_pixbuf.moduleDir}"
diff --git a/nixos/modules/services/x11/xserver.nix b/nixos/modules/services/x11/xserver.nix
index 34ae8c11a3f..06e09d0d51c 100644
--- a/nixos/modules/services/x11/xserver.nix
+++ b/nixos/modules/services/x11/xserver.nix
@@ -113,6 +113,7 @@ let
     { xfs = optionalString (cfg.useXFS != false)
         ''FontPath "${toString cfg.useXFS}"'';
       inherit (cfg) config;
+      preferLocalBuild = true;
     }
       ''
         echo 'Section "Files"' >> $out
@@ -705,6 +706,7 @@ in
     system.extraDependencies = singleton (pkgs.runCommand "xkb-validated" {
       inherit (cfg) xkbModel layout xkbVariant xkbOptions;
       nativeBuildInputs = [ pkgs.xkbvalidate ];
+      preferLocalBuild = true;
     } ''
       validate "$xkbModel" "$layout" "$xkbVariant" "$xkbOptions"
       touch "$out"
diff --git a/nixos/modules/system/boot/stage-1.nix b/nixos/modules/system/boot/stage-1.nix
index 5e27b24ac44..9984a97bbdd 100644
--- a/nixos/modules/system/boot/stage-1.nix
+++ b/nixos/modules/system/boot/stage-1.nix
@@ -196,9 +196,10 @@ let
     ''; # */
 
 
-  udevRules = pkgs.runCommand "udev-rules"
-    { allowedReferences = [ extraUtils ]; }
-    ''
+  udevRules = pkgs.runCommand "udev-rules" {
+      allowedReferences = [ extraUtils ];
+      preferLocalBuild = true;
+    } ''
       mkdir -p $out
 
       echo 'ENV{LD_LIBRARY_PATH}="${extraUtils}/lib"' > $out/00-env.rules
@@ -298,9 +299,10 @@ let
         { object = pkgs.writeText "mdadm.conf" config.boot.initrd.mdadmConf;
           symlink = "/etc/mdadm.conf";
         }
-        { object = pkgs.runCommand "initrd-kmod-blacklist-ubuntu"
-            { src = "${pkgs.kmod-blacklist-ubuntu}/modprobe.conf"; }
-            ''
+        { object = pkgs.runCommand "initrd-kmod-blacklist-ubuntu" {
+              src = "${pkgs.kmod-blacklist-ubuntu}/modprobe.conf";
+              preferLocalBuild = true;
+            } ''
               target=$out
               ${pkgs.buildPackages.perl}/bin/perl -0pe 's/## file: iwlwifi.conf(.+?)##/##/s;' $src > $out
             '';
diff --git a/nixos/modules/system/boot/systemd.nix b/nixos/modules/system/boot/systemd.nix
index 9fdef0251d7..bf1b1b417b1 100644
--- a/nixos/modules/system/boot/systemd.nix
+++ b/nixos/modules/system/boot/systemd.nix
@@ -759,7 +759,10 @@ in
     environment.etc = let
       # generate contents for /etc/systemd/system-generators from
       # systemd.generators and systemd.generator-packages
-      generators = pkgs.runCommand "system-generators" { packages = cfg.generator-packages; } ''
+      generators = pkgs.runCommand "system-generators" {
+          preferLocalBuild = true;
+          packages = cfg.generator-packages;
+        } ''
         mkdir -p $out
         for package in $packages
         do
diff --git a/nixos/modules/tasks/filesystems/vboxsf.nix b/nixos/modules/tasks/filesystems/vboxsf.nix
index 87f1984f084..5497194f6a8 100644
--- a/nixos/modules/tasks/filesystems/vboxsf.nix
+++ b/nixos/modules/tasks/filesystems/vboxsf.nix
@@ -6,7 +6,7 @@ let
 
   inInitrd = any (fs: fs == "vboxsf") config.boot.initrd.supportedFilesystems;
 
-  package = pkgs.runCommand "mount.vboxsf" {} ''
+  package = pkgs.runCommand "mount.vboxsf" { preferLocalBuild = true; } ''
     mkdir -p $out/bin
     cp ${pkgs.linuxPackages.virtualboxGuestAdditions}/bin/mount.vboxsf $out/bin
   '';
diff --git a/nixos/modules/tasks/kbd.nix b/nixos/modules/tasks/kbd.nix
index fbe42b8e8f0..6d34f897d18 100644
--- a/nixos/modules/tasks/kbd.nix
+++ b/nixos/modules/tasks/kbd.nix
@@ -15,6 +15,7 @@ let
   optimizedKeymap = pkgs.runCommand "keymap" {
     nativeBuildInputs = [ pkgs.buildPackages.kbd ];
     LOADKEYS_KEYMAP_PATH = "${kbdEnv}/share/keymaps/**";
+    preferLocalBuild = true;
   } ''
     loadkeys -b ${optionalString isUnicode "-u"} "${config.i18n.consoleKeyMap}" > $out
   '';
diff --git a/nixos/modules/tasks/network-interfaces.nix b/nixos/modules/tasks/network-interfaces.nix
index 815523093dd..f9b0eb330bf 100644
--- a/nixos/modules/tasks/network-interfaces.nix
+++ b/nixos/modules/tasks/network-interfaces.nix
@@ -995,7 +995,7 @@ in
       '';
 
     environment.etc."hostid" = mkIf (cfg.hostId != null)
-      { source = pkgs.runCommand "gen-hostid" {} ''
+      { source = pkgs.runCommand "gen-hostid" { preferLocalBuild = true; } ''
           hi="${cfg.hostId}"
           ${if pkgs.stdenv.isBigEndian then ''
             echo -ne "\x''${hi:0:2}\x''${hi:2:2}\x''${hi:4:2}\x''${hi:6:2}" > $out
diff --git a/pkgs/build-support/closure-info.nix b/pkgs/build-support/closure-info.nix
index 28f2802a5bc..24795a724ec 100644
--- a/pkgs/build-support/closure-info.nix
+++ b/pkgs/build-support/closure-info.nix
@@ -17,6 +17,8 @@ stdenv.mkDerivation {
 
   exportReferencesGraph.closure = rootPaths;
 
+  preferLocalBuild = true;
+
   PATH = "${buildPackages.coreutils}/bin:${buildPackages.jq}/bin";
 
   builder = builtins.toFile "builder"