diff --git a/pkgs/applications/version-management/git-and-tools/git/default.nix b/pkgs/applications/version-management/git-and-tools/git/default.nix
index b7d34906c4a8..3cdf200d581b 100644
--- a/pkgs/applications/version-management/git-and-tools/git/default.nix
+++ b/pkgs/applications/version-management/git-and-tools/git/default.nix
@@ -116,6 +116,8 @@ stdenv.mkDerivation rec {
 
      '';
 
+  enableParallelBuilding = true;
+
   meta = {
     license = "GPLv2";
     homepage = http://git-scm.com/;
diff --git a/pkgs/development/compilers/gcc-4.3/default.nix b/pkgs/development/compilers/gcc-4.3/default.nix
index 73caa156bd01..b9d0d9bff5df 100644
--- a/pkgs/development/compilers/gcc-4.3/default.nix
+++ b/pkgs/development/compilers/gcc-4.3/default.nix
@@ -127,6 +127,8 @@ stdenv.mkDerivation ({
   passthru = { inherit langC langCC langFortran langVhdl langTreelang
       enableMultilib; };
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = "http://gcc.gnu.org/";
     license = "GPL/LGPL";
diff --git a/pkgs/development/compilers/gcc-4.4/default.nix b/pkgs/development/compilers/gcc-4.4/default.nix
index e46ceaa0250f..bc9c2c89e1db 100644
--- a/pkgs/development/compilers/gcc-4.4/default.nix
+++ b/pkgs/development/compilers/gcc-4.4/default.nix
@@ -247,6 +247,8 @@ stdenv.mkDerivation ({
   passthru = { inherit langC langCC langAda langFortran langTreelang langVhdl
       enableMultilib version; };
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://gcc.gnu.org/;
     license = "GPLv3+";  # runtime support libraries are typically LGPLv3+
diff --git a/pkgs/development/compilers/gcc-4.5/default.nix b/pkgs/development/compilers/gcc-4.5/default.nix
index 0544458dfc0e..0bdd0dd900a3 100644
--- a/pkgs/development/compilers/gcc-4.5/default.nix
+++ b/pkgs/development/compilers/gcc-4.5/default.nix
@@ -279,6 +279,8 @@ stdenv.mkDerivation ({
   passthru = { inherit langC langCC langAda langFortran langTreelang langVhdl
       enableMultilib version; };
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://gcc.gnu.org/;
     license = "GPLv3+";  # runtime support libraries are typically LGPLv3+
diff --git a/pkgs/development/compilers/gcc-apple/default.nix b/pkgs/development/compilers/gcc-apple/default.nix
index 8006bd4426d7..3346a4e327a5 100644
--- a/pkgs/development/compilers/gcc-apple/default.nix
+++ b/pkgs/development/compilers/gcc-apple/default.nix
@@ -21,6 +21,8 @@ stdenv.mkDerivation ({
       sha256 = "a7d8041e50e110f5a503e188a05cb217f0c99c51f248a0a1387cc07a0b6f167f";
     }) ;
 
+  enableParallelBuilding = true;
+
   sourceRoot = "gcc_42-5574/";
   patches =
     [./pass-cxxcpp.patch ./debug_list.patch]
diff --git a/pkgs/development/compilers/gcc-apple64/default.nix b/pkgs/development/compilers/gcc-apple64/default.nix
index b87cd596a5b3..ec16fae79774 100644
--- a/pkgs/development/compilers/gcc-apple64/default.nix
+++ b/pkgs/development/compilers/gcc-apple64/default.nix
@@ -21,6 +21,8 @@ stdenv.mkDerivation ({
       sha256 = "1fy6j41rhxdsm19sib9wygjl5l54g8pm13c6y5x13f40mavw1mma";
     }) ;
 
+  enableParallelBuilding = true;
+
   libstdcxx = "libstdcxx-39";
   sourceRoot = "gcc-5646/";
   patches =
diff --git a/pkgs/development/interpreters/perl-5.10/default.nix b/pkgs/development/interpreters/perl-5.10/default.nix
index 31168291e3d1..76928d104481 100644
--- a/pkgs/development/interpreters/perl-5.10/default.nix
+++ b/pkgs/development/interpreters/perl-5.10/default.nix
@@ -39,6 +39,8 @@ stdenv.mkDerivation rec {
 
   dontAddPrefix = true;
 
+  enableParallelBuilding = true;
+
   preConfigure =
     ''
       configureFlags="$configureFlags -Dprefix=$out -Dman1dir=$out/share/man/man1 -Dman3dir=$out/share/man/man3"
diff --git a/pkgs/development/libraries/glibc-2.11/builder.sh b/pkgs/development/libraries/glibc-2.11/builder.sh
index 11cd9dbd9687..9a1c1490019a 100644
--- a/pkgs/development/libraries/glibc-2.11/builder.sh
+++ b/pkgs/development/libraries/glibc-2.11/builder.sh
@@ -17,7 +17,7 @@ postConfigure() {
 
 postInstall() {
     if test -n "$installLocales"; then
-        make localedata/install-locales
+        make -j${NIX_BUILD_CORES:-1} -l${NIX_BUILD_CORES:-1} localedata/install-locales
     fi
     
     test -f $out/etc/ld.so.cache && rm $out/etc/ld.so.cache
diff --git a/pkgs/development/libraries/glibc-2.11/common.nix b/pkgs/development/libraries/glibc-2.11/common.nix
index f227db3c632d..4888308aaf3f 100644
--- a/pkgs/development/libraries/glibc-2.11/common.nix
+++ b/pkgs/development/libraries/glibc-2.11/common.nix
@@ -29,7 +29,9 @@ stdenv.mkDerivation ({
 
   inherit (stdenv) is64bit;
 
-  patches = 
+  enableParallelBuilding = true;
+
+  patches =
     stdenv.lib.optional (fetchgit == null)
     /* Fix for NIXPKGS-79: when doing host name lookups, when
        nsswitch.conf contains a line like
diff --git a/pkgs/development/libraries/glibc-2.5/builder.sh b/pkgs/development/libraries/glibc-2.5/builder.sh
index 695a3a1ab3da..4cd0132e3700 100644
--- a/pkgs/development/libraries/glibc-2.5/builder.sh
+++ b/pkgs/development/libraries/glibc-2.5/builder.sh
@@ -38,7 +38,7 @@ postConfigure() {
 
 postInstall() {
     if test -n "$installLocales"; then
-        make localedata/install-locales
+        make -j${NIX_BUILD_CORES:-1} -l${NIX_BUILD_CORES:-1} localedata/install-locales
     fi
     rm $out/etc/ld.so.cache
     (cd $out/include && ln -s $kernelHeaders/include/* .) || exit 1
diff --git a/pkgs/development/libraries/glibc-2.5/default.nix b/pkgs/development/libraries/glibc-2.5/default.nix
index abfc3d0f4395..83447d8fe8a9 100644
--- a/pkgs/development/libraries/glibc-2.5/default.nix
+++ b/pkgs/development/libraries/glibc-2.5/default.nix
@@ -30,6 +30,8 @@ stdenv.mkDerivation {
   # the symbol __i686.get_pc_thunk.dx to be mangled.
   NIX_CFLAGS_COMPILE = "-U__i686";
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://www.gnu.org/software/libc/;
     description = "The GNU C Library";
diff --git a/pkgs/development/libraries/gmp/4.3.1.nix b/pkgs/development/libraries/gmp/4.3.1.nix
index 17455b9f1dd4..5f83d9ae46dc 100644
--- a/pkgs/development/libraries/gmp/4.3.1.nix
+++ b/pkgs/development/libraries/gmp/4.3.1.nix
@@ -16,6 +16,8 @@ stdenv.mkDerivation rec {
 
   doCheck = true;
 
+  enableParallelBuilding = true;
+
   meta = {
     description = "A free library for arbitrary precision arithmetic, operating on signed integers, rational numbers, and floating point numbers";
     homepage = http://gmplib.org/;
diff --git a/pkgs/development/libraries/gmp/default.nix b/pkgs/development/libraries/gmp/default.nix
index e2f8a900bda3..08a03d715c2f 100644
--- a/pkgs/development/libraries/gmp/default.nix
+++ b/pkgs/development/libraries/gmp/default.nix
@@ -18,6 +18,8 @@ stdenv.mkDerivation rec {
 
   doCheck = true;
 
+  enableParallelBuilding = true;
+
   meta = {
     description = "GMP, the GNU multiple precision arithmetic library";
 
diff --git a/pkgs/development/libraries/mpfr/default.nix b/pkgs/development/libraries/mpfr/default.nix
index dea0113cc69f..1bfd14482003 100644
--- a/pkgs/development/libraries/mpfr/default.nix
+++ b/pkgs/development/libraries/mpfr/default.nix
@@ -12,6 +12,8 @@ stdenv.mkDerivation rec {
 
   doCheck = true;
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://www.mpfr.org/;
     description = "GNU MPFR, a library for multiple-precision floating-point arithmetic";
diff --git a/pkgs/development/libraries/qt-4.x/4.5/default.nix b/pkgs/development/libraries/qt-4.x/4.5/default.nix
index d7d69a3fa8e5..bee2c4e46793 100644
--- a/pkgs/development/libraries/qt-4.x/4.5/default.nix
+++ b/pkgs/development/libraries/qt-4.x/4.5/default.nix
@@ -74,6 +74,8 @@ stdenv.mkDerivation {
     ${if keepDocumentation == false then "rm -rf $out/doc" else ""}
   '';
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://www.qtsoftware.com/downloads/opensource/appdev/linux-x11-cpp;
     description = "A cross-platform application framework for C++";
diff --git a/pkgs/development/libraries/qt-4.x/4.6/default.nix b/pkgs/development/libraries/qt-4.x/4.6/default.nix
index 707f261f6001..914d629e5c00 100644
--- a/pkgs/development/libraries/qt-4.x/4.6/default.nix
+++ b/pkgs/development/libraries/qt-4.x/4.6/default.nix
@@ -89,6 +89,8 @@ stdenv.mkDerivation rec {
 
   postInstall = if useDocs then "rm -rf $out/share/doc/${name}/{html,src}" else "";
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://qt.nokia.com/products;
     description = "A cross-platform application framework for C++";
diff --git a/pkgs/development/libraries/qt-4.x/4.7/default.nix b/pkgs/development/libraries/qt-4.x/4.7/default.nix
index 0bb61a07bcb6..d02f96766522 100644
--- a/pkgs/development/libraries/qt-4.x/4.7/default.nix
+++ b/pkgs/development/libraries/qt-4.x/4.7/default.nix
@@ -96,6 +96,8 @@ stdenv.mkDerivation rec {
 
   postInstall = if useDocs then "rm -rf $out/share/doc/${name}/{html,src}" else "";
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://qt.nokia.com/products;
     description = "A cross-platform application framework for C++";
diff --git a/pkgs/tools/misc/coreutils/default.nix b/pkgs/tools/misc/coreutils/default.nix
index a5631079fbb1..2d1052e3a0f9 100644
--- a/pkgs/tools/misc/coreutils/default.nix
+++ b/pkgs/tools/misc/coreutils/default.nix
@@ -31,6 +31,8 @@ stdenv.mkDerivation rec {
   # and {Open,Free}BSD.
   doCheck = (stdenv ? glibc);
 
+  enableParallelBuilding = true;
+
   meta = {
     homepage = http://www.gnu.org/software/coreutils/;
     description = "The basic file, shell and text manipulation utilities of the GNU operating system";