diff --git a/pkgs/BUGS b/pkgs/BUGS
new file mode 100644
index 000000000000..31cb7dc51eaf
--- /dev/null
+++ b/pkgs/BUGS
@@ -0,0 +1,50 @@
+* If NIX_DEBUG is turned on (set to "1"), autoconf configure scripts
+  may fail to find the correct preprocessor:
+
+    checking how to run the C preprocessor... /lib/cpp
+
+
+* When building gcc using a Nix gcc, generated libraries link against
+  the libraries of the latter:
+
+    $ ldd /nix/store/3b1d3995c4edbf026be5c73f66f69245-gcc-3.3.3/lib/libstdc++.so
+    ...
+    libgcc_s.so.1 => /nix/store/1f19e61d1b7051f1131f78b41b2a0e7e-gcc-3.3.2/lib/libgcc_s.so.1 (0x400de000)
+    (wrong! should be .../3b1d.../lib/libgcc_s...)
+    ...
+
+
+* Subtle problems can occur if the Nix store directory or one of its
+  parents is a symlink.  E.g., purity checks can barf:
+
+    impure path `/data/nix/store/099cd9aee7d056a9922fd6dd116a3f5c-gcc-3.3.3/bin/../lib/gcc-lib/i686-pc-linux-gnu/3.3.3/crtbegin.o' used in link
+
+  (This happened because /nix was a symlink to /data/nix.)  Maybe we
+  should disallow this entirely, since, exactly because it is
+  perfectly legal for a builder to expand a symlink, we can end up
+  with derivates referring to paths that existed in the build
+  environment but not in the target environment.
+
+  Disallowing this can be highly inconvenient, since it makes it
+  harder to move the Nix store to a different file system.  (On Linux,
+  `bind' mounts can help here.) 
+
+
+* In libXt:
+
+/bin/sh ./libtool --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I.     -DXTHREADS -DXUSE_MTSAFE_API -I/nix/store/aadf0bd4a908da11d14f6538503b8408-libX11-6.2.1/include -I/nix/store/ba366e3b944ead64ec9b0490bb615874-xproto-6.6.1/include   -I./include/X11 -g -O2 -c -o ActionHook.lo `test -f 'ActionHook.c' || echo './'`ActionHook.c
+mkdir .libs
+ gcc -DHAVE_CONFIG_H -I. -I. -I. -DXTHREADS -DXUSE_MTSAFE_API -I/nix/store/aadf0bd4a908da11d14f6538503b8408-libX11-6.2.1/include -I/nix/store/ba366e3b944ead64ec9b0490bb615874-xproto-6.6.1/include -I./include/X11 -g -O2 -c ActionHook.c  -fPIC -DPIC -o .libs/ActionHook.o
+In file included from IntrinsicI.h:55,
+                 from ActionHook.c:69:
+include/X11/IntrinsicP.h:54:27: X11/Intrinsic.h: No such file or directory
+
+
+* Then:
+
+ gcc -DHAVE_CONFIG_H -I. -I. -I. -DXTHREADS -DXUSE_MTSAFE_API -I/nix/store/aadf0bd4a908da11d14f6538503b8408-libX11-6.2.1/include -I/nix/store/ba366e3b944ead64ec9b0490bb615874-xproto-6.6.1/include -I./include -I./include/X11 -g -O2 -c ActionHook.c  -fPIC -DPIC -o .libs/ActionHook.o
+In file included from IntrinsicI.h:55,
+                 from ActionHook.c:69:
+include/X11/IntrinsicP.h:202:25: X11/ObjectP.h: No such file or directory
+
+(moved to include/X11; should edit include/Makefile.am)
\ No newline at end of file
diff --git a/pkgs/TODO b/pkgs/TODO
new file mode 100644
index 000000000000..42bd96b25d41
--- /dev/null
+++ b/pkgs/TODO
@@ -0,0 +1,6 @@
+* Add $propagatedBuildInputs to $buildInputs in setup.sh.  Then clean
+  up freedesktop/libX11/default.nix, libSM.
+
+* In setup.sh: create $out prior to calling `make install'.
+
+* In setup.sh: `mkdir -f' -> `if ! test -x $out/...; then mkdir ...'.
diff --git a/pkgs/development/libraries/freedesktop/libICE/builder.sh b/pkgs/development/libraries/freedesktop/libICE/builder.sh
new file mode 100755
index 000000000000..a73f5a6d5b8d
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libICE/builder.sh
@@ -0,0 +1,3 @@
+#! /bin/sh -e
+. $stdenv/setup
+genericBuild
diff --git a/pkgs/development/libraries/freedesktop/libICE/default.nix b/pkgs/development/libraries/freedesktop/libICE/default.nix
new file mode 100644
index 000000000000..58dc8794c180
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libICE/default.nix
@@ -0,0 +1,13 @@
+{stdenv, fetchurl, pkgconfig, libX11}:
+
+derivation {
+  name = "libICE-6.3.2";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/libICE-6.3.2.tar.bz2;
+    md5 = "06db02e3df846b127a6e2dc3e345039c";
+  };
+  buildInputs = [pkgconfig libX11];
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/libSM/builder.sh b/pkgs/development/libraries/freedesktop/libSM/builder.sh
new file mode 100755
index 000000000000..3f0cb5a15052
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libSM/builder.sh
@@ -0,0 +1,8 @@
+#! /bin/sh -e
+. $stdenv/setup
+genericBuild
+
+if test -n "$_propagatedBuildInputs"; then
+    if ! test -x $out/nix-support; then mkdir $out/nix-support; fi
+    echo "$_propagatedBuildInputs" > $out/nix-support/propagated-build-inputs
+fi
diff --git a/pkgs/development/libraries/freedesktop/libSM/default.nix b/pkgs/development/libraries/freedesktop/libSM/default.nix
new file mode 100644
index 000000000000..28295b4e9b42
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libSM/default.nix
@@ -0,0 +1,14 @@
+{stdenv, fetchurl, pkgconfig, libX11, libICE}:
+
+derivation {
+  name = "libSM-6.0.2";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/libSM-6.0.2.tar.bz2;
+    md5 = "0ecc3ec75391d9158f25a94a652bd387";
+  };
+  buildInputs = [pkgconfig libX11 libICE];
+  _propagatedBuildInputs = [libICE];
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/libX11/builder.sh b/pkgs/development/libraries/freedesktop/libX11/builder.sh
new file mode 100755
index 000000000000..bb81d4bdb325
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libX11/builder.sh
@@ -0,0 +1,10 @@
+#! /bin/sh
+
+. $stdenv/setup
+
+genericBuild
+
+if test -n "$_propagatedBuildInputs"; then
+    if ! test -x $out/nix-support; then mkdir $out/nix-support; fi
+    echo "$_propagatedBuildInputs" > $out/nix-support/propagated-build-inputs
+fi
diff --git a/pkgs/development/libraries/freedesktop/libX11/default.nix b/pkgs/development/libraries/freedesktop/libX11/default.nix
new file mode 100644
index 000000000000..f432a03a3f61
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libX11/default.nix
@@ -0,0 +1,14 @@
+{stdenv, fetchurl, pkgconfig, xproto, xextensions, libXtrans, libXau}:
+
+derivation {
+  name = "libX11-6.2.1";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/libX11-6.2.1.tar.bz2;
+    md5 = "59b6fa7cd6fe7ee1da92fd1b56d1cee3";
+  };
+  buildInputs = [pkgconfig xproto xextensions libXtrans libXau];
+  _propagatedBuildInputs = [xproto xextensions libXtrans libXau];
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/libXau/builder.sh b/pkgs/development/libraries/freedesktop/libXau/builder.sh
new file mode 100755
index 000000000000..dc844d758a83
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXau/builder.sh
@@ -0,0 +1,5 @@
+#! /bin/sh
+
+. $stdenv/setup
+
+genericBuild
diff --git a/pkgs/development/libraries/freedesktop/libXau/default.nix b/pkgs/development/libraries/freedesktop/libXau/default.nix
new file mode 100644
index 000000000000..be6d6e262c0a
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXau/default.nix
@@ -0,0 +1,13 @@
+{stdenv, fetchurl, pkgconfig, xproto}:
+
+derivation {
+  name = "libXau-0.1.1";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/libXau-0.1.1.tar.bz2;
+    md5 = "3d747ada4a7d17538fa21c62d5608656";
+  };
+  buildInputs = [pkgconfig xproto];
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/libXt/builder.sh b/pkgs/development/libraries/freedesktop/libXt/builder.sh
new file mode 100755
index 000000000000..a73f5a6d5b8d
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXt/builder.sh
@@ -0,0 +1,3 @@
+#! /bin/sh -e
+. $stdenv/setup
+genericBuild
diff --git a/pkgs/development/libraries/freedesktop/libXt/default.nix b/pkgs/development/libraries/freedesktop/libXt/default.nix
new file mode 100644
index 000000000000..5d2e62c8c33f
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXt/default.nix
@@ -0,0 +1,15 @@
+{stdenv, fetchurl, pkgconfig, libX11, libSM, patch}:
+
+derivation {
+  name = "libXt-0.1.4";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/libXt-0.1.4.tar.bz2;
+    md5 = "32b6528c9deb058d1a9ed17ffa848df8";
+  };
+  buildInputs = [pkgconfig libX11 libSM patch];
+  # This patch should become unnecessary soon; already been fixed in CVS.
+  patches = [./patch];
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/libXt/patch b/pkgs/development/libraries/freedesktop/libXt/patch
new file mode 100644
index 000000000000..85cd4c87c60b
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXt/patch
@@ -0,0 +1,360 @@
+diff -x '*~' -rcN libXt-0.1.4-orig/include/X11/ObjectP.h libXt-0.1.4/include/X11/ObjectP.h
+*** libXt-0.1.4-orig/include/X11/ObjectP.h	1970-01-01 01:00:00.000000000 +0100
+--- libXt-0.1.4/include/X11/ObjectP.h	2004-01-14 06:09:40.000000000 +0100
+***************
+*** 0 ****
+--- 1,139 ----
++ /* $Xorg: ObjectP.h,v 1.4 2001/02/09 02:03:56 xorgcvs Exp $ */
++ 
++ /***********************************************************
++ 
++ Copyright 1987, 1988, 1994, 1998  The Open Group
++ 
++ Permission to use, copy, modify, distribute, and sell this software and its
++ documentation for any purpose is hereby granted without fee, provided that
++ the above copyright notice appear in all copies and that both that
++ copyright notice and this permission notice appear in supporting
++ documentation.
++ 
++ The above copyright notice and this permission notice shall be included in
++ all copies or substantial portions of the Software.
++ 
++ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
++ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
++ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
++ OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
++ AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
++ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
++ 
++ Except as contained in this notice, the name of The Open Group shall not be
++ used in advertising or otherwise to promote the sale, use or other dealings
++ in this Software without prior written authorization from The Open Group.
++ 
++ 
++ Copyright 1987, 1988 by Digital Equipment Corporation, Maynard, Massachusetts.
++ 
++                         All Rights Reserved
++ 
++ Permission to use, copy, modify, and distribute this software and its 
++ documentation for any purpose and without fee is hereby granted, 
++ provided that the above copyright notice appear in all copies and that
++ both that copyright notice and this permission notice appear in 
++ supporting documentation, and that the name of Digital not be
++ used in advertising or publicity pertaining to distribution of the
++ software without specific, written prior permission.  
++ 
++ DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
++ ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
++ DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
++ ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
++ WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
++ ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
++ SOFTWARE.
++ 
++ ******************************************************************/
++ 
++ #ifndef _Xt_ObjectP_h_
++ #define _Xt_ObjectP_h_
++ 
++ #include <X11/Object.h>
++ 
++ /**********************************************************
++  * Object Instance Data Structures
++  *
++  **********************************************************/
++ /* these fields match CorePart and can not be changed */
++ 
++ typedef struct _ObjectPart {
++     Widget          self;               /* pointer to widget itself          */
++     WidgetClass     widget_class;       /* pointer to Widget's ClassRec      */
++     Widget          parent;             /* parent widget                     */
++     XrmName         xrm_name;           /* widget resource name quarkified   */
++     Boolean         being_destroyed;    /* marked for destroy                */
++     XtCallbackList  destroy_callbacks;  /* who to call when widget destroyed */
++     XtPointer       constraints;        /* constraint record                 */
++ } ObjectPart;
++ 
++ typedef struct _ObjectRec {
++     ObjectPart  object;
++ } ObjectRec;
++ 
++ /********************************************************
++  * Object Class Data Structures
++  *
++  ********************************************************/
++ /* these fields match CoreClassPart and can not be changed */
++ /* ideally these structures would only contain the fields required;
++    but because the CoreClassPart cannot be changed at this late date
++    extraneous fields are necessary to make the field offsets match */
++ 
++ typedef struct _ObjectClassPart {
++ 
++     WidgetClass     superclass;         /* pointer to superclass ClassRec   */
++     String          class_name;         /* widget resource class name       */
++     Cardinal        widget_size;        /* size in bytes of widget record   */
++     XtProc          class_initialize;   /* class initialization proc        */
++     XtWidgetClassProc class_part_initialize; /* dynamic initialization      */
++     XtEnum          class_inited;       /* has class been initialized?      */
++     XtInitProc      initialize;         /* initialize subclass fields       */
++     XtArgsProc      initialize_hook;    /* notify that initialize called    */
++     XtProc          obj1;		/* NULL                             */
++     XtPointer       obj2;               /* NULL                             */
++     Cardinal        obj3;               /* NULL                             */
++     XtResourceList  resources;          /* resources for subclass fields    */
++     Cardinal        num_resources;      /* number of entries in resources   */
++     XrmClass        xrm_class;          /* resource class quarkified        */
++     Boolean         obj4;               /* NULL                             */
++     XtEnum          obj5;               /* NULL                             */
++     Boolean         obj6;               /* NULL				    */
++     Boolean         obj7;               /* NULL                             */
++     XtWidgetProc    destroy;            /* free data for subclass pointers  */
++     XtProc          obj8;               /* NULL                             */
++     XtProc          obj9;               /* NULL			            */
++     XtSetValuesFunc set_values;         /* set subclass resource values     */
++     XtArgsFunc      set_values_hook;    /* notify that set_values called    */
++     XtProc          obj10;              /* NULL                             */
++     XtArgsProc      get_values_hook;    /* notify that get_values called    */
++     XtProc          obj11;              /* NULL                             */
++     XtVersionType   version;            /* version of intrinsics used       */
++     XtPointer       callback_private;   /* list of callback offsets         */
++     String          obj12;              /* NULL                             */
++     XtProc          obj13;              /* NULL                             */
++     XtProc          obj14;              /* NULL                             */
++     XtPointer       extension;          /* pointer to extension record      */
++ }ObjectClassPart;
++ 
++ typedef struct {
++     XtPointer next_extension;	/* 1st 4 required for all extension records */
++     XrmQuark record_type;	/* NULLQUARK; when on ObjectClassPart */
++     long version;		/* must be XtObjectExtensionVersion */
++     Cardinal record_size;	/* sizeof(ObjectClassExtensionRec) */
++     XtAllocateProc allocate;
++     XtDeallocateProc deallocate;
++ } ObjectClassExtensionRec, *ObjectClassExtension;
++ 
++ typedef struct _ObjectClassRec {
++     ObjectClassPart object_class;
++ } ObjectClassRec;
++ 
++ externalref ObjectClassRec objectClassRec;
++ 
++ #define XtObjectExtensionVersion 1L
++ #define XtInheritAllocate ((XtAllocateProc) _XtInherit)
++ #define XtInheritDeallocate ((XtDeallocateProc) _XtInherit)
++ 
++ #endif /*_Xt_ObjectP_h_*/
+diff -x '*~' -rcN libXt-0.1.4-orig/Makefile.in libXt-0.1.4/Makefile.in
+*** libXt-0.1.4-orig/Makefile.in	2004-01-17 05:14:05.000000000 +0100
+--- libXt-0.1.4/Makefile.in	2004-03-27 22:27:07.000000000 +0100
+***************
+*** 163,169 ****
+  
+  SUBDIRS = include util
+  
+! AM_CFLAGS = $(RENDER_CFLAGS) $(X_CFLAGS) -I$(top_srcdir)/include/X11
+  
+  lib_LTLIBRARIES = libXt.la
+  
+--- 163,169 ----
+  
+  SUBDIRS = include util
+  
+! AM_CFLAGS = $(RENDER_CFLAGS) $(X_CFLAGS) -I$(top_srcdir)/include -I$(top_srcdir)/include/X11
+  
+  lib_LTLIBRARIES = libXt.la
+  
+***************
+*** 899,904 ****
+--- 899,905 ----
+  	$(top_builddir)/util/makestrs $(STRINGSABIOPTIONS) < $(STRING_LIST) > StringDefs.c
+  	install -d include/X11/
+  	install -m644 $(top_builddir)/StringDefs.h include/X11/
++ 	install -m644 $(top_builddir)/Shell.h include/X11/
+  
+  $(top_builddir)/util/makestrs$(EXEEXT): force
+  	cd util; $(MAKE)
+diff -x '*~' -rcN libXt-0.1.4-orig/ObjectP.h libXt-0.1.4/ObjectP.h
+*** libXt-0.1.4-orig/ObjectP.h	2004-01-14 06:09:40.000000000 +0100
+--- libXt-0.1.4/ObjectP.h	1970-01-01 01:00:00.000000000 +0100
+***************
+*** 1,139 ****
+- /* $Xorg: ObjectP.h,v 1.4 2001/02/09 02:03:56 xorgcvs Exp $ */
+- 
+- /***********************************************************
+- 
+- Copyright 1987, 1988, 1994, 1998  The Open Group
+- 
+- Permission to use, copy, modify, distribute, and sell this software and its
+- documentation for any purpose is hereby granted without fee, provided that
+- the above copyright notice appear in all copies and that both that
+- copyright notice and this permission notice appear in supporting
+- documentation.
+- 
+- The above copyright notice and this permission notice shall be included in
+- all copies or substantial portions of the Software.
+- 
+- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+- OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+- AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+- 
+- Except as contained in this notice, the name of The Open Group shall not be
+- used in advertising or otherwise to promote the sale, use or other dealings
+- in this Software without prior written authorization from The Open Group.
+- 
+- 
+- Copyright 1987, 1988 by Digital Equipment Corporation, Maynard, Massachusetts.
+- 
+-                         All Rights Reserved
+- 
+- Permission to use, copy, modify, and distribute this software and its 
+- documentation for any purpose and without fee is hereby granted, 
+- provided that the above copyright notice appear in all copies and that
+- both that copyright notice and this permission notice appear in 
+- supporting documentation, and that the name of Digital not be
+- used in advertising or publicity pertaining to distribution of the
+- software without specific, written prior permission.  
+- 
+- DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+- ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+- DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+- ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+- WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+- ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+- SOFTWARE.
+- 
+- ******************************************************************/
+- 
+- #ifndef _Xt_ObjectP_h_
+- #define _Xt_ObjectP_h_
+- 
+- #include <X11/Object.h>
+- 
+- /**********************************************************
+-  * Object Instance Data Structures
+-  *
+-  **********************************************************/
+- /* these fields match CorePart and can not be changed */
+- 
+- typedef struct _ObjectPart {
+-     Widget          self;               /* pointer to widget itself          */
+-     WidgetClass     widget_class;       /* pointer to Widget's ClassRec      */
+-     Widget          parent;             /* parent widget                     */
+-     XrmName         xrm_name;           /* widget resource name quarkified   */
+-     Boolean         being_destroyed;    /* marked for destroy                */
+-     XtCallbackList  destroy_callbacks;  /* who to call when widget destroyed */
+-     XtPointer       constraints;        /* constraint record                 */
+- } ObjectPart;
+- 
+- typedef struct _ObjectRec {
+-     ObjectPart  object;
+- } ObjectRec;
+- 
+- /********************************************************
+-  * Object Class Data Structures
+-  *
+-  ********************************************************/
+- /* these fields match CoreClassPart and can not be changed */
+- /* ideally these structures would only contain the fields required;
+-    but because the CoreClassPart cannot be changed at this late date
+-    extraneous fields are necessary to make the field offsets match */
+- 
+- typedef struct _ObjectClassPart {
+- 
+-     WidgetClass     superclass;         /* pointer to superclass ClassRec   */
+-     String          class_name;         /* widget resource class name       */
+-     Cardinal        widget_size;        /* size in bytes of widget record   */
+-     XtProc          class_initialize;   /* class initialization proc        */
+-     XtWidgetClassProc class_part_initialize; /* dynamic initialization      */
+-     XtEnum          class_inited;       /* has class been initialized?      */
+-     XtInitProc      initialize;         /* initialize subclass fields       */
+-     XtArgsProc      initialize_hook;    /* notify that initialize called    */
+-     XtProc          obj1;		/* NULL                             */
+-     XtPointer       obj2;               /* NULL                             */
+-     Cardinal        obj3;               /* NULL                             */
+-     XtResourceList  resources;          /* resources for subclass fields    */
+-     Cardinal        num_resources;      /* number of entries in resources   */
+-     XrmClass        xrm_class;          /* resource class quarkified        */
+-     Boolean         obj4;               /* NULL                             */
+-     XtEnum          obj5;               /* NULL                             */
+-     Boolean         obj6;               /* NULL				    */
+-     Boolean         obj7;               /* NULL                             */
+-     XtWidgetProc    destroy;            /* free data for subclass pointers  */
+-     XtProc          obj8;               /* NULL                             */
+-     XtProc          obj9;               /* NULL			            */
+-     XtSetValuesFunc set_values;         /* set subclass resource values     */
+-     XtArgsFunc      set_values_hook;    /* notify that set_values called    */
+-     XtProc          obj10;              /* NULL                             */
+-     XtArgsProc      get_values_hook;    /* notify that get_values called    */
+-     XtProc          obj11;              /* NULL                             */
+-     XtVersionType   version;            /* version of intrinsics used       */
+-     XtPointer       callback_private;   /* list of callback offsets         */
+-     String          obj12;              /* NULL                             */
+-     XtProc          obj13;              /* NULL                             */
+-     XtProc          obj14;              /* NULL                             */
+-     XtPointer       extension;          /* pointer to extension record      */
+- }ObjectClassPart;
+- 
+- typedef struct {
+-     XtPointer next_extension;	/* 1st 4 required for all extension records */
+-     XrmQuark record_type;	/* NULLQUARK; when on ObjectClassPart */
+-     long version;		/* must be XtObjectExtensionVersion */
+-     Cardinal record_size;	/* sizeof(ObjectClassExtensionRec) */
+-     XtAllocateProc allocate;
+-     XtDeallocateProc deallocate;
+- } ObjectClassExtensionRec, *ObjectClassExtension;
+- 
+- typedef struct _ObjectClassRec {
+-     ObjectClassPart object_class;
+- } ObjectClassRec;
+- 
+- externalref ObjectClassRec objectClassRec;
+- 
+- #define XtObjectExtensionVersion 1L
+- #define XtInheritAllocate ((XtAllocateProc) _XtInherit)
+- #define XtInheritDeallocate ((XtDeallocateProc) _XtInherit)
+- 
+- #endif /*_Xt_ObjectP_h_*/
+--- 0 ----
+diff -x '*~' -rcN libXt-0.1.4-orig/Xtos.h libXt-0.1.4/Xtos.h
+*** libXt-0.1.4-orig/Xtos.h	2004-01-14 06:09:41.000000000 +0100
+--- libXt-0.1.4/Xtos.h	2004-03-27 21:53:47.000000000 +0100
+***************
+*** 53,61 ****
+  #ifndef _Xtos_h
+  #define _Xtos_h
+  
+! #define ALLOCATE_LOCAL_FALLBACK(_size) XtMalloc((unsigned long)(_size))
+! #define DEALLOCATE_LOCAL_FALLBACK(_ptr) XtFree((XtPointer)(_ptr))
+! #include <X11/Xalloca.h>
+  
+  #ifdef CRAY
+  #define WORD64
+--- 53,77 ----
+  #ifndef _Xtos_h
+  #define _Xtos_h
+  
+! #if HAVE_ALLOCA
+! /* AIX requires this to be the first thing in the file.  */
+! # if HAVE_ALLOCA_H
+! #   include <alloca.h>
+! # else
+! #  ifdef _AIX
+!  #pragma alloca
+! #  else
+! #   ifndef alloca /* predefined by HP cc +Olibcalls */
+! char *alloca ();
+! #   endif
+! #  endif
+! # endif
+! #define ALLOCATE_LOCAL(size) alloca((int)(size))
+! #define DEALLOCATE_LOCAL(ptr) /* as nothing */
+! #else
+! #define ALLOCATE_LOCAL(_size) XtMalloc((unsigned long)(_size))
+! #define DEALLOCATE_LOCAL(_ptr) XtFree((XtPointer)(_ptr))
+! #endif
+  
+  #ifdef CRAY
+  #define WORD64
diff --git a/pkgs/development/libraries/freedesktop/libXtrans/builder.sh b/pkgs/development/libraries/freedesktop/libXtrans/builder.sh
new file mode 100755
index 000000000000..dc844d758a83
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXtrans/builder.sh
@@ -0,0 +1,5 @@
+#! /bin/sh
+
+. $stdenv/setup
+
+genericBuild
diff --git a/pkgs/development/libraries/freedesktop/libXtrans/default.nix b/pkgs/development/libraries/freedesktop/libXtrans/default.nix
new file mode 100644
index 000000000000..b5f9eb590b5b
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/libXtrans/default.nix
@@ -0,0 +1,12 @@
+{stdenv, fetchurl}:
+
+derivation {
+  name = "libXtrans-0.1";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/libXtrans-0.1.tar.bz2;
+    md5 = "a5ae4c7a75f930053b8327f7bd0c1361";
+  };
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/xextensions/builder.sh b/pkgs/development/libraries/freedesktop/xextensions/builder.sh
new file mode 100755
index 000000000000..dc844d758a83
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/xextensions/builder.sh
@@ -0,0 +1,5 @@
+#! /bin/sh
+
+. $stdenv/setup
+
+genericBuild
diff --git a/pkgs/development/libraries/freedesktop/xextensions/default.nix b/pkgs/development/libraries/freedesktop/xextensions/default.nix
new file mode 100644
index 000000000000..f22195154b98
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/xextensions/default.nix
@@ -0,0 +1,12 @@
+{stdenv, fetchurl}:
+
+derivation {
+  name = "xextensions-1.0.1";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/xextensions-1.0.1.tar.bz2;
+    md5 = "e61bca2a4757b736c9557dc8a7df2217";
+  };
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/freedesktop/xlibs/builder.sh b/pkgs/development/libraries/freedesktop/xlibs/builder.sh
new file mode 100755
index 000000000000..0151f8c7eba5
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/xlibs/builder.sh
@@ -0,0 +1,7 @@
+#! /bin/sh -e
+
+. $stdenv/setup
+
+mkdir $out
+mkdir $out/nix-support
+echo "$propagatedBuildInputs" > $out/nix-support/propagated-build-inputs
diff --git a/pkgs/development/libraries/freedesktop/xlibs/default.nix b/pkgs/development/libraries/freedesktop/xlibs/default.nix
new file mode 100644
index 000000000000..a5ef56ba46c7
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/xlibs/default.nix
@@ -0,0 +1,12 @@
+{stdenv, libX11, libXt}:
+
+derivation {
+  name = "xlib-1.0";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  propagatedBuildInputs = [libX11 libXt];
+  inherit stdenv;
+} // {
+  # For compatability with XFree86.
+  buildClientLibs = true;
+}
diff --git a/pkgs/development/libraries/freedesktop/xproto/builder.sh b/pkgs/development/libraries/freedesktop/xproto/builder.sh
new file mode 100755
index 000000000000..dc844d758a83
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/xproto/builder.sh
@@ -0,0 +1,5 @@
+#! /bin/sh
+
+. $stdenv/setup
+
+genericBuild
diff --git a/pkgs/development/libraries/freedesktop/xproto/default.nix b/pkgs/development/libraries/freedesktop/xproto/default.nix
new file mode 100644
index 000000000000..008590ef43df
--- /dev/null
+++ b/pkgs/development/libraries/freedesktop/xproto/default.nix
@@ -0,0 +1,12 @@
+{stdenv, fetchurl}:
+
+derivation {
+  name = "xproto-6.6.1";
+  system = stdenv.system;
+  builder = ./builder.sh;
+  src = fetchurl {
+    url = http://freedesktop.org/~xlibs/release/xlibs-1.0/xproto-6.6.1.tar.bz2;
+    md5 = "8a7546a607dcd61b2ee595c763fd7f85";
+  };
+  inherit stdenv;
+}
diff --git a/pkgs/development/libraries/gtk+-1/gdk-pixbuf/builder.sh b/pkgs/development/libraries/gtk+-1/gdk-pixbuf/builder.sh
index c3dc02383054..a73f5a6d5b8d 100755
--- a/pkgs/development/libraries/gtk+-1/gdk-pixbuf/builder.sh
+++ b/pkgs/development/libraries/gtk+-1/gdk-pixbuf/builder.sh
@@ -1,10 +1,3 @@
-#! /bin/sh
-
-buildinputs="$gtk $libtiff $libjpeg $libpng"
-. $stdenv/setup || exit 1
-
-tar xvfj $src || exit 1
-cd gdk-pixbuf-* || exit 1
-./configure --prefix=$out || exit 1
-make || exit 1
-make install || exit 1
+#! /bin/sh -e
+. $stdenv/setup
+genericBuild
diff --git a/pkgs/development/libraries/gtk+-1/gdk-pixbuf/default.nix b/pkgs/development/libraries/gtk+-1/gdk-pixbuf/default.nix
index 8fe9f5e0e140..1b05fdb0ea43 100644
--- a/pkgs/development/libraries/gtk+-1/gdk-pixbuf/default.nix
+++ b/pkgs/development/libraries/gtk+-1/gdk-pixbuf/default.nix
@@ -13,9 +13,6 @@ derivation {
     md5 = "05fcb68ceaa338614ab650c775efc2f2";
   };
 
-  stdenv = stdenv;
-  gtk = gtk;
-  libtiff = libtiff;
-  libjpeg = libjpeg;
-  libpng = libpng;
+  buildInputs = [gtk libtiff libjpeg libpng];
+  inherit stdenv;
 }
diff --git a/pkgs/development/libraries/gtk+-1/glib/builder.sh b/pkgs/development/libraries/gtk+-1/glib/builder.sh
index e6f721de3f4b..a73f5a6d5b8d 100755
--- a/pkgs/development/libraries/gtk+-1/glib/builder.sh
+++ b/pkgs/development/libraries/gtk+-1/glib/builder.sh
@@ -1,9 +1,3 @@
-#! /bin/sh
-
-. $stdenv/setup || exit 1
-
-tar xvfz $src || exit 1
-cd glib-* || exit 1
-./configure --prefix=$out || exit 1
-make || exit 1
-make install || exit 1
+#! /bin/sh -e
+. $stdenv/setup
+genericBuild
diff --git a/pkgs/development/libraries/gtk+-1/glib/default.nix b/pkgs/development/libraries/gtk+-1/glib/default.nix
index 7ae9be406b3e..eb61048c3af7 100644
--- a/pkgs/development/libraries/gtk+-1/glib/default.nix
+++ b/pkgs/development/libraries/gtk+-1/glib/default.nix
@@ -1,4 +1,6 @@
-{stdenv, fetchurl}: derivation {
+{stdenv, fetchurl}:
+
+derivation {
   name = "glib-1.2.10";
   system = stdenv.system;
   builder = ./builder.sh;
@@ -6,5 +8,5 @@
     url = ftp://ftp.gtk.org/pub/gtk/v1.2/glib-1.2.10.tar.gz;
     md5 = "6fe30dad87c77b91b632def29dd69ef9";
   };
-  stdenv = stdenv;
+  inherit stdenv;
 }
diff --git a/pkgs/development/libraries/gtk+-1/gtk+/builder.sh b/pkgs/development/libraries/gtk+-1/gtk+/builder.sh
index 14ba61f7054d..3f0cb5a15052 100755
--- a/pkgs/development/libraries/gtk+-1/gtk+/builder.sh
+++ b/pkgs/development/libraries/gtk+-1/gtk+/builder.sh
@@ -1,13 +1,8 @@
-#! /bin/sh
-
-buildinputs="$x11 $glib"
+#! /bin/sh -e
 . $stdenv/setup
+genericBuild
 
-tar xvfz $src
-cd gtk+-*
-./configure --prefix=$out
-make
-make install
-
-mkdir $out/nix-support
-echo "$x11 $glib" > $out/nix-support/propagated-build-inputs
+if test -n "$_propagatedBuildInputs"; then
+    if ! test -x $out/nix-support; then mkdir $out/nix-support; fi
+    echo "$_propagatedBuildInputs" > $out/nix-support/propagated-build-inputs
+fi
diff --git a/pkgs/development/libraries/gtk+-1/gtk+/default.nix b/pkgs/development/libraries/gtk+-1/gtk+/default.nix
index 856b2ffcad0e..fc8f45736d97 100644
--- a/pkgs/development/libraries/gtk+-1/gtk+/default.nix
+++ b/pkgs/development/libraries/gtk+-1/gtk+/default.nix
@@ -13,7 +13,7 @@ derivation {
     md5 = "4d5cb2fc7fb7830e4af9747a36bfce20";
   };
 
-  stdenv = stdenv;
-  x11 = x11;
-  glib = glib;
+  buildInputs = [x11 glib];
+  _propagatedBuildInputs = [x11 glib];
+  inherit stdenv;
 }
diff --git a/pkgs/system/all-packages-generic.nix b/pkgs/system/all-packages-generic.nix
index edabc1799b35..489a6b393ae2 100644
--- a/pkgs/system/all-packages-generic.nix
+++ b/pkgs/system/all-packages-generic.nix
@@ -9,6 +9,11 @@ rec {
   inherit stdenv;
 
 
+  ### Symbolic names.
+
+  x11 = xlibs; # !!! should be `x11ClientLibs' or some such
+
+
   ### BUILD SUPPORT
 
   fetchurl = (import ../build-support/fetchurl) {
@@ -104,8 +109,7 @@ rec {
   };
 
   graphviz = (import ../tools/graphics/graphviz) {
-    inherit fetchurl stdenv libpng libjpeg expat;
-    x11 = xfree86;
+    inherit fetchurl stdenv libpng libjpeg expat x11;
   };
 
 
@@ -371,13 +375,11 @@ rec {
   };
 
   fontconfig = (import ../development/libraries/fontconfig) {
-    inherit fetchurl stdenv freetype expat ed;
-    x11 = xfree86;
+    inherit fetchurl stdenv freetype expat ed x11;
   };
 
   xft = (import ../development/libraries/xft) {
-    inherit fetchurl stdenv pkgconfig fontconfig;
-    x11 = xfree86;
+    inherit fetchurl stdenv pkgconfig fontconfig x11;
   };
 
   zlib = (import ../development/libraries/zlib) {
@@ -414,14 +416,12 @@ rec {
   };
 
   pango = (import ../development/libraries/gtk+/pango) {
-    inherit fetchurl stdenv pkgconfig glib xft;
-    x11 = xfree86;
+    inherit fetchurl stdenv pkgconfig glib xft x11;
   };
 
   gtk = (import ../development/libraries/gtk+/gtk+) {
     inherit fetchurl stdenv pkgconfig glib atk pango perl
-            libtiff libjpeg libpng;
-    x11 = xfree86;
+            libtiff libjpeg libpng x11;
   };
 
   glib1 = (import ../development/libraries/gtk+-1/glib) {
@@ -429,8 +429,7 @@ rec {
   };
 
   gtk1 = (import ../development/libraries/gtk+-1/gtk+) {
-    inherit fetchurl stdenv;
-    x11 = xfree86;
+    inherit fetchurl stdenv x11;
     glib = glib1;
   };
 
@@ -541,9 +540,8 @@ rec {
   };
 
   zvbi = (import ../development/libraries/zvbi) {
-    inherit fetchurl stdenv libpng;
+    inherit fetchurl stdenv libpng x11;
     pngSupport = true;
-    x11 = xfree86;
     libpng = libpng;
   };
 
@@ -555,6 +553,44 @@ rec {
     inherit fetchurl stdenv zlib;
   };
 
+  xproto = (import ../development/libraries/freedesktop/xproto) {
+    inherit fetchurl stdenv;
+  };
+
+  xextensions = (import ../development/libraries/freedesktop/xextensions) {
+    inherit fetchurl stdenv;
+  };
+
+  libXtrans = (import ../development/libraries/freedesktop/libXtrans) {
+    inherit fetchurl stdenv;
+  };
+
+  libXau = (import ../development/libraries/freedesktop/libXau) {
+    inherit fetchurl stdenv pkgconfig xproto;
+  };
+
+  libX11 = (import ../development/libraries/freedesktop/libX11) {
+    inherit fetchurl stdenv pkgconfig xproto xextensions libXtrans libXau;
+  };
+
+
+  libICE = (import ../development/libraries/freedesktop/libICE) {
+    inherit fetchurl stdenv pkgconfig libX11;
+  };
+
+  libSM = (import ../development/libraries/freedesktop/libSM) {
+    inherit fetchurl stdenv pkgconfig libX11 libICE;
+  };
+
+  libXt = (import ../development/libraries/freedesktop/libXt) {
+    inherit fetchurl stdenv pkgconfig libX11 libSM;
+    patch = gnupatch;
+  };
+
+  xlibs = (import ../development/libraries/freedesktop/xlibs) {
+    inherit stdenv libX11 libXt;
+  };
+
   perlBerkeleyDB = (import ../development/perl-modules/BerkeleyDB) {
     inherit fetchurl stdenv perl db4;
   };
@@ -651,28 +687,24 @@ rec {
   };
 
   MPlayer = (import ../applications/video/MPlayer) {
-    inherit fetchurl stdenv freetype;
+    inherit fetchurl stdenv freetype x11;
     alsaSupport = true;
-    x11 = xfree86;
     alsa = alsaLib;
   };
 
   MPlayerPlugin = (import ../applications/video/mplayerplug-in) {
-    inherit fetchurl stdenv;
-    x11 = xfree86;
+    inherit fetchurl stdenv x11;
   };
 
   vlc = (import ../applications/video/vlc) {
     inherit fetchurl stdenv wxGTK libdvdcss libdvdplay
-            mpeg2dec a52dec libmad;
-    x11 = xfree86;
+            mpeg2dec a52dec libmad x11;
     alsa = alsaLib;
   };
 
   zapping = (import ../applications/video/zapping) {
     inherit fetchurl stdenv pkgconfig perl python libgnomeui libglade
-            scrollkeeper esound gettext zvbi libjpeg libpng;
-    x11 = xfree86;
+            scrollkeeper esound gettext zvbi libjpeg libpng x11;
     teletextSupport = true;
     jpegSupport = true;
     pngSupport = true;