Script to automatically checkout and create a snix release.

Merged trunk R.10943 back in
makeValidityRegistration only supports store paths for now ....
2008-03-04 14:16:16 +00:00 · 2008-03-04 13:30:53 +00:00 · 2008-03-04 12:15:55 +00:00 · 2008-02-07 00:06:04 +00:00 · 2008-02-06 23:58:00 +00:00 · 2008-01-13 16:36:27 +00:00
442 changed files with 41618 additions and 10089 deletions
--- a/8
+++ b/8
@@ -0,0 +1,8 @@
+The following people contributed to Nix, in alphabetical order:
+
+Martin Bravenboer
+Eelco Dolstra
+Niels Janssen
+Armijn Hemel
+Rob Vermaas
+Eelco Visser
--- a/644
+++ b/644
@@ -1,221 +1,397 @@
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-  9. The Free Software Foundation may publish revised and/or new versions
-of the General Public License from time to time.  Such new versions will
-be similar in spirit to the present version, but may differ in detail to
-address new problems or concerns.
+  13. The Free Software Foundation may publish revised and/or new
+versions of the Lesser General Public License from time to time.
+Such new versions will be similar in spirit to the present version,
+but may differ in detail to address new problems or concerns.

-Each version is given a distinguishing version number.  If the Program
-specifies a version number of this License which applies to it and "any
-later version", you have the option of following the terms and conditions
-either of that version or of any later version published by the Free
-Software Foundation.  If the Program does not specify a version number of
-this License, you may choose any version ever published by the Free Software
-Foundation.
-
-  10. If you wish to incorporate parts of the Program into other free
-programs whose distribution conditions are different, write to the author
-to ask for permission.  For software which is copyrighted by the Free
-Software Foundation, write to the Free Software Foundation; we sometimes
-make exceptions for this.  Our decision will be guided by the two goals
-of preserving the free status of all derivatives of our free software and
-of promoting the sharing and reuse of software generally.
+Each version is given a distinguishing version number.  If the Library
+specifies a version number of this License which applies to it and
+"any later version", you have the option of following the terms and
+conditions either of that version or of any later version published by
+the Free Software Foundation.  If the Library does not specify a
+license version number, you may choose any version ever published by
+the Free Software Foundation.
+
+  14. If you wish to incorporate parts of the Library into other free
+programs whose distribution conditions are incompatible with these,
+write to the author to ask for permission.  For software which is
+copyrighted by the Free Software Foundation, write to the Free
+Software Foundation; we sometimes make exceptions for this.  Our
+decision will be guided by the two goals of preserving the free status
+of all derivatives of our free software and of promoting the sharing
+and reuse of software generally.

 			    NO WARRANTY

-  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
-FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
-OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
-PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
-OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
-MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
-TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
-PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
-REPAIR OR CORRECTION.
+  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
+EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
+OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY
+KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
+LIBRARY IS WITH YOU.  SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME
+THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

-  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
-REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
-INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
-OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
-TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
-YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
-PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGES.
+  16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
+WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
+AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
+FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
+CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
+LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.

 		     END OF TERMS AND CONDITIONS

-	    How to Apply These Terms to Your New Programs
+           How to Apply These Terms to Your New Libraries

-  If you develop a new program, and you want it to be of the greatest
-possible use to the public, the best way to achieve this is to make it
-free software which everyone can redistribute and change under these terms.
+  If you develop a new library, and you want it to be of the greatest
+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms of the
+ordinary General Public License).

-  To do so, attach the following notices to the program.  It is safest
-to attach them to the start of each source file to most effectively
-convey the exclusion of warranty; and each file should have at least
-the "copyright" line and a pointer to where the full notice is found.
+  To apply these terms, attach the following notices to the library.  It is
+safest to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.

-    <one line to give the program's name and a brief idea of what it does.>
+    <one line to give the library's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.

-    This program is distributed in the hope that it will be useful,
+    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.

+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 Also add information on how to contact you by electronic and paper mail.

-If the program is interactive, make it output a short notice like this
-when it starts in an interactive mode:
-
-    Gnomovision version 69, Copyright (C) year  name of author
-    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
-    This is free software, and you are welcome to redistribute it
-    under certain conditions; type `show c' for details.
-
-The hypothetical commands `show w' and `show c' should show the appropriate
-parts of the General Public License.  Of course, the commands you use may
-be called something other than `show w' and `show c'; they could even be
-mouse-clicks or menu items--whatever suits your program.
-
 You should also get your employer (if you work as a programmer) or your
-school, if any, to sign a "copyright disclaimer" for the program, if
+school, if any, to sign a "copyright disclaimer" for the library, if
 necessary.  Here is a sample; alter the names:

-  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
-  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.

-  <signature of Ty Coon>, 1 April 1989
+  <signature of Ty Coon>, 1 April 1990
  Ty Coon, President of Vice

-This General Public License does not permit incorporating your program into
-proprietary programs.  If your program is a subroutine library, you may
-consider it more useful to permit linking proprietary applications with the
-library.  If this is what you want to do, use the GNU Library General
-Public License instead of this License.
+That's all there is to it!
+
+
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,6 @@
 SUBDIRS = externals src scripts corepkgs doc misc tests
-EXTRA_DIST = substitute.mk nix.spec nix.spec.in
+EXTRA_DIST = substitute.mk nix.spec nix.spec.in bootstrap.sh \
+  svn-revision nix.conf.example NEWS

 include ./substitute.mk

@@ -12,19 +13,49 @@ relname:
 	echo -n $(distdir) > relname

 install-data-local: init-state
+	$(INSTALL) -d $(DESTDIR)$(sysconfdir)/nix
+	$(INSTALL_DATA) $(srcdir)/nix.conf.example $(DESTDIR)$(sysconfdir)/nix
+	if ! test -e $(DESTDIR)$(sysconfdir)/nix/nix.conf; then \
+		$(INSTALL_DATA) $(srcdir)/nix.conf.example $(DESTDIR)$(sysconfdir)/nix/nix.conf; \
+	fi

 if INIT_STATE
+
+# For setuid operation, you can enable the following:
+# INIT_FLAGS = -g @NIX_GROUP@ -o @NIX_USER@
+# GROUP_WRITABLE = -m 775
+
 init-state:
-	$(INSTALL) -d $(DESTDIR)$(localstatedir)/nix
-	$(INSTALL) -d $(DESTDIR)$(localstatedir)/nix/db
-	$(INSTALL) -d $(DESTDIR)$(localstatedir)/log/nix
-	$(INSTALL) -d $(DESTDIR)$(localstatedir)/nix/profiles
-	$(INSTALL) -d $(DESTDIR)$(localstatedir)/nix/gcroots
-	$(INSTALL) -d $(DESTDIR)$(localstatedir)/nix/gcroots/tmp
-	rm -f $(DESTDIR)$(localstatedir)/nix/gcroots/profiles
-	ln -s $(localstatedir)/nix/profiles $(DESTDIR)$(localstatedir)/nix/gcroots/profiles
-	$(INSTALL) -d $(DESTDIR)$(prefix)/store
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/nix
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/nix/db
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/log/nix
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/log/nix/drvs
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/nix/profiles
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/nix/gcroots
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/nix/temproots
+	$(INSTALL) $(INIT_FLAGS) $(GROUP_WRITABLE) -d $(DESTDIR)$(localstatedir)/nix/gcroots/tmp
+	$(INSTALL) $(INIT_FLAGS) $(GROUP_WRITABLE) -d $(DESTDIR)$(localstatedir)/nix/gcroots/channels
+	ln -sfn $(localstatedir)/nix/profiles $(DESTDIR)$(localstatedir)/nix/gcroots/profiles
+	$(INSTALL) $(INIT_FLAGS) -d $(DESTDIR)$(localstatedir)/nix/userpool
+	$(INSTALL) $(INIT_FLAGS) -m 1777 -d $(DESTDIR)$(prefix)/store
+	$(INSTALL) $(INIT_FLAGS) $(GROUP_WRITABLE) -d $(DESTDIR)$(localstatedir)/nix/manifests
+	ln -sfn $(localstatedir)/nix/manifests $(DESTDIR)$(localstatedir)/nix/gcroots/manifests
 #	$(bindir)/nix-store --init
+
 else
 init-state:
 endif
+
+init-ext3cow-header-hack:
+	@echo "Symlinking ext3cow header file into src"
+	ln -sf $(ext3cowheader) src/libext3cow/
+
+svn-revision:
+	svnversion . > svn-revision
+
+all: init-ext3cow-header-hack
+
+all-local: NEWS
+
+NEWS: doc/manual/NEWS.txt
+	cp $(srcdir)/doc/manual/NEWS.txt NEWS
--- a/0
+++ b/0
--- a/8
+++ b/8
@@ -1,5 +1,9 @@
-                             *** Nix ***
-
 For installation and usage instructions, please read the manual, which
 can be found in `docs/manual/manual.html', and additionally at the Nix
 website at <http://www.cs.uu.nl/groups/ST/Trace/Nix>.
+
+
+Acknowledgments
+
+This product includes software developed by the OpenSSL Project for
+use in the OpenSSL Toolkit (http://www.OpenSSL.org/)
--- a/3
+++ b/3
@@ -0,0 +1,3 @@
+- runtimeStateArgs now must be set to someting (or it will see it as a hardcoded path)
+- import and export of state paths
+- 
--- a/aterm-gc.supp
+++ b/aterm-gc.supp
@@ -0,0 +1,184 @@
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:AT_isValidSymbol
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_isValidSymbol
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_isInsideValidTerm
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:AT_isInsideValidTerm
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_markTerm_young
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:AT_markTerm_young
+   fun:mark_memory_young
+   fun:mark_phase_young
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:AT_isValidSymbol
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_isValidSymbol
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_isInsideValidTerm
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:AT_isInsideValidTerm
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:AT_markTerm
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_markTerm
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:AT_markTerm
+   fun:mark_memory
+   fun:mark_phase
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Cond
+   fun:mark_phase_young
+   fun:AT_collect_minor
+}
+
+{
+   ATerm library conservatively scans for GC roots
+   Memcheck:Value4
+   fun:mark_phase_young
+   fun:AT_collect_minor
+}
+
+{
+   <insert a suppression name here>
+   Memcheck:Cond
+   fun:AT_isValidSymbol
+   fun:mark_phase_young
+   fun:AT_collect_minor
+}
+
+{
+   <insert a suppression name here>
+   Memcheck:Value4
+   fun:AT_isValidSymbol
+   fun:mark_phase_young
+   fun:AT_collect_minor
+}
+
+{
+   <insert a suppression name here>
+   Memcheck:Value4
+   fun:AT_isInsideValidTerm
+   fun:mark_phase_young
+   fun:AT_collect_minor
+}
+
+{
+   <insert a suppression name here>
+   Memcheck:Cond
+   fun:AT_isInsideValidTerm
+   fun:mark_phase_young
+   fun:AT_collect_minor
+}
--- a/blacklisting/check-env.pl
+++ b/blacklisting/check-env.pl
@@ -0,0 +1,252 @@
+#! /usr/bin/perl -w -I /home/eelco/.nix-profile/lib/site_perl
+
+use strict;
+use XML::LibXML;
+#use XML::Simple;
+
+my $blacklistFN = shift @ARGV;
+die unless defined $blacklistFN;
+my $userEnv = shift @ARGV;
+die unless defined $userEnv;
+
+
+# Read the blacklist.
+my $parser = XML::LibXML->new();
+my $blacklist = $parser->parse_file($blacklistFN)->getDocumentElement;
+
+#print $blacklist->toString() , "\n";
+
+
+# Get all the elements of the user environment.
+my $userEnvElems = `nix-store --query --references '$userEnv'`;
+die "cannot query user environment elements" if $? != 0;
+my @userEnvElems = split ' ', $userEnvElems;
+
+
+my %storePathHashes;
+
+
+sub getElemNodes {
+    my $node = shift;
+    my @elems = ();
+    foreach my $node ($node->getChildNodes) {
+        push @elems, $node if $node->nodeType == XML_ELEMENT_NODE;
+    }
+    return @elems;
+}
+
+
+my %referencesCache;
+sub getReferences {
+    my $path = shift;
+    return $referencesCache{$path} if defined $referencesCache{$path};
+    
+    my $references = `nix-store --query --references '$path'`;
+    die "cannot query references" if $? != 0;
+    $referencesCache{$path} = [split ' ', $references];
+    
+    return $referencesCache{$path};
+}
+
+
+my %attrsCache;
+sub getAttr {
+    my $path = shift;
+    my $name = shift;
+    my $key = "$path/$name";
+    return $referencesCache{$key} if defined $referencesCache{$key};
+
+    my $value = `nix-store --query --binding '$name' '$path' 2> /dev/null`;
+    $value = "" if $? != 0; # !!!
+    chomp $value;
+    $referencesCache{$key} = $value;
+
+    return $value;
+}
+
+
+sub evalCondition;
+
+
+sub traverse {
+    my $done = shift;
+    my $set = shift;
+    my $path = shift;
+    my $stopCondition = shift;
+
+    return if defined $done->{$path};
+    $done->{$path} = 1;
+    $set->{$path} = 1;
+
+#    print "  in $path\n";
+
+    if (!evalCondition({$path => 1}, $stopCondition)) {
+#        print "  STOPPING in $path\n";
+        return;
+    }
+
+    # Get the requisites of the deriver.
+
+    foreach my $reference (@{getReferences $path}) {
+        traverse($done, $set, $reference, $stopCondition);
+    }
+}
+
+
+sub evalSet {
+    my $inSet = shift;
+    my $expr = shift;
+    my $name = $expr->getName;
+    
+    if ($name eq "traverse") {
+        my $stopCondition = (getElemNodes $expr)[0];
+        my $done = { };
+        my $set = { };
+        foreach my $path (keys %{$inSet}) {
+            traverse($done, $set, $path, $stopCondition);
+        }
+        return $set;
+    }
+
+    else {
+        die "unknown element `$name'";
+    }
+}
+
+
+# Function for evaluating conditions.
+sub evalCondition {
+    my $storePaths = shift;
+    my $condition = shift;
+    my $elemName = $condition->getName;
+    
+    if ($elemName eq "containsSource") {
+        my $hash = $condition->attributes->getNamedItem("hash")->getValue;
+        foreach my $path (keys %{$storePathHashes{$hash}}) {
+            return 1 if defined $storePaths->{$path};
+        }
+        return 0;
+    }
+
+    elsif ($elemName eq "hasName") { 
+        my $nameRE = $condition->attributes->getNamedItem("name")->getValue;
+        foreach my $path (keys %{$storePaths}) {
+            return 1 if $path =~ /$nameRE/;
+        }
+        return 0;
+    }
+    
+    elsif ($elemName eq "hasAttr") { 
+        my $name = $condition->attributes->getNamedItem("name")->getValue;
+        my $valueRE = $condition->attributes->getNamedItem("value")->getValue;
+        foreach my $path (keys %{$storePaths}) {
+            if ($path =~ /\.drv$/) {
+                my $value = getAttr($path, $name);
+#                print "    $path $name $value\n";
+                return 1 if $value =~ /$valueRE/;
+            }
+        }
+        return 0;
+    }
+    
+    elsif ($elemName eq "and") {
+        my $result = 1;
+        foreach my $node (getElemNodes $condition) {
+            $result &= evalCondition($storePaths, $node);
+        }
+        return $result;
+    }
+
+    elsif ($elemName eq "not") {
+        return !evalCondition($storePaths, (getElemNodes $condition)[0]);
+    }
+    
+    elsif ($elemName eq "within") {
+        my @elems = getElemNodes $condition;
+        my $set = evalSet($storePaths, $elems[0]);
+        return evalCondition($set, $elems[1]);
+    }
+
+    elsif ($elemName eq "true") {
+        return 1;
+    }
+
+    elsif ($elemName eq "false") {
+        return 0;
+    }
+
+    else {
+        die "unknown element `$elemName'";
+    }
+}
+
+
+sub evalOr {
+    my $storePaths = shift;
+    my $nodes = shift;
+
+    my $result = 0;
+    foreach my $node (@{$nodes}) {
+        $result |= evalCondition($storePaths, $node);
+    }
+    
+    return $result;
+}
+
+
+# Iterate over all elements, check them.
+foreach my $userEnvElem (@userEnvElems) {
+
+    # Get the deriver of this path.
+    my $deriver = `nix-store --query --deriver '$userEnvElem'`;
+    die "cannot query deriver" if $? != 0;
+    chomp $deriver;
+
+    if ($deriver eq "unknown-deriver") {
+#        print "  deriver unknown, cannot check sources\n";
+        next;
+    }
+
+    print "CHECKING $userEnvElem\n";
+
+
+    # Get the requisites of the deriver.
+#    my $requisites = `nix-store --query --requisites --include-outputs '$deriver'`;
+#    die "cannot query requisites" if $? != 0;
+#    my @requisites = split ' ', $requisites;
+
+
+    # Get the hashes of the requisites.
+#    my $hashes = `nix-store --query --hash @requisites`;
+#    die "cannot query hashes" if $? != 0;
+#    my @hashes = split ' ', $hashes;
+#    for (my $i = 0; $i < scalar @requisites; $i++) {
+#        die unless $i < scalar @hashes;
+#        my $hash = $hashes[$i];
+#        $storePathHashes{$hash} = {} unless defined $storePathHashes{$hash};
+#        my $r = $storePathHashes{$hash}; # !!! fix
+#        $$r{$requisites[$i]} = 1;
+#    }
+
+
+    # Evaluate each blacklist item.
+    foreach my $item ($blacklist->getChildrenByTagName("item")) {
+        my $itemId = $item->getAttributeNode("id")->getValue;
+#        print "  CHECKING FOR $itemId\n";
+
+        my $condition = ($item->getChildrenByTagName("condition"))[0];
+        die unless $condition;
+
+        # Evaluate the condition.
+        my @elems = getElemNodes $condition;
+        if (evalOr({$deriver => 1}, \@elems)) {
+            # Oops, condition triggered.
+            my $reason = ($item->getChildrenByTagName("reason"))[0]->getChildNodes->to_literal;
+            $reason =~ s/\s+/ /g;
+            $reason =~ s/^\s+//g;
+
+            print "    VULNERABLE TO `$itemId': $reason\n";
+        }
+    }
+}
+
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -0,0 +1,7 @@
+#! /bin/sh -e
+mkdir -p config
+libtoolize --force --copy
+aclocal
+autoheader
+automake --add-missing --copy
+autoconf
--- a/configure.ac
+++ b/configure.ac
@@ -1,40 +1,91 @@
-AC_INIT(nix, "0.6")
+AC_INIT(nix, 0.12)
 AC_CONFIG_SRCDIR(README)
 AC_CONFIG_AUX_DIR(config)
-AM_INIT_AUTOMAKE
-
+AM_INIT_AUTOMAKE([dist-bzip2 foreign])
+        
 # Change to `1' to produce a `stable' release (i.e., the `preREVISION'
 # suffix is not added).
 STABLE=0

 # Put the revision number in the version.
 if test "$STABLE" != "1"; then
-    if REVISION=`test -d $srcdir/.svn && svnversion $srcdir 2> /dev/null`; then
-        VERSION="${VERSION}pre${REVISION}"
+    if REVISION=`test -d $srcdir/.svn && svnversion -n $srcdir 2> /dev/null`; then
+        VERSION=${VERSION}pre${REVISION}
    elif REVISION=`cat $srcdir/svn-revision 2> /dev/null`; then
-        VERSION="${VERSION}pre${REVISION}"
+        VERSION=${VERSION}pre${REVISION}
    fi
 fi

+AC_DEFINE_UNQUOTED(NIX_VERSION, ["$VERSION"], [version])
+
 AC_PREFIX_DEFAULT(/nix)

 AC_CANONICAL_HOST

+
 # Construct a Nix system name (like "i686-linux").
 AC_MSG_CHECKING([for the canonical Nix system name])
-#machine_name=`uname -m`
-#sys_name=`uname -s | tr [A-Z] [a-z]`
-#system="${machine_name}-${sys_name}"
+cpu_name=$(uname -p | tr 'A-Z ' 'a-z_')
+machine_name=$(uname -m | tr 'A-Z ' 'a-z_')
+
+case $machine_name in
+    i*86)
+        machine_name=i686
+        ;;
+    x86_64)
+        machine_name=x86_64
+        ;;
+    ppc)
+        machine_name=powerpc
+        ;;
+    *)
+        if test "$cpu_name" != "unknown"; then
+            machine_name=$cpu_name
+        fi
+        ;;
+esac
+
+sys_name=$(uname -s | tr 'A-Z ' 'a-z_')
+
+case $sys_name in
+    cygwin*)
+        sys_name=cygwin
+        ;;
+esac
+
 AC_ARG_WITH(system, AC_HELP_STRING([--with-system=SYSTEM],
  [platform identifier (e.g., `i686-linux')]),
-  system=$withval, system="$host_cpu-$host_os")
+  system=$withval, system="${machine_name}-${sys_name}")
 AC_MSG_RESULT($system)
 AC_SUBST(system)
 AC_DEFINE_UNQUOTED(SYSTEM, ["$system"], [platform identifier (`cpu-os')])

+
+# Windows-specific stuff.
+if test "$sys_name" = "cygwin"; then
+    # We cannot delete open files.
+    AC_DEFINE(CANNOT_DELETE_OPEN_FILES, 1, [Whether it is impossible to delete open files.])
+
+    # Shared libraries don't work, currently.
+    AC_DISABLE_SHARED
+    AC_ENABLE_STATIC
+fi
+
+
 AC_PROG_CC
 AC_PROG_CXX
-AC_PROG_RANLIB
+
+
+# We are going to use libtool.
+AC_DISABLE_STATIC
+AC_ENABLE_SHARED
+AC_PROG_LIBTOOL
+
+
+# Use 64-bit file system calls so that we can support files > 2 GiB.
+CFLAGS="-D_FILE_OFFSET_BITS=64 $CFLAGS"
+CXXFLAGS="-D_FILE_OFFSET_BITS=64 $CXXFLAGS"
+

 # Check for pubsetbuf.
 AC_MSG_CHECKING([for pubsetbuf])
@@ -47,38 +98,68 @@ static char buf[1024];]],
    AC_MSG_RESULT(no))
 AC_LANG_POP(C++)

+
+# Check for chroot support (requires chroot() and bind mounts).
+AC_CHECK_FUNCS([chroot])
+AC_CHECK_HEADERS([sys/param.h], [], [], [])
+AC_CHECK_HEADERS([sys/mount.h], [], [],
+[#ifdef HAVE_SYS_PARAM_H
+# include <sys/param.h>
+# endif
+])
+
+
 # Check for <locale>
 AC_LANG_PUSH(C++)
-AC_CHECK_HEADERS([locale])
+AC_CHECK_HEADERS([locale], [], [], [])
 AC_LANG_POP(C++)

+
 AC_DEFUN([NEED_PROG],
 [
 AC_PATH_PROG($1, $2)
 if test -z "$$1"; then
-    AC_MSG_ERROR([$1 is required])
+    AC_MSG_ERROR([$2 is required])
 fi
 ])

 NEED_PROG(curl, curl)
-NEED_PROG(bzip2, bzip2)
-NEED_PROG(bunzip2, bunzip2)
-NEED_PROG(shell, sh)
+NEED_PROG(shell, bash)
+NEED_PROG(patch, patch)
 AC_PATH_PROG(xmllint, xmllint, false)
 AC_PATH_PROG(xsltproc, xsltproc, false)
+AC_PATH_PROG(jing, jing, false) # needed because xmllint --relaxng seems broken
+AC_PATH_PROG(w3m, w3m, false)
 AC_PATH_PROG(flex, flex, false)
 AC_PATH_PROG(bison, bison, false)
 NEED_PROG(perl, perl)
+NEED_PROG(tar, tar)
+AC_PATH_PROG(dot, dot)
+AC_PATH_PROG(dblatex, dblatex)

-AC_ARG_WITH(docbook-catalog, AC_HELP_STRING([--with-docbook-catalog=PATH],
-  [path of the DocBook XML DTD]),
-  docbookcatalog=$withval, docbookcatalog=/docbook-dtd-missing)
-AC_SUBST(docbookcatalog)
+AC_PATH_PROG(openssl_prog, openssl, openssl) # if not found, call openssl in $PATH
+AC_SUBST(openssl_prog)
+AC_DEFINE_UNQUOTED(OPENSSL_PATH, ["$openssl_prog"], [Path of the OpenSSL binary])

-AC_ARG_WITH(docbook-ebnf-catalog, AC_HELP_STRING([--with-docbook-ebnf-catalog=PATH],
-  [path of the DocBook XML EBNF module DTD]),
-  docbookebnfcatalog=$withval, docbookcatalog=/docbook-ebnf-dtd-missing)
-AC_SUBST(docbookebnfcatalog)
+# Test that Perl has the open/fork feature (Perl 5.8.0 and beyond).
+AC_MSG_CHECKING([whether Perl is recent enough])
+if ! $perl -e 'open(FOO, "-|", "true"); while (<FOO>) { print; }; close FOO or die;'; then
+    AC_MSG_RESULT(no)
+    AC_MSG_ERROR([Your Perl version is too old.  Nix requires Perl 5.8.0 or newer.])
+fi
+AC_MSG_RESULT(yes)
+
+NEED_PROG(cat, cat)
+NEED_PROG(tr, tr)
+AC_ARG_WITH(coreutils-bin, AC_HELP_STRING([--with-coreutils-bin=PATH],
+  [path of cat, mkdir, etc.]),
+  coreutils=$withval, coreutils=$(dirname $cat))
+AC_SUBST(coreutils)
+
+AC_ARG_WITH(docbook-rng, AC_HELP_STRING([--with-docbook-rng=PATH],
+  [path of the DocBook RelaxNG schema]),
+  docbookrng=$withval, docbookrng=/docbook-rng-missing)
+AC_SUBST(docbookrng)

 AC_ARG_WITH(docbook-xsl, AC_HELP_STRING([--with-docbook-xsl=PATH],
  [path of the DocBook XSL stylesheets]),
@@ -95,6 +176,11 @@ AC_ARG_WITH(store-dir, AC_HELP_STRING([--with-store-dir=PATH],
  storedir=$withval, storedir='${prefix}/store')
 AC_SUBST(storedir)

+AC_ARG_WITH(store-state-dir, AC_HELP_STRING([--with-store-state-dir=PATH],
+  [path of the Nix state store]),
+  storestatedir=$withval, storestatedir='${prefix}/state')
+AC_SUBST(storestatedir)
+
 AC_ARG_WITH(bdb, AC_HELP_STRING([--with-bdb=PATH],
  [prefix of Berkeley DB]),
  bdb=$withval, bdb=)
@@ -109,6 +195,18 @@ fi
 AC_SUBST(bdb_lib)
 AC_SUBST(bdb_include)

+AC_ARG_WITH(ext3cow-header, AC_HELP_STRING([--with-ext3cow-header=PATH],
+  [path of the ext3cow header ext3cow_fs.h]),
+  ext3cowheader=$withval, ext3cowheader=)
+AC_SUBST(ext3cowheader)
+AC_CHECK_HEADER(${ext3cowheader})
+
+NEED_PROG(rsync, rsync)
+AC_ARG_WITH(rsync, AC_HELP_STRING([--with-rsync=PATH],
+  [path to the rsync binary.]),
+  rsync=$withval)
+AC_SUBST(rsync)
+
 AC_ARG_WITH(aterm, AC_HELP_STRING([--with-aterm=PATH],
  [prefix of CWI ATerm library]),
  aterm=$withval, aterm=)
@@ -116,20 +214,76 @@ AM_CONDITIONAL(HAVE_ATERM, test -n "$aterm")
 if test -z "$aterm"; then
  aterm_lib='-L${top_builddir}/externals/inst-aterm/lib -lATerm'
  aterm_include='-I${top_builddir}/externals/inst-aterm/include'
+  aterm_bin='${top_builddir}/externals/inst-aterm/bin'
 else
  aterm_lib="-L$aterm/lib -lATerm"
  aterm_include="-I$aterm/include"
+  aterm_bin="$aterm/bin"
 fi
 AC_SUBST(aterm_lib)
 AC_SUBST(aterm_include)
+AC_SUBST(aterm_bin)
+
+AC_ARG_WITH(openssl, AC_HELP_STRING([--with-openssl=PATH],
+  [prefix of the OpenSSL library]),
+  openssl=$withval, openssl=)
+AM_CONDITIONAL(HAVE_OPENSSL, test -n "$openssl")
+if test -n "$openssl"; then
+  LDFLAGS="-L$openssl/lib -lcrypto $LDFLAGS"
+  CFLAGS="-I$openssl/include $CFLAGS"
+  CXXFLAGS="-I$openssl/include $CXXFLAGS"
+  AC_DEFINE(HAVE_OPENSSL, 1, [whether to use OpenSSL])
+fi
+
+AC_ARG_WITH(bzip2, AC_HELP_STRING([--with-bzip2=PATH],
+  [prefix of bzip2]),
+  bzip2=$withval, bzip2=)
+AM_CONDITIONAL(HAVE_BZIP2, test -n "$bzip2")
+if test -z "$bzip2"; then
+  # Headers and libraries will be used from the temporary installation
+  # in externals/inst-bzip2.
+  bzip2_lib='-L${top_builddir}/externals/inst-bzip2/lib -lbz2'
+  bzip2_include='-I${top_builddir}/externals/inst-bzip2/include'
+  # The binary will be copied to $libexecdir.
+  bzip2_bin='${libexecdir}'
+  # But for testing, we have to use the temporary copy :-(
+  bzip2_bin_test='${top_builddir}/externals/inst-bzip2/bin'
+else
+  bzip2_lib="-L$bzip2/lib -lbz2"
+  bzip2_include="-I$bzip2/include"
+  bzip2_bin="$bzip2/bin"
+  bzip2_bin_test="$bzip2/bin"
+fi   
+AC_SUBST(bzip2_lib)
+AC_SUBST(bzip2_include)
+AC_SUBST(bzip2_bin)
+AC_SUBST(bzip2_bin_test)
+

 AC_CHECK_LIB(pthread, pthread_mutex_init)

+
 AC_ARG_ENABLE(init-state, AC_HELP_STRING([--disable-init-state],
  [do not initialise DB etc. in `make install']),
  init_state=$enableval, init_state=yes)
 AM_CONDITIONAL(INIT_STATE, test "$init_state" = "yes")

+
+# Setuid installations.
+AC_CHECK_FUNCS([setresuid setreuid lchown])
+
+
+# Nice to have, but not essential.
+AC_CHECK_FUNCS([strsignal])
+
+
+# This is needed if ATerm, Berkeley DB or bzip2 are static libraries,
+# and the Nix libraries are dynamic.
+if test "$(uname)" = "Darwin"; then
+    LDFLAGS="-all_load $LDFLAGS"
+fi
+
+
 AM_CONFIG_HEADER([config.h])
 AC_CONFIG_FILES([Makefile
   externals/Makefile
@@ -140,19 +294,22 @@ AC_CONFIG_FILES([Makefile
   src/libutil/Makefile
   src/libstore/Makefile
   src/libmain/Makefile
+   src/libext3cow/Makefile
   src/nix-store/Makefile
+   src/nix-state/Makefile
   src/nix-hash/Makefile
   src/libexpr/Makefile
   src/nix-instantiate/Makefile
   src/nix-env/Makefile
-   src/log2xml/Makefile
+   src/nix-worker/Makefile
+   src/nix-setuid-helper/Makefile
+   src/nix-log2xml/Makefile
+   src/bsdiff-4.3/Makefile
   scripts/Makefile
   corepkgs/Makefile
-   corepkgs/fetchurl/Makefile
   corepkgs/nar/Makefile
   corepkgs/buildenv/Makefile
   corepkgs/channels/Makefile
-   corepkgs/nix-pull/Makefile
   doc/Makefile
   doc/manual/Makefile
   misc/Makefile
--- a/corepkgs/Makefile.am
+++ b/corepkgs/Makefile.am
@@ -1 +1 @@
-SUBDIRS = fetchurl nar buildenv channels nix-pull
+SUBDIRS = nar buildenv channels
--- a/corepkgs/buildenv/Makefile.am
+++ b/corepkgs/buildenv/Makefile.am
@@ -3,7 +3,7 @@ all-local: builder.pl
 install-exec-local:
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs/buildenv
-	$(INSTALL_DATA) default.nix $(DESTDIR)$(datadir)/nix/corepkgs/buildenv
+	$(INSTALL_DATA) $(srcdir)/default.nix $(DESTDIR)$(datadir)/nix/corepkgs/buildenv
 	$(INSTALL_PROGRAM) builder.pl $(DESTDIR)$(datadir)/nix/corepkgs/buildenv

 include ../../substitute.mk
--- a/corepkgs/buildenv/builder.pl.in
+++ b/corepkgs/buildenv/builder.pl.in
@@ -3,18 +3,39 @@
 use strict;
 use Cwd;
 use IO::Handle;
+use Fcntl;

 STDOUT->autoflush(1);

 my $out = $ENV{"out"};
 mkdir "$out", 0755 || die "error creating $out";

+sub readlink_or_StateWrapper;
+
+my $symlinks = 0;
+my %path_state_identifier = ();
+
+my %priorities;
+
+my $nixBinDir = $ENV{"nixBinDir"};
+my $nixStore = $ENV{"nixStore"};

 # For each activated package, create symlinks.

 sub createLinks {
    my $srcDir = shift;
+    
+    #Lookup each $stateIdentifiers in $path_state_identifier
+    #we strip $srcDir to its rootdir e.g. /nix/store/......./
+    my @srcDirParts = split /\// , substr($srcDir, length ($nixStore), length ($srcDir));
+    my $srcDirRoot = $nixStore . "/" . $srcDirParts[1];
+	# print "srcDirRoot $srcDirRoot \n";
+    
    my $dstDir = shift;
+    my $priority = shift;
+	my $pkgStateIdentifier = $path_state_identifier{$srcDirRoot};		# We have to look it up each time since recursion can change the $srcDir, but not the identifier
+
+	#print "createLinks $srcDir to $dstDir with iden $pkgStateIdentifier \n";

    my @srcFiles = glob("$srcDir/*");

@@ -22,19 +43,24 @@ sub createLinks {
        my $baseName = $srcFile;
        $baseName =~ s/^.*\///g; # strip directory
        my $dstFile = "$dstDir/$baseName";
-        
-	if ($srcFile =~ /\/propagated-build-inputs$/ ||
-            $srcFile =~ /\/nix-support$/)
+
+    	# Urgh, hacky...
+		if ($srcFile =~ /\/propagated-build-inputs$/ ||
+            $srcFile =~ /\/nix-support$/ ||
+            $srcFile =~ /\/perllocal.pod$/ ||
+            $srcFile =~ /\/info\/dir$/ ||
+            $srcFile =~ /\/log$/)
        {
-            # Do noting.
-	}
+            # Do nothing.
+		}

        elsif (-d $srcFile) {

            lstat $dstFile;
            
+            #go recursive on directorys
            if (-d _) {
-                createLinks($srcFile, $dstFile);
+                createLinks($srcFile, $dstFile, $priority);
            }

            elsif (-l _) {
@@ -43,51 +69,183 @@ sub createLinks {
                    die "collission between directory `$srcFile' and non-directory `$target'";
                }
                unlink $dstFile or die "error unlinking `$dstFile': $!";
-                mkdir $dstFile, 0755 || 
-                    die "error creating directory `$dstFile': $!";
-                createLinks($target, $dstFile);
-                createLinks($srcFile, $dstFile);
+                mkdir $dstFile, 0755 || die "error creating directory `$dstFile': $!";
+                createLinks($target, $dstFile, $priorities{$dstFile});
+                createLinks($srcFile, $dstFile, $priority);
            }

            else {
+                
+                #print "1ST DIR LINK $srcFile to $dstFile with iden $pkgStateIdentifier \n";
+                
                symlink($srcFile, $dstFile) ||
                    die "error creating link `$dstFile': $!";
+                $priorities{$dstFile} = $priority;
+                $symlinks++;
            }
        }

-        elsif (-l $dstFile) {
-            my $target = readlink $dstFile;
-            die "collission between `$srcFile' and `$target'";
-        }
-
        else {
-#            print "linking $dstFile to $srcFile\n";
-            symlink($srcFile, $dstFile) ||
-                die "error creating link `$dstFile': $!";
-        }
+
+			# print "ELSE LINK $srcFile to $dstFile with iden $pkgStateIdentifier \n";
+
+			# if we have a state component with a identifier different then ""
+			if($pkgStateIdentifier ne "__NOSTATE__" && $pkgStateIdentifier ne ""){
+	            
+	            my @pathparts = split /\// , $srcFile;
+	            my $parentDir = $pathparts[scalar(@pathparts) - 2];
+	            
+	            if( $parentDir eq "bin" || $parentDir eq "sbin"){		#hacky....
+		            
+		            print "STATELINK $srcFile to $dstFile - $pkgStateIdentifier \n";
+		            
+		            my $new_dstFile;
+		            my $new_stateIdentifier;		            
+		            if($pkgStateIdentifier eq "__EMTPY__"){
+		            	$new_dstFile = $dstFile;
+		            	$new_stateIdentifier = "";
+		            }
+		            else{
+		            	$new_dstFile = "$dstFile-$pkgStateIdentifier";
+		            	$new_stateIdentifier = $pkgStateIdentifier;
+		            }
+		            
+		            # We also check with -e if the wrapperscript-file exists, and if is it a symlink (with -l)
+		            if (-l $new_dstFile || -e $new_dstFile) {
+			                my $target = readlink_or_StateWrapper $new_dstFile;
+			                die "(state) collission between `$srcFile' and `$target' (over $new_dstFile)";
+			        }
+		            
+		            sysopen (DSTFILEHANDLE, $new_dstFile, O_RDWR|O_EXCL|O_CREAT, 0755);
+					printf DSTFILEHANDLE "#! @shell@ \n";
+					printf DSTFILEHANDLE "$nixBinDir/nix-state --run --identifier=$new_stateIdentifier $srcFile \"\$@\" \n"; 
+					close (DSTFILEHANDLE);
+	            }
+	            
+			}
+			elsif($pkgStateIdentifier ne "__NOSTATE__" && $pkgStateIdentifier eq ""){		#TODO we now dont create symlinks for state packages with a empty identifier
+																							#TODO but we must do it if there is no normal non-state pacakge
+			}
+			
+	        else {
+
+	            if (-l $dstFile || -e $dstFile) {
+	                my $target = readlink_or_StateWrapper $dstFile;
+	                my $prevPriority = $priorities{$dstFile};
+	                die ( "Collission between `$srcFile' and `$target'. "
+	                    . "Suggested solution: use `nix-env --set-flag "
+	                    . "priority NUMBER PKGNAME' to change the priority of "
+	                    . "one of the conflicting packages.\n" )
+	                    if $prevPriority == $priority;
+	                next if $prevPriority < $priority;
+	                unlink $dstFile or die;
+	            }
+	
+				# print "2ND LINK $srcFile to $dstFile with iden $pkgStateIdentifier \n";
+	            symlink($srcFile, $dstFile) ||
+	                die "error creating link `$dstFile': $!";
+	            $priorities{$dstFile} = $priority;
+	            $symlinks++;
+	        }
+		}
    }
 }


 my %done;
+my %postponed;

+sub addPkg;
 sub addPkg {
    my $pkgDir = shift;
+    my $priority = shift;

    return if (defined $done{$pkgDir});
    $done{$pkgDir} = 1;

-    createLinks("$pkgDir", "$out");
+#    print "symlinking $pkgDir\n";
+    createLinks("$pkgDir", "$out", $priority);
+
+    my $propagatedFN = "$pkgDir/nix-support/propagated-user-env-packages";
+    if (-e $propagatedFN) {
+        open PROP, "<$propagatedFN" or die;
+        my $propagated = <PROP>;
+        close PROP;
+        my @propagated = split ' ', $propagated;
+        foreach my $p (@propagated) {
+            $postponed{$p} = 1 unless defined $done{$p};
+        }
+    }
+}
+
+sub readlink_or_StateWrapper {
+
+	my $src = shift;
+	my $target;
+
+    if (-l $src)
+    {   $target = readlink $src;    }
+    else{
+    	open(DAT, $src) || die("Could not open file!");
+        my @raw_data=<DAT>;
+        close(DAT);
+        $target = $raw_data[1];
+    }
+    return $target
+}
+
+my @stateIdentifiers = split ' ', $ENV{"stateIdentifiers"};
+my $si_counter = 0;
+
+# Convert the stuff we get from the environment back into a coherent
+# data type.
+my @paths = split ' ', $ENV{"paths"};
+my @active = split ' ', $ENV{"active"};
+my @priority = split ' ', $ENV{"priority"};
+
+die if scalar @paths != scalar @active;
+die if scalar @paths != scalar @priority;
+
+my %pkgs;
+
+for (my $n = 0; $n < scalar @paths; $n++) {
+    $pkgs{$paths[$n]} =
+        { active => $active[$n]
+        , priority => $priority[$n] 
+        , stateidentifier => $stateIdentifiers[$n]
+        };
+        
+    $path_state_identifier{$paths[$n]} = $stateIdentifiers[$n];
+}
+
+# Symlink to the packages that have been installed explicitly by the
+# user.
+foreach my $pkg (sort (keys %pkgs)) {
+
+	#print "SP: $pkg \n";
+	#print "SI: $pkgs{$pkg}->{stateidentifier} \n";
+    #print "PR: $pkgs{$pkg}->{priority} \n";	
+    
+    addPkg($pkg, $pkgs{$pkg}->{priority}) if $pkgs{$pkg}->{active} ne "false";
+    $si_counter++;
 }


-my @args = split ' ', $ENV{"derivations"};
-
-while (scalar @args > 0) {
-    my $drvPath = shift @args;
-    print "adding $drvPath\n";
-    addPkg($drvPath);
+# Symlink to the packages that have been "propagated" by packages
+# installed by the user (i.e., package X declares that it want Y
+# installed as well).  We do these later because they have a lower
+# priority in case of collisions.
+my $priorityCounter = 1000; # don't care about collisions
+while (scalar(keys %postponed) > 0) {
+    
+    my @pkgDirs = keys %postponed;
+    %postponed = ();
+    foreach my $pkgDir (sort @pkgDirs) {
+        addPkg($pkgDir, $priorityCounter++);
+    }
 }

+print STDERR "created $symlinks symlinks in user environment\n";

 symlink($ENV{"manifest"}, "$out/manifest") or die "cannot create manifest";
+
--- a/corepkgs/buildenv/default.nix
+++ b/corepkgs/buildenv/default.nix
@@ -1,9 +1,16 @@
-{system, derivations, manifest}:
+{system, derivations, stateIdentifiers, manifest, nixBinDir, nixStore}:

 derivation { 
  name = "user-environment";
  system = system;
  builder = ./builder.pl;
-  derivations = derivations;
+  
+  stateIdentifiers = stateIdentifiers;
  manifest = manifest;
+  inherit nixBinDir nixStore;
+
+  # !!! grmbl, need structured data for passing this in a clean way.
+  paths = derivations;
+  active = map (x: if x ? meta && x.meta ? active then x.meta.active else "true") derivations;
+  priority = map (x: if x ? meta && x.meta ? priority then x.meta.priority else "5") derivations;
 }
--- a/corepkgs/channels/Makefile.am
+++ b/corepkgs/channels/Makefile.am
@@ -3,7 +3,7 @@ all-local: unpack.sh
 install-exec-local:
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs/channels
-	$(INSTALL_DATA) unpack.nix $(DESTDIR)$(datadir)/nix/corepkgs/channels
+	$(INSTALL_DATA) $(srcdir)/unpack.nix $(DESTDIR)$(datadir)/nix/corepkgs/channels
 	$(INSTALL_PROGRAM) unpack.sh $(DESTDIR)$(datadir)/nix/corepkgs/channels

 include ../../substitute.mk
--- a/corepkgs/channels/unpack.sh.in
+++ b/corepkgs/channels/unpack.sh.in
@@ -1,24 +1,26 @@
 #! @shell@ -e

-export PATH=/bin:/usr/bin # !!! impure
-
-mkdir $out
-mkdir $out/tmp
+@coreutils@/mkdir $out
+@coreutils@/mkdir $out/tmp
 cd $out/tmp

-expr=$out/default.nix
-echo '[' > $expr
+inputs=($inputs)
+for ((n = 0; n < ${#inputs[*]}; n += 2)); do
+    channelName=${inputs[n]}
+    channelTarball=${inputs[n+1]}
+    echo "unpacking channel $channelName"
+    @bunzip2@ < $channelTarball | @tar@ xf -

-nr=0
-for i in $inputs; do
-    echo "unpacking $i"
-    @bunzip2@ < $i | tar xvf -
-    mv * ../$nr # !!! hacky
-    echo "(import ./$nr)" >> $expr
-    nr=$(($nr + 1))
+    nr=1
+    attrName=$(echo $channelName | @tr@ -- '- ' '__')
+    dirName=$attrName
+    while test -e ../$dirName; do
+        nr=$((nr+1))
+        dirName=$attrName-$nr
+    done
+
+    @coreutils@/mv * ../$dirName # !!! hacky
 done

-echo ']' >> $expr
-
 cd ..
-rmdir tmp
+@coreutils@/rmdir tmp
--- a/corepkgs/fetchurl/Makefile.am
+++ b/corepkgs/fetchurl/Makefile.am
@@ -1,11 +0,0 @@
-all-local: builder.sh
-
-install-exec-local:
-	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs
-	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs/fetchurl
-	$(INSTALL_DATA) default.nix $(DESTDIR)$(datadir)/nix/corepkgs/fetchurl
-	$(INSTALL_PROGRAM) builder.sh $(DESTDIR)$(datadir)/nix/corepkgs/fetchurl
-
-include ../../substitute.mk
-
-EXTRA_DIST = default.nix builder.sh.in
--- a/corepkgs/fetchurl/builder.sh.in
+++ b/corepkgs/fetchurl/builder.sh.in
@@ -1,19 +0,0 @@
-#! @shell@ -e
-
-export PATH=/bin:/usr/bin
-
-echo "downloading $url into $out"
-
-prefetch=@storedir@/nix-prefetch-url-$md5
-if test -f "$prefetch"; then
-    echo "using prefetched $prefetch";
-    mv $prefetch $out
-else
-    @curl@ --fail --location --max-redirs 20 "$url" > "$out"
-fi
-
-actual=$(@bindir@/nix-hash --flat $out)
-if test "$actual" != "$md5"; then
-    echo "hash is $actual, expected $md5"
-    exit 1
-fi
--- a/corepkgs/fetchurl/default.nix
+++ b/corepkgs/fetchurl/default.nix
@@ -1,8 +0,0 @@
-{system, url, md5}:
-
-derivation {
-  name = baseNameOf (toString url);
-  builder = ./builder.sh;
-  id = md5;
-  inherit system url md5;
-}
--- a/corepkgs/nar/Makefile.am
+++ b/corepkgs/nar/Makefile.am
@@ -1,13 +1,11 @@
-all-local: nar.sh unnar.sh
+all-local: nar.sh

 install-exec-local:
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs/nar
-	$(INSTALL_DATA) nar.nix $(DESTDIR)$(datadir)/nix/corepkgs/nar
+	$(INSTALL_DATA) $(srcdir)/nar.nix $(DESTDIR)$(datadir)/nix/corepkgs/nar
 	$(INSTALL_PROGRAM) nar.sh $(DESTDIR)$(datadir)/nix/corepkgs/nar
-	$(INSTALL_DATA) unnar.nix $(DESTDIR)$(datadir)/nix/corepkgs/nar
-	$(INSTALL_PROGRAM) unnar.sh $(DESTDIR)$(datadir)/nix/corepkgs/nar

 include ../../substitute.mk

-EXTRA_DIST = nar.nix nar.sh.in unnar.nix unnar.sh.in
+EXTRA_DIST = nar.nix nar.sh.in
--- a/corepkgs/nar/nar.nix
+++ b/corepkgs/nar/nar.nix
@@ -1,6 +1,7 @@
-{system, path}: derivation {
+{system, storePath, hashAlgo}: 
+
+derivation {
  name = "nar";
  builder = ./nar.sh;
-  system = system;
-  path = path;
+  inherit system storePath hashAlgo;
 }
--- a/corepkgs/nar/nar.sh.in
+++ b/corepkgs/nar/nar.sh.in
@@ -1,13 +1,14 @@
 #! @shell@ -e

-# !!! impure; fix this
-export PATH=/bin:/usr/bin
+echo "packing $storePath into $out..."
+@coreutils@/mkdir $out
+dst=$out/tmp.nar.bz2
+@bindir@/nix-store --dump "$storePath" > tmp

-echo "packing $path into $out..."
-mkdir $out
-dst=$out/$(basename $path).nar.bz2
-@bindir@/nix-store --dump "$path" | @bzip2@ > $dst
+@bzip2@ < tmp > $dst

-md5=$(md5sum -b $dst | cut -c1-32)
-if test $? != 0; then exit 1; fi
-echo $md5 > $out/md5
+@bindir@/nix-hash -vvvvv --flat --type $hashAlgo --base32 tmp > $out/nar-hash
+
+@bindir@/nix-hash --flat --type $hashAlgo --base32 $dst > $out/narbz2-hash
+
+@coreutils@/mv $out/tmp.nar.bz2 $out/$(@coreutils@/cat $out/narbz2-hash).nar.bz2
--- a/corepkgs/nar/unnar.nix
+++ b/corepkgs/nar/unnar.nix
@@ -1,7 +0,0 @@
-{system, narFile, outPath}: derivation {
-  name = "unnar";
-  builder = ./unnar.sh;
-  system = system;
-  narFile = narFile;
-  outPath = outPath;
-}
--- a/corepkgs/nar/unnar.sh.in
+++ b/corepkgs/nar/unnar.sh.in
@@ -1,4 +0,0 @@
-#! @shell@ -e
-
-echo "unpacking $narFile to $out..."
-@bunzip2@ < $narFile | @bindir@/nix-store --restore "$out"
--- a/corepkgs/nix-pull/Makefile.am
+++ b/corepkgs/nix-pull/Makefile.am
@@ -1,11 +0,0 @@
-all-local: builder.sh
-
-install-exec-local:
-	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs
-	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/corepkgs/nix-pull
-	$(INSTALL_DATA) default.nix $(DESTDIR)$(datadir)/nix/corepkgs/nix-pull
-	$(INSTALL_PROGRAM) builder.sh $(DESTDIR)$(datadir)/nix/corepkgs/nix-pull
-
-include ../../substitute.mk
-
-EXTRA_DIST = default.nix builder.sh.in
--- a/corepkgs/nix-pull/builder.sh.in
+++ b/corepkgs/nix-pull/builder.sh.in
@@ -1,34 +0,0 @@
-#! @shell@ -e
-
-export PATH=/bin:/usr/bin
-
-mkdir $out
-
-cat > $out/fetch <<EOF
-#! @shell@ -e
-
-export PATH=/bin:/usr/bin
-
-echo "downloading \$2..."
-
-export PRINT_PATH=1
-result=(\$(@bindir@/nix-prefetch-url \$2))
-
-hash=\${result[0]}
-path=\${result[1]}
-
-if test "\$hash" != "\$3"; then
-    echo "hash is \$hash, expected \$3"
-    exit 1
-fi
-
-echo "unpacking into \$1..."
-
-if ! @bunzip2@ < "\$path" | @bindir@/nix-store --restore "\$1"; then
-    exit 1
-fi
-
-exit 0
-EOF
-
-chmod +x $out/fetch
--- a/corepkgs/nix-pull/default.nix
+++ b/corepkgs/nix-pull/default.nix
@@ -1,7 +0,0 @@
-{system}:
-
-derivation {
-  name = "nix-pull";
-  builder = ./builder.sh;
-  inherit system;
-}
--- a/createRelease.sh
+++ b/createRelease.sh
@@ -0,0 +1,21 @@
+#! /bin/sh -e
+
+dir1=releases
+dir2=nix-state
+mkdir -p $dir1
+cd $dir1
+rm -rf $dir2
+mkdir -p $dir2
+cd $dir2
+svn co https://svn.cs.uu.nl:12443/repos/trace/nix/branches/state ./
+revision=`svn info | grep ^Revision | sed 's/Revision: //g'`
+cd ..
+date=`date +%Y%m%d`
+tarfile=snix-${date}-rev${revision}.tar.gz
+tar -cvf $tarfile \
+    --preserve-permissions \
+    --atime-preserve \
+    --gzip \
+    --verbose \
+    --no-ignore-command-error \
+    $dir2/
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -1 +1 @@
-SUBDIRS = manual
+SUBDIRS = 
--- a/doc/dev/release-procedures.txt
+++ b/doc/dev/release-procedures.txt
@@ -1,5 +1,8 @@
 To produce a `stable' release from the trunk:

+-1. Update the release notes; make sure that the release date is
+    correct.
+
 0. Make sure that the trunk builds in the release supervisor.

 1. Branch the trunk, e.g., `svn cp .../trunk
@@ -22,8 +25,8 @@ To produce a `stable' release from the trunk:
   branch (e.g., `.../branches/0.5') should be created from the
   original revision of the trunk (since maintenance releases should
   also be tested first; hence, we cannot have `STABLE=1').  The same
-   procedure can then be followed to produce maintenance release; just
-   substitute `.../branches/VERSION' for the trunk.
+   procedure can then be followed to produce maintenance releases;
+   just substitute `.../branches/VERSION' for the trunk.

 7. Switch back to the trunk.

--- a/doc/manual/Makefile.am
+++ b/doc/manual/Makefile.am
@@ -1,50 +1,97 @@
-ENV = SGML_CATALOG_FILES=$(docbookcatalog):$(docbookebnfcatalog)
-
-XMLLINT = $(ENV) $(xmllint) $(xmlflags) --catalogs
-XSLTPROC = $(ENV) $(xsltproc) $(xmlflags) --catalogs \
+XMLLINT = $(xmllint) $(xmlflags)
+XSLTPROC = $(xsltproc) $(xmlflags) \
 --param section.autolabel 1 \
 --param section.label.includes.component.label 1 \
- --param html.stylesheet \'style.css\'
+ --param html.stylesheet \'style.css\' \
+ --param xref.with.number.and.title 1 \
+ --param toc.section.depth 3 \
+ --param admon.style \'\' \
+ --param callout.graphics.extension \'.gif\'

-man1_MANS = nix-env.1 nix-store.1 nix-instantiate.1 \
+# Note: we use GIF for now, since the PNGs shipped with Docbook aren't
+# transparent.
+
+man1_MANS = nix-env.1 nix-build.1 nix-store.1 nix-instantiate.1 \
 nix-collect-garbage.1 nix-push.1 nix-pull.1 \
- nix-prefetch-url.1
+ nix-prefetch-url.1 nix-channel.1 \
+ nix-pack-closure.1 nix-unpack-closure.1 \
+ nix-install-package.1 nix-hash.1 nix-copy-closure.1

-SOURCES = manual.xml introduction.xml installation.xml overview.xml \
+FIGURES = figures/user-environments.png
+
+MANUAL_SRCS = manual.xml introduction.xml installation.xml \
+ package-management.xml writing-nix-expressions.xml builtins.xml \
+ build-farm.xml \
 $(man1_MANS:.1=.xml) \
 troubleshooting.xml bugs.xml opt-common.xml opt-common-syn.xml \
- quick-start.xml nix-lang-ref.xml style.css images
+ env-common.xml quick-start.xml nix-lang-ref.xml glossary.xml \
+ conf-file.xml release-notes.xml \
+ style.css images

-manual.is-valid: $(SOURCES) version.xml
-	$(XMLLINT) --noout --valid manual.xml
+manual.is-valid: $(MANUAL_SRCS) version.txt
+#	$(XMLLINT) --xinclude $< | $(XMLLINT) --noout --nonet --relaxng $(docbookrng)/docbook.rng -
+	if test "$(jing)" != "false"; then \
+		$(XMLLINT) --xinclude $< | $(jing) $(docbookrng)/docbook.rng /dev/fd/0; \
+	else \
+		echo "Not validating."; \
+	fi
 	touch $@

-version.xml:
-	echo -n $(VERSION) > version.xml
+version.txt:
+	echo -n $(VERSION) > version.txt

-man $(MANS): $(SOURCES) manual.is-valid
-	$(XSLTPROC) $(docbookxsl)/manpages/docbook.xsl manual.xml
+man $(MANS): $(MANUAL_SRCS) manual.is-valid
+	$(XSLTPROC) --nonet --xinclude $(docbookxsl)/manpages/docbook.xsl manual.xml

-manual.html: $(SOURCES) manual.is-valid images
-	$(XSLTPROC) --output manual.html $(docbookxsl)/html/docbook.xsl manual.xml
+manual.html: $(MANUAL_SRCS) manual.is-valid images
+	$(XSLTPROC) --nonet --xinclude --output manual.html \
+	  $(docbookxsl)/html/docbook.xsl manual.xml

-all-local: manual.html
+manual.pdf: $(MANUAL_SRCS) manual.is-valid images
+	if test "$(dblatex)" != ""; then \
+		$(dblatex) manual.xml; \
+	else \
+		echo "Please install dblatex and rerun configure."; \
+		exit 1; \
+	fi
+
+
+NEWS_OPTS = \
+ --stringparam generate.toc "article nop" \
+ --stringparam section.autolabel.max.depth 0 \
+ --stringparam header.rule 0
+
+NEWS.html: release-notes.xml
+	$(XSLTPROC) --nonet --xinclude --output $@ $(NEWS_OPTS) \
+	  $(docbookxsl)/html/docbook.xsl release-notes.xml
+
+NEWS.txt: release-notes.xml
+	$(XSLTPROC) --nonet --xinclude quote-literals.xsl release-notes.xml | \
+	  $(XSLTPROC) --nonet --output $@.tmp.html $(NEWS_OPTS) \
+	  $(docbookxsl)/html/docbook.xsl -
+	LANG=en_US $(w3m) -dump $@.tmp.html > $@
+	rm $@.tmp.html
+
+
+all-local: manual.html NEWS.html NEWS.txt

 install-data-local: manual.html
 	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/manual
 	$(INSTALL_DATA) manual.html $(DESTDIR)$(datadir)/nix/manual
 	$(INSTALL_DATA) style.css $(DESTDIR)$(datadir)/nix/manual
 	cp -r images $(DESTDIR)$(datadir)/nix/manual/images
+	$(INSTALL) -d $(DESTDIR)$(datadir)/nix/manual/figures
+	$(INSTALL_DATA) $(FIGURES) $(DESTDIR)$(datadir)/nix/manual/figures

 images:
 	mkdir images
-	cp $(docbookxsl)/images/*.png images
+#	cp $(docbookxsl)/images/*.gif images
 	mkdir images/callouts
-	cp $(docbookxsl)/images/callouts/*.png images/callouts
-	chmod +w -R images
+	cp $(docbookxsl)/images/callouts/*.gif images/callouts
+	chmod -R +w images

-KEEP = manual.html manual.is-valid version.xml $(MANS)
+KEEP = manual.html manual.is-valid version.txt $(MANS) NEWS.html NEWS.txt

-EXTRA_DIST = $(SOURCES) $(KEEP)
+EXTRA_DIST = $(MANUAL_SRCS) $(FIGURES) $(KEEP)

 DISTCLEANFILES = $(KEEP)
--- a/doc/manual/NEWS.txt
+++ b/doc/manual/NEWS.txt
@@ -0,0 +1 @@
+New state nix version by wouter ...
--- a/doc/manual/bugs.xml
+++ b/doc/manual/bugs.xml
@@ -1,115 +1,39 @@
-<appendix>
-  <title>Bugs / To-Do</title>
+<appendix xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink">

-  <itemizedlist>
+<title>Bugs / To-Do</title>

-    <listitem>
-      <para>
-        The man-pages generated from the DocBook documentation are ugly.
-      </para>
-    </listitem>

-    <listitem>
-      <para>
-        Generations properly form a tree.  E.g., if after switching to
-        generation 39, we perform an installation action, a generation
-        43 is created which is a descendant of 39, not 42.  So a
-        rollback from 43 ought to go back to 39.  This is not
-        currently implemented; generations form a linear sequence.
-      </para>
-    </listitem>
+<itemizedlist>

-    <listitem>
-      <para>
-        Unify the concepts of successors and substitutes into a
-        general notion of <emphasis>equivalent expressions</emphasis>.
-        Expressions are equivalent if they have the same target paths
-        with the same identifiers.  However, even though they are
-        functionally equivalent, they may differ stronly with respect
-        to their <emphasis>performance characteristics</emphasis>.
-        For example, realising a closure expression is more efficient
-        that realising the derivation expression from which it was
-        produced.  On the other hand, distributing sources may be more
-        efficient (storage- or bandwidth-wise) than distributing
-        binaries.  So we need to be able to attach weigths or
-        priorities or performance annotations to expressions; Nix can
-        then choose the most efficient expression dependent on the
-        context.
-      </para>
-    </listitem>
+<listitem><para>The man-pages generated from the DocBook documentation
+are ugly.</para></listitem>

-    <listitem>
-      <para>
-        <emphasis>Build management.</emphasis>  In principle it is already
-        possible to do build management using Nix (by writing builders that
-        perform appropriate build steps), but the Nix expression language is
-        not yet powerful enough to make this pleasant (?).  The language should
-        be extended with features from the <ulink
-          url='http://www.cs.uu.nl/~eelco/maak/'>Maak build manager</ulink>.
-        Another interesting idea is to write a <command>make</command>
-        implementation that uses Nix as a back-end to support <ulink
-          url='http://www.research.att.com/~bs/bs_faq.html#legacy'>legacy</ulink> 
-        build files.
-      </para>
-    </listitem>
+<listitem><para>Generations properly form a tree.  E.g., if after
+switching to generation 39, we perform an installation action, a
+generation 43 is created which is a descendant of 39, not 42.  So a
+rollback from 43 ought to go back to 39.  This is not currently
+implemented; generations form a linear sequence.</para></listitem>

-    <listitem>
-      <para>
-        The current garbage collector is a hack.  It should be
-        integrated into <command>nix-store</command>.  It should
-        delete derivations in an order determined by topologically
-        sorting derivations under the points-to relation.  This
-        ensures that no store paths ever exist that point to
-        non-existant store paths.
-      </para>
-    </listitem>
+<listitem><para>For security, <command>nix-push</command> manifests
+should be digitally signed, and <command>nix-pull</command> should
+verify the signatures.  The actual NAR archives in the cache do not
+need to be signed, since the manifest contains cryptographic hashes of
+these files (and <filename>fetchurl.nix</filename> checks
+them).</para></listitem>

-    <listitem>
-      <para>
-        There are race conditions between the garbage collector and
-        other Nix tools.  For instance, when we run
-        <command>nix-env</command> to build and install a derivation
-        and run the garbage collector at the same time, the garbage
-        collector may kick in exactly between the build and
-        installation steps, i.e., before the newly built derivation
-        has become reachable from a root of the garbage collector.
-      </para>
+<listitem><para>It would be useful to have an option in
+<command>nix-env --delete-generations</command> to remove non-current
+generations older than a certain age.</para></listitem>

-      <para>
-        One solution would be for these programs to properly register
-        temporary roots for the collector.  Another would be to use
-        stop-the-world garbage collection: if any tool is running, the
-        garbage collector blocks, and vice versa.  These solutions do
-        not solve the situation where multiple tools are involved,
-        e.g.,
+<listitem><para>There should be a flexible way to change the user
+environment builder.  Currently, you have to replace
+<filename><replaceable>prefix</replaceable>/share/nix/corepkgs/buildenv/builder.pl</filename>,
+which is hard-coded into <command>nix-env</command>.  Also, the
+default builder should be more powerful.  For instance, there should
+be some way to specify priorities to resolve
+collisions.</para></listitem>

-        <screen>
-$ nix-store -r $(nix-instantiate foo.nix)</screen>
-
-        since even if <command>nix-instantiate</command> where to
-        register a temporary root, it would be released by the time
-        <command>nix-store</command> is started.  A solution would be
-        to write the intermediate value to a file that is used as a
-        root to the collector, e.g.,
-        
-        <screen>
-$ nix-instantiate foo.nix > /nix/var/nix/roots/bla
-$ nix-store -r $(cat /nix/var/nix/roots/bla)</screen>
-
-      </para>
-    </listitem>
-
-    <listitem>
-      <para>
-        For security, <command>nix-push</command> manifests should be
-        digitally signed, and <command>nix-pull</command> should
-        verify the signatures.  The actual NAR archives in the cache
-        do not need to be signed, since the manifest contains
-        cryptographic hashes of these files (and
-        <filename>fetchurl.nix</filename> checks them).
-      </para>
-    </listitem>
-
-  </itemizedlist>
+</itemizedlist>

 </appendix>
--- a/doc/manual/build-farm.xml
+++ b/doc/manual/build-farm.xml
@@ -0,0 +1,137 @@
+<chapter xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id='chap-build-farm'>
+
+<title>Setting up a Build Farm</title>
+
+
+<para>This chapter provides some sketchy information on how to set up
+a Nix-based build farm.  Nix is particularly suited as a basis for a
+build farm, since:
+
+<itemizedlist>
+
+  <listitem><para>Nix supports distributed builds: a local Nix
+  installation can forward Nix builds to other machines over the
+  network.  This allows multiple builds to be performed in parallel
+  (thus improving performance), but more in importantly, it allows Nix
+  to perform multi-platform builds in a semi-transparent way.  For
+  instance, if you perform a build for a
+  <literal>powerpc-darwin</literal> on an
+  <literal>i686-linux</literal> machine, Nix can automatically forward
+  the build to a <literal>powerpc-darwin</literal> machine, if
+  available.</para></listitem>
+
+  <listitem><para>The Nix expression language is ideal for describing
+  build jobs, plus all their dependencies.  For instance, if your
+  package has some dependency, you don't have to manually install it
+  on all the machines in the build farm; they will be built
+  automatically.</para></listitem>
+
+  <listitem><para>Proper release management requires that builds (if
+  deployed) are traceable: it should be possible to figure out from
+  exactly what sources they were built, in what configuration, etc.;
+  and it should be possible to reproduce the build, if necessary.  Nix
+  makes this possible since Nix's hashing scheme uniquely identifies
+  builds, and Nix expressions are self-contained.</para></listitem>
+
+  <listitem><para>Nix will only rebuild things that have actually
+  changed.  For instance, if the sources of a package haven't changed
+  between runs of the build farm, the package won't be rebuilt (unless
+  it was garbage-collected).  Also, dependencies typically don't
+  change very often, so they only need to be built
+  once.</para></listitem>
+
+  <listitem><para>The results of a Nix build farm can be made
+  available through a channel, so successful builds can be deployed to
+  users immediately.</para></listitem>
+
+</itemizedlist>
+
+</para>
+
+
+<section><title>Overview</title>
+
+<para>TODO</para>
+
+<para>The sources of the Nix build farm are at <link
+xlink:href='https://svn.cs.uu.nl:12443/repos/trace/release/trunk'/>.</para>
+
+</section>
+
+
+<section xml:id='sec-distributed-builds'><title>Setting up distributed builds</title>
+
+<para>You can enable distributed builds by setting the environment
+variable <envar>NIX_BUILD_HOOK</envar> to point to a program that Nix
+will call whenever it wants to build a derivation.  The build hook
+(typically a shell or Perl script) can decline the build, in which Nix
+will perform it in the usual way if possible, or it can accept it, in
+which case it is responsible for somehow getting the inputs of the
+build to another machine, doing the build there, and getting the
+results back.  The details of the build hook protocol are described in
+the documentation of the <link
+linkend="envar-build-hook"><envar>NIX_BUILD_HOOK</envar>
+variable</link>.</para>
+
+<example xml:id='ex-remote-systems'><title>Remote machine configuration:
+<filename>remote-systems.conf</filename></title>
+<programlisting>
+nix@mcflurry.labs.cs.uu.nl  powerpc-darwin  /home/nix/.ssh/id_quarterpounder_auto  2
+nix@scratchy.labs.cs.uu.nl  i686-linux      /home/nix/.ssh/id_scratchy_auto        1
+</programlisting>
+</example>
+
+<para>An example build hook can be found in the Nix build farm
+sources: <link
+xlink:href='https://svn.cs.uu.nl:12443/repos/trace/release/trunk/common/distributed/build-remote.pl'
+/>.  It should be suitable for most purposes, with maybe some minor
+adjustments.  It uses <command>ssh</command> and
+<command>rsync</command> to copy the build inputs and outputs and
+perform the remote build.  You should define a list of available build
+machines and set the environment variable
+<envar>REMOTE_SYSTEMS</envar> to point to it.  An example
+configuration is shown in <xref linkend='ex-remote-systems' />.  Each
+line in the file specifies a machine, with the following bits of
+information:
+
+<orderedlist>
+  
+  <listitem><para>The name of the remote machine, with optionally the
+  user under which the remote build should be performed.  This is
+  actually passed as an argument to <command>ssh</command>, so it can
+  be an alias defined in your
+  <filename>~/.ssh/config</filename>.</para></listitem>
+
+  <listitem><para>The Nix platform type identifier, such as
+  <literal>powerpc-darwin</literal>.</para></listitem>
+
+  <listitem><para>The SSH private key to be used to log in to the
+  remote machine.  Since builds should be non-interactive, this key
+  should not have a passphrase!</para></listitem>
+
+  <listitem><para>The maximum <quote>load</quote> of the remote
+  machine.  This is just the maximum number of jobs that
+  <filename>build-remote.pl</filename> will execute in parallel on the
+  machine.  Typically this should be equal to the number of
+  CPUs.</para></listitem>
+
+</orderedlist>
+
+You should also set up the environment variable
+<envar>CURRENT_LOAD</envar> to point at a file that
+<filename>build-remote.pl</filename> uses to remember how many jobs it
+is currently executing remotely.  It doesn't look at the actual load
+on the remote machine, so if you have multiple instances of Nix
+running, they should use the same <envar>CURRENT_LOAD</envar>
+file<footnote><para>Although there are probably some race conditions
+in the script right now.</para></footnote>.  Maybe in the future
+<filename>build-remote.pl</filename> will look at the actual remote
+load.  The load file should exist, so you should just create it as an
+empty file initially.</para>
+  
+</section>
+
+
+</chapter>
--- a/doc/manual/builtins.xml
+++ b/doc/manual/builtins.xml
@@ -0,0 +1,760 @@
+<section xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id='ssec-builtins'>
+
+<title>Built-in functions</title>
+
+
+<para>This section lists the functions and constants built into the
+Nix expression evaluator.  (The built-in function
+<function>derivation</function> is discussed above.)  Some built-ins,
+such as <function>derivation</function>, are always in scope of every
+Nix expression; you can just access them right away.  But to prevent
+polluting the namespace too much, most built-ins are not in scope.
+Instead, you can access them through the <varname>builtins</varname>
+built-in value, which is an attribute set that contains all built-in
+functions and values.  For instance, <function>derivation</function>
+is also available as <function>builtins.derivation</function>.</para>
+
+
+<variablelist>
+
+  
+  <varlistentry><term><function>abort</function> <replaceable>s</replaceable></term>
+
+    <listitem><para>Abort Nix expression evaluation, print error
+    message <replaceable>s</replaceable>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.add</function>
+  <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
+
+    <listitem><para>Return the sum of the integers
+    <replaceable>e1</replaceable> and
+    <replaceable>e2</replaceable>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.attrNames</function>
+  <replaceable>attrs</replaceable></term>
+
+    <listitem><para>Return the names of the attributes in the
+    attribute set <replaceable>attrs</replaceable> in a sorted list.
+    For instance, <literal>builtins.attrNames {y = 1; x =
+    "foo";}</literal> evaluates to <literal>["x" "y"]</literal>.
+    There is no built-in function <function>attrValues</function>, but
+    you can easily define it yourself:
+
+<programlisting>
+attrValues = attrs: map (name: builtins.getAttr name attrs) (builtins.attrNames attrs);</programlisting>
+
+    </para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>baseNameOf</function> <replaceable>s</replaceable></term>
+
+    <listitem><para>Return the <emphasis>base name</emphasis> of the
+    string <replaceable>s</replaceable>, that is, everything following
+    the final slash in the string.  This is similar to the GNU
+    <command>basename</command> command.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><varname>builtins</varname></term>
+
+    <listitem><para>The attribute set <varname>builtins</varname>
+    contains all the built-in functions and values.  You can use
+    <varname>builtins</varname> to test for the availability of
+    features in the Nix installation, e.g.,
+
+<programlisting>
+if builtins ? getEnv then builtins.getEnv "PATH" else ""</programlisting>
+
+    This allows a Nix expression to fall back gracefully on older Nix
+    installations that don’t have the desired built-in function.
+    However, in that case you should not write
+
+<programlisting>
+if builtins ? getEnv then __getEnv "PATH" else ""</programlisting>
+
+    This Nix expression will trigger an “undefined variable” error on
+    older Nix versions since <function>__getEnv</function> doesn’t
+    exist.  <literal>builtins.getEnv</literal>, on the other hand, is
+    safe since <literal>builtins</literal> always exists and attribute
+    selection is lazy, so it’s only performed if the test
+    succeeds.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry
+  xml:id='builtin-currentSystem'><term><varname>builtins.currentSystem</varname></term>
+
+    <listitem><para>The built-in value <varname>currentSystem</varname>
+    evaluates to the Nix platform identifier for the Nix installation
+    on which the expression is being evaluated, such as
+    <literal>"i686-linux"</literal> or
+    <literal>"powerpc-darwin"</literal>.</para></listitem>
+
+  </varlistentry>
+
+
+  <!--
+  <varlistentry><term><function>currentTime</function></term>
+
+    <listitem><para>The built-in value <varname>currentTime</varname>
+    returns the current system time in seconds since 00:00:00 1/1/1970
+    UTC.  Due to the evaluation model of Nix expressions
+    (<emphasis>maximal laziness</emphasis>), it always yields the same
+    value within an execution of Nix.</para></listitem>
+
+  </varlistentry>
+  -->
+
+  
+  <!--
+  <varlistentry><term><function>dependencyClosure</function></term>
+
+    <listitem><para>TODO</para></listitem>
+
+  </varlistentry>
+  -->
+
+  
+  <varlistentry><term><function>derivation</function>
+  <replaceable>attrs</replaceable></term>
+
+    <listitem><para><function>derivation</function> is described in
+    <xref linkend='ssec-derivation' />.</para></listitem>
+
+  </varlistentry>
+
+
+  <varlistentry><term><function>dirOf</function> <replaceable>s</replaceable></term>
+
+    <listitem><para>Return the directory part of the string
+    <replaceable>s</replaceable>, that is, everything before the final
+    slash in the string.  This is similar to the GNU
+    <command>dirname</command> command.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.filterSource</function>
+  <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
+
+    <listitem>
+
+      <para>This function allows you to copy sources into the Nix
+      store while filtering certain files.  For instance, suppose that
+      you want to use the directory <filename>source-dir</filename> as
+      an input to a Nix expression, e.g.
+
+<programlisting>
+stdenv.mkDerivation {
+  ...
+  src = ./source-dir;
+}
+</programlisting>
+
+      However, if <filename>source-dir</filename> is a Subversion
+      working copy, then all those annoying <filename>.svn</filename>
+      subdirectories will also be copied to the store.  Worse, the
+      contents of those directories may change a lot, causing lots of
+      spurious rebuilds.  With <function>filterSource</function> you
+      can filter out the <filename>.svn</filename> directories:
+
+<programlisting>
+  src = builtins.filterSource
+    (path: type: type != "directory" || baseNameOf path != ".svn")
+    ./source-dir;
+</programlisting>
+
+      </para>
+
+      <para>Thus, the first argument <replaceable>e1</replaceable>
+      must be a predicate function that is called for each regular
+      file, directory or symlink in the source tree
+      <replaceable>e2</replaceable>.  If the function returns
+      <literal>true</literal>, the file is copied to the Nix store,
+      otherwise it is omitted.  The function is called with two
+      arguments.  The first is the full path of the file.  The second
+      is a string that identifies the type of the file, which is
+      either <literal>"regular"</literal>,
+      <literal>"directory"</literal>, <literal>"symlink"</literal> or
+      <literal>"unknown"</literal> (for other kinds of files such as
+      device nodes or fifos — but note that those cannot be copied to
+      the Nix store, so if the predicate returns
+      <literal>true</literal> for them, the copy will fail).</para>
+
+    </listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.getAttr</function>
+  <replaceable>s</replaceable> <replaceable>attrs</replaceable></term>
+
+    <listitem><para><function>getAttr</function> returns the attribute
+    named <replaceable>s</replaceable> from the attribute set
+    <replaceable>attrs</replaceable>.  Evaluation aborts if the
+    attribute doesn’t exist.  This is a dynamic version of the
+    <literal>.</literal> operator, since <replaceable>s</replaceable>
+    is an expression rather than an identifier.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.getEnv</function>
+  <replaceable>s</replaceable></term>
+
+    <listitem><para><function>getEnv</function> returns the value of
+    the environment variable <replaceable>s</replaceable>, or an empty
+    string if the variable doesn’t exist.  This function should be
+    used with care, as it can introduce all sorts of nasty environment
+    dependencies in your Nix expression.</para>
+
+    <para><function>getEnv</function> is used in Nix Packages to
+    locate the file <filename>~/.nixpkgs/config.nix</filename>, which
+    contains user-local settings for Nix Packages.  (That is, it does
+    a <literal>getEnv "HOME"</literal> to locate the user’s home
+    directory.)</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.hasAttr</function>
+  <replaceable>s</replaceable> <replaceable>attrs</replaceable></term>
+
+    <listitem><para><function>hasAttr</function> returns
+    <literal>true</literal> if the attribute set
+    <replaceable>attrs</replaceable> has an attribute named
+    <replaceable>s</replaceable>, and <literal>false</literal>
+    otherwise.  This is a dynamic version of the <literal>?</literal>
+    operator, since <replaceable>s</replaceable> is an expression
+    rather than an identifier.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.head</function>
+  <replaceable>list</replaceable></term>
+
+    <listitem><para>Return the first element of a list; abort
+    evaluation if the argument isn’t a list or is an empty list.  You
+    can test whether a list is empty by comparing it with
+    <literal>[]</literal>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>import</function>
+  <replaceable>path</replaceable></term>
+
+    <listitem><para>Load, parse and return the Nix expression in the
+    file <replaceable>path</replaceable>.  Evaluation aborts if the
+    file doesn’t exist or contains an incorrect Nix
+    expression.  <function>import</function> implements Nix’s module
+    system: you can put any Nix expression (such as an attribute set
+    or a function) in a separate file, and use it from Nix expressions
+    in other files.</para>
+
+    <para>A Nix expression loaded by <function>import</function> must
+    not contain any <emphasis>free variables</emphasis> (identifiers
+    that are not defined in the Nix expression itself and are not
+    built-in).  Therefore, it cannot refer to variables that are in
+    scope at the call site.  For instance, if you have a calling
+    expression
+    
+<programlisting>
+rec {
+  x = 123;
+  y = import ./foo.nix;
+}</programlisting>
+
+    then the following <filename>foo.nix</filename> will give an
+    error:
+
+<programlisting>
+x + 456</programlisting>
+
+    since <varname>x</varname> is not in scope in
+    <filename>foo.nix</filename>.  If you want <varname>x</varname>
+    to be available in <filename>foo.nix</filename>, you should pass
+    it as a function argument:
+
+<programlisting>
+rec {
+  x = 123;
+  y = import ./foo.nix x;
+}</programlisting>
+
+    and
+
+<programlisting>
+x: x + 456</programlisting>
+
+    (The function argument doesn’t have to be called
+    <varname>x</varname> in <filename>foo.nix</filename>; any name
+    would work.)</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.isAttrs</function>
+  <replaceable>e</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if
+    <replaceable>e</replaceable> evaluates to an attribute set, and
+    <literal>false</literal> otherwise.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.isList</function>
+  <replaceable>e</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if
+    <replaceable>e</replaceable> evaluates to a list, and
+    <literal>false</literal> otherwise.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.isFunction</function>
+  <replaceable>e</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if
+    <replaceable>e</replaceable> evaluates to a function, and
+    <literal>false</literal> otherwise.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>isNull</function>
+  <replaceable>e</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if
+    <replaceable>e</replaceable> evaluates to <literal>null</literal>,
+    and <literal>false</literal> otherwise.</para>
+
+    <warning><para>This function is <emphasis>deprecated</emphasis>;
+    just write <literal>e == null</literal> instead.</para></warning>
+    
+    </listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.lessThan</function>
+  <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if the integer
+    <replaceable>e1</replaceable> is less than the integer
+    <replaceable>e2</replaceable>, and <literal>false</literal>
+    otherwise.  Evaluation aborts if either
+    <replaceable>e1</replaceable> or <replaceable>e2</replaceable>
+    does not evaluate to an integer.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.listToAttrs</function>
+  <replaceable>e</replaceable></term>
+
+    <listitem><para>Construct an attribute set from a list specifying
+    the names and values of each attribute.  Each element of the list
+    should be an attribute set consisting of a string-valued attribute
+    <varname>name</varname> specifying the name of the attribute, and
+    an attribute <varname>value</varname> specifying its value.
+    Example:
+
+<programlisting>
+builtins.listToAttrs [
+  {name = "foo"; value = 123;}
+  {name = "bar"; value = 456;}
+]
+</programlisting>
+
+    evaluates to
+
+<programlisting>
+{ foo = 123; bar = 456; }
+</programlisting>
+
+    </para></listitem>
+
+  </varlistentry>
+  
+  <varlistentry><term><function>map</function>
+  <replaceable>f</replaceable> <replaceable>list</replaceable></term>
+
+    <listitem><para>Apply the function <replaceable>f</replaceable> to
+    each element in the list <replaceable>list</replaceable>.  For
+    example,
+
+<programlisting>
+map (x: "foo" + x) ["bar" "bla" "abc"]</programlisting>
+
+    evaluates to <literal>["foobar" "foobla"
+    "fooabc"]</literal>.</para></listitem>
+    
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.pathExists</function>
+  <replaceable>path</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if the path
+    <replaceable>path</replaceable> exists, and
+    <literal>false</literal> otherwise.  One application of this
+    function is to conditionally include a Nix expression containing
+    user configuration:
+
+<programlisting>
+let
+  fileName = builtins.getEnv "CONFIG_FILE";
+  config =
+    if fileName != "" &amp;&amp; builtins.pathExists (builtins.toPath fileName)
+    then import (builtins.toPath fileName)
+    else { someSetting = false; }; <lineannotation># default configuration</lineannotation>
+in config.someSetting</programlisting>
+
+    (Note that <envar>CONFIG_FILE</envar> must be an absolute path for
+    this to work.)</para></listitem>
+
+  </varlistentry>
+
+
+  <!--
+  <varlistentry><term><function>relativise</function></term>
+
+    <listitem><para>TODO</para></listitem>
+
+  </varlistentry>
+  -->
+
+  
+  <varlistentry><term><function>builtins.readFile</function>
+  <replaceable>path</replaceable></term>
+
+    <listitem><para>Return the contents of the file
+    <replaceable>path</replaceable> as a string.</para></listitem>
+
+  </varlistentry>
+  
+  
+  <varlistentry><term><function>removeAttrs</function>
+  <replaceable>attrs</replaceable> <replaceable>list</replaceable></term>
+
+    <listitem><para>Remove the attributes listed in
+    <replaceable>list</replaceable> from the attribute set
+    <replaceable>attrs</replaceable>.  The attributes don’t have to
+    exist in <replaceable>attrs</replaceable>. For instance,
+
+<screen>
+removeAttrs { x = 1; y = 2; z = 3; } ["a" "x" "z"]</screen>
+
+    evaluates to <literal>{y = 2;}</literal>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.stringLength</function>
+  <replaceable>e</replaceable></term>
+
+    <listitem><para>Return the length of the string
+    <replaceable>e</replaceable>.  If <replaceable>e</replaceable> is
+    not a string, evaluation is aborted.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.sub</function>
+  <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
+
+    <listitem><para>Return the difference between the integers
+    <replaceable>e1</replaceable> and
+    <replaceable>e2</replaceable>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.substring</function>
+  <replaceable>start</replaceable> <replaceable>len</replaceable>
+  <replaceable>s</replaceable></term>
+
+    <listitem><para>Return the substring of
+    <replaceable>s</replaceable> from character position
+    <replaceable>start</replaceable> (zero-based) up to but not
+    including <replaceable>start + len</replaceable>.  If
+    <replaceable>start</replaceable> is greater than the length of the
+    string, an empty string is returned, and if <replaceable>start +
+    len</replaceable> lies beyond the end of the string, only the
+    substring up to the end of the string is returned.
+    <replaceable>start</replaceable> must be
+    non-negative.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.tail</function>
+  <replaceable>list</replaceable></term>
+
+    <listitem><para>Return the second to last elements of a list;
+    abort evaluation if the argument isn’t a list or is an empty
+    list.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>throw</function>
+  <replaceable>s</replaceable></term>
+
+    <listitem><para>Throw an error message
+    <replaceable>s</replaceable>.  This usually aborts Nix expression
+    evaluation, but in <command>nix-env -qa</command> and other
+    commands that try to evaluate a set of derivations to get
+    information about those derivations, a derivation that throws an
+    error is silently skipped (which is not the case for
+    <function>abort</function>).</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry
+  xml:id='builtin-toFile'><term><function>builtins.toFile</function>
+  <replaceable>name</replaceable> <replaceable>s</replaceable></term>
+
+    <listitem><para>Store the string <replaceable>s</replaceable> in a
+    file in the Nix store and return its path.  The file has suffix
+    <replaceable>name</replaceable>.  This file can be used as an
+    input to derivations.  One application is to write builders
+    “inline”.  For instance, the following Nix expression combines
+    <xref linkend='ex-hello-nix' /> and <xref
+    linkend='ex-hello-builder' /> into one file:
+
+<programlisting>
+{stdenv, fetchurl, perl}:
+
+stdenv.mkDerivation {
+  name = "hello-2.1.1";
+  
+  builder = builtins.toFile "builder.sh" "
+    source $stdenv/setup
+
+    PATH=$perl/bin:$PATH
+
+    tar xvfz $src
+    cd hello-*
+    ./configure --prefix=$out
+    make
+    make install
+  ";
+
+  src = fetchurl {
+    url = http://nix.cs.uu.nl/dist/tarballs/hello-2.1.1.tar.gz;
+    md5 = "70c9ccf9fac07f762c24f2df2290784d";
+  };
+  inherit perl;
+}</programlisting>
+  
+    </para>
+
+    <para>It is even possible for one file to refer to another, e.g.,
+
+<programlisting>
+  builder = let
+    configFile = builtins.toFile "foo.conf" "
+      # This is some dummy configuration file.
+      <replaceable>...</replaceable>
+    ";
+  in builtins.toFile "builder.sh" "
+    source $stdenv/setup
+    <replaceable>...</replaceable>
+    cp ${configFile} $out/etc/foo.conf
+  ";</programlisting>
+
+    Note that <literal>${configFile}</literal> is an antiquotation
+    (see <xref linkend='ssec-values' />), so the result of the
+    expression <literal>configFile</literal> (i.e., a path like
+    <filename>/nix/store/m7p7jfny445k...-foo.conf</filename>) will be
+    spliced into the resulting string.</para>
+
+    <para>It is however <emphasis>not</emphasis> allowed to have files
+    mutually referring to each other, like so:
+
+<programlisting>
+let
+  foo = builtins.toFile "foo" "...${bar}...";
+  bar = builtins.toFile "bar" "...${foo}...";
+in foo</programlisting>
+
+    This is not allowed because it would cause a cyclic dependency in
+    the computation of the cryptographic hashes for
+    <varname>foo</varname> and <varname>bar</varname>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.toPath</function> <replaceable>s</replaceable></term>
+
+    <listitem><para>Convert the string value
+    <replaceable>s</replaceable> into a path value.  The string
+    <replaceable>s</replaceable> must represent an absolute path
+    (i.e., must start with <literal>/</literal>).  The path need not
+    exist.  The resulting path is canonicalised, e.g.,
+    <literal>builtins.toPath "//foo/xyzzy/../bar/"</literal> returns
+    <literal>/foo/bar</literal>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>toString</function> <replaceable>e</replaceable></term>
+
+    <listitem><para>Convert the expression
+    <replaceable>e</replaceable> to a string.
+    <replaceable>e</replaceable> can be a string (in which case
+    <function>toString</function> is a no-op) or a path (e.g.,
+    <literal>toString /foo/bar</literal> yields
+    <literal>"/foo/bar"</literal>.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry xml:id='builtin-toXML'><term><function>builtins.toXML</function> <replaceable>e</replaceable></term>
+
+    <listitem><para>Return a string containing an XML representation
+    of <replaceable>e</replaceable>.  The main application for
+    <function>toXML</function> is to communicate information with the
+    builder in a more structured format than plain environment
+    variables.</para>
+
+    <!-- TODO: more formally describe the schema of the XML
+    representation -->
+
+    <para><xref linkend='ex-toxml' /> shows an example where this is
+    the case.  The builder is supposed to generate the configuration
+    file for a <link xlink:href='http://jetty.mortbay.org/'>Jetty
+    servlet container</link>.  A servlet container contains a number
+    of servlets (<filename>*.war</filename> files) each exported under
+    a specific URI prefix.  So the servlet configuration is a list of
+    attribute sets containing the <varname>path</varname> and
+    <varname>war</varname> of the servlet (<xref
+    linkend='ex-toxml-co-servlets' />).  This kind of information is
+    difficult to communicate with the normal method of passing
+    information through an environment variable, which just
+    concatenates everything together into a string (which might just
+    work in this case, but wouldn’t work if fields are optional or
+    contain lists themselves).  Instead the Nix expression is
+    converted to an XML representation with
+    <function>toXML</function>, which is unambiguous and can easily be
+    processed with the appropriate tools.  For instance, in the
+    example an XSLT stylesheet (<xref linkend='ex-toxml-co-stylesheet'
+    />) is applied to it (<xref linkend='ex-toxml-co-apply' />) to
+    generate the XML configuration file for the Jetty server.  The XML
+    representation produced from <xref linkend='ex-toxml-co-servlets'
+    /> by <function>toXML</function> is shown in <xref
+    linkend='ex-toxml-result' />.</para>
+
+    <para>Note that <xref linkend='ex-toxml' /> uses the <function
+    linkend='builtin-toFile'>toFile</function> built-in to write the
+    builder and the stylesheet “inline” in the Nix expression.  The
+    path of the stylesheet is spliced into the builder at
+    <literal>xsltproc ${stylesheet}
+    <replaceable>...</replaceable></literal>.</para>
+
+    <example xml:id='ex-toxml'><title>Passing information to a builder
+    using <function>toXML</function></title>
+    
+<programlisting><![CDATA[
+{stdenv, fetchurl, libxslt, jira, uberwiki}:
+
+stdenv.mkDerivation (rec {
+  name = "web-server";
+
+  buildInputs = [libxslt];
+  
+  builder = builtins.toFile "builder.sh" "
+    source $stdenv/setup
+    mkdir $out
+    echo $servlets | xsltproc ${stylesheet} - > $out/server-conf.xml]]> <co xml:id='ex-toxml-co-apply' /> <![CDATA[
+  ";
+
+  stylesheet = builtins.toFile "stylesheet.xsl"]]> <co xml:id='ex-toxml-co-stylesheet' /> <![CDATA[
+   "<?xml version='1.0' encoding='UTF-8'?>
+    <xsl:stylesheet xmlns:xsl='http://www.w3.org/1999/XSL/Transform' version='1.0'>
+      <xsl:template match='/'>
+        <Configure>
+          <xsl:for-each select='/expr/list/attrs'>
+            <Call name='addWebApplication'>
+              <Arg><xsl:value-of select=\"attr[@name = 'path']/string/@value\" /></Arg>
+              <Arg><xsl:value-of select=\"attr[@name = 'war']/path/@value\" /></Arg>
+            </Call>
+          </xsl:for-each>
+        </Configure>
+      </xsl:template>
+    </xsl:stylesheet>
+  ";
+
+  servlets = builtins.toXML []]> <co xml:id='ex-toxml-co-servlets' /> <![CDATA[
+    { path = "/bugtracker"; war = jira + "/lib/atlassian-jira.war"; }
+    { path = "/wiki"; war = uberwiki + "/uberwiki.war"; }
+  ];
+})]]></programlisting>
+
+    </example>
+
+    <example xml:id='ex-toxml-result'><title>XML representation produced by
+    <function>toXML</function></title>
+    
+<programlisting><![CDATA[<?xml version='1.0' encoding='utf-8'?>
+<expr>
+  <list>
+    <attrs>
+      <attr name="path">
+        <string value="/bugtracker" />
+      </attr>
+      <attr name="war">
+        <path value="/nix/store/d1jh9pasa7k2...-jira/lib/atlassian-jira.war" />
+      </attr>
+    </attrs>
+    <attrs>
+      <attr name="path">
+        <string value="/wiki" />
+      </attr>
+      <attr name="war">
+        <path value="/nix/store/y6423b1yi4sx...-uberwiki/uberwiki.war" />
+      </attr>
+    </attrs>
+  </list>
+</expr>]]></programlisting>
+
+    </example>
+
+    </listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><function>builtins.trace</function>
+  <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
+
+    <listitem><para>Evaluate <replaceable>e1</replaceable> and print its
+    abstract syntax representation on standard error.  Then return
+    <replaceable>e2</replaceable>.  This function is useful for
+    debugging.</para></listitem>
+
+  </varlistentry>
+
+  
+</variablelist>
+
+
+</section>
--- a/doc/manual/conf-file.xml
+++ b/doc/manual/conf-file.xml
@@ -0,0 +1,264 @@
+<section xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id="sec-conf-file">
+
+<title>Nix configuration file</title>
+
+
+<para>A number of persistent settings of Nix are stored in the file
+<filename><replaceable>prefix</replaceable>/etc/nix/nix.conf</filename>.
+This file is a list of <literal><replaceable>name</replaceable> =
+<replaceable>value</replaceable></literal> pairs, one per line.
+Comments start with a <literal>#</literal> character.  An example
+configuration file is shown in <xref linkend="ex-nix-conf" />.</para>
+
+<example xml:id='ex-nix-conf'><title>Nix configuration file</title>
+
+<programlisting>
+gc-keep-outputs = true       # Nice for developers
+gc-keep-derivations = true   # Idem
+env-keep-derivations = false
+</programlisting>
+</example>
+
+<para>The following variables are currently available: 
+
+<variablelist>
+
+  
+  <varlistentry xml:id="conf-gc-keep-outputs"><term><literal>gc-keep-outputs</literal></term>
+
+    <listitem><para>If <literal>true</literal>, the garbage collector
+    will keep the outputs of non-garbage derivations.  If
+    <literal>false</literal> (default), outputs will be deleted unless
+    they are GC roots themselves (or reachable from other roots).</para>
+ 
+    <para>In general, outputs must be registered as roots separately.
+    However, even if the output of a derivation is registered as a
+    root, the collector will still delete store paths that are used
+    only at build time (e.g., the C compiler, or source tarballs
+    downloaded from the network).  To prevent it from doing so, set
+    this option to <literal>true</literal>.</para></listitem>
+
+  </varlistentry>
+  
+
+  <varlistentry xml:id="conf-gc-keep-derivations"><term><literal>gc-keep-derivations</literal></term>
+
+    <listitem><para>If <literal>true</literal> (default), the garbage
+    collector will keep the derivations from which non-garbage store
+    paths were built.  If <literal>false</literal>, they will be
+    deleted unless explicitly registered as a root (or reachable from
+    other roots).</para>
+
+    <para>Keeping derivation around is useful for querying and
+    traceability (e.g., it allows you to ask with what dependencies or
+    options a store path was built), so by default this option is on.
+    Turn it off to safe a bit of disk space (or a lot if
+    <literal>gc-keep-outputs</literal> is also turned on).</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry xml:id="conf-gc-reserved-space"><term><literal>gc-reserved-space</literal></term>
+
+    <listitem><para>This option specifies how much space should be
+    reserved in normal use so that the garbage collector can run
+    succesfully.  Since the garbage collector must perform Berkeley DB
+    transactions, it needs some disk space for itself.  However, when
+    the disk is full, this space is not available, so the collector
+    would not be able to run precisely when it is most needed.</para>
+
+    <para>For this reason, when Nix is run, it allocates a file
+    <filename>/nix/var/nix/db/reserved</filename> of the size
+    specified by this option.  When the garbage collector is run, this
+    file is deleted before the Berkeley DB environment is opened.
+    This should give it enough room to proceed.</para>
+
+    <para>The default is <literal>1048576</literal> (1
+    MiB).</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><literal>env-keep-derivations</literal></term>
+
+    <listitem><para>If <literal>false</literal> (default), derivations
+    are not stored in Nix user environments.  That is, the derivation
+    any build-time-only dependencies may be garbage-collected.</para>
+
+    <para>If <literal>true</literal>, when you add a Nix derivation to
+    a user environment, the path of the derivation is stored in the
+    user environment.  Thus, the derivation will not be
+    garbage-collected until the user environment generation is deleted
+    (<command>nix-env --delete-generations</command>).  To prevent
+    build-time-only dependencies from being collected, you should also
+    turn on <literal>gc-keep-outputs</literal>.</para>
+
+    <para>The difference between this option and
+    <literal>gc-keep-derivations</literal> is that this one is
+    “sticky”: it applies to any user environment created while this
+    option was enabled, while <literal>gc-keep-derivations</literal>
+    only applies at the moment the garbage collector is
+    run.</para></listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry xml:id="conf-build-max-jobs"><term><literal>build-max-jobs</literal></term>
+
+    <listitem><para>This option defines the maximum number of jobs
+    that Nix will try to build in parallel.  The default is
+    <literal>1</literal>.  You should generally set it to the number
+    of CPUs in your system (e.g., <literal>2</literal> on a Athlon 64
+    X2).  It can be overriden using the <option
+    linkend='opt-max-jobs'>--max-jobs</option> (<option>-j</option>)
+    command line switch.</para></listitem>
+
+  </varlistentry>
+
+
+  <varlistentry xml:id="conf-build-max-silent-time"><term><literal>build-max-silent-time</literal></term>
+
+    <listitem>
+
+      <para>This option defines the maximum number of seconds that a
+      builder can go without producing any data on standard output or
+      standard error.  This is useful (for instance in a automated
+      build system) to catch builds that are stuck in an infinite
+      loop, or to catch remote builds that are hanging due to network
+      problems.  It can be overriden using the <option
+      linkend="opt-max-silent-time">--max-silent-time</option> command
+      line switch.</para>
+
+      <para>The value <literal>0</literal> means that there is no
+      timeout.  This is also the default.</para>
+
+    </listitem>
+
+  </varlistentry>
+
+
+  <varlistentry xml:id="conf-build-users-group"><term><literal>build-users-group</literal></term>
+
+    <listitem><para>This options specifies the Unix group containing
+    the Nix build user accounts.  In multi-user Nix installations,
+    builds should not be performed by the Nix account since that would
+    allow users to arbitrarily modify the Nix store and database by
+    supplying specially crafted builders; and they cannot be performed
+    by the calling user since that would allow him/her to influence
+    the build result.</para>
+
+    <para>Therefore, if this option is non-empty and specifies a valid
+    group, builds will be performed under the user accounts that are a
+    member of the group specified here (as listed in
+    <filename>/etc/group</filename>).  Those user accounts should not
+    be used for any other purpose!</para>
+
+    <para>Nix will never run two builds under the same user account at
+    the same time.  This is to prevent an obvious security hole: a
+    malicious user writing a Nix expression that modifies the build
+    result of a legitimate Nix expression being built by another user.
+    Therefore it is good to have as many Nix build user accounts as
+    you can spare.  (Remember: uids are cheap.)</para>
+
+    <para>The build users should have permission to create files in
+    the Nix store, but not delete them.  Therefore,
+    <filename>/nix/store</filename> should be owned by the Nix
+    account, its group should be the group specified here, and its
+    mode should be <literal>1775</literal>.</para>
+
+    <para>If the build users group is empty, builds will be performed
+    under the uid of the Nix process (that is, the uid of the caller
+    if <envar>NIX_REMOTE</envar> is empty, the uid under which the Nix
+    daemon runs if <envar>NIX_REMOTE</envar> is
+    <literal>daemon</literal>, or the uid that owns the setuid
+    <command>nix-worker</command> program if <envar>NIX_REMOTE</envar>
+    is <literal>slave</literal>).  Obviously, this should not be used
+    in multi-user settings with untrusted users.</para>
+
+    </listitem>
+
+  </varlistentry>
+
+
+  <varlistentry><term><literal>build-use-chroot</literal></term>
+
+    <listitem><para>If set to <literal>true</literal>, builds will be
+    performed in a <emphasis>chroot environment</emphasis>, i.e., the
+    build will be isolated from the normal file system hierarchy and
+    will only see the Nix store, the temporary build directory, and
+    the directories configured with the <link
+    linkend='conf-build-chroot-dirs'><literal>build-chroot-dirs</literal>
+    option</link> (such as <filename>/proc</filename> and
+    <filename>/dev</filename>).  This is useful to prevent undeclared
+    dependencies on files in directories such as
+    <filename>/usr/bin</filename>.</para>
+
+    <para>The use of a chroot requires that Nix is run as root (but
+    you can still use the <link
+    linkend='conf-build-users-group'>“build users” feature</link> to
+    perform builds under different users than root).  Currently,
+    chroot builds only work on Linux because Nix uses “bind mounts” to
+    make the Nix store and other directories available inside the
+    chroot.</para>
+
+    </listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry xml:id="conf-build-chroot-dirs"><term><literal>build-chroot-dirs</literal></term>
+
+    <listitem><para>When builds are performed in a chroot environment,
+    Nix will mount (using <command>mount --bind</command> on Linux)
+    some directories from the normal file system hierarchy inside the
+    chroot.  These are the Nix store, the temporary build directory
+    (usually
+    <filename>/tmp/nix-<replaceable>pid</replaceable>-<replaceable>number</replaceable></filename>)
+    and the directories listed here.  The default is <literal>dev
+    /proc</literal>.  Files in <filename>/dev</filename> (such as
+    <filename>/dev/null</filename>) are needed by many builds, and
+    some files in <filename>/proc</filename> may also be needed
+    occasionally.</para>
+
+    <para>The value used on NixOS is
+    
+<programlisting>
+build-use-chroot = /dev /proc /bin</programlisting>
+
+    to make the <filename>/bin/sh</filename> symlink available (which
+    is still needed by many builders).</para>
+
+    </listitem>
+
+  </varlistentry>
+
+  
+  <varlistentry><term><literal>system</literal></term>
+
+    <listitem><para>This option specifies the canonical Nix system
+    name of the current installation, such as
+    <literal>i686-linux</literal> or
+    <literal>powerpc-darwin</literal>.  Nix can only build derivations
+    whose <literal>system</literal> attribute equals the value
+    specified here.  In general, it never makes sense to modify this
+    value from its default, since you can use it to ‘lie’ about the
+    platform you are building on (e.g., perform a Mac OS build on a
+    Linux machine; the result would obviously be wrong).  It only
+    makes sense if the Nix binaries can run on multiple platforms,
+    e.g., ‘universal binaries’ that run on <literal>powerpc-darwin</literal> and
+    <literal>i686-darwin</literal>.</para>
+
+    <para>It defaults to the canonical Nix system name detected by
+    <filename>configure</filename> at build time.</para></listitem>
+
+  </varlistentry>
+  
+    
+</variablelist>
+
+</para>
+
+
+</section>
--- a/doc/manual/env-common.xml
+++ b/doc/manual/env-common.xml
@@ -0,0 +1,280 @@
+<section xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id="sec-common-env">
+
+<title>Common environment variables</title>
+
+
+<para>Most Nix commands interpret the following environment variables:</para>
+
+<variablelist>
+
+  
+<varlistentry><term><envar>NIX_IGNORE_SYMLINK_STORE</envar></term>
+
+  <listitem>
+
+  <para>Normally, the Nix store directory (typically
+  <filename>/nix/store</filename>) is not allowed to contain any
+  symlink components.  This is to prevent “impure” builds.  Builders
+  sometimes “canonicalise” paths by resolving all symlink components.
+  Thus, builds on different machines (with
+  <filename>/nix/store</filename> resolving to different locations)
+  could yield different results.  This is generally not a problem,
+  except when builds are deployed to machines where
+  <filename>/nix/store</filename> resolves differently.  If you are
+  sure that you’re not going to do that, you can set
+  <envar>NIX_IGNORE_SYMLINK_STORE</envar> to <envar>1</envar>.</para>
+
+  <para>Note that if you’re symlinking the Nix store so that you can
+  put it on another file system than the root file system, on Linux
+  you’re better off using <literal>bind</literal> mount points, e.g.,
+
+  <screen>
+$ mkdir /nix   
+$ mount -o bind /mnt/otherdisk/nix /nix</screen>
+
+  Consult the <citerefentry><refentrytitle>mount</refentrytitle>
+  <manvolnum>8</manvolnum></citerefentry> manual page for details.</para>
+
+  </listitem>
+
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_STORE_DIR</envar></term>
+
+  <listitem><para>Overrides the location of the Nix store (default
+  <filename><replaceable>prefix</replaceable>/store</filename>).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_DATA_DIR</envar></term>
+
+  <listitem><para>Overrides the location of the Nix static data
+  directory (default
+  <filename><replaceable>prefix</replaceable>/share</filename>).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_LOG_DIR</envar></term>
+
+  <listitem><para>Overrides the location of the Nix log directory
+  (default <filename><replaceable>prefix</replaceable>/log/nix</filename>).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_STATE_DIR</envar></term>
+
+  <listitem><para>Overrides the location of the Nix state directory
+  (default <filename><replaceable>prefix</replaceable>/var/nix</filename>).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_DB_DIR</envar></term>
+
+  <listitem><para>Overrides the location of the Nix database (default
+  <filename><replaceable>$NIX_STATE_DIR</replaceable>/db</filename>, i.e.,
+  <filename><replaceable>prefix</replaceable>/var/nix/db</filename>).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_CONF_DIR</envar></term>
+
+  <listitem><para>Overrides the location of the Nix configuration
+  directory (default
+  <filename><replaceable>prefix</replaceable>/etc/nix</filename>).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><envar>NIX_LOG_TYPE</envar></term>
+
+  <listitem><para>Equivalent to the <link
+  linkend="opt-log-type"><option>--log-type</option>
+  option</link>.</para></listitem>
+
+</varlistentry>
+  
+
+<varlistentry><term><envar>TMPDIR</envar></term>
+
+  <listitem><para>Use the specified directory to store temporary
+  files.  In particular, this includes temporary build directories;
+  these can take up substantial amounts of disk space.  The default is
+  <filename>/tmp</filename>.</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry xml:id="envar-build-hook"><term><envar>NIX_BUILD_HOOK</envar></term>
+
+  <listitem>
+
+  <para>Specifies the location of the <emphasis>build hook</emphasis>,
+  which is a program (typically some script) that Nix will call
+  whenever it wants to build a derivation.  This is used to implement
+  distributed builds (see <xref linkend="sec-distributed-builds"
+  />).  The protocol by which the calling Nix process and the build
+  hook communicate is as follows.</para>
+
+  <para>The build hook is called with the following command-line
+  arguments:
+
+  <orderedlist>
+
+    <listitem><para>A boolean value <literal>0</literal> or
+    <literal>1</literal> specifying whether Nix can locally execute
+    more builds, as per the <link
+    linkend="opt-max-jobs"><option>--max-jobs</option> option</link>.
+    The purpose of this argument is to allow the hook to not have to
+    maintain bookkeeping for the local machine.</para></listitem>
+
+    <listitem><para>The Nix platform identifier for the local machine
+    (e.g., <literal>i686-linux</literal>).</para></listitem>
+
+    <listitem><para>The Nix platform identifier for the derivation,
+    i.e., its <link linkend="attr-system"><varname>system</varname>
+    attribute</link>.</para></listitem>
+
+    <listitem><para>The store path of the derivation.</para></listitem>
+
+  </orderedlist>
+
+  </para>
+
+  <para>On the basis of this information, and whatever persistent
+  state the build hook keeps about other machines and their current
+  load, it has to decide what to do with the build.  It should print
+  out on file descriptor 3 one of the following responses (terminated
+  by a newline, <literal>"\n"</literal>):
+
+  <variablelist>
+
+    <varlistentry><term><literal>decline</literal></term>
+
+      <listitem><para>The build hook is not willing or able to perform
+      the build; the calling Nix process should do the build itself,
+      if possible.</para></listitem>
+
+    </varlistentry>
+
+    <varlistentry><term><literal>postpone</literal></term>
+
+      <listitem><para>The build hook cannot perform the build now, but
+      can do so in the future (e.g., because all available build slots
+      on remote machines are in use).  The calling Nix process should
+      postpone this build until at least one currently running build
+      has terminated.</para></listitem>
+
+    </varlistentry>
+
+    <varlistentry><term><literal>accept</literal></term>
+
+      <listitem><para>The build hook has accepted the
+      build.</para></listitem>
+
+    </varlistentry>
+
+  </variablelist>
+
+  </para>
+
+  <para>If the build hook accepts the build, it is possible that it is
+  no longer necessary to do the build because some other process has
+  performed the build in the meantime.  To prevent races, the hook
+  must read from file descriptor 4 a single line that tells it whether
+  to continue:
+
+  <variablelist>
+
+    <varlistentry><term><literal>cancel</literal></term>
+
+      <listitem><para>The build has already been done, so the hook
+      should exit.</para></listitem>
+
+    </varlistentry>
+  
+    <varlistentry><term><literal>okay</literal></term>
+
+      <listitem><para>The hook should proceed with the build.  At this
+      point, the calling Nix process has acquired locks on the output
+      path, so no other Nix process will perform the
+      build.</para></listitem>
+
+    </varlistentry>
+
+  </variablelist>
+
+  </para>
+
+  <para>If the hook has been told to proceed, Nix will store in the
+  hook’s current directory a number of text files that contain
+  information about the derivation:
+
+  <variablelist>
+
+    <varlistentry><term><filename>inputs</filename></term>
+
+      <listitem><para>The set of store paths that are inputs to the
+      build process (one per line).  These have to be copied
+      <emphasis>to</emphasis> the remote machine (in addition to the
+      store derivation itself).</para></listitem>
+
+    </varlistentry>
+  
+    <varlistentry><term><filename>outputs</filename></term>
+
+      <listitem><para>The set of store paths that are outputs of the
+      derivation (one per line).  These have to be copied
+      <emphasis>from</emphasis> the remote machine if the build
+      succeeds.</para></listitem>
+
+    </varlistentry>
+
+    <varlistentry><term><filename>references</filename></term>
+
+      <listitem><para>The reference graph of the inputs, in the format
+      accepted by the command <command>nix-store
+      --register-validity</command>.  It is necessary to run this
+      command on the remote machine after copying the inputs to inform
+      Nix on the remote machine that the inputs are valid
+      paths.</para></listitem>
+
+    </varlistentry>
+
+  </variablelist>
+
+  </para>
+
+  <para>The hook should copy the inputs to the remote machine,
+  register the validity of the inputs, perform the remote build, and
+  copy the outputs back to the local machine.  An exit code other than
+  <literal>0</literal> indicates that the hook has failed.</para>
+
+  </listitem>
+
+
+</varlistentry>
+
+
+<varlistentry xml:id="envar-remote"><term><envar>NIX_REMOTE</envar></term>
+
+  <listitem><para>This variable should be set to
+  <literal>daemon</literal> if you want to use the Nix daemon to
+  executed Nix operations, which is necessary in <link
+  linkend="ssec-multi-user">multi-user Nix installations</link>.
+  Otherwise, it should be left unset.</para></listitem>
+
+</varlistentry>
+
+    
+</variablelist>
+
+
+</section>
--- a/doc/manual/figures/user-environments.png
+++ b/doc/manual/figures/user-environments.png
--- a/doc/manual/figures/user-environments.sxd
+++ b/doc/manual/figures/user-environments.sxd
--- a/doc/manual/glossary.xml
+++ b/doc/manual/glossary.xml
@@ -0,0 +1,167 @@
+<appendix xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink">
+
+<title>Glossary</title>
+
+
+<glosslist>
+
+
+<glossentry xml:id="gloss-derivation"><glossterm>derivation</glossterm>
+
+  <glossdef><para>A description of a build action.  The result of a
+  derivation is a store object.  Derivations are typically specified
+  in Nix expressions using the <link
+  linkend="ssec-derivation"><function>derivation</function>
+  primitive</link>.  These are translated into low-level
+  <emphasis>store derivations</emphasis> (implicitly by
+  <command>nix-env</command> and <command>nix-build</command>, or
+  explicitly by <command>nix-instantiate</command>).</para></glossdef>
+
+</glossentry>
+
+
+<glossentry><glossterm>store</glossterm>
+
+  <glossdef><para>The location in the file system where store objects
+  live.  Typically <filename>/nix/store</filename>.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry><glossterm>store path</glossterm>
+
+  <glossdef><para>The location in the file system of a store object,
+  i.e., an immediate child of the Nix store
+  directory.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry><glossterm>store object</glossterm>
+
+  <glossdef><para>A file that is an immediate child of the Nix store
+  directory.  These can be regular files, but also entire directory
+  trees.  Store objects can be sources (objects copied from outside of
+  the store), derivation outputs (objects produced by running a build
+  action), or derivations (files describing a build
+  action).</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-substitute"><glossterm>substitute</glossterm>
+
+  <glossdef><para>A substitute is a command invocation stored in the
+  Nix database that describes how to build a store object, bypassing
+  normal the build mechanism (i.e., derivations).  Typically, the
+  substitute builds the store object by downloading a pre-built
+  version of the store object from some server.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry><glossterm>purity</glossterm>
+
+  <glossdef><para>The assumption that equal Nix derivations when run
+  always produce the same output.  This cannot be guaranteed in
+  general (e.g., a builder can rely on external inputs such as the
+  network or the system time) but the Nix model assumes
+  it.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry><glossterm>Nix expression</glossterm>
+
+  <glossdef><para>A high-level description of software packages and
+  compositions thereof.  Deploying software using Nix entails writing
+  Nix expressions for your packages.  Nix expressions are translated
+  to derivations that are stored in the Nix store.  These derivations
+  can then be built.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-reference"><glossterm>reference</glossterm>
+
+  <glossdef><para>A store path <varname>P</varname> is said to have a
+  reference to a store path <varname>Q</varname> if the store object
+  at <varname>P</varname> contains the path <varname>Q</varname>
+  somewhere.  This implies than an execution involving
+  <varname>P</varname> potentially needs <varname>Q</varname> to be
+  present.  The <emphasis>references</emphasis> of a store path are
+  the set of store paths to which it has a reference.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-closure"><glossterm>closure</glossterm>
+
+  <glossdef><para>The closure of a store path is the set of store
+  paths that are directly or indirectly “reachable” from that store
+  path; that is, it’s the closure of the path under the <link
+  linkend="gloss-reference">references</link> relation.  For instance,
+  if the store object at path <varname>P</varname> contains a
+  reference to path <varname>Q</varname>, then <varname>Q</varname> is
+  in the closure of <varname>P</varname>.  For correct deployment it
+  is necessary to deploy whole closures, since otherwise at runtime
+  files could be missing.  The command <command>nix-store
+  -qR</command> prints out closures of store paths.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-output-path"><glossterm>output path</glossterm>
+
+  <glossdef><para>A store path produced by a derivation.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-deriver"><glossterm>deriver</glossterm>
+
+  <glossdef><para>The deriver of an <link
+  linkend="gloss-output-path">output path</link> is the store
+  derivation that built it.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-validity"><glossterm>validity</glossterm>
+
+  <glossdef><para>A store path is considered
+  <emphasis>valid</emphasis> if it exists in the file system, is
+  listed in the Nix database as being valid, and if all paths in its
+  closure are also valid.</para></glossdef>
+
+</glossentry>
+
+
+<glossentry xml:id="gloss-user-env"><glossterm>user environment</glossterm>
+
+  <glossdef><para>An automatically generated store object that
+  consists of a set of symlinks to “active” applications, i.e., other
+  store paths.  These are generated automatically by <link
+  linkend="sec-nix-env"><command>nix-env</command></link>.  See <xref
+  linkend="sec-profiles" />.</para>
+
+  </glossdef>
+  
+</glossentry>
+
+
+<glossentry xml:id="gloss-profile"><glossterm>profile</glossterm>
+
+  <glossdef><para>A symlink to the current <link
+  linkend="gloss-user-env">user environment</link> of a user, e.g.,
+  <filename>/nix/var/nix/profiles/default</filename>.</para></glossdef>
+
+</glossentry>
+
+
+
+</glosslist>
+
+
+</appendix>
--- a/doc/manual/installation.xml
+++ b/doc/manual/installation.xml
@@ -1,211 +1,472 @@
-<chapter id='chap-installation'>
-  <title>Installation</title>
+<?xml version="1.0" encoding="utf-8"?>
+<chapter xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id="chap-installation">

-  <sect1>
-    <title>Obtaining Nix</title>
+<title>Installation</title>

-    <para>
-      The easiest way to obtain Nix is to download a <ulink
-      url='http://www.cs.uu.nl/groups/ST/Trace/Nix'>source
-      distribution</ulink>.  RPMs for SuSE and Red Hat are also
-      available.  These distributions are generated automatically.
-    </para>

-    <para>
-      Alternatively, the most recent sources of Nix can be obtained from its
-      <ulink url='https://svn.cs.uu.nl:12443/repos/trace/nix/trunk'>Subversion 
-        repository</ulink>.  For example, the following command will check out
-      the latest revision into a directory called <filename>nix</filename>:
-    </para>
+<section><title>Supported platforms</title>

-    <screen>
+<para>Nix is currently supported on the following platforms:
+
+<itemizedlist>
+
+  <listitem><para>Linux (particularly on x86, x86_64, and
+  PowerPC).</para></listitem>
+
+  <listitem><para>Mac OS X, both on Intel and
+  PowerPC.</para></listitem>
+
+  <listitem><para>FreeBSD (only tested on Intel).</para></listitem>
+
+  <listitem><para>Windows through <link
+  xlink:href="http://www.cygwin.com/">Cygwin</link>.</para>
+
+  <warning><para>On Cygwin, Nix <emphasis>must</emphasis> be installed
+  on an NTFS partition.  It will not work correctly on a FAT
+  partition.</para></warning>
+
+  </listitem>
+
+</itemizedlist>
+
+</para>
+
+<para>Nix is pretty portable, so it should work on most other Unix
+platforms as well.</para>
+
+</section>
+
+
+<section><title>Obtaining Nix</title>
+
+<para>The easiest way to obtain Nix is to download a <link
+xlink:href="http://nix.cs.uu.nl/">source distribution</link>.  RPMs
+for Red Hat, SuSE, and Fedora Core are also available.</para>
+
+<para>Alternatively, the most recent sources of Nix can be obtained
+from its <link
+xlink:href="https://svn.cs.uu.nl:12443/repos/trace/nix/trunk">Subversion
+repository</link>.  For example, the following command will check out
+the latest revision into a directory called
+<filename>nix</filename>:</para>
+
+<screen>
 $ svn checkout https://svn.cs.uu.nl:12443/repos/trace/nix/trunk nix</screen>

-    <para>
-      Likewise, specific releases can be obtained from the <ulink
-        url='https://svn.cs.uu.nl:12443/repos/trace/nix/tags'>tags
-        directory</ulink> of the repository.  If you don't have Subversion, you
-      can also download an automatically generated <ulink
-        url='https://svn.cs.uu.nl:12443/dist/trace/'>compressed
-        tar-file</ulink> of the head revision of the trunk.
-    </para>
+<para>Likewise, specific releases can be obtained from the <link
+xlink:href="https://svn.cs.uu.nl:12443/repos/trace/nix/tags">tags
+directory</link> of the repository.  If you don't have Subversion, you
+can also download an automatically generated <link
+xlink:href="https://svn.cs.uu.nl:12443/dist/trace/">compressed
+tar-file</link> of the head revision of the trunk.</para>

-  </sect1>
+</section>

-  <sect1>
-    <title>Prerequisites</title>

-    <para>
-      The following prerequisites only apply when you build from
-      source.  Binary releases (e.g., RPMs) have no prerequisites.
-    </para>
+<section><title>Prerequisites</title>

-    <para>
-      A fairly recent version of GCC/G++ is required.  Version 2.95
-      and higher should work.
-    </para>
+<para><emphasis>The following prerequisites only apply when you build
+from source</emphasis>.  Binary releases (e.g., RPMs) have no
+prerequisites.</para>

-    <para>
-      To build this manual and the man-pages you need the
-      <command>xmllint</command> and <command>xsltproc</command>
-      programs, which are part of the <literal>libxml2</literal> and
-      <literal>libxslt</literal> packages, respectively.  You also
-      need the <ulink
-      url='http://docbook.sourceforge.net/projects/xsl/'>DocBook XSL
-      stylesheets</ulink> and optionally the <ulink
-      url='http://www.oasis-open.org/docbook/xml/4.2/docbook-xml-4.2.zip'>
-      DocBook XML 4.2 DTD</ulink>.  Note that these are only required
-      if you modify the manual sources or when you are building from
-      the Subversion repository.
-    </para>
+<para>A fairly recent version of GCC/G++ is required.  Version 2.95
+and higher should work.</para>

-    <para>
-      To build the parser, very <emphasis>recent</emphasis> versions
-      of Bison and Flex are required.  (This is because Nix needs GLR
-      support in Bison and reentrancy support in Flex.)  For Bison,
-      you need version 1.875c or higher (1.875 does
-      <emphasis>not</emphasis> work), which can be obtained from the
-      <ulink url='ftp://alpha.gnu.org/pub/gnu/bison'>GNU FTP
-      server</ulink>.  For Flex, you need version 2.5.31, which is
-      available on <ulink
-      url='http://lex.sourceforge.net/'>SourceForge</ulink>.  Slightly
-      older versions may also work, but ancient versions like the
-      ubiquitous 2.5.4a won't.  Note that these are only required if
-      you modify the parser or when you are building from the
-      Subversion repository.
-    </para>
+<para>To build this manual and the man-pages you need the
+<command>xmllint</command> and <command>xsltproc</command> programs,
+which are part of the <literal>libxml2</literal> and
+<literal>libxslt</literal> packages, respectively.  You also need the
+<link
+xlink:href="http://docbook.sourceforge.net/projects/xsl/">DocBook XSL
+stylesheets</link> and optionally the <link
+xlink:href="http://www.docbook.org/schemas/5x"> DocBook 5.0 RELAX NG
+schemas</link>.  Note that these are only required if you modify the
+manual sources or when you are building from the Subversion
+repository.</para>

-    <para>
-      Nix uses Sleepycat's Berkeley DB and CWI's ATerm library.  These
-      are included in the Nix source distribution.  If you build from
-      the Subversion repository, you must download them yourself and
-      place them in the <filename>externals/</filename> directory.
-      See <filename>externals/Makefile.am</filename> for the precise
-      URLs of these packages.
-    </para>
-  </sect1>
+<para>To build the parser, very <emphasis>recent</emphasis> versions
+of Bison and Flex are required.  (This is because Nix needs GLR
+support in Bison and reentrancy support in Flex.)  For Bison, you need
+version 2.3 or higher (1.875 does <emphasis>not</emphasis> work),
+which can be obtained from
+the <link xlink:href="ftp://alpha.gnu.org/pub/gnu/bison">GNU FTP
+server</link>.  For Flex, you need version 2.5.33, which is available
+on <link xlink:href="http://lex.sourceforge.net/">SourceForge</link>.
+Slightly older versions may also work, but ancient versions like the
+ubiquitous 2.5.4a won't.  Note that these are only required if you
+modify the parser or when you are building from the Subversion
+repository.</para>

-  <sect1>
-    <title>Building Nix from source</title>
+<para>Nix uses Sleepycat's Berkeley DB, CWI's ATerm library and the
+bzip2 compressor (including the bzip2 library).  These are included in
+the Nix source distribution.  If you build from the Subversion
+repository, you must download them yourself and place them in the
+<filename>externals/</filename> directory.  See
+<filename>externals/Makefile.am</filename> for the precise URLs of
+these packages.  Alternatively, if you already have them installed,
+you can use <command>configure</command>'s
+<option>--with-bdb</option>, <option>--with-aterm</option> and
+<option>--with-bzip2</option> options to point to their respective
+locations.  Note that Berkeley DB <emphasis>must</emphasis> be version
+4.5; other versions may not have compatible database formats.</para>

-    <para>
-      After unpacking or checking out the Nix sources, issue the following
-      commands:
-    </para>
+</section>

-    <screen>
+
+<section><title>Building Nix from source</title>
+
+<para>After unpacking or checking out the Nix sources, issue the
+following commands:
+
+<screen>
 $ ./configure <replaceable>options...</replaceable>
 $ make
 $ make install</screen>

-    <para>
-      When building from the Subversion repository, these should be preceded by
-      the command:
-    </para>
+</para>

-    <screen>
-$ autoreconf -i</screen>
+<para>When building from the Subversion repository, these should be
+preceded by the command:

-    <para>
-      The installation path can be specified by passing the
-      <option>--prefix=<replaceable>prefix</replaceable></option> to
-      <command>configure</command>.  The default installation directory is
-      <filename>/nix</filename>.  You can change this to any location you like.
-      You must have write permission to the <replaceable>prefix</replaceable>
-      path.
-    </para>
+<screen>
+$ ./bootstrap</screen>

-    <warning>
-      <para>
-        It is advisable <emphasis>not</emphasis> to change the installation
-        prefix from its default, since doing so will in all likelihood make it
-        impossible to use derivations built on other systems.
-      </para>
-    </warning>
+</para>

-    <para>
-      If you want to rebuilt the documentation, pass the full path to the
-      DocBook XML catalog file (<filename>docbook.cat</filename>) and to the
-      DocBook XSL stylesheets using the
-      <option>--with-docbook-catalog=<replaceable>path</replaceable></option>
-      and <option>--with-docbook-xsl=<replaceable>path</replaceable></option>
-      options.
-    </para>
+<para>The installation path can be specified by passing the
+<option>--prefix=<replaceable>prefix</replaceable></option> to
+<command>configure</command>.  The default installation directory is
+<filename>/nix</filename>.  You can change this to any location you
+like.  You must have write permission to the
+<replaceable>prefix</replaceable> path.</para>

-  </sect1>
+<warning><para>It is best <emphasis>not</emphasis> to change the
+installation prefix from its default, since doing so makes it
+impossible to use pre-built binaries from the standard Nixpkgs
+channels.</para></warning>
+
+<para>If you want to rebuilt the documentation, pass the full path to
+the DocBook RELAX NG schemas and to the DocBook XSL stylesheets using
+the
+<option>--with-docbook-rng=<replaceable>path</replaceable></option>
+and
+<option>--with-docbook-xsl=<replaceable>path</replaceable></option>
+options.</para>
+
+</section>


-  <sect1>
-    <title>Installing from RPMs</title>
+<section><title>Installing from RPMs</title>

-    <para>
-      RPM packages of Nix can be downloaded from <ulink
-      url='http://www.cs.uu.nl/groups/ST/Trace/Nix' />.  These RPMs
-      should work for most fairly recent releases of SuSE and Red Hat
-      Linux.  They have been known to work work on SuSE Linux 8.1 and
-      9.0, and Red Hat 9.0.  In fact, it should work on any RPM-based
-      Linux distribution based on <literal>glibc</literal> 2.3 or
-      later.
-    </para>
+<para>RPM packages of Nix can be downloaded from <link
+xlink:href="http://nix.cs.uu.nl/" />.  These RPMs should work for most
+fairly recent releases of SuSE and Red Hat Linux.  They have been
+known to work work on SuSE Linux 8.1 and 9.0, and Red Hat 9.0.  In
+fact, it should work on any RPM-based Linux distribution based on
+<literal>glibc</literal> 2.3 or later.</para>

-    <para>
-      Once downloaded, the RPMs can be installed or upgraded using
-      <command>rpm -U</command>.  For example,
-    </para>
+<para>Once downloaded, the RPMs can be installed or upgraded using
+<command>rpm -U</command>.  For example,

-    <screen>
-rpm -U nix-0.5pre664-1.i386.rpm</screen>
+<screen>
+$ rpm -U nix-0.5pre664-1.i386.rpm</screen>

-    <para>
-      The RPMs install into the directory <filename>/nix</filename>.
-      Nix can be uninstalled using <command>rpm -e nix</command>.
-      After this it will be necessary to manually remove the Nix store
-      and other auxiliary data:
-    </para>
+</para>

-    <screen>
-rm -rf /nix/store
-rm -rf /nix/var</screen>
+<para>The RPMs install into the directory <filename>/nix</filename>.
+Nix can be uninstalled using <command>rpm -e nix</command>.  After
+this it will be necessary to manually remove the Nix store and other
+auxiliary data:

-  </sect1>
+<screen>
+$ rm -rf /nix/store
+$ rm -rf /nix/var</screen>

-  <sect1>
-    <title>Permissions</title>
+</para>

-    <para>
-      All Nix operations must be performed under the user ID that owns
-      the Nix store and database
-      (<filename><replaceable>prefix</replaceable>/store</filename>
-      and
-      <filename><replaceable>prefix</replaceable>/var/nix/db</filename>,
-      respectively).  When installed from the RPM packages, these
-      directories are owned by <systemitem
-      class='username'>root</systemitem>.
-    </para>
+</section>

-  </sect1>

-  <sect1>
-    <title>Using Nix</title>
+<section><title>Upgrading Nix through Nix</title>

-    <para>
-      To use Nix, some environment variables should be set.  In
-      particular, <envar>PATH</envar> should contain the directories
-      <filename><replaceable>prefix</replaceable>/bin</filename> and
-      <filename>~/.nix-profile/bin</filename>.  The first directory
-      contains the Nix tools themselves, while
-      <filename>~/.nix-profile</filename> is a symbolic link to the
-      current <emphasis>user environment</emphasis> (an automatically
-      generated package consisting of symlinks to installed packages).
-      The simplest way to set the required environment variables is to
-      include the file
-      <filename><replaceable>prefix</replaceable>/etc/profile.d/nix.sh</filename>
-      in your <filename>~/.bashrc</filename> (or similar), like this:
-    </para>
+<para>You can install the latest stable version of Nix through Nix
+itself by subscribing to the channel <link
+xlink:href="http://nix.cs.uu.nl/dist/nix/channels-v3/nix-stable" />,
+or the latest unstable version by subscribing to the channel <link
+xlink:href="http://nix.cs.uu.nl/dist/nix/channels-v3/nix-unstable" />.
+You can also do a <link linkend="sec-one-click">one-click
+installation</link> by clicking on the package links at <link
+xlink:href="http://nix.cs.uu.nl/dist/nix/" />.</para>

-    <screen>
-. <replaceable>prefix</replaceable>/etc/profile.d/nix.sh</screen>
+</section>
+
+
+<section><title>Security</title>
+
+<para>Nix has two basic security models.  First, it can be used in
+“single-user mode”, which is similar to what most other package
+management tools do: there is a single user (typically <systemitem
+class="username">root</systemitem>) who performs all package
+management operations.  All other users can then use the installed
+packages, but they cannot perform package management operations
+themselves.</para>
+
+<para>Alternatively, you can configure Nix in “multi-user mode”.  In
+this model, all users can perform package management operations — for
+instance, every user can install software without requiring root
+privileges.  Nix ensures that this is secure.  For instance, it’s not
+possible for one user to overwrite a package used by another user with
+a Trojan horse.</para>
+
+
+<section><title>Single-user mode</title>
+  
+<para>In single-user mode, all Nix operations that access the database
+in <filename><replaceable>prefix</replaceable>/var/nix/db</filename>
+or modify the Nix store in
+<filename><replaceable>prefix</replaceable>/store</filename> must be
+performed under the user ID that owns those directories.  This is
+typically <systemitem class="username">root</systemitem>.  (If you
+install from RPM packages, that’s in fact the default ownership.)
+However, on single-user machines, it is often convenient to
+<command>chown</command> those directories to your normal user account
+so that you don’t have to <command>su</command> to <systemitem
+class="username">root</systemitem> all the time.</para>
+
+</section>
+
+
+<section xml:id="ssec-multi-user"><title>Multi-user mode</title>
+
+<para>To allow a Nix store to be shared safely among multiple users,
+it is important that users are not able to run builders that modify
+the Nix store or database in arbitrary ways, or that interfere with
+builds started by other users.  If they could do so, they could
+install a Trojan horse in some package and compromise the accounts of
+other users.</para>
+
+<para>To prevent this, the Nix store and database are owned by some
+privileged user (usually <literal>root</literal>) and builders are
+executed under special user accounts (usually named
+<literal>nixbld1</literal>, <literal>nixbld2</literal>, etc.).  When a
+unprivileged user runs a Nix command, actions that operate on the Nix
+store (such as builds) are forwarded to a <emphasis>Nix
+daemon</emphasis> running under the owner of the Nix store/database
+that performs the operation.</para>
+
+<note><para>Multi-user mode has one important limitation: only
+<systemitem class="username">root</systemitem> can run <command
+linkend="sec-nix-pull">nix-pull</command> to register the availability
+of pre-built binaries.  However, those registrations are shared by all
+users, so they still get the benefit from <command>nix-pull</command>s
+done by <systemitem class="username">root</systemitem>.</para></note>
+
+
+<section><title>Setting up the build users</title>
+
+<para>The <emphasis>build users</emphasis> are the special UIDs under
+which builds are performed.  They should all be members of the
+<emphasis>build users group</emphasis> (usually called
+<literal>nixbld</literal>).  This group should have no other members.
+The build users should not be members of any other group.</para>
+
+<para>Here is a typical <filename>/etc/group</filename> definition of
+the build users group with 10 build users:
+
+<programlisting>
+nixbld:!:30000:nixbld1,nixbld2,nixbld3,nixbld4,nixbld5,nixbld6,nixbld7,nixbld8,nixbld9,nixbld10
+</programlisting>
+
+In this example the <literal>nixbld</literal> group has UID 30000, but
+of course it can be anything that doesn’t collide with an existing
+group.</para>
+
+<para>Here is the corresponding part of
+<filename>/etc/passwd</filename>:
+
+<programlisting>
+nixbld1:x:30001:65534:Nix build user 1:/var/empty:/noshell
+nixbld2:x:30002:65534:Nix build user 2:/var/empty:/noshell
+nixbld3:x:30003:65534:Nix build user 3:/var/empty:/noshell
+...
+nixbld10:x:30010:65534:Nix build user 10:/var/empty:/noshell
+</programlisting>
+
+The home directory of the build users should not exist or should be an
+empty directory to which they do not have write access.</para>
+
+<para>The build users should have write access to the Nix store, but
+they should not have the right to delete files.  Thus the Nix store’s
+group should be the build users group, and it should have the sticky
+bit turned on (like <filename>/tmp</filename>):
+
+<screen>
+$ chgrp nixbld /nix/store
+$ chmod 1777 /nix/store
+</screen>
+
+</para>
+
+<para>Finally, you should tell Nix to use the build users by
+specifying the build users group in the <link
+linkend="conf-build-users-group"><literal>build-users-group</literal>
+option</link> in the <link linkend="sec-conf-file">Nix configuration
+file</link> (<literal>/nix/etc/nix/nix.conf</literal>):
+
+<programlisting>
+build-users-group = nixbld
+</programlisting>
+
+</para>
+
+</section>
+
+
+<section><title>Nix store/database owned by root</title>
+
+<para>The simplest setup is to let <literal>root</literal> own the Nix
+store and database.  I.e.,
+
+<screen>
+$ chown -R root /nix/store /nix/var/nix</screen>
+
+</para>
+
+<para>The Nix daemon should be started as follows (as
+<literal>root</literal>):
+
+<screen>
+$ nix-worker --daemon</screen>
+
+You’ll want to put that line somewhere in your system’s boot
+scripts.</para>
+
+<para>To let unprivileged users use the daemon, they should set the
+<link linkend="envar-remote"><envar>NIX_REMOTE</envar> environment
+variable</link> to <literal>daemon</literal>.  So you should put a
+line like
+
+<programlisting>
+export NIX_REMOTE=daemon</programlisting>
+
+into the users’ login scripts.</para>
+
+</section>
+
+
+<section><title>Nix store/database not owned by root</title>
+
+<para>It is also possible to let the Nix store and database be owned
+by a non-root user, which should be more secure<footnote><para>Note
+however that even when the Nix daemon runs as root, not
+<emphasis>that</emphasis> much code is executed as root: Nix
+expression evaluation is performed by the calling (unprivileged) user,
+and builds are performed under the special build user accounts.  So
+only the code that accesses the database and starts builds is executed
+as <literal>root</literal>.</para></footnote>.  Typically, this user
+is a special account called <literal>nix</literal>, but it can be
+named anything.  It should own the Nix store and database:
+
+<screen>
+$ chown -R root /nix/store /nix/var/nix</screen>
+
+and of course <command>nix-worker --daemon</command> should be started
+under that user, e.g.,
+
+<screen>
+$ su - nix -c "exec /nix/bin/nix-worker --daemon"</screen>
+
+</para>
+
+<para>There is a catch, though: non-<literal>root</literal> users
+cannot start builds under the build user accounts, since the
+<function>setuid</function> system call is obviously privileged.  To
+allow a non-<literal>root</literal> Nix daemon to use the build user
+feature, it calls a setuid-root helper program,
+<command>nix-setuid-helper</command>.  This program is installed in
+<filename><replaceable>prefix</replaceable>/libexec/nix-setuid-helper</filename>.
+To set the permissions properly (Nix’s <command>make install</command>
+doesn’t do this, since we don’t want to ship setuid-root programs
+out-of-the-box):
+
+<screen>
+$ chown root.root /nix/libexec/nix-setuid-helper
+$ chmod 4755 /nix/libexec/nix-setuid-helper
+</screen>
+
+(This example assumes that the Nix binaries are installed in
+<filename>/nix</filename>.)</para>
+
+<para>Of course, the <command>nix-setuid-helper</command> command
+should not be usable by just anybody, since then anybody could run
+commands under the Nix build user accounts.  For that reason there is
+a configuration file <filename>/etc/nix-setuid.conf</filename> that
+restricts the use of the helper.  This file should be a text file
+containing precisely two lines, the first being the Nix daemon user
+and the second being the build users group, e.g.,
+
+<programlisting>
+nix
+nixbld
+</programlisting>
+
+The setuid-helper barfs if it is called by a user other than the one
+specified on the first line, or if it is asked to execute a build
+under a user who is not a member of the group specified on the second
+line.  The file <filename>/etc/nix-setuid.conf</filename> must be
+owned by root, and must not be group- or world-writable.  The
+setuid-helper barfs if this is not the case.</para>
+
+</section>
+
+
+<section><title>Restricting access</title>
+
+<para>To limit which users can perform Nix operations, you can use the
+permissions on the directory
+<filename>/nix/var/nix/daemon-socket</filename>.  For instance, if you
+want to restrict the use of Nix to the members of a group called
+<literal>nix-users</literal>, do
+
+<screen>
+$ chgrp nix-users /nix/var/nix/daemon-socket
+$ chmod ug=rwx,o= /nix/var/nix/daemon-socket
+</screen>
+
+This way, users who are not in the <literal>nix-users</literal> group
+cannot connect to the Unix domain socket
+<filename>/nix/var/nix/daemon-socket/socket</filename>, so they cannot
+perform Nix operations.</para>
+
+</section>
+
+
+</section> <!-- end of multi-user -->
+
+
+</section> <!-- end of security -->
+
+
+<section><title>Using Nix</title>
+
+<para>To use Nix, some environment variables should be set.  In
+particular, <envar>PATH</envar> should contain the directories
+<filename><replaceable>prefix</replaceable>/bin</filename> and
+<filename>~/.nix-profile/bin</filename>.  The first directory contains
+the Nix tools themselves, while <filename>~/.nix-profile</filename> is
+a symbolic link to the current <emphasis>user environment</emphasis>
+(an automatically generated package consisting of symlinks to
+installed packages).  The simplest way to set the required environment
+variables is to include the file
+<filename><replaceable>prefix</replaceable>/etc/profile.d/nix.sh</filename>
+in your <filename>~/.bashrc</filename> (or similar), like this:</para>
+
+<screen>
+source <replaceable>prefix</replaceable>/etc/profile.d/nix.sh</screen>
+
+</section>

-  </sect1>

 </chapter>
--- a/doc/manual/introduction.xml
+++ b/doc/manual/introduction.xml
@@ -1,93 +1,336 @@
-<chapter>
-  <title>Introduction</title>
+<chapter xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id="chap-introduction">

-  <epigraph>
-    <para><quote>The number of Nix installations in the world has grown to 5,
-        with more expected.</quote></para>
-  </epigraph>
+<title>Introduction</title>

-  <para>
-    Nix is a system for software deployment.  It supports the
-    creation and distribution of software packages, as well as the installation
-    and subsequent management of these on target machines (i.e., it is also a
-    package manager).
-  </para>

-  <para>
-    Nix solves some large problems that exist in most current deployment and
-    package management systems.  <emphasis>Dependency determination</emphasis>
-    is a big one: the correct installation of a software component requires
-    that all dependencies of that component (i.e., other components used by it)
-    are also installed.  Most systems have no way to verify that the specified
-    dependencies of a component are actually sufficient.
-  </para>
+<section><title>About Nix</title>

-  <para>
-    Another big problem is the lack of support for concurrent availability of
-    multiple <emphasis>variants</emphasis> of a component.  It must be possible
-    to have several versions of a component installed at the same time, or
-    several instances of the same version built with different parameters.
-    Unfortunately, components are in general not properly isolated from each
-    other.  For instance, upgrading a component that is a dependency for some
-    other component might break the latter.
-  </para>
+<para>Nix is a <emphasis>purely functional package manager</emphasis>.
+This means that it treats packages like values in purely functional
+programming languages such as Haskell — they are built by functions
+that don’t have side-effects, and they never change after they have
+been built.  Nix stores packages in the <emphasis>Nix
+store</emphasis>, usually the directory
+<filename>/nix/store</filename>, where each package has its own unique
+subdirectory such as

-  <para>
-    Nix solves these problems by building and storing packages in paths that
-    are infeasible to predict in advance.  For example, the artifacts of a
-    package <literal>X</literal> might be stored in
-    <filename>/nix/store/d58a0606ed616820de291d594602665d-X</filename>, rather
-    than in, say, <filename>/usr/lib</filename>.  The path component
-    <filename>d58a...</filename> is actually a cryptographic hash of all the
-    inputs (i.e., sources, requisites, and build flags) used in building
-    <literal>X</literal>, and as such is very fragile: any change to the inputs
-    will change the hash.  Therefore it is not sensible to
-    <emphasis>hard-code</emphasis> such a path into the build scripts of a
-    package <literal>Y</literal> that uses <literal>X</literal> (as does happen
-    with <quote>fixed</quote> paths such as <filename>/usr/lib</filename>).
-    Rather, the build script of package <literal>Y</literal> is parameterised
-    with the actual location of <literal>X</literal>, which is supplied by the
-    Nix system.
-  </para>
+<programlisting>
+/nix/store/r8vvq9kq18pz08v249h8my6r9vs7s0n3-firefox-2.0.0.1/
+</programlisting>

-  <para>
-    As stated above, the path name of a file system object contain a
-    cryptographic hash of all inputs involved in building it.  A change to any
-    of the inputs will cause the hash to change--and by extension, the path
-    name.  These inputs include both sources (variation in time) and
-    configuration options (variation in space).  Therefore variants of the same
-    package don't clash---they can co-exist peacefully within the same file
-    system.
-  </para>
+where <literal>r8vvq9kq…</literal> is a unique identifier for the
+package that captures all its dependencies (it’s a cryptographic hash
+of the package’s build dependency graph).  This enables many powerful
+features.</para>

-  <para>
-    Other features:
-  </para>

-  <para>
-    <emphasis>Transparent source/binary deployment.</emphasis>
-  </para>
+<simplesect><title>Multiple versions</title>

-  <para>
-    <emphasis>Unambiguous identification of configuration.</emphasis>
-  </para>
+<para>You can have multiple versions or variants of a package
+installed at the same time.  This is especially important when
+different applications have dependencies on different versions of the
+same package — it prevents the “DLL hell”.  Because of the hashing
+scheme, different versions of a package end up in different paths in
+the Nix store, so they don’t interfere with each other.</para>

-  <para>
-    <emphasis>Automatic storage management.</emphasis>
-  </para>
+<para>An important consequence is that operations like upgrading or
+uninstalling an application cannot break other applications, since
+these operations never “destructively” update or delete files that are
+used by other packages.</para>

-  <para>
-    <emphasis>Atomic upgrades and rollbacks.</emphasis>
-  </para>
+</simplesect>

-  <para>
-    <emphasis>Support for many simultaneous configurations.</emphasis>
-  </para>

-  <para>
-    <emphasis>Portability.</emphasis>  Nix is quite portable.  Contrary to
-    build systems like those in, e.g., Vesta and ClearCase, it does not rely on
-    operating system extensions.
-  </para>
+<simplesect><title>Complete dependencies</title>
+
+<para>Nix helps you make sure that package dependency specifications
+are complete.  In general, when you’re making a package for a package
+management system like RPM, you have to specify for each package what
+its dependencies are, but there are no guarantees that this
+specification is complete.  If you forget a dependency, then the
+package will build and work correctly on <emphasis>your</emphasis>
+machine if you have the dependency installed, but not on the end
+user's machine if it's not there.</para>
+
+<para>Since Nix on the other hand doesn’t install packages in “global”
+locations like <filename>/usr/bin</filename> but in package-specific
+directories, the risk of incomplete dependencies is greatly reduced.
+This is because tools such as compilers don’t search in per-packages
+directories such as
+<filename>/nix/store/5lbfaxb722zp…-openssl-0.9.8d/include</filename>,
+so if a package builds correctly on your system, this is because you
+specified the dependency explicitly.</para>
+
+<para>Runtime dependencies are found by scanning binaries for the hash
+parts of Nix store paths (such as <literal>r8vvq9kq…</literal>).  This
+sounds risky, but it works extremely well.</para>
+
+</simplesect>
+
+
+<simplesect><title>Multi-user support</title>
+
+<para>Starting at version 0.11, Nix has multi-user support.  This
+means that non-privileged users can securely install software.  Each
+user can have a different <emphasis>profile</emphasis>, a set of
+packages in the Nix store that appear in the user’s
+<envar>PATH</envar>.  If a user installs a package that another user
+has already installed previously, the package won’t be built or
+downloaded a second time.  At the same time, it is not possible for
+one user to inject a Trojan horse into a package that might be used by
+another user.</para>
+
+<!--
+<para>More details can be found in Section 3 of our <a
+href="docs/papers.html#securesharing">ASE 2005 paper</a>.</para>
+-->
+
+</simplesect>
+
+
+<simplesect><title>Atomic upgrades and rollbacks</title>
+
+<para>Since package management operations never overwrite packages in
+the Nix store but just add new versions in different paths, they are
+<emphasis>atomic</emphasis>.  So during a package upgrade, there is no
+time window in which the package has some files from the old version
+and some files from the new version — which would be bad because a
+program might well crash if it’s started during that period.</para>
+
+<para>And since package aren’t overwritten, the old versions are still
+there after an upgrade.  This means that you can <emphasis>roll
+back</emphasis> to the old version:</para>
+
+<screen>
+$ nix-env --upgrade <replaceable>some-packages</replaceable>
+$ nix-env --rollback
+</screen>
+
+</simplesect>
+
+
+<simplesect><title>Garbage collection</title>
+
+<para>When you install a package like this…
+
+<screen>
+$ nix-env --uninstall firefox
+</screen>
+
+the package isn’t deleted from the system right away (after all, you
+might want to do a rollback, or it might be in the profiles of other
+users).  Instead, unused packages can be deleted safely by running the
+<emphasis>garbage collector</emphasis>:
+
+<screen>
+$ nix-collect-garbage
+</screen>
+
+This deletes all packages that aren’t in use by any user profile or by
+a currently running program.</para>
+
+</simplesect>
+
+
+<simplesect><title>Functional package language</title>
+
+<para>Packages are built from <emphasis>Nix expressions</emphasis>,
+which is a simple functional language.  A Nix expression describes
+everything that goes into a package build action (a “derivation”):
+other packages, sources, the build script, environment variables for
+the build script, etc.  Nix tries very hard to ensure that Nix
+expressions are <emphasis>deterministic</emphasis>: building a Nix
+expression twice should yield the same result.</para>
+
+<para>Because it’s a functional language, it’s easy to support
+building variants of a package: turn the Nix expression into a
+function and call it any number of times with the appropriate
+arguments.  Due to the hashing scheme, variants don’t conflict with
+each other in the Nix store.</para>
+
+</simplesect>
+
+
+<simplesect><title>Transparent source/binary deployment</title>
+
+<para>Nix expressions generally describe how to build a package from
+source, so an installation action like
+
+<screen>
+$ nix-env --install firefox
+</screen>
+
+<emphasis>could</emphasis> cause quite a bit of build activity, as not
+only Firefox but also all its dependencies (all the way up to the C
+library and the compiler) would have to built, at least if they are
+not already in the Nix store.  This is a <emphasis>source deployment
+model</emphasis>.  For most users, building from source is not very
+pleasant as it takes far too long.  However, Nix can automatically
+skip building from source and download a pre-built binary instead if
+it knows about it.  <emphasis>Nix channels</emphasis> provide Nix
+expressions along with pre-built binaries.</para>
+
+<!--
+<para>source deployment model (like <a
+href="http://www.gentoo.org/">Gentoo</a>) and a binary model (like
+RPM)</para>
+-->
+
+</simplesect>
+
+
+<simplesect><title>Binary patching</title>
+
+<para>In addition to downloading binaries automatically if they’re
+available, Nix can download binary deltas that patch an existing
+package in the Nix store into a new version.  This speeds up
+upgrades.</para>
+
+</simplesect>
+
+
+<simplesect><title>Nix Packages collection</title>
+
+<para>We provide a large set of Nix expressions containing hundreds of
+existing Unix packages, the <emphasis>Nix Packages
+collection</emphasis> (Nixpkgs).</para>
+
+</simplesect>
+
+
+<simplesect><title>Service deployment</title>
+
+<para>Nix can be used not only for rolling out packages, but also
+complete <emphasis>configurations</emphasis> of services.  This is
+done by treating all the static bits of a service (such as software
+packages, configuration files, control scripts, static web pages,
+etc.) as “packages” that can be built by Nix expressions.  As a
+result, all the features above apply to services as well: for
+instance, you can roll back a web server configuration if a
+configuration change turns out to be undesirable, you can easily have
+multiple instances of a service (e.g., a test and production server),
+and because the whole service is built in a purely functional way from
+a Nix expression, it is repeatable so you can easily reproduce the
+service on another machine.</para>
+
+<!--
+<para>You can read more about this in our <a
+href="docs/papers.html#servicecm">SCM-12 paper</a>.</para>
+-->
+
+</simplesect>
+
+
+<simplesect><title>Portability</title>
+
+<para>Nix should run on most Unix systems, including Linux, FreeBSD and
+Mac OS X.  It is also supported on Windows using Cygwin.</para>
+
+</simplesect>
+
+
+<simplesect><title>NixOS</title>
+
+<para>NixOS is a Linux distribution based on Nix.  It uses Nix not
+just for package management but also to manage the system
+configuration (e.g., to build configuration files in
+<filename>/etc</filename>).  This means, among other things, that it’s
+possible to easily roll back the entire configuration of the system to
+an earlier state.  Also, users can install software without root
+privileges.  For more information and downloads, see the <link
+xlink:href="http://nix.cs.uu.nl/nixos/">NixOS homepage</link>.</para>
+
+</simplesect>
+
+
+<!-- other features:
+
+- build farms
+- reproducibility (Nix expressions allows whole configuration to be rebuilt)
+
+-->
+
+</section>
+
+
+<section><title>About us</title>
+
+<para>Nix was developed at the <link
+xlink:href="http://www.cs.uu.nl/">Department of Information and
+Computing Sciences</link>, Utrecht University by the <link
+xlink:href="http://www.cs.uu.nl/wiki/Trace/WebHome">TraCE
+project</link>.  The project is funded by the Software Engineering
+Research Program <link
+xlink:href="http://www.jacquard.nl/">Jacquard</link> to improve the
+support for variability in software systems.</para>
+
+</section>
+
+
+<section><title>About this manual</title>
+
+<para>This manual tells you how to install and use Nix and how to
+write Nix expressions for software not already in the Nix Packages
+collection.  It also discusses some advanced topics, such as setting
+up a Nix-based build farm.</para>
+
+</section>
+
+
+<section><title>License</title>
+
+<para>Nix is free software; you can redistribute it and/or modify it
+under the terms of the <link
+xlink:href="http://www.gnu.org/licenses/lgpl.html">GNU Lesser General
+Public License</link> as published by the <link
+xlink:href="http://www.fsf.org/">Free Software Foundation</link>;
+either version 2.1 of the License, or (at your option) any later
+version.  Nix is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.</para>
+
+</section>
+
+
+<section><title>More information</title>
+
+<para>Some background information on Nix can be found in a number of
+papers.  The ICSE 2004 paper <citetitle
+xlink:href='http://www.cs.uu.nl/~eelco/pubs/immdsd-icse2004-final.pdf'>Imposing
+a Memory Management Discipline on Software Deployment</citetitle>
+discusses the hashing mechanism used to ensure reliable dependency
+identification and non-interference between different versions and
+variants of packages.  The LISA 2004 paper <citetitle
+xlink:href='http://www.cs.uu.nl/~eelco/pubs/nspfssd-lisa2004-final.pdf'>Nix:
+A Safe and Policy-Free System for Software Deployment</citetitle>
+gives a more general discussion of Nix from a system-administration
+perspective.  The CBSE 2005 paper <citetitle
+xlink:href='http://www.cs.uu.nl/~eelco/pubs/eupfcdm-cbse2005-final.pdf'>Efficient
+Upgrading in a Purely Functional Component Deployment Model
+</citetitle> is about transparent patch deployment in Nix.  The SCM-12
+paper <citetitle
+xlink:href='http://www.cs.uu.nl/~eelco/pubs/servicecm-scm12-final.pdf'>
+Service Configuration Management</citetitle> shows how services (e.g.,
+web servers) can be deployed and managed through Nix.  A short
+overview of NixOS is given in the HotOS XI paper <citetitle
+xlink:href="http://www.cs.uu.nl/~eelco/pubs/hotos-final.pdf">Purely
+Functional System Configuration Management</citetitle>.  The Nix
+homepage has <link
+xlink:href="http://nix.cs.uu.nl/docs/papers.html">an up-to-date list
+of Nix-related papers</link>.</para>
+
+<para>Nix is the subject of Eelco Dolstra’s PhD thesis <citetitle
+xlink:href="http://igitur-archive.library.uu.nl/dissertations/2006-0118-200031/index.htm">The
+Purely Functional Software Deployment Model</citetitle>, which
+contains most of the papers listed above.</para>
+
+<para>Nix has a homepage at <link
+xlink:href="http://nix.cs.uu.nl/"/>.</para>
+
+</section>
+

 </chapter>
--- a/doc/manual/manual.xml
+++ b/doc/manual/manual.xml
@@ -1,86 +1,125 @@
-<?xml version="1.0"?>
-<!DOCTYPE book
-    PUBLIC "-//OASIS//DTD DocBook EBNF Module V1.0//EN"
-    "http://www.oasis-open.org/docbook/xml/ebnf/1.0/dbebnf.dtd"
-[
-<!-- <!DOCTYPE book
-    PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
-    "http://www.docbook.org/xml/4.3/docbook-xml-4.3.zip" -->
-<!ENTITY introduction SYSTEM "introduction.xml">
-<!ENTITY quick-start SYSTEM "quick-start.xml">
-<!ENTITY installation SYSTEM "installation.xml">
-<!ENTITY overview SYSTEM "overview.xml">
-<!ENTITY opt-common SYSTEM "opt-common.xml">
-<!ENTITY opt-common-syn SYSTEM "opt-common-syn.xml">
-<!ENTITY nix-env SYSTEM "nix-env.xml">
-<!ENTITY nix-store SYSTEM "nix-store.xml">
-<!ENTITY nix-instantiate SYSTEM "nix-instantiate.xml">
-<!ENTITY nix-collect-garbage SYSTEM "nix-collect-garbage.xml">
-<!ENTITY nix-push SYSTEM "nix-push.xml">
-<!ENTITY nix-pull SYSTEM "nix-pull.xml">
-<!ENTITY nix-prefetch-url SYSTEM "nix-prefetch-url.xml">
-<!ENTITY nix-lang-ref SYSTEM "nix-lang-ref.xml">
-<!ENTITY troubleshooting SYSTEM "troubleshooting.xml">
-<!ENTITY bugs SYSTEM "bugs.xml">
-<!ENTITY version SYSTEM "version.xml">
-]>
+<book xmlns="http://docbook.org/ns/docbook"
+      xmlns:xi="http://www.w3.org/2001/XInclude">

-<book>
-  <title>Nix: A System for Software Deployment</title>
+  <info>
+
+    <title>Nix User's Guide</title>
+
+    <subtitle>Draft (Version <xi:include href="version.txt"
+    parse="text" />)</subtitle>

-  <subtitle>Draft (Version &version;)</subtitle>
-  
-  <bookinfo>
    <author>
-      <firstname>Eelco</firstname>
-      <surname>Dolstra</surname>
+      <personname>
+        <firstname>Eelco</firstname>
+        <surname>Dolstra</surname>
+      </personname>
+      <affiliation>
+        <orgname>Utrecht University</orgname>
+        <orgdiv>Faculty of Science, Department of Information and Computing Sciences</orgdiv>
+      </affiliation>
    </author>
+
    <copyright>
      <year>2004</year>
+      <year>2005</year>
+      <year>2006</year>
+      <year>2007</year>
      <holder>Eelco Dolstra</holder>
    </copyright>
-  </bookinfo>

-  &introduction;
-  &quick-start;
-  &installation;
-  &overview;
+    <date>September 2007</date>
+    
+  </info>
+
+  
+  <xi:include href="introduction.xml" />
+  <xi:include href="quick-start.xml" />
+  <xi:include href="installation.xml" />
+  <xi:include href="package-management.xml" />
+  <xi:include href="writing-nix-expressions.xml" />
+  <xi:include href="build-farm.xml" />
+

  <appendix>
    <title>Command Reference</title>
-    <sect1>
-      <title>nix-env</title>
-      &nix-env;
-    </sect1>
-    <sect1>
-      <title>nix-store</title>
-      &nix-store;
-    </sect1>
-    <sect1>
-      <title>nix-instantiate</title>
-      &nix-instantiate;
-    </sect1>
-    <sect1>
-      <title>nix-collect-garbage</title>
-      &nix-collect-garbage;
-    </sect1>
-    <sect1>
-      <title>nix-push</title>
-      &nix-push;
-    </sect1>
-    <sect1>
-      <title>nix-pull</title>
-      &nix-pull;
-    </sect1>
-    <sect1>
-      <title>nix-prefetch-url</title>
-      &nix-prefetch-url;
-    </sect1>
+    <xi:include href="opt-common.xml" />
+    <xi:include href="env-common.xml" />
+    <xi:include href="conf-file.xml" />
+    
+    <section>
+      <title>Main commands</title>
+      <section xml:id="sec-nix-env">
+        <title>nix-env</title>
+        <xi:include href="nix-env.xml" />
+      </section>
+      <section xml:id="sec-nix-instantiate">
+        <title>nix-instantiate</title>
+        <xi:include href="nix-instantiate.xml" />
+      </section>
+      <section xml:id="sec-nix-store">
+        <title>nix-store</title>
+        <xi:include href="nix-store.xml" />
+      </section>
+    </section>
+    
+    <section>
+      <title>Utilities</title>
+      <section xml:id="sec-nix-build">
+        <title>nix-build</title>
+        <xi:include href="nix-build.xml" />
+      </section>
+      <section xml:id="sec-nix-channel">
+        <title>nix-channel</title>
+        <xi:include href="nix-channel.xml" />
+      </section>
+      <section xml:id="sec-nix-collect-garbage">
+        <title>nix-collect-garbage</title>
+        <xi:include href="nix-collect-garbage.xml" />
+      </section>
+      <section xml:id="sec-nix-copy-closure">
+        <title>nix-copy-closure</title>
+        <xi:include href="nix-copy-closure.xml" />
+      </section>
+      <section xml:id="sec-nix-hash">
+        <title>nix-hash</title>
+        <xi:include href="nix-hash.xml" />
+      </section>
+      <section xml:id="sec-nix-install-package">
+        <title>nix-install-package</title>
+        <xi:include href="nix-install-package.xml" />
+      </section>
+      <section xml:id="sec-nix-pack-closure">
+        <title>nix-pack-closure</title>
+        <xi:include href="nix-pack-closure.xml" />
+      </section>
+      <section xml:id="sec-nix-prefetch-url">
+        <title>nix-prefetch-url</title>
+        <xi:include href="nix-prefetch-url.xml" />
+      </section>
+      <section xml:id="sec-nix-pull">
+        <title>nix-pull</title>
+        <xi:include href="nix-pull.xml" />
+      </section>
+      <section xml:id="sec-nix-push">
+        <title>nix-push</title>
+        <xi:include href="nix-push.xml" />
+      </section>
+      <section xml:id="sec-nix-unpack-closure">
+        <title>nix-unpack-closure</title>
+        <xi:include href="nix-unpack-closure.xml" />
+      </section>
+    </section>
+    
  </appendix>

-  &nix-lang-ref;
-
-  &troubleshooting;
-  &bugs;
+  <xi:include href="troubleshooting.xml" />
+  <xi:include href="bugs.xml" />
+  <xi:include href="glossary.xml" />

+  <appendix>
+    <title>Nix Release Notes</title>
+    <xi:include href="release-notes.xml"
+                xpointer="xmlns(x=http://docbook.org/ns/docbook)xpointer(x:article/x:section)" />
+  </appendix>
+    
 </book>
--- a/doc/manual/nix-build.xml
+++ b/doc/manual/nix-build.xml
@@ -0,0 +1,145 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+
+<refmeta>
+  <refentrytitle>nix-build</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-build</refname>
+  <refpurpose>build a Nix expression</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-build</command>
+    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="opt-common-syn.xml#xmlns(db=http://docbook.org/ns/docbook)xpointer(/db:nop/*)" />
+    <arg><option>--arg</option> <replaceable>name</replaceable> <replaceable>value</replaceable></arg>
+    <arg><option>--argstr</option> <replaceable>name</replaceable> <replaceable>value</replaceable></arg>
+    <arg>
+      <group choice='req'>
+        <arg choice='plain'><option>--attr</option></arg>
+        <arg choice='plain'><option>-A</option></arg>
+      </group>
+      <replaceable>attrPath</replaceable>
+    </arg>
+    <arg><option>--add-drv-link</option></arg>
+    <arg><option>--drv-link </option><replaceable>drvlink</replaceable></arg>
+    <arg><option>--no-out-link</option></arg>
+    <arg>
+      <group choice='req'>
+        <arg choice='plain'><option>--out-link</option></arg>
+        <arg choice='plain'><option>-o</option></arg>
+      </group>
+      <replaceable>outlink</replaceable>
+    </arg>
+    <arg choice='plain' rep='repeat'><replaceable>paths</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+<refsection><title>Description</title>
+
+<para>The <command>nix-build</command> command builds the derivations
+described by the Nix expressions in <replaceable>paths</replaceable>.
+If the build succeeds, it places a symlink to the result in the
+current directory.  The symlink is called <filename>result</filename>.
+If there are multiple Nix expressions, or the Nix expressions evaluate
+to multiple derivations, multiple sequentially numbered symlinks are
+created (<filename>result</filename>, <filename>result-2</filename>,
+and so on).</para>
+
+<para>If no <replaceable>paths</replaceable> are specified, then
+<command>nix-build</command> will use <filename>default.nix</filename>
+in the current directory, if it exists.</para>
+
+<para><command>nix-build</command> is essentially a wrapper around
+<link
+linkend="sec-nix-instantiate"><command>nix-instantiate</command></link>
+(to translate a high-level Nix expression to a low-level store
+derivation) and <link
+linkend="rsec-nix-store-realise"><command>nix-store
+--realise</command></link> (to build the store derivation).</para>
+
+<warning><para>The result of the build is automatically registered as
+a root of the Nix garbage collector.  This root disappears
+automatically when the <filename>result</filename> symlink is deleted
+or renamed.  So don’t rename the symlink.</para></warning>
+
+</refsection>
+
+
+<refsection><title>Options</title>
+
+<para>See also <xref linkend="sec-common-options" />.  All options not
+listed here are passed to <command>nix-store --realise</command>,
+except for <option>--arg</option> and <option>--attr</option> /
+<option>-A</option> which are passed to
+<command>nix-instantiate</command>.</para>
+
+<variablelist>
+
+  <varlistentry><term><option>--add-drv-link</option></term>
+  
+    <listitem><para>Add a symlink in the current directory to the
+    store derivation produced by <command>nix-instantiate</command>.
+    The symlink is called <filename>derivation</filename> (which is
+    numbered in the case of multiple derivations).  The derivation is
+    a root of the garbage collector until the symlink is deleted or
+    renamed.</para></listitem>
+    
+  </varlistentry>
+
+  <varlistentry><term><option>--drv-link</option> <replaceable>drvlink</replaceable></term>
+  
+    <listitem><para>Change the name of the symlink to the derivation
+    created when <option>--add-drv-link</option> is used from
+    <filename>derivation</filename> to
+    <replaceable>drvlink</replaceable>.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--no-out-link</option></term>
+  
+    <listitem><para>Do not create a symlink to the output path.  Note
+    that as a result the output does not become a root of the garbage
+    collector, and so might be deleted by <command>nix-store
+    --gc</command>.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry xml:id='opt-out-link'><term><option>--out-link</option> /
+  <option>-o</option> <replaceable>outlink</replaceable></term>
+  
+    <listitem><para>Change the name of the symlink to the output path
+    created unless <option>--no-out-link</option> is used from
+    <filename>result</filename> to
+    <replaceable>outlink</replaceable>.</para></listitem>
+
+  </varlistentry>
+
+</variablelist>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<screen>
+$ nix-build pkgs/top-level/all-packages.nix -A firefox
+store derivation is /nix/store/qybprl8sz2lc...-firefox-1.5.0.7.drv
+/nix/store/d18hyl92g30l...-firefox-1.5.0.7
+
+$ ls -l result
+lrwxrwxrwx  <replaceable>...</replaceable>  result -> /nix/store/d18hyl92g30l...-firefox-1.5.0.7
+
+$ ls ./result/bin/
+firefox  firefox-config</screen>
+
+</refsection>
+
+
+</refentry>
--- a/doc/manual/nix-channel.xml
+++ b/doc/manual/nix-channel.xml
@@ -0,0 +1,92 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+  
+<refmeta>
+  <refentrytitle>nix-channel</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-channel</refname>
+  <refpurpose>manage Nix channels</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-channel</command>
+    <group choice='req'>
+      <arg choice='plain'><option>--add</option> <replaceable>url</replaceable></arg>
+      <arg choice='plain'><option>--remove</option> <replaceable>url</replaceable></arg>
+      <arg choice='plain'><option>--list</option></arg>
+      <arg choice='plain'><option>--update</option></arg>
+    </group>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+<refsection><title>Description</title>
+
+<para>A Nix channel is mechanism that allows you to automatically stay
+up-to-date with a set of pre-built Nix expressions.  A Nix channel is
+just a URL that points to a place that contains a set of Nix
+expressions, as well as a <command>nix-push</command> manifest.  See
+also <xref linkend="sec-channels" />.</para>
+
+<para>This command has the following operations:
+
+<variablelist>
+
+  <varlistentry><term><option>--add</option> <replaceable>url</replaceable></term>
+
+    <listitem><para>Adds <replaceable>url</replaceable> to the list of
+    subscribed channels.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--remove</option> <replaceable>url</replaceable></term>
+
+    <listitem><para>Removes <replaceable>url</replaceable> from the
+    list of subscribed channels.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--list</option></term>
+
+    <listitem><para>Prints the URLs of all subscribed channels on
+    standard output.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--update</option></term>
+
+    <listitem><para>Downloads the Nix expressions of all subscribed
+    channels, makes them the default for <command>nix-env</command>
+    operations (by symlinking them in the directory
+    <filename>~/.nix-defexpr</filename>), and performs a
+    <command>nix-pull</command> on the manifests of all channels to
+    make pre-built binaries available.</para></listitem>
+
+  </varlistentry>
+
+</variablelist>
+
+</para>
+
+<para>Note that <option>--add</option> and <option>--remove</option>
+do not automatically perform an update.</para>
+
+<para>The list of subscribed channels is stored in
+<filename>~/.nix-channels</filename>.</para>
+
+<para>A channel consists of two elements: a bzipped Tar archive
+containing the Nix expressions, and a manifest created by
+<command>nix-push</command>.  These must be stored under
+<literal><replaceable>url</replaceable>/nixexprs.tar.bz2</literal> and
+<literal><replaceable>url</replaceable>/MANIFEST</literal>,
+respectively.</para>
+
+</refsection>
+
+</refentry>
--- a/doc/manual/nix-collect-garbage.xml
+++ b/doc/manual/nix-collect-garbage.xml
@@ -1,75 +1,58 @@
-<refentry>
-  <refnamediv>
-    <refname>nix-collect-garbage</refname>
-    <refpurpose>determine the set of unreachable store paths</refpurpose>
-  </refnamediv>
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+  
+<refmeta>
+  <refentrytitle>nix-collect-garbage</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>

-  <refsynopsisdiv>
-    <cmdsynopsis>
-      <command>nix-collect-garbage</command>
-      <arg><option>--invert</option></arg>
-      <arg><option>--no-successors</option></arg>
-    </cmdsynopsis>
-  </refsynopsisdiv>
+<refnamediv>
+  <refname>nix-collect-garbage</refname>
+  <refpurpose>delete unreachable store paths</refpurpose>
+</refnamediv>

-  <refsection>
-    <title>Description</title>
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-collect-garbage</command>
+    <arg><option>--delete-old</option></arg>
+    <arg><option>-d</option></arg>
+    <group choice='opt'>
+      <arg choice='plain'><option>--print-roots</option></arg>
+      <arg choice='plain'><option>--print-live</option></arg>
+      <arg choice='plain'><option>--print-dead</option></arg>
+      <arg choice='plain'><option>--delete</option></arg>
+    </group>
+  </cmdsynopsis>
+</refsynopsisdiv>

-    <para>
-      The command <command>nix-collect-garbage</command> determines
-      the paths in the Nix store that are garbage, that is, not
-      reachable from outside of the store.  These paths can be safely
-      deleted without affecting the integrity of the system.
-    </para>
+<refsection><title>Description</title>

-  </refsection>
+<para>The command <command>nix-collect-garbage</command> is mostly an
+alias of <link linkend="rsec-nix-store-gc"><command>nix-store
+--gc</command></link>, that is, it deletes all unreachable paths in
+the Nix store to clean up your system.  However, it provides an
+additional option <option>-d</option> (<option>--delete-old</option>)
+that deletes all old generations of all profiles in
+<filename>/nix/var/nix/profiles</filename> by invoking
+<literal>nix-env --delete-generations old</literal> on all profiles.
+Of course, this makes rollbacks to previous configurations
+impossible.</para>

-  <refsection>
-    <title>Options</title>
+</refsection>

-    <variablelist>
+<refsection><title>Example</title>

-      <varlistentry>
-        <term><option>--invert</option></term>
-        <listitem>
-          <para>
-            Causes the set of <emphasis>reachable</emphasis> paths to
-            be printed, rather than the unreachable paths.  These are
-            the paths that may <emphasis>not</emphasis> be deleted.
-          </para>
-        </listitem>
-      </varlistentry>
-      
-      <varlistentry>
-        <term><option>--no-successors</option></term>
-        <listitem>
-          <para>
-            Causes <command>nix-collect-garbage</command> not to
-            follow successor relations.  By default, if a derivation
-            store expression is reachable, its successor (i.e., a
-            closure store expression) is also considered to be
-            reachable.  This option is always safe, but garbage
-            collecting successors may cause undesirable rebuilds later
-            on.
-          </para>
-        </listitem>
-      </varlistentry>
-      
-    </variablelist>
+<para>To delete from the Nix store everything that is not used by the
+current generations of each profile, do

-  </refsection>
+<screen>
+$ nix-collect-garbage -d</screen>

-  <refsection>
-    <title>Examples</title>
+</para>

-    <para>
-      To delete all unreachable paths, do the following:
-    
-      <screen>
-$ nix-collect-garbage | xargs nix-store --delete</screen>
+</refsection>

-    </para>
-
-  </refsection>
-    
 </refentry>
--- a/doc/manual/nix-copy-closure.xml
+++ b/doc/manual/nix-copy-closure.xml
@@ -0,0 +1,151 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+
+<refmeta>
+  <refentrytitle>nix-copy-closure</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-copy-closure</refname>
+  <refpurpose>copy a closure to or from a remote machine via SSH</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-copy-closure</command>
+    <group>
+      <arg choice='plain'><option>--to</option></arg>
+      <arg choice='plain'><option>--from</option></arg>
+    </group>
+    <arg><option>--sign</option></arg>
+    <arg><option>--gzip</option></arg>
+    <arg choice='plain'>
+      <arg><replaceable>user@</replaceable></arg><replaceable>machine</replaceable>
+    </arg>
+    <arg choice='plain'><replaceable>paths</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+
+<refsection><title>Description</title>
+
+<para><command>nix-copy-closure</command> gives you an easy and
+efficient way to exchange software between machines.  Given one or
+more Nix store paths <replaceable>paths</replaceable> on the local
+machine, <command>nix-copy-closure</command> computes the closure of
+those paths (i.e. all their dependencies in the Nix store), and copies
+all paths in the closure to the remote machine via the
+<command>ssh</command> (Secure Shell) command.  With the
+<option>--from</option>, the direction is reversed:
+the closure of <replaceable>paths</replaceable> on a remote machine is
+copied to the Nix store on the local machine.</para>
+
+<para>This command is efficient because it only sends the store paths
+that are missing on the target machine.</para>
+
+<para>Since <command>nix-copy-closure</command> calls
+<command>ssh</command>, you may be asked to type in the appropriate
+password or passphrase.  In fact, you may be asked
+<emphasis>twice</emphasis> because <command>nix-copy-closure</command>
+currently connects twice to the remote machine, first to get the set
+of paths missing on the target machine, and second to send the dump of
+those paths.  If this bothers you, use
+<command>ssh-agent</command>.</para>
+
+
+<refsection><title>Options</title>
+
+<variablelist>
+  
+  <varlistentry><term><option>--to</option></term>
+
+    <listitem><para>Copy the closure of
+    <replaceable>paths</replaceable> from the local Nix store to the
+    Nix store on <replaceable>machine</replaceable>.  This is the
+    default.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--from</option></term>
+
+    <listitem><para>Copy the closure of
+    <replaceable>paths</replaceable> from the Nix store on
+    <replaceable>machine</replaceable> to the local Nix
+    store.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--sign</option></term>
+
+    <listitem><para>Let the sending machine cryptographically sign the
+    dump of each path with the key in
+    <filename>/nix/etc/nix/signing-key.sec</filename>.  If the user on
+    the target machine does not have direct access to the Nix store
+    (i.e., if the target machine has a multi-user Nix installation),
+    then the target machine will check the dump against
+    <filename>/nix/etc/nix/signing-key.pub</filename> before unpacking
+    it in its Nix store.  This allows secure sharing of store paths
+    between untrusted users on two machines, provided that there is a
+    trust relation between the Nix installations on both machines
+    (namely, they have matching public/secret keys).</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--gzip</option></term>
+
+    <listitem><para>Compress the dump of each path with
+    <command>gzip</command> before sending it.</para></listitem>
+
+  </varlistentry>
+
+</variablelist>
+
+</refsection>
+
+
+<refsection><title>Environment variables</title>
+
+<variablelist>
+
+  <varlistentry><term><envar>NIX_SSHOPTS</envar></term>
+
+    <listitem><para>Additional options to be passed to
+    <command>ssh</command> on the command line.</para></listitem>
+
+  </varlistentry>
+  
+</variablelist>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<para>Copy Firefox with all its dependencies to a remote machine:
+
+<screen>
+$ nix-copy-closure alice@itchy.labs $(type -tP firefox)</screen>
+
+</para>
+
+<para>Copy Subversion from a remote machine and then install it into a
+user environment:
+
+<screen>
+$ nix-copy-closure --from alice@itchy.labs \
+    /nix/store/0dj0503hjxy5mbwlafv1rsbdiyx1gkdy-subversion-1.4.4
+$ nix-env -i /nix/store/0dj0503hjxy5mbwlafv1rsbdiyx1gkdy-subversion-1.4.4
+</screen>
+
+</para>
+
+</refsection>
+
+
+</refsection>
+
+</refentry>
--- a/doc/manual/nix-env.xml
+++ b/doc/manual/nix-env.xml
--- a/doc/manual/nix-hash.xml
+++ b/doc/manual/nix-hash.xml
@@ -0,0 +1,162 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+  
+<refmeta>
+  <refentrytitle>nix-hash</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-hash</refname>
+  <refpurpose>compute the cryptographic hash of a path</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-hash</command>
+    <arg><option>--flat</option></arg>
+    <arg><option>--base32</option></arg>
+    <arg><option>--truncate</option></arg>
+    <arg><option>--type</option> <replaceable>hashAlgo</replaceable></arg>
+    <arg choice='plain' rep='repeat'><replaceable>path</replaceable></arg>
+  </cmdsynopsis>
+  <cmdsynopsis>
+    <command>nix-hash</command>
+    <arg choice='plain'><option>--to-base16</option></arg>
+    <arg choice='plain' rep='repeat'><replaceable>hash</replaceable></arg>
+  </cmdsynopsis>
+  <cmdsynopsis>
+    <command>nix-hash</command>
+    <arg choice='plain'><option>--to-base32</option></arg>
+    <arg choice='plain' rep='repeat'><replaceable>hash</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+
+<refsection><title>Description</title>
+
+<para>The command <command>nix-hash</command> computes the
+cryptographic hash of the contents of each
+<replaceable>path</replaceable> and prints it on standard output.  By
+default, it computes an MD5 hash, but other hash algorithms are
+available as well.  The hash is printed in hexadecimal.</para>
+
+<para>The hash is computed over a <emphasis>serialisation</emphasis>
+of each path: a dump of the file system tree rooted at the path.  This
+allows directories and symlinks to be hashed as well as regular files.
+The dump is in the <emphasis>NAR format</emphasis> produced by <link
+linkend="refsec-nix-store-dump"><command>nix-store</command>
+<option>--dump</option></link>.  Thus, <literal>nix-hash
+<replaceable>path</replaceable></literal> yields the same
+cryptographic hash as <literal>nix-store --dump
+<replaceable>path</replaceable> | md5sum</literal>.</para>
+
+</refsection>
+
+
+<refsection><title>Options</title>
+
+<variablelist>
+  
+  <varlistentry><term><option>--flat</option></term>
+
+    <listitem><para>Print the cryptographic hash of the contents of
+    each regular file <replaceable>path</replaceable>.  That is, do
+    not compute the hash over the dump of
+    <replaceable>path</replaceable>.  The result is identical to that
+    produced by the GNU commands <command>md5sum</command> and
+    <command>sha1sum</command>.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--base32</option></term>
+
+    <listitem><para>Print the hash in a base-32 representation rather
+    than hexadecimal.  This base-32 representation is more compact and
+    can be used in Nix expressions (such as in calls to
+    <function>fetchurl</function>).</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--truncate</option></term>
+
+    <listitem><para>Truncate hashes longer than 160 bits (such as
+    SHA-256) to 160 bits.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--type</option> <replaceable>hashAlgo</replaceable></term>
+
+    <listitem><para>Specify a cryptographic hash, which can be one of
+    <literal>md5</literal>, <literal>sha1</literal>, and
+    <literal>sha256</literal>.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--to-base16</option></term>
+
+    <listitem><para>Don’t hash anything, but convert the base-32 hash
+    representation <replaceable>hash</replaceable> to
+    hexadecimal.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--to-base32</option></term>
+
+    <listitem><para>Don’t hash anything, but convert the hexadecimal
+    hash representation <replaceable>hash</replaceable> to
+    base-32.</para></listitem>
+
+  </varlistentry>
+
+</variablelist>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<para>Computing hashes:
+
+<screen>
+$ mkdir test
+$ echo "hello" > test/world
+
+$ nix-hash test/ <lineannotation>(MD5 hash; default)</lineannotation>
+8179d3caeff1869b5ba1744e5a245c04
+
+$ nix-store --dump test/ | md5sum <lineannotation>(for comparison)</lineannotation>
+8179d3caeff1869b5ba1744e5a245c04  -
+
+$ nix-hash --type sha1 test/
+e4fd8ba5f7bbeaea5ace89fe10255536cd60dab6
+
+$ nix-hash --type sha1 --base32 test/
+nvd61k9nalji1zl9rrdfmsmvyyjqpzg4
+
+$ nix-hash --type sha256 --flat test/
+error: reading file `test/': Is a directory
+
+$ nix-hash --type sha256 --flat test/world
+5891b5b522d5df086d0ff0b110fbd9d21bb4fc7163af34d08286a2e846f6be03</screen>
+
+</para>
+
+<para>Converting between hexadecimal and base-32:
+
+<screen>
+$ nix-hash --type sha1 --to-base32 e4fd8ba5f7bbeaea5ace89fe10255536cd60dab6
+nvd61k9nalji1zl9rrdfmsmvyyjqpzg4
+
+$ nix-hash --type sha1 --to-base16 nvd61k9nalji1zl9rrdfmsmvyyjqpzg4
+e4fd8ba5f7bbeaea5ace89fe10255536cd60dab6</screen>
+
+</para>
+
+</refsection>
+
+
+</refentry>
--- a/doc/manual/nix-install-package.xml
+++ b/doc/manual/nix-install-package.xml
@@ -0,0 +1,197 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+  
+<refmeta>
+  <refentrytitle>nix-install-package</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-install-package</refname>
+  <refpurpose>install a Nix Package file</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-install-package</command>
+    <arg><option>--non-interactive</option></arg>
+    <arg>
+      <group choice='req'>
+        <arg choice='plain'><option>--profile</option></arg>
+        <arg choice='plain'><option>-p</option></arg>
+      </group>
+      <replaceable>path</replaceable>
+    </arg>
+    <sbr />
+    <group choice='req'>
+      <arg choice='req'>
+        <option>--url</option>
+        <arg choice='plain'><replaceable>url</replaceable></arg>
+      </arg>
+      <arg choice='req'>
+        <arg choice='plain'><replaceable>file</replaceable></arg>
+      </arg>
+    </group>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+
+<refsection><title>Description</title>
+
+<para>The command <command>nix-install-package</command> interactively
+installs a Nix Package file (<filename>*.nixpkg</filename>), which is
+a small file that contains a store path to be installed along with the
+URL of a <link linkend="sec-nix-push"><command>nix-push</command>
+manifest</link>.  The Nix Package file is either
+<replaceable>file</replaceable>, or automatically downloaded from
+<replaceable>url</replaceable> if the <option>--url</option> switch is
+used.</para>
+
+<para><command>nix-install-package</command> is used in <link
+linkend="sec-one-click">one-click installs</link> to download and
+install pre-built binary packages with all necessary dependencies.
+<command>nix-install-package</command> is intended to be associated
+with the MIME type <literal>application/nix-package</literal> in a web
+browser so that it is invoked automatically when you click on
+<filename>*.nixpkg</filename> files.  When invoked, it restarts itself
+in a terminal window (since otherwise it would be invisible when run
+from a browser), asks the user to confirm whether to install the
+package, and if so downloads and installs the package into the user’s
+current profile.</para>
+
+<para>To obtain a window, <command>nix-install-package</command> tries
+to restart itself with <command>xterm</command>,
+<command>konsole</command> and
+<command>gnome-terminal</command>.</para>
+
+</refsection>
+
+
+<refsection><title>Options</title>
+
+<variablelist>
+  
+  <varlistentry><term><option>--non-interactive</option></term>
+
+    <listitem><para>Do not open a new terminal window and do not ask
+    for confirmation.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--profile</option></term>
+    <term><option>-p</option></term>
+
+    <listitem><para>Install the package into the specified profile
+    rather than the user’s current profile.</para></listitem>
+
+  </varlistentry>
+
+</variablelist>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<para>To install <filename>subversion-1.4.0.nixpkg</filename> into the
+user’s current profile, without any prompting:
+
+<screen>
+$ nix-install-package --non-interactive subversion-1.4.0.nixpkg</screen>
+
+</para>
+
+<para>To install the same package from some URL into a different
+profile:
+
+<screen>
+$ nix-install-package --non-interactive -p /nix/var/nix/profiles/eelco \
+    --url http://nix.cs.uu.nl/dist/nix/nixpkgs-0.10pre6622/pkgs/subversion-1.4.0-i686-linux.nixpkg</screen>
+
+</para>
+
+</refsection>
+
+
+<refsection><title>Format of <literal>nixpkg</literal> files</title>
+
+<para>A Nix Package file consists of a single line with the following
+format:
+
+<screen>
+NIXPKG1 <replaceable>manifestURL</replaceable> <replaceable>name</replaceable> <replaceable>system</replaceable> <replaceable>drvPath</replaceable> <replaceable>outPath</replaceable></screen>
+
+The elemens are as follows:
+
+<variablelist>
+
+  <varlistentry><term><literal>NIXPKG1</literal></term>
+  
+    <listitem><para>The version of the Nix Package
+    file.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><replaceable>manifestURL</replaceable></term>
+  
+    <listitem><para>The manifest to be pulled by
+    <command>nix-pull</command>.  The manifest must contain
+    <replaceable>outPath</replaceable>.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><replaceable>name</replaceable></term>
+  
+    <listitem><para>The symbolic name and version of the
+    package.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><replaceable>system</replaceable></term>
+  
+    <listitem><para>The platform identifier of the platform for which
+    this binary package is intended.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><replaceable>drvPath</replaceable></term>
+  
+    <listitem><para>The path in the Nix store of the derivation from
+    which <replaceable>outPath</replaceable> was built.  Not currently
+    used.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><replaceable>outPath</replaceable></term>
+  
+    <listitem><para>The path in the Nix store of the package.  After
+    <command>nix-install-package</command> has obtained the manifest
+    from <replaceable>manifestURL</replaceable>, it performs a
+    <literal>nix-env -i</literal> <replaceable>outPath</replaceable>
+    to install the binary package.</para></listitem>
+
+  </varlistentry>
+
+</variablelist>
+  
+</para>
+
+<para>An example follows:
+
+<screen>
+NIXPKG1 http://.../nixpkgs-0.10pre6622/MANIFEST subversion-1.4.0 i686-darwin \
+  /nix/store/4kh60jkp...-subversion-1.4.0.drv \
+  /nix/store/nkw7wpgb...-subversion-1.4.0</screen>
+
+(The line breaks (<literal>\</literal>) are for presentation purposes
+and not part of the actual file.)
+
+</para>
+
+</refsection>
+
+
+</refentry>
--- a/doc/manual/nix-instantiate.xml
+++ b/doc/manual/nix-instantiate.xml
@@ -1,65 +1,200 @@
-<refentry>
-  <refnamediv>
-    <refname>nix-instantiate</refname>
-    <refpurpose>instantiate store expressions from Nix expressions</refpurpose>
-  </refnamediv>
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+  
+<refmeta>
+  <refentrytitle>nix-instantiate</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>

-  <refsynopsisdiv>
-    <cmdsynopsis>
-      <command>nix-instantiate</command>
-      &opt-common-syn;
-      <arg choice='plain' rep='repeat'><replaceable>files</replaceable></arg>
-    </cmdsynopsis>
-  </refsynopsisdiv>
+<refnamediv>
+  <refname>nix-instantiate</refname>
+  <refpurpose>instantiate store derivations from Nix expressions</refpurpose>
+</refnamediv>

-  <refsection>
-    <title>Description</title>
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-instantiate</command>
+    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="opt-common-syn.xml#xmlns(db=http://docbook.org/ns/docbook)xpointer(/db:nop/*)" />
+    <arg><option>--arg</option> <replaceable>name</replaceable> <replaceable>value</replaceable></arg>
+    <arg>
+      <group choice='req'>
+        <arg choice='plain'><option>--attr</option></arg>
+        <arg choice='plain'><option>-A</option></arg>
+      </group>
+      <replaceable>attrPath</replaceable>
+    </arg>
+    <arg><option>--add-root</option> <replaceable>path</replaceable></arg>
+    <arg><option>--indirect</option></arg>
+    <arg>
+      <group choice='req'>
+        <arg choice='plain'><option>--parse-only</option></arg>
+        <arg choice='plain'>
+          <option>--eval-only</option>
+          <arg><option>--strict</option></arg>
+        </arg>
+      </group>
+      <arg><option>--xml</option></arg>
+    </arg>
+    <arg choice='plain' rep='repeat'><replaceable>files</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>

-    <para>
-      The command <command>nix-instantiate</command> generates
-      (low-level) store expressions from (high-level) Nix expressions.
-      It loads and evaluates the Nix expressions in each of
-      <replaceable>files</replaceable>.  Each top-level expression
-      should evaluate to a derivation, a list of derivations, or a set
-      of derivations.  The paths of the resulting store expressions
-      are printed on standard output.
-    </para>

-    <para>
-      This command is generally used for testing Nix expression before
-      they are used with <command>nix-env</command>.
-    </para>
+<refsection><title>Description</title>

-  </refsection>
+<para>The command <command>nix-instantiate</command> generates <link
+linkend="gloss-derivation">store derivations</link> from (high-level)
+Nix expressions.  It loads and evaluates the Nix expressions in each
+of <replaceable>files</replaceable>.  Each top-level expression should
+evaluate to a derivation, a list of derivations, or a set of
+derivations.  The paths of the resulting store derivations are printed
+on standard output.</para>

-  <refsection>
-    <title>Options</title>
+<para>If <replaceable>files</replaceable> is the character
+<literal>-</literal>, then a Nix expression will be read from standard
+input.</para>

-    <variablelist>
+<para>Most users and developers don’t need to use this command
+(<command>nix-env</command> and <command>nix-build</command> perform
+store derivation instantiation from Nix expressions automatically).
+It is most commonly used for implementing new deployment
+policies.</para>

-      &opt-common;
+<para>See also <xref linkend="sec-common-options" /> for a list of
+common options.</para>

-    </variablelist>
+</refsection>

-  </refsection>

-  <refsection>
-    <title>Examples</title>
+<refsection><title>Options</title>

-    <screen>
-$ nix-instantiate gcc.nix <lineannotation>(instantiate)</lineannotation>
-/nix/store/468abdcb93aa22bb721142615b97698b-d-gcc-3.3.2.store
+<variablelist>

-$ nix-store -r $(nix-instantiate gcc.nix) <lineannotation>(build)</lineannotation>
+  <varlistentry>
+    <term><option>--add-root</option> <replaceable>path</replaceable></term>
+    <term><option>--indirect</option></term>

-$ nix-store -r $(nix-instantiate gcc.nix) <lineannotation>(print output path)</lineannotation>
-/nix/store/9afa718cddfdfe94b5b9303d0430ceb1-gcc-3.3.2
+    <listitem><para>See the <link linkend="opt-add-root">corresponding
+    options</link> in <command>nix-store</command>.</para></listitem>

-$ ls -l /nix/store/9afa718cddfdfe94b5b9303d0430ceb1-gcc-3.3.2
-dr-xr-xr-x    2 eelco    users         360 2003-12-01 16:12 bin
-dr-xr-xr-x    3 eelco    users          72 2003-12-01 16:12 include
+  </varlistentry>
+
+    
+  <varlistentry><term><option>--parse-only</option></term>
+  
+    <listitem><para>Just parse the input files, and print their
+    abstract syntax trees on standard output in ATerm
+    format.</para></listitem>
+    
+  </varlistentry>
+      
+  <varlistentry><term><option>--eval-only</option></term>
+  
+    <listitem><para>Just parse and evaluate the input files, and print
+    the resulting values on standard output.  No instantiation of
+    store derivations takes place.</para></listitem>
+    
+  </varlistentry>
+
+  <varlistentry><term><option>--xml</option></term>
+
+    <listitem><para>When used with <option>--parse-only</option> and
+    <option>--eval-only</option>, print the resulting expression as an
+    XML representation of the abstract syntax tree rather than as an
+    ATerm.  The schema is the same as that used by the <link
+    linkend="builtin-toXML"><function>toXML</function>
+    built-in</link>.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><option>--strict</option></term>
+
+    <listitem><para>When used with <option>--eval-only</option>,
+    recursively evaluate list elements and attributes.  Normally, such
+    sub-expressions are left unevaluated (since the Nix expression
+    language is lazy).</para>
+
+    <warning><para>This option can cause non-termination, because lazy
+    data structures can be infinitely large.</para></warning>
+
+    </listitem>
+
+  </varlistentry>
+
+</variablelist>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<para>Instantiating store derivations from a Nix expression, and
+building them using <command>nix-store</command>:
+
+<screen>
+$ nix-instantiate test.nix <lineannotation>(instantiate)</lineannotation>
+/nix/store/cigxbmvy6dzix98dxxh9b6shg7ar5bvs-perl-BerkeleyDB-0.26.drv
+
+$ nix-store -r $(nix-instantiate test.nix) <lineannotation>(build)</lineannotation>
+<replaceable>...</replaceable>
+/nix/store/qhqk4n8ci095g3sdp93x7rgwyh9rdvgk-perl-BerkeleyDB-0.26 <lineannotation>(output path)</lineannotation>
+
+$ ls -l /nix/store/qhqk4n8ci095g3sdp93x7rgwyh9rdvgk-perl-BerkeleyDB-0.26
+dr-xr-xr-x    2 eelco    users        4096 1970-01-01 01:00 lib
 ...</screen>

-  </refsection>
-    
+</para>
+
+<para>Parsing and evaluating Nix expressions:
+
+<screen>
+$ echo '"foo" + "bar"' | nix-instantiate --parse-only -
+OpPlus(Str("foo"),Str("bar"))
+
+$ echo '"foo" + "bar"' | nix-instantiate --eval-only -
+Str("foobar")
+
+$ echo '"foo" + "bar"' | nix-instantiate --eval-only --xml -
+<![CDATA[<?xml version='1.0' encoding='utf-8'?>
+<expr>
+  <string value="foobar" />
+</expr>]]></screen>
+
+</para>
+
+<para>The difference between non-strict and strict evaluation:
+
+<screen>
+$ echo 'rec { x = "foo"; y = x; }' | nix-instantiate --eval-only --xml -
+<replaceable>...</replaceable><![CDATA[
+    <attr name="x">
+      <string value="foo" />
+    </attr>
+    <attr name="y">
+      <unevaluated />
+    </attr>]]>
+<replaceable>...</replaceable></screen>
+
+Note that <varname>y</varname> is left unevaluated (the XML
+representation doesn’t attempt to show non-normal forms).
+
+<screen>
+$ echo 'rec { x = "foo"; y = x; }' | nix-instantiate --eval-only --xml --strict -
+<replaceable>...</replaceable><![CDATA[
+    <attr name="x">
+      <string value="foo" />
+    </attr>
+    <attr name="y">
+      <string value="foo" />
+    </attr>]]>
+<replaceable>...</replaceable></screen>
+
+</para>
+
+</refsection>
+
+
 </refentry>
--- a/doc/manual/nix-lang-ref.xml
+++ b/doc/manual/nix-lang-ref.xml
@@ -1,4 +1,4 @@
-<chapter>
+<appendix>
  <title>Nix Language Reference</title>

  <sect1>
@@ -274,4 +274,4 @@
  </sect1>
  

-</chapter>
+</appendix>
--- a/doc/manual/nix-pack-closure.xml
+++ b/doc/manual/nix-pack-closure.xml
@@ -0,0 +1,82 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+
+<refmeta>
+  <refentrytitle>nix-pack-closure</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-pack-closure</refname>
+  <refpurpose>pack the closure of a store path into a single file that
+  can be unpacked with
+  <command>nix-unpack-closure</command></refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-pack-closure</command>
+    <arg choice='plain' rep='repeat'><replaceable>paths</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+
+<refsection><title>Description</title>
+
+<para>The command <command>nix-pack-closure</command> packs the
+contents of the store paths <replaceable>paths</replaceable> and
+<emphasis>all their dependencies</emphasis> into a single file, which
+is written to standard output.  (That is, it
+<emphasis>serialises</emphasis> <replaceable>paths</replaceable>.)
+The output can then be unpacked into the Nix store of another machine
+using <command>nix-unpack-closure</command>.</para>
+
+<para>Together, <command>nix-pack-closure</command> and
+<command>nix-unpack-closure</command> provide a quick and easy way to
+deploy a package to a different machine.  However, as the output of
+<command>nix-pack-closure</command> tends to be rather large (since it
+contains all dependencies), it’s not very efficient.
+<command>nix-push</command> and <command>nix-pull</command> are more
+efficient, but are also a bit more cumbersome to use.</para>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<para>To copy some instance of Subversion with all its dependencies to
+another machine:
+
+<screen>
+$ nix-pack-closure /nix/store/hj232g1r...-subversion-1.3.0 > svn.closure
+
+<lineannotation>Copy <!-- !!! <filename> -->svn.closure to the remote machine, then on the remote machine do:</lineannotation>
+$ nix-unpack-closure &lt; svn.closure</screen>
+
+</para>
+
+<para>Copy the program <command>azureus</command> with all its
+dependencies to the machine <literal>scratchy</literal>:
+
+<screen>
+$ nix-pack-closure $(which azureus) | ssh scratchy nix-unpack-closure</screen>
+    
+</para>
+
+<para>As a variation on the previous example, copy
+<command>azureus</command>, and also install it in the user’s profile
+on the target machine:
+
+<screen>
+$ nix-pack-closure $(which azureus) | ssh scratchy 'nix-env -i $(nix-unpack-closure)'</screen>
+
+</para>
+ 
+
+</refsection>
+
+
+</refentry>
--- a/doc/manual/nix-prefetch-url.xml
+++ b/doc/manual/nix-prefetch-url.xml
@@ -1,54 +1,78 @@
-<refentry>
-  <refnamediv>
-    <refname>nix-prefetch-url</refname>
-    <refpurpose>copy a file from a URL into the store and print its MD5 hash</refpurpose>
-  </refnamediv>
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+  
+<refmeta>
+  <refentrytitle>nix-prefetch-url</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>

-  <refsynopsisdiv>
-    <cmdsynopsis>
-      <command>nix-prefetch-url</command>
-      <arg choice='plain'><replaceable>url</replaceable></arg>
-    </cmdsynopsis>
-  </refsynopsisdiv>
+<refnamediv>
+  <refname>nix-prefetch-url</refname>
+  <refpurpose>copy a file from a URL into the store and print its MD5 hash</refpurpose>
+</refnamediv>

-  <refsection>
-    <title>Description</title>
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-prefetch-url</command>
+    <arg choice='plain'><replaceable>url</replaceable></arg>
+    <arg><replaceable>hash</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>

-    <para>
-      The command <command>nix-prefetch-url</command> downloads the
-      file referenced by the URL <replaceable>url</replaceable>,
-      prints its MD5 cryptographic hash code, and copies it into the
-      Nix store.  The file name in the store is
-      <filename><replaceable>hash</replaceable>-<replaceable>basename</replaceable></filename>,
-      where <replaceable>basename</replaceable> is everything
-      following the final slash in <replaceable>url</replaceable>.
-    </para>

-    <para>
-      This command is just a convenience to Nix expression writers.
-      Often a Nix expressions fetch some source distribution from the
-      network using the <literal>fetchurl</literal> expression
-      contained in <literal>nixpkgs</literal>.  However,
-      <literal>fetchurl</literal> requires an MD5 hash.  If you don't
-      know the hash, you would have to download the file first, and
-      then <literal>fetchurl</literal> would download it again when
-      you build your Nix expression.  Since
-      <literal>fetchurl</literal> uses the same name for the
-      downloaded file as <command>nix-prefetch-url</command>, the
-      redundant download can be avoided.
-    </para>
+<refsection><title>Description</title>

-  </refsection>
+<para>The command <command>nix-prefetch-url</command> downloads the
+file referenced by the URL <replaceable>url</replaceable>, prints its
+cryptographic hash, and copies it into the Nix store.  The file name
+in the store is
+<filename><replaceable>hash</replaceable>-<replaceable>baseName</replaceable></filename>,
+where <replaceable>baseName</replaceable> is everything following the
+final slash in <replaceable>url</replaceable>.</para>

-  <refsection>
-    <title>Examples</title>
+<para>This command is just a convenience for Nix expression writers.
+Often a Nix expression fetches some source distribution from the
+network using the <literal>fetchurl</literal> expression contained in
+Nixpkgs.  However, <literal>fetchurl</literal> requires a
+cryptographic hash.  If you don't know the hash, you would have to
+download the file first, and then <literal>fetchurl</literal> would
+download it again when you build your Nix expression.  Since
+<literal>fetchurl</literal> uses the same name for the downloaded file
+as <command>nix-prefetch-url</command>, the redundant download can be
+avoided.</para>

-    <screen>
+<para>The environment variable <envar>NIX_HASH_ALGO</envar> specifies
+which hash algorithm to use.  It can be either <literal>md5</literal>,
+<literal>sha1</literal>, or <literal>sha256</literal>.  The default is
+<literal>sha256</literal>.</para>
+
+<para>If <replaceable>hash</replaceable> is specified, then a download
+is not performed if the Nix store already contains a file with the
+same hash and base name.  Otherwise, the file is downloaded, and an
+error if signaled if the actual hash of the file does not match the
+specified hash.</para>
+
+<para>This command prints the hash on standard output.  Additionally,
+if the environment variable <envar>PRINT_PATH</envar> is set, the path
+of the downloaded file in the Nix store is also printed.</para>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<screen>
 $ nix-prefetch-url ftp://ftp.nluug.nl/pub/gnu/make/make-3.80.tar.bz2
-...
-file has hash 0bbd1df101bc0294d440471e50feca71
-...</screen>
+0bbd1df101bc0294d440471e50feca71
+
+$ PRINT_PATH=1 nix-prefetch-url ftp://ftp.nluug.nl/pub/gnu/make/make-3.80.tar.bz2
+0bbd1df101bc0294d440471e50feca71
+/nix/store/wvyz8ifdn7wyz1p3pqyn0ra45ka2l492-make-3.80.tar.bz2</screen>
+
+</refsection>

-  </refsection>
    
 </refentry>
--- a/doc/manual/nix-pull.xml
+++ b/doc/manual/nix-pull.xml
@@ -1,43 +1,49 @@
-<refentry>
-  <refnamediv>
-    <refname>nix-pull</refname>
-    <refpurpose>pull substitutes from a network cache</refpurpose>
-  </refnamediv>
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">

-  <refsynopsisdiv>
-    <cmdsynopsis>
-      <command>nix-pull</command>
-      <arg choice='plain'><replaceable>url</replaceable></arg>
-    </cmdsynopsis>
-  </refsynopsisdiv>
+<refmeta>
+  <refentrytitle>nix-pull</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>

-  <refsection>
-    <title>Description</title>
+<refnamediv>
+  <refname>nix-pull</refname>
+  <refpurpose>pull substitutes from a network cache</refpurpose>
+</refnamediv>

-    <para>
-      The command <command>nix-pull</command> obtains a list of
-      pre-built store paths from the URL
-      <replaceable>url</replaceable>, and for each of these store
-      paths, registers a substitute derivation that downloads and
-      unpacks it into the Nix store.  This is used to speed up
-      installations: if you attempt to install something that has
-      already been built and stored into the network cache, Nix can
-      transparently re-use the pre-built store paths.
-    </para>
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-pull</command>
+    <arg choice='plain'><replaceable>url</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>

-    <para>
-      The file at <replaceable>url</replaceable> must be compatible
-      with the files created by <replaceable>nix-push</replaceable>.
-    </para>

-  </refsection>
+<refsection><title>Description</title>

-  <refsection>
-    <title>Examples</title>
+<para>The command <command>nix-pull</command> obtains a list of
+pre-built store paths from the URL <replaceable>url</replaceable>, and
+for each of these store paths, registers a substitute derivation that
+downloads and unpacks it into the Nix store.  This is used to speed up
+installations: if you attempt to install something that has already
+been built and stored into the network cache, Nix can transparently
+re-use the pre-built store paths.</para>
+
+<para>The file at <replaceable>url</replaceable> must be compatible
+with the files created by <replaceable>nix-push</replaceable>.</para>
+
+</refsection>
+
+
+<refsection><title>Examples</title>
+
+<screen>
+$ nix-pull http://nix.cs.uu.nl/dist/nix/nixpkgs-0.5pre753/MANIFEST</screen>
+
+</refsection>

-    <screen>
-$ nix-pull http://catamaran.labs.cs.uu.nl/dist/nix/nixpkgs-0.5pre753/MANIFEST</screen>

-  </refsection>
-    
 </refentry>
--- a/doc/manual/nix-push.xml
+++ b/doc/manual/nix-push.xml
@@ -1,138 +1,128 @@
-<refentry>
-  <refnamediv>
-    <refname>nix-push</refname>
-    <refpurpose>push store paths onto a network cache</refpurpose>
-  </refnamediv>
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">

-  <refsynopsisdiv>
-    <cmdsynopsis>
-      <command>nix-push</command>
-      <arg choice='plain'><replaceable>archives-put-url</replaceable></arg>
-      <arg choice='plain'><replaceable>archives-get-url</replaceable></arg>
-      <arg choice='plain'><replaceable>manifest-put-url</replaceable></arg>
-      <arg choice='plain' rep='repeat'><replaceable>paths</replaceable></arg>
-    </cmdsynopsis>
-  </refsynopsisdiv>
+<refmeta>
+  <refentrytitle>nix-push</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>

-  <refsection>
-    <title>Description</title>
+<refnamediv>
+  <refname>nix-push</refname>
+  <refpurpose>push store paths onto a network cache</refpurpose>
+</refnamediv>

-    <para>
-      The command <command>nix-push</command> builds a set of store
-      expressions (if necessary), and then packages and uploads all
-      store paths in the resulting closures to a server.  A network
-      cache thus populated can subsequently be used to speed up
-      software deployment on other machines using the
-      <command>nix-pull</command> command.
-    </para>
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-push</command>
+    <group choice='req'>
+      <arg choice='req'>
+        <arg choice='plain'><replaceable>archivesPutURL</replaceable></arg>
+        <arg choice='plain'><replaceable>archivesGetURL</replaceable></arg>
+        <arg choice='plain'><replaceable>manifestPutURL</replaceable></arg>
+      </arg>
+      <arg choice='req'>
+        <arg choice='plain'><option>--copy</option></arg>
+        <arg choice='plain'><replaceable>archivesDir</replaceable></arg>
+        <arg choice='plain'><replaceable>manifestFile</replaceable></arg>
+      </arg>
+    </group>
+    <arg choice='plain' rep='repeat'><replaceable>paths</replaceable></arg>
+  </cmdsynopsis>
+</refsynopsisdiv>

-    <para>
-      <command>nix-push</command> performs the following actions.
+
+<refsection><title>Description</title>
+
+<para>The command <command>nix-push</command> builds a set of store
+paths (if necessary), and then packages and uploads all store paths in
+the resulting closures to a server.  A network cache thus populated
+can subsequently be used to speed up software deployment on other
+machines using the <command>nix-pull</command> command.</para>
+
+<para><command>nix-push</command> performs the following actions.
      
-      <orderedlist>
+<orderedlist>

-        <listitem>
-          <para>
-            The store expressions stored in
-            <replaceable>paths</replaceable> are realised (using
-            <literal>nix-store --realise</literal>).
-          </para>
-        </listitem>
+  <listitem><para>Each path in <replaceable>paths</replaceable> is
+  realised (using <link
+  linkend='rsec-nix-store-realise'><literal>nix-store
+  --realise</literal></link>).</para></listitem>

-        <listitem>
-          <para>
-            All paths in the closure of the store expressions stored
-            in <replaceable>paths</replaceable> are determined (using
-            <literal>nix-store --query --requisites
-            --include-successors</literal>).  It should be noted that
-            since the <option>--include-successors</option> flag is
-            used, if you specify a derivation store expression, you
-            get a combined source/binary distribution.  If you only
-            want a binary distribution, you should specify the closure
-            store expression that result from realising these (see
-            below).
-          </para>
-        </listitem>
+  <listitem><para>All paths in the closure of the store expressions
+  stored in <replaceable>paths</replaceable> are determined (using
+  <literal>nix-store --query --requisites
+  --include-outputs</literal>).  It should be noted that since the
+  <option>--include-outputs</option> flag is used, you get a combined
+  source/binary distribution.</para></listitem>

-        <listitem>
-          <para>
-            All store paths determined in the previous step are
-            packaged and compressed into a <command>bzip</command>ped
-            NAR archive (extension <filename>.nar.bz2</filename>).
-          </para>
-        </listitem>
+  <listitem><para>All store paths determined in the previous step are
+  packaged and compressed into a <command>bzip</command>ped NAR
+  archive (extension <filename>.nar.bz2</filename>).</para></listitem>

-        <listitem>
-          <para>
-            A <emphasis>manifest</emphasis> is created that contains
-            information on the store paths, their eventual URLs in the
-            cache, and cryptographic hashes of the contents of the NAR
-            archives.
-          </para>
-        </listitem>
+  <listitem><para>A <emphasis>manifest</emphasis> is created that
+  contains information on the store paths, their eventual URLs in the
+  cache, and cryptographic hashes of the contents of the NAR
+  archives.</para></listitem>

-        <listitem>
-          <para>
-            Each store path is uploaded to the remote directory
-            specified by <replaceable>archives-put-url</replaceable>.
-            HTTP PUT requests are used to do this.  However, before a
-            file <varname>x</varname> is uploaded to
-            <literal><replaceable>archives-put-url</replaceable>/<varname>x</varname></literal>,
-            <command>nix-push</command> first determines whether this
-            upload is unnecessary by issuing a HTTP HEAD request on
-            <literal><replaceable>archives-get-url</replaceable>/<varname>x</varname></literal>.
-            This allows a cache to be shared between many partially
-            overlapping <command>nix-push</command> invocations.
-            (We use two URLs because the upload URL typically
-            refers to a CGI script, while the download URL just refers
-            to a file system directory on the server.)
-          </para>
-        </listitem>
+  <listitem><para>Each store path is uploaded to the remote directory
+  specified by <replaceable>archivesPutURL</replaceable>.  HTTP PUT
+  requests are used to do this.  However, before a file
+  <varname>x</varname> is uploaded to
+  <literal><replaceable>archivesPutURL</replaceable>/</literal><varname>x</varname>,
+  <command>nix-push</command> first determines whether this upload is
+  unnecessary by issuing a HTTP HEAD request on
+  <literal><replaceable>archivesGetURL</replaceable>/</literal><varname>x</varname>.
+  This allows a cache to be shared between many partially overlapping
+  <command>nix-push</command> invocations.  (We use two URLs because
+  the upload URL typically refers to a CGI script, while the download
+  URL just refers to a file system directory on the
+  server.)</para></listitem>

-        <listitem>
-          <para>
-            The manifest is uploaded using an HTTP PUT request to
-            <replaceable>manifest-put-url</replaceable>.  The
-            corresponding URL to download the manifest can then be
-            used by <command>nix-pull</command>.
-          </para>
-        </listitem>
+  <listitem><para>The manifest is uploaded using an HTTP PUT request
+  to <replaceable>manifestPutURL</replaceable>.  The corresponding
+  URL to download the manifest can then be used by
+  <command>nix-pull</command>.</para></listitem>
        
-      </orderedlist>
-    </para>
+</orderedlist>
+
+</para>
+
+<!--
+<para>TODO:  <option>- -copy</option></para>
+-->
            
-  </refsection>
+</refsection>

-  <refsection>
-    <title>Examples</title>

-    <para>
-      To upload files there typically is some CGI script on the server
-      side.  This script should be be protected with a password.  The
-      following example uploads the store paths resulting from
-      building the Nix expressions in <filename>foo.nix</filename>,
-      passing appropriate authentication information:
+<refsection><title>Examples</title>
+
+<para>To upload files there typically is some CGI script on the server
+side.  This script should be be protected with a password.  The
+following example uploads the store paths resulting from building the
+Nix expressions in <filename>foo.nix</filename>, passing appropriate
+authentication information:
    
-      <screen>
+<screen>
 $ nix-push \
    http://foo@bar:server.domain/cgi-bin/upload.pl/cache \
    http://server.domain/cache \
    http://foo@bar:server.domain/cgi-bin/upload.pl/MANIFEST \
    $(nix-instantiate foo.nix)</screen>

-    This will push both sources and binaries (and any build-time
-    dependencies used in the build, such as compilers).
-    </para>
+This will push both sources and binaries (and any build-time
+dependencies used in the build, such as compilers).</para>

-    <para>
-      If we just want to push binaries, not sources and build-time
-      dependencies, we can do:
+<para>If we just want to push binaries, not sources and build-time
+dependencies, we can do:
      
-      <screen>
+<screen>
 $ nix-push <replaceable>urls</replaceable> $(nix-instantiate $(nix-store -r foo.nix))</screen>
    
-    </para>
+</para>

-  </refsection>
+</refsection>
    
 </refentry>
--- a/doc/manual/nix-store.xml
+++ b/doc/manual/nix-store.xml
--- a/doc/manual/nix-unpack-closure.xml
+++ b/doc/manual/nix-unpack-closure.xml
@@ -0,0 +1,42 @@
+<refentry xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+
+<refmeta>
+  <refentrytitle>nix-unpack-closure</refentrytitle>
+  <manvolnum>1</manvolnum>
+  <refmiscinfo class="source">Nix</refmiscinfo>
+  <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo>
+</refmeta>
+
+<refnamediv>
+  <refname>nix-unpack-closure</refname>
+  <refpurpose>unpack the closure of a store path created by <command>nix-pack-closure</command> into the Nix store</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+  <cmdsynopsis>
+    <command>nix-unpack-closure</command>
+  </cmdsynopsis>
+</refsynopsisdiv>
+
+
+<refsection><title>Description</title>
+
+<para>The command <command>nix-unpack-closure</command> unpacks the
+closure of a set of store paths created by
+<command>nix-pack-closure</command> into the local Nix store.  The
+closure is a single file read from standard input.  See the
+description of <command>nix-pack-closure</command> for details and
+examples.</para>
+
+<para>The top-level paths in the closure (i.e., the paths passed to
+the original <command>nix-pack-closure</command> call that created the
+closure) are printed on standard output.  These paths can be passed,
+for instance, to <literal>nix-env -i</literal> to install them into a
+user environment on the target machine.</para>
+
+</refsection>
+
+
+</refentry>
--- a/doc/manual/opt-common-syn.xml
+++ b/doc/manual/opt-common-syn.xml
@@ -1,9 +1,11 @@
+<nop xmlns="http://docbook.org/ns/docbook">
+  
 <arg><option>--help</option></arg>
 <arg><option>--version</option></arg>
 <arg rep='repeat'><option>--verbose</option></arg>
 <arg rep='repeat'><option>-v</option></arg>
-<arg><option>--build-output</option></arg>
-<arg><option>-B</option></arg>
+<arg><option>--no-build-output</option></arg>
+<arg><option>-Q</option></arg>
 <arg>
  <group choice='req'>
    <arg choice='plain'><option>--max-jobs</option></arg>
@@ -11,8 +13,17 @@
  </group>
  <replaceable>number</replaceable>
 </arg>
+<arg>
+  <arg><option>--max-silent-time</option></arg>
+  <replaceable>number</replaceable>
+</arg>
 <arg><option>--keep-going</option></arg>
 <arg><option>-k</option></arg>
 <arg><option>--keep-failed</option></arg>
 <arg><option>-K</option></arg>
 <arg><option>--fallback</option></arg>
+<arg><option>--readonly-mode</option></arg>
+<arg><option>--log-type</option> <replaceable>type</replaceable></arg>
+<sbr />
+
+</nop>
--- a/doc/manual/opt-common.xml
+++ b/doc/manual/opt-common.xml
@@ -1,174 +1,311 @@
-<varlistentry>
-  <term><option>--help</option></term>
+<section xmlns="http://docbook.org/ns/docbook" xml:id="sec-common-options">
+
+<title>Common options</title>
+
+
+<para>Most Nix commands accept the following command-line options:</para>
+
+<variablelist>
+
+<varlistentry><term><option>--help</option></term>
+  
+  <listitem><para>Prints out a summary of the command syntax and
+  exits.</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><option>--version</option></term>
+  
+  <listitem><para>Prints out the Nix version number on standard output
+  and exits.</para></listitem>
+</varlistentry>
+
+
+<varlistentry><term><option>--verbose</option></term>
+  <term><option>-v</option></term>
+
  <listitem>
-    <para>
-      Prints out a summary of the command syntax and exits.
+    
+  <para>Increases the level of verbosity of diagnostic messages
+  printed on standard error.  For each Nix operation, the information
+  printed on standard output is well-defined; any diagnostic
+  information is printed on standard error, never on standard
+  output.</para>
+
+  <para>This option may be specified repeatedly.  Currently, the
+  following verbosity levels exist:</para>
+
+  <variablelist>
+    
+    <varlistentry><term>0</term>
+    <listitem><para>“Errors only”: only print messages
+    explaining why the Nix invocation failed.</para></listitem>
+    </varlistentry>
+      
+    <varlistentry><term>1</term>
+    <listitem><para>“Informational”: print
+    <emphasis>useful</emphasis> messages about what Nix is doing.
+    This is the default.</para></listitem>
+    </varlistentry>
+      
+    <varlistentry><term>2</term>
+    <listitem><para>“Talkative”: print more informational
+    messages.</para></listitem>
+    </varlistentry>
+
+    <varlistentry><term>3</term>
+    <listitem><para>“Chatty”: print even more
+    informational messages.</para></listitem>
+    </varlistentry>
+
+    <varlistentry><term>4</term>
+    <listitem><para>“Debug”: print debug
+    information.</para></listitem>
+    </varlistentry>
+
+    <varlistentry><term>5</term>
+    <listitem><para>“Vomit”: print vast amounts of debug
+    information.</para></listitem>
+    </varlistentry>
+    
+  </variablelist>
+
+  </listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><option>--no-build-output</option></term>
+  <term><option>-Q</option></term>
+
+  <listitem><para>By default, output written by builders to standard
+  output and standard error is echoed to the Nix command's standard
+  error.  This option suppresses this behaviour.  Note that the
+  builder's standard output and error are always written to a log file
+  in
+  <filename><replaceable>prefix</replaceable>/nix/var/log/nix</filename>.</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry xml:id="opt-max-jobs"><term><option>--max-jobs</option></term>
+  <term><option>-j</option></term>
+
+  <listitem><para>Sets the maximum number of build jobs that Nix will
+  perform in parallel to the specified number.  The default is
+  specified by the <link
+  linkend='conf-build-max-jobs'><literal>build-max-jobs</literal></link>
+  configuration setting, which itself defaults to
+  <literal>1</literal>.  A higher value is useful on SMP systems or to
+  exploit I/O latency.  </para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry xml:id="opt-max-silent-time"><term><option>--max-silent-time</option></term>
+
+  <listitem><para>Sets the maximum number of seconds that a builder
+  can go without producing any data on standard output or standard
+  error.  The default is specified by the <link
+  linkend='conf-build-max-silent-time'><literal>build-max-silent-time</literal></link>
+  configuration setting.  <literal>0</literal> means no
+  time-out.</para></listitem>
+
+</varlistentry>
+
+<varlistentry><term><option>--keep-going</option></term>
+  <term><option>-k</option></term>
+
+  <listitem><para>Keep going in case of failed builds, to the
+  greatest extent possible.  That is, if building an input of some
+  derivation fails, Nix will still build the other inputs, but not the
+  derivation itself.  Without this option, Nix stops if any build
+  fails (except for builds of substitutes), possibly killing builds in
+  progress (in case of parallel or distributed builds).</para></listitem>
+  
+</varlistentry>
+
+
+<varlistentry><term><option>--keep-failed</option></term>
+  <term><option>-K</option></term>
+
+  <listitem><para>Specifies that in case of a build failure, the
+  temporary directory (usually in <filename>/tmp</filename>) in which
+  the build takes place should not be deleted.  The path of the build
+  directory is printed as an informational message.
    </para>
  </listitem>
 </varlistentry>


-<varlistentry>
-  <term><option>--version</option></term>
+<varlistentry><term><option>--fallback</option></term>
+
  <listitem>
-    <para>
-      Prints out the Nix version number on standard output and exits.
-    </para>
+
+  <para>Whenever Nix attempts to build a derivation for which
+  substitutes are known for each output path, but realising the output
+  paths through the substitutes fails, fall back on building the
+  derivation.</para>
+
+  <para>The most common scenario in which this is useful is when we
+  have registered substitutes in order to perform binary distribution
+  from, say, a network repository.  If the repository is down, the
+  realisation of the derivation will fail.  When this option is
+  specified, Nix will build the derivation instead.  Thus,
+  installation from binaries falls back on nstallation from source.
+  This option is not the default since it is generally not desirable
+  for a transient failure in obtaining the substitutes to lead to a
+  full build from source (with the related consumption of
+  resources).</para>
+
  </listitem>
+  
 </varlistentry>


-<varlistentry>
-  <term><option>--verbose</option> / <option>-v</option></term>
-  <listitem>
-    <para>
-      Increases the level of verbosity of diagnostic messages printed
-      on standard error.  For each Nix operation, the information
-      printed on standard output is well-defined; any diagnostic
-      information is printed on standard error, never on standard
-      output.
-    </para>
+<varlistentry><term><option>--readonly-mode</option></term>

-    <para>
-      This option may be specified repeatedly.  Currently, the
-      following verbosity levels exist:
-    </para>
-
-    <variablelist>
-      <varlistentry>
-        <term>0</term>
-        <listitem>
-          <para>
-            <quote>Errors only</quote>: only print messages explaining
-            why the Nix invocation failed.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term>1</term>
-        <listitem>
-          <para>
-            <quote>Informational</quote>: print
-            <emphasis>useful</emphasis> messages about what Nix is
-            doing.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term>2</term>
-        <listitem>
-          <para>
-            <quote>Talkative</quote>: print more informational messages.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term>3</term>
-        <listitem>
-          <para>
-            <quote>Chatty</quote>: print even more informational messages.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term>4</term>
-        <listitem>
-          <para>
-            <quote>Debug</quote>: print debug information:
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term>5</term>
-        <listitem>
-          <para>
-            <quote>Vomit</quote>: print vast amounts of debug
-            information.
-          </para>
-        </listitem>
-      </varlistentry>
-    </variablelist>
-
-  </listitem>
+  <listitem><para>When this option is used, no attempt is made to open
+  the Nix database.  Most Nix operations do need database access, so
+  those operations will fail.</para></listitem>
+  
 </varlistentry>


-<varlistentry>
-  <term><option>--build-output</option> / <option>-B</option></term>
+<varlistentry xml:id="opt-log-type"><term><option>--log-type</option>
+<replaceable>type</replaceable></term>
+
  <listitem>
-    <para>
-      Causes the output written by build actions to standard output
-      and standard error to be echoed to standard error, regardless of
-      verbosity level.  By default, it is only echoed at a verbosity
-      level of at least 4 (<quote>Debug</quote>), and is suppressed at
-      lower levels.  Note that it is always written to a log file in
-      <filename><replaceable>prefix</replaceable>/nix/var/log/nix</filename>.
-    </para>
+
+  <para>This option determines how the output written to standard
+  error is formatted.  Nix’s diagnostic messages are typically
+  <emphasis>nested</emphasis>.  For instance, when tracing Nix
+  expression evaluation (<command>nix-env -vvvvv</command>, messages
+  from subexpressions are nested inside their parent expressions.  Nix
+  builder output is also often nested.  For instance, the Nix Packages
+  generic builder nests the various build tasks (unpack, configure,
+  compile, etc.), and the GNU Make in <literal>stdenv-linux</literal>
+  has been patched to provide nesting for recursive Make
+  invocations.</para>
+
+  <para><replaceable>type</replaceable> can be one of the
+  following:
+
+  <variablelist>
+
+    <varlistentry><term><literal>pretty</literal></term>
+
+      <listitem><para>Pretty-print the output, indicating different
+      nesting levels using spaces.  This is the
+      default.</para></listitem>
+
+    </varlistentry>
+
+    <varlistentry><term><literal>escapes</literal></term>
+
+      <listitem><para>Indicate nesting using escape codes that can be
+      interpreted by the <command>nix-log2xml</command> tool in the
+      Nix source distribution.  The resulting XML file can be fed into
+      the <command>log2html.xsl</command> stylesheet to create an HTML
+      file that can be browsed interactively, using Javascript to
+      expand and collapse parts of the output.</para></listitem>
+
+    </varlistentry>
+
+    <varlistentry><term><literal>flat</literal></term>
+
+      <listitem><para>Remove all nesting.</para></listitem>
+
+    </varlistentry>
+
+  </variablelist>    
+  
+  </para>
+
  </listitem>
+  
 </varlistentry>


-<varlistentry>
-  <term><option>--max-jobs</option> / <option>-j</option></term>
-  <listitem>
-    <para>
-      Sets the maximum number of build jobs that Nix will perform in
-      parallel to the specified number.  The default is 1.  A higher
-      value is useful on SMP systems or to exploit I/O latency.
-    </para>
-  </listitem>
+<varlistentry><term><option>--arg</option> <replaceable>name</replaceable> <replaceable>value</replaceable></term>
+
+  <listitem><para>This option is accepted by
+  <command>nix-env</command>, <command>nix-instantiate</command> and
+  <command>nix-build</command>.  When evaluating Nix expressions, the
+  expression evaluator will automatically try to call functions that
+  it encounters.  It can automatically call functions for which every
+  argument has a <link linkend='ss-functions'>default value</link>
+  (e.g., <literal>{<replaceable>argName</replaceable> ?
+  <replaceable>defaultValue</replaceable>}:
+  <replaceable>...</replaceable></literal>).  With
+  <option>--arg</option>, you can also call functions that have
+  arguments without a default value (or override a default value).
+  That is, if the evaluator encounters a function with an argument
+  named <replaceable>name</replaceable>, it will call it with value
+  <replaceable>value</replaceable>.</para>
+
+  <para>For instance, the file
+  <literal>pkgs/top-level/all-packages.nix</literal> in Nixpkgs is
+  actually a function:
+
+<programlisting>
+{ # The system (e.g., `i686-linux') for which to build the packages.
+  system ? __currentSystem
+  <replaceable>...</replaceable>
+}: <replaceable>...</replaceable></programlisting>
+
+  So if you call this Nix expression (e.g., when you do
+  <literal>nix-env -i <replaceable>pkgname</replaceable></literal>),
+  the function will be called automatically using the value <link
+  linkend='builtin-currentSystem'><literal>__currentSystem</literal></link>
+  for the <literal>system</literal> argument.  You can override this
+  using <option>--arg</option>, e.g., <literal>nix-env -i
+  <replaceable>pkgname</replaceable> --arg system
+  \"i686-freebsd\"</literal>.  (Note that since the argument is a Nix
+  string literal, you have to escape the quotes.)</para></listitem>
+
 </varlistentry>


-<varlistentry>
-  <term><option>--keep-going</option> / <option>-k</option></term>
-  <listitem>
-    <para>
-      Keep going in case of failed builds, to the greatest extent
-      possible.  That is, if building an input of some derivation
-      fails, Nix will still build the other inputs, but not the
-      derivation itself.  Without this option, Nix stops if any build
-      fails (except for builds of substitutes), possibly killing
-      builds in progress (in case of parallel or distributed builds).
-    </para>
-  </listitem>
+<varlistentry><term><option>--argstr</option> <replaceable>name</replaceable> <replaceable>value</replaceable></term>
+
+  <listitem><para>This option is like <option>--arg</option>, only the
+  value is not a Nix expression but a string.  So instead of
+  <literal>--arg system \"i686-linux\"</literal> (the outer quotes are
+  to keep the shell happy) you can say <literal>--argstr system
+  i686-linux</literal>.</para></listitem>
+
 </varlistentry>


-<varlistentry>
-  <term><option>--keep-failed</option> / <option>-K</option></term>
-  <listitem>
-    <para>
-      Specifies that in case of a build failure, the temporary
-      directory (usually in <filename>/tmp</filename>) in which the
-      build takes place should not be deleted.  The path of the build
-      directory is printed as an informational message.
-    </para>
-  </listitem>
+<varlistentry xml:id="opt-attr"><term><option>--attr</option> / <option>-A</option>
+<replaceable>attrPath</replaceable></term>
+
+  <listitem><para>In <command>nix-env</command>,
+  <command>nix-instantiate</command> and <command>nix-build</command>,
+  <option>--attr</option> allows you to select an attribute from the
+  top-level Nix expression being evaluated.  The <emphasis>attribute
+  path</emphasis> <replaceable>attrPath</replaceable> is a sequence of
+  attribute names separated by dots.  For instance, given a top-level
+  Nix expression <replaceable>e</replaceable>, the attribute path
+  <literal>xorg.xorgserver</literal> would cause the expression
+  <literal><replaceable>e</replaceable>.xorg.xorgserver</literal> to
+  be used.  See <link
+  linkend='refsec-nix-env-install-examples'><command>nix-env
+  --install</command></link> for some concrete examples.</para>
+
+  <para>In addition to attribute names, you can also specify array
+  indices.  For instance, the attribute path
+  <literal>foo.3.bar</literal> selects the <literal>bar</literal>
+  attribute of the fourth element of the array in the
+  <literal>foo</literal> attribute of the top-level
+  expression.</para></listitem>
+
 </varlistentry>


-<varlistentry>
-  <term><option>--fallback</option></term>
-  <listitem>
-    <para>
-      Whenever Nix attempts to realise a derivation for which a
-      closure is already known, but this closure cannot be realised,
-      fall back on normalising the derivation.
-    </para>
+</variablelist>

-    <para>
-      The most common scenario in which this is useful is when we have
-      registered substitutes in order to perform binary distribution
-      from, say, a network repository.  If the repository is down, the
-      realisation of the derivation will fail.  When this option is
-      specified, Nix will build the derivation instead.  Thus,
-      binary installation falls back on a source installation.  This
-      option is not the default since it is generally not desirable
-      for a transient failure in obtaining the substitutes to lead to
-      a full build from source (with the related consumption of
-      resources).
-    </para>
-  </listitem>
-</varlistentry>

+</section>
--- a/doc/manual/opt-inst-syn.xml
+++ b/doc/manual/opt-inst-syn.xml
@@ -0,0 +1,22 @@
+<nop xmlns="http://docbook.org/ns/docbook">
+  
+  <arg>
+    <group choice='req'>
+      <arg choice='plain'><option>--prebuilt-only</option></arg>
+      <arg choice='plain'><option>-b</option></arg>
+    </group>
+  </arg>
+  
+  <arg>
+    <group choice='req'>
+      <arg choice='plain'><option>--attr</option></arg>
+      <arg choice='plain'><option>-A</option></arg>
+    </group>
+  </arg>
+
+  <arg><option>--from-expression</option></arg>
+  <arg><option>-E</option></arg>
+    
+  <arg><option>--from-profile</option> <replaceable>path</replaceable></arg>
+
+</nop>
--- a/doc/manual/overview.xml
+++ b/doc/manual/overview.xml
@@ -1,450 +0,0 @@
-<chapter id='chap-overview'>
-  <title>Overview</title>
-
-  <para>
-    This chapter provides a guided tour of Nix.
-  </para>
-
-
-  
-  <!--######################################################################-->
-
-  <sect1>
-    <title>Basic package management</title>
-
-    <para>
-      Let's start from the perspective of an end user.  Common operations at
-      this level are to install and remove packages, ask what packages are
-      installed or available for installation, and so on.  These are operations
-      on the <emphasis>user environment</emphasis>: the set of packages that a
-      user <quote>sees</quote>.  In a command line Unix environment, this means
-      the set of programs that are available through the <envar>PATH</envar>
-      environment variable.  (In other environments it might mean the set of
-      programs available on the desktop, through the start menu, and so on.)
-    </para>
-
-    <para>
-      The terms <quote>installation</quote> and <quote>uninstallation</quote>
-      are used in this context to denote the act of adding or removing packages
-      from the user environment.  In Nix, these operations are dissociated from
-      the physical copying or deleting of files.  Installation requires that
-      the files constituting the package are present, but they may be present
-      beforehand.  Likewise, uninstallation does not actually delete any files;
-      this is done automatically by running a garbage collector.
-    </para>
-
-    <para>
-      User environments are manipulated through the <command>nix-env</command>
-      command.  The query operation can be used to see what packages are
-      currently installed.
-    </para>
-
-    <screen>
-$ nix-env -q
-MozillaFirebird-0.7
-sylpheed-0.9.7
-pan-0.14.2</screen>
-
-    <para>
-      (<option>-q</option> is actually short for <option>--query
-        --installed</option>.)  The package names are symbolic: they don't have
-      any particular significance to Nix (as they shouldn't, since they are not
-      unique&mdash;there can be many derivations with the same name).  Note that
-      these packages have many dependencies (e.g., Mozilla uses the
-      <literal>gtk+</literal> package) but these have not been installed in the
-      user environment, though they are present on the system.  Generally,
-      there is no need to install such packages; only packages containing
-      programs should be installed.
-    </para>
-      
-    <para>
-      To install packages, a <emphasis>Nix expression</emphasis> is required
-      that tells Nix how to build that package.  There is a <ulink
-        url='https://svn.cs.uu.nl:12443/dist/trace/trace-nixpkgs-trunk.tar.bz2'>set 
-        of standard of Nix expressions</ulink> for many common packages.
-      Assuming that you have downloaded and unpacked these, you can view the
-      set of available packages:
-    </para>
-
-    <screen>
-$ nix-env -qaf pkgs/system/i686-linux.nix
-gettext-0.12.1
-sylpheed-0.9.7
-aterm-2.0
-gtk+-1.2.10
-apache-httpd-2.0.48
-pan-0.14.2
-...</screen>
-
-    <para>
-      The Nix expression in the file <filename>i686-linux.nix</filename> yields
-      the set of packages for a Linux system running on x86 hardware.  For
-      other platforms, copy and modify this file for your platform as
-      appropriate. [TODO: improve this]
-    </para>
-
-    <para>
-      It is also possible to see the <emphasis>status</emphasis> of available
-      packages, i.e., whether they are installed into the user environment
-      and/or present in the system:
-    </para>
-
-    <screen>
-$ nix-env -qasf pkgs/system/i686-linux.nix
-P gettext-0.12.1
-IP sylpheed-0.9.7
-- aterm-2.0
-P gtk+-1.2.10</screen>
-
-    <para>
-      This reveals that the <literal>sylpheed</literal> package is already
-      installed, or more precisely, that exactly the same instantiation of
-      <literal>sylpheed</literal> is installed.  This guarantees that the
-      available package is exactly the same as the installed package with
-      regard to sources, dependencies, build flags, and so on.  Similarly, we
-      see that the <literal>gettext</literal> and <literal>gtk+</literal>
-      packages are present but not installed in the user environment, while the
-      <literal>aterm</literal> package is not installed or present at all (so,
-      if we were to install it, it would have to be built or downloaded first).
-    </para>
-
-    <para>
-      The install operation is used install available packages from a Nix
-      environment.  To install the <literal>pan</literal> package (a
-      newsreader), you would do:
-    </para>
-
-    <screen>
-$ nix-env -if pkgs/system/i686-linux.nix pan</screen>
-
-    <para>
-      Since installation may take a long time, depending on whether any
-      packages need to be built or downloaded, it's a good idea to make
-      <command>nix-env</command> run verbosely by using the <option>-v</option>
-      (<option>--verbose</option>) option.  This option may be repeated to
-      increase the level of verbosity.  A good value is 3
-      (<option>-vvv</option>).
-    </para>
-
-    <para>
-      In fact, if you run this command verbosely you will observe that Nix
-      starts to build many packages, including large and fundamental ones such
-      as <literal>glibc</literal> and <literal>gcc</literal>.  I.e., you are
-      performing a source installation.  This is generally undesirable, since
-      installation from sources may require large amounts of disk and CPU
-      resources.  Therefore a <quote>binary</quote> installation is generally
-      preferable.
-    </para>
-
-    <para>
-      Rather than provide different mechanisms to create and perform
-      the installation of binary packages, Nix supports binary deployment
-      <emphasis>transparently</emphasis> through a generic mechanism of
-      <emphasis>substitute expressions</emphasis>.  If an request is made to
-      build some Nix expression, Nix will first try to build any substitutes
-      for that expression.  These substitutes presumably perform an identical
-      build operation with respect to the result, but require less resources.
-      For instance, a substitute that downloads a pre-built package from the
-      network requires less CPU and disk resources, and possibly less time.
-    </para>
-
-    <para>
-      Nix's use of cryptographic hashes makes this entirely safe.  It is not
-      possible, for instance, to accidentally substitute a build of some
-      package for a Solaris or Windows system for a build on a SuSE/x86 system.
-    </para>
-
-    <para>
-      While the substitute mechanism is a generic mechanism, Nix provides two
-      standard tools called <command>nix-pull</command> and
-      <command>nix-push</command> that maintain and use a shared cache of
-      prebuilt derivations on some network site (reachable through HTTP).  If
-      you attempt to install some package that someone else has previously
-      built and <quote>pushed</quote> into the cache, and you have done a
-      <quote>pull</quote> to register substitutes that download these prebuilt
-      packages, then the installation will automatically use these.
-    </para>
-
-    <para>
-      For example, to pull from our <ulink
-        url='http://losser.st-lab.cs.uu.nl/~eelco/nix-dist/'>cache</ulink> of
-      prebuilt packages (at the time of writing, for SuSE Linux/x86), use the
-      following command:
-    </para>
-
-    <screen>
-$ nix-pull http://catamaran.labs.cs.uu.nl/dist/nix/nixpkgs-<replaceable>version</replaceable>/MANIFEST
-obtaining list of Nix archives at http://catamaran.labs.cs.uu.nl/dist/nix/nixpkgs-<replaceable>version</replaceable>/MANIFEST...
-...</screen>
-
-    <para>
-      If <command>nix-pull</command> is run without any arguments, it will pull
-      from the URLs specified in the file
-      <filename><replaceable>prefix</replaceable>/etc/nix/prebuilts.conf</filename>.
-    </para>
-
-    <para>
-      Assuming that the <literal>pan</literal> installation produced no errors,
-      it can be used immediately, that is, it now appears in a directory in the
-      <envar>PATH</envar> environment variable.  Specifically,
-      <envar>PATH</envar> includes the entry
-      <filename><replaceable>prefix</replaceable>/var/nix/profiles/default/bin</filename>, 
-      where
-      <filename><replaceable>prefix</replaceable>/var/nix/profiles/default</filename> 
-      is just a symlink to the current user environment:
-    </para>
-
-    <screen>
-$ ls -l /nix/var/nix/profiles/
-...
-lrwxrwxrwx  1 eelco ... default-15-link -> /nix/store/1871...12b0-user-environment
-lrwxrwxrwx  1 eelco ... default-16-link -> /nix/store/59ba...df6b-user-environment
-lrwxrwxrwx  1 eelco ... default -> default-16-link</screen>
-
-    <para>
-      That is, <filename>default</filename> in this example is a link
-      to <filename>default-16-link</filename>, which is the current
-      user environment.  Before the installation, it pointed to
-      <filename>default-15-link</filename>.  Note that this means that
-      you can atomically roll-back to the previous user environment by
-      pointing the symlink <filename>default</filename> at
-      <filename>default-15-link</filename> again.  This also shows
-      that operations such as installation are atomic in the Nix
-      system: any arbitrarily complex set of installation,
-      uninstallation, or upgrade actions eventually boil down to the
-      single operation of pointing a symlink somewhere else (which can
-      be implemented atomically in Unix).
-    </para>
-
-    <para>
-      What's in a user environment? It's just a set of symlinks to the files
-      that constitute the installed packages.  For instance:
-    </para>
-
-    <screen>
-$ ls -l /nix/var/nix/profiles/default-16-link/bin
-lrwxrwxrwx  1 eelco ... MozillaFirebird -> /nix/store/35f8...4ae6-MozillaFirebird-0.7/bin/MozillaFirebird
-lrwxrwxrwx  1 eelco ... svn -> /nix/store/3829...fb5d-subversion-0.32.1/bin/svn
-...</screen>
-
-    <para>
-      Note that, e.g., <filename>svn</filename> =
-      <filename>/nix/var/nix/profiles/default/bin/svn</filename> =
-      <filename>/nix/var/nix/profiles/default-16-link/bin/svn</filename> =
-      <filename>/nix/store/59ba...df6b-user-environment/bin/svn</filename> =
-      <filename>/nix/store/3829...fb5d-subversion-0.32.1/bin/svn</filename>.
-    </para>
-
-    <para>
-      Naturally, packages can also be uninstalled:
-    </para>
-
-    <screen>
-$ nix-env -e pan</screen>
-
-    <para>
-      This means that the package is removed from the user
-      environment.  It is <emphasis>not</emphasis> yet removed from
-      the system.  When a package is uninstalled from a user
-      environment, it may still be used by other packages, or may
-      still be present in other user environments.  Deleting it under
-      such conditions would break those other packages or user
-      environments.  To prevent this, packages are only
-      <quote>physically</quote> deleted by running the Nix garbage
-      collector, which searches for all packages in the Nix store that
-      are no longer <quote>reachable</quote> from outside the store.
-      Thus, uninstalling a package is always safe: it cannot break
-      other packages.
-    </para>
-
-    <para>
-      Upgrading packages is easy.  Given a Nix expression that
-      contains newer versions of installed packages (that is, packages
-      with the same package name, but a higher version number),
-      <command>nix-env -u</command> will replace the installed package
-      in the user environment with the newer package.  For example,
-      
-      <screen>
-$ nix-env -uf pkgs/system/i686-linux.nix pan</screen>
-
-      looks for a newer version of Pan, and installs it if found.
-      Also useful is the ability to upgrade <emphasis>all</emphasis>
-      packages:
-      
-      <screen>
-$ nix-env -uf pkgs/system/i686-linux.nix '*'</screen>
-
-      The asterisk matches all installed packages<footnote><para>No,
-      we don't support arbitrary regular
-      expressions</para></footnote>.  Note that <literal>*</literal>
-      must be quoted to prevent shell globbing.
-    </para>
-
-  </sect1>
-
-
-  
-  <!--######################################################################-->
-
-  <sect1>
-    <title>Writing Nix expressions</title>
-
-    <sect2>
-      <title>A simple Nix expression</title>
-
-      <para>
-        This section shows how to write simple Nix expressions&mdash;the things
-        that describe how to build a package.
-      </para>
-
-      <example id='ex-hello-nix'>
-        <title>Nix expression for GNU Hello</title>
-        <programlisting>
-{stdenv, fetchurl, perl}: <co id='ex-hello-nix-co-1' />
-
-derivation { <co id='ex-hello-nix-co-2' />
-  name = "hello-2.1.1"; <co id='ex-hello-nix-co-3' />
-  system = stdenv.system; <co id='ex-hello-nix-co-4' />
-  builder = ./builder.sh; <co id='ex-hello-nix-co-5' />
-  src = fetchurl { <co id='ex-hello-nix-co-6' />
-    url = ftp://ftp.nluug.nl/pub/gnu/hello/hello-2.1.1.tar.gz;
-    md5 = "70c9ccf9fac07f762c24f2df2290784d";
-  };
-  stdenv = stdenv; <co id='ex-hello-nix-co-7' />
-  perl = perl;
-}</programlisting>
-      </example>
-
-      <para>
-        A simple Nix expression is shown in <xref linkend='ex-hello-nix' />. It
-        describes how to the build the <ulink
-          url='http://www.gnu.org/directory/GNU/hello.html'>GNU Hello
-          package</ulink>.  This package has several dependencies.  First, it
-        requires a number of other packages, such as a C compiler, standard
-        Unix shell tools, and Perl.  Rather than have this Nix expression refer
-        to and use specific versions of these packages, it should be generic;
-        that is, it should be a <emphasis>function</emphasis> that takes the
-        required packages as inputs and yield a build of the GNU Hello package
-        as a result.  This Nix expression defines a function with three
-        arguments <xref linkend='ex-hello-nix-co-1' />, namely:
-        <orderedlist>
-          <listitem><para><varname>stdenv</varname>, which should be a
-              <emphasis>standard environment package</emphasis>.  The standard
-              environment is a set of tools and other components that would be
-              expected in a fairly minimal Unix-like environment: a C compiler
-              and linker, Unix shell tools, and so on.</para>
-          </listitem>
-          <listitem><para><varname>fetchurl</varname>, which should be a
-              function that given parameters <varname>url</varname> and
-              <varname>md5</varname>, will fetch a file from the specified
-              location and check that this file has the given MD5 hash code.
-              The hash is required because build operations must be
-              <emphasis>pure</emphasis>: given the same inputs they should
-              always yield the same output.  Since network resources can change
-              at any time, we must in some way guarantee what the result will
-              be.</para>
-          </listitem>
-          <listitem><para><varname>perl</varname>, which should be a Perl
-              interpreter.</para>
-          </listitem>
-        </orderedlist>
-      </para>
-
-      <para>
-        The remainder of the file is the body of the function, which happens to
-        be a <emphasis>derivation</emphasis> <xref
-        linkend='ex-hello-nix-co-2' />, which is the built-in function
-        <varname>derivation</varname> applied to a set of attributes that
-        encode all the necessary information for building the GNU Hello
-        package. 
-      </para>
-
-      <example>
-        <title>Build script (<filename>builder.sh</filename>) for GNU
-          Hello</title>
-        <programlisting>
-#! /bin/sh
-
-buildinputs="$perl"
-. $stdenv/setup || exit 1
-
-tar xvfz $src || exit 1
-cd hello-* || exit 1
-./configure --prefix=$out || exit 1
-make || exit 1
-make install || exit 1</programlisting>
-      </example>
-
-    </sect2>
-
-    <sect2>
-      <title>A more complex Nix expression</title>
-
-      <example id='ex-svn-nix'>
-        <title>Nix expression for Subversion</title>
-        <programlisting>
-{ localServer ? false <co id='ex-svn-nix-co-1' />
-, httpServer ? false
-, sslSupport ? false
-, swigBindings ? false
-, stdenv, fetchurl
-, openssl ? null, httpd ? null, db4 ? null, expat, swig ? null
-}:
-
-assert !isNull expat; <co id='ex-svn-nix-co-2' />
-assert localServer -> !isNull db4;
-assert httpServer -> !isNull httpd &amp;&amp; httpd.expat == expat; <co id='ex-svn-nix-co-3' />
-assert sslSupport -> !isNull openssl &amp;&amp; (httpServer -> httpd.openssl == openssl);
-assert swigBindings -> !isNull swig;
-
-derivation {
-  name = "subversion-0.32.1";
-  system = stdenv.system;
-
-  builder = ./builder.sh;
-  src = fetchurl {
-    url = http://svn.collab.net/tarballs/subversion-0.32.1.tar.gz;
-    md5 = "b06717a8ef50db4b5c4d380af00bd901";
-  };
-
-  localServer = localServer;
-  httpServer = httpServer;
-  sslSupport = sslSupport;
-  swigBindings = swigBindings;
-
-  stdenv = stdenv;
-  openssl = if sslSupport then openssl else null; <co id='ex-svn-nix-co-4' />
-  httpd = if httpServer then httpd else null;
-  expat = expat;
-  db4 = if localServer then db4 else null;
-  swig = if swigBindings then swig else null;
-}</programlisting>
-      </example>
-
-      <para>
-        This example shows several features.  Default parameters <xref
-          linkend='ex-svn-nix-co-1'/> can be used to simplify call sites: if an
-        argument that has a default is omitted, its default value is used.
-      </para>
-
-      <para>
-        You can use <emphasis>assertions</emphasis> to test whether arguments
-        satisfy certain constraints.  The simple assertion <xref
-          linkend='ex-svn-nix-co-2'/> tests whether the
-        <varname>expat</varname> argument is not a null value.  The more
-        complex assertion <xref linkend='ex-svn-nix-co-3'/> says that if
-        Subversion is built with Apache support, then <varname>httpd</varname>
-        (the Apache package) must not be null and it must have been built using
-        the same instance of the <varname>expat</varname> library as was passed
-        to the Subversion expression.  This is since the Subversion code is
-        dynamically linked against the Apache code and they both use Expat,
-        they must be linked against the same instance&mdash;otherwise a
-        conflict might occur. 
-      </para>
-
-    </sect2>
-
-  </sect1>
-
-
-</chapter>
--- a/doc/manual/package-management.xml
+++ b/doc/manual/package-management.xml
@@ -0,0 +1,532 @@
+<chapter xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id='chap-package-management'>
+
+<title>Package Management</title>
+
+
+<para>This chapter discusses how to do package management with Nix,
+i.e., how to obtain, install, upgrade, and erase packages.  This is
+the “user’s” perspective of the Nix system — people
+who want to <emphasis>create</emphasis> packages should consult
+<xref linkend='chap-writing-nix-expressions' />.</para>
+
+
+<section><title>Basic package management</title>
+
+<para>The main command for package management is <link
+linkend="sec-nix-env"><command>nix-env</command></link>.  You can use
+it to install, upgrade, and erase packages, and to query what
+packages are installed or are available for installation.</para>
+
+<para>In Nix, different users can have different “views”
+on the set of installed applications.  That is, there might be lots of
+applications present on the system (possibly in many different
+versions), but users can have a specific selection of those active —
+where “active” just means that it appears in a directory
+in the user’s <envar>PATH</envar>.  Such a view on the set of
+installed applications is called a <emphasis>user
+environment</emphasis>, which is just a directory tree consisting of
+symlinks to the files of the active applications.  </para>
+
+<para>Components are installed from a set of <emphasis>Nix
+expressions</emphasis> that tell Nix how to build those packages,
+including, if necessary, their dependencies.  There is a collection of
+Nix expressions called the Nix Package collection that contains
+packages ranging from basic development stuff such as GCC and Glibc,
+to end-user applications like Mozilla Firefox.  (Nix is however not
+tied to the Nix Package collection; you could write your own Nix
+expressions based on it, or completely new ones.)  You can download
+the latest version from <link
+xlink:href='http://nix.cs.uu.nl/dist/nix' />.</para>
+
+<para>Assuming that you have downloaded and unpacked a release of Nix
+Packages, you can view the set of available packages in the release:
+
+<screen>
+$ nix-env -qaf nixpkgs-<replaceable>version</replaceable> '*'
+ant-blackdown-1.4.2
+aterm-2.2
+bash-3.0
+binutils-2.15
+bison-1.875d
+blackdown-1.4.2
+bzip2-1.0.2
+...</screen>
+
+where <literal>nixpkgs-<replaceable>version</replaceable></literal> is
+where you’ve unpacked the release.  The flag <option>-q</option>
+specifies a query operation; <option>-a</option> means that you want
+to show the “available” (i.e., installable) packages, as opposed to
+the installed packages; and <option>-f</option>
+<filename>nixpkgs-<replaceable>version</replaceable></filename>
+specifies the source of the packages.  The argument
+<literal>'*'</literal> shows all installable packages. (The quotes are
+necessary to prevent shell expansion.)  You can also select specific
+packages by name:
+
+<screen>
+$ nix-env -qaf nixpkgs-<replaceable>version</replaceable> gcc
+gcc-3.4.6
+gcc-4.0.3
+gcc-4.1.1</screen>
+
+</para>
+
+<para>It is also possible to see the <emphasis>status</emphasis> of
+available packages, i.e., whether they are installed into the user
+environment and/or present in the system:
+
+<screen>
+$ nix-env -qasf nixpkgs-<replaceable>version</replaceable> '*'
+...
+-PS bash-3.0
+--S binutils-2.15
+IPS bison-1.875d
+...</screen>
+
+The first character (<literal>I</literal>) indicates whether the
+package is installed in your current user environment.  The second
+(<literal>P</literal>) indicates whether it is present on your system
+(in which case installing it into your user environment would be a
+very quick operation).  The last one (<literal>S</literal>) indicates
+whether there is a so-called <emphasis>substitute</emphasis> for the
+package, which is Nix’s mechanism for doing binary deployment.  It
+just means that Nix knows that it can fetch a pre-built package from
+somewhere (typically a network server) instead of building it
+locally.</para>
+
+<para>So now that we have a set of Nix expressions we can build the
+packages contained in them.  This is done using <literal>nix-env
+-i</literal>.  For instance,
+
+<screen>
+$ nix-env -f nixpkgs-<replaceable>version</replaceable> -i subversion</screen>
+
+will install the package called <literal>subversion</literal> (which
+is, of course, the <link
+xlink:href='http://subversion.tigris.org/'>Subversion version
+management system</link>).</para>
+
+<para>When you do this for the first time, Nix will start building
+Subversion and all its dependencies.  This will take quite a while —
+typically an hour or two on modern machines.  Fortunately, there is a
+faster way (so do a Ctrl-C on that install operation!): you just need
+to tell Nix that pre-built binaries of all those packages are
+available somewhere.  This is done using the
+<command>nix-pull</command> command, which must be supplied with a URL
+containing a <emphasis>manifest</emphasis> describing what binaries
+are available.  This URL should correspond to the Nix Packages release
+that you’re using.  For instance, if you obtained a release from <link
+xlink:href='http://nix.cs.uu.nl/dist/nix/nixpkgs-0.6pre1554/' />, then
+you should do:
+
+<screen>
+$ nix-pull http://nix.cs.uu.nl/dist/nix/nixpkgs-0.6pre1554/MANIFEST</screen>
+
+If you then issue the installation command, it should start
+downloading binaries from <systemitem
+class='fqdomainname'>nix.cs.uu.nl</systemitem>, instead of building
+them from source.  This might still take a while since all
+dependencies must be downloaded, but on a reasonably fast connection
+such as an DSL line it’s on the order of a few minutes.</para>
+
+<para>Naturally, packages can also be uninstalled:
+
+<screen>
+$ nix-env -e subversion</screen>
+
+</para>
+
+<para>Upgrading to a new version is just as easy.  If you have a new
+release of Nix Packages, you can do:
+
+<screen>
+$ nix-env -f nixpkgs-<replaceable>version</replaceable> -u subversion</screen>
+
+This will <emphasis>only</emphasis> upgrade Subversion if there is a
+“newer” version in the new set of Nix expressions, as
+defined by some pretty arbitrary rules regarding ordering of version
+numbers (which generally do what you’d expect of them).  To just
+unconditionally replace Subversion with whatever version is in the Nix
+expressions, use <parameter>-i</parameter> instead of
+<parameter>-u</parameter>; <parameter>-i</parameter> will remove
+whatever version is already installed.</para>
+
+<para>You can also upgrade all packages for which there are newer
+versions:
+
+<screen>
+$ nix-env -f nixpkgs-<replaceable>version</replaceable> -u '*'</screen>
+
+</para>
+
+<para>Sometimes it’s useful to be able to ask what
+<command>nix-env</command> would do, without actually doing it.  For
+instance, to find out what packages would be upgraded by
+<literal>nix-env -u '*'</literal>, you can do
+
+<screen>
+$ nix-env ... -u '*' --dry-run
+(dry run; not doing anything)
+upgrading `libxslt-1.1.0' to `libxslt-1.1.10'
+upgrading `graphviz-1.10' to `graphviz-1.12'
+upgrading `coreutils-5.0' to `coreutils-5.2.1'</screen>
+
+</para>
+
+<para>If you grow bored of specifying the Nix expressions using
+<parameter>-f</parameter> all the time, you can set a default
+location:
+
+<screen>
+$ nix-env -I nixpkgs-<replaceable>version</replaceable></screen>
+
+After this you can just say, for instance, <literal>nix-env -u
+'*'</literal>.<footnote><para>Setting a default using
+<parameter>-I</parameter> currently clashes with using Nix channels,
+since <literal>nix-channel --update</literal> calls <literal>nix-env
+-I</literal> to set the default to the Nix expressions it downloaded
+from the channel, replacing whatever default you had
+set.</para></footnote></para>
+
+</section>
+
+
+<section xml:id="sec-profiles"><title>Profiles</title>
+
+<para>Profiles and user environments are Nix’s mechanism for
+implementing the ability to allow different users to have different
+configurations, and to do atomic upgrades and rollbacks.  To
+understand how they work, it’s useful to know a bit about how Nix
+works.  In Nix, packages are stored in unique locations in the
+<emphasis>Nix store</emphasis> (typically,
+<filename>/nix/store</filename>).  For instance, a particular version
+of the Subversion package might be stored in a directory
+<filename>/nix/store/dpmvp969yhdqs7lm2r1a3gng7pyq6vy4-subversion-1.1.3/</filename>,
+while another version might be stored in
+<filename>/nix/store/5mq2jcn36ldlmh93yj1n8s9c95pj7c5s-subversion-1.1.2</filename>.
+The long strings prefixed to the directory names are cryptographic
+hashes<footnote><para>160-bit truncations of SHA-256 hashes encoded in
+a base-32 notation, to be precise.</para></footnote> of
+<emphasis>all</emphasis> inputs involved in building the package —
+sources, dependencies, compiler flags, and so on.  So if two
+packages differ in any way, they end up in different locations in
+the file system, so they don’t interfere with each other.  <xref
+linkend='fig-user-environments' /> shows a part of a typical Nix
+store.</para>
+
+<figure xml:id='fig-user-environments'><title>User environments</title>
+  <mediaobject>
+    <imageobject>
+      <imagedata fileref='figures/user-environments.png' format='PNG' />
+    </imageobject>
+  </mediaobject>
+</figure>
+
+<para>Of course, you wouldn’t want to type
+
+<screen>
+$ /nix/store/dpmvp969yhdq...-subversion-1.1.3/bin/svn</screen>
+
+every time you want to run Subversion.  Of course we could set up the
+<envar>PATH</envar> environment variable to include the
+<filename>bin</filename> directory of every package we want to use,
+but this is not very convenient since changing <envar>PATH</envar>
+doesn’t take effect for already existing processes.  The solution Nix
+uses is to create directory trees of symlinks to
+<emphasis>activated</emphasis> packages.  These are called
+<emphasis>user environments</emphasis> and they are packages
+themselves (though automatically generated by
+<command>nix-env</command>), so they too reside in the Nix store.  For
+instance, in <xref linkend='fig-user-environments' /> the user
+environment <filename>/nix/store/5mq2jcn36ldl...-user-env</filename>
+contains a symlink to just Subversion 1.1.2 (arrows in the figure
+indicate symlinks).  This would be what we would obtain if we had done
+
+<screen>
+$ nix-env -i subversion</screen>
+
+on a set of Nix expressions that contained Subversion 1.1.2.</para>
+
+<para>This doesn’t in itself solve the problem, of course; you
+wouldn’t want to type
+<filename>/nix/store/0c1p5z4kda11...-user-env/bin/svn</filename>
+either.  That’s why there are symlinks outside of the store that point
+to the user environments in the store; for instance, the symlinks
+<filename>default-42-link</filename> and
+<filename>default-43-link</filename> in the example.  These are called
+<emphasis>generations</emphasis> since every time you perform a
+<command>nix-env</command> operation, a new user environment is
+generated based on the current one.  For instance, generation 43 was
+created from generation 42 when we did
+
+<screen>
+$ nix-env -i subversion mozilla</screen>
+
+on a set of Nix expressions that contained Mozilla and a new version
+of Subversion.</para>
+
+<para>Generations are grouped together into
+<emphasis>profiles</emphasis> so that different users don’t interfere
+with each other if they don’t want to.  For example:
+
+<screen>
+$ ls -l /nix/var/nix/profiles/
+...
+lrwxrwxrwx  1 eelco ... default-42-link -> /nix/store/0c1p5z4kda11...-user-env
+lrwxrwxrwx  1 eelco ... default-43-link -> /nix/store/3aw2pdyx2jfc...-user-env
+lrwxrwxrwx  1 eelco ... default -> default-43-link</screen>
+
+This shows a profile called <filename>default</filename>.  The file
+<filename>default</filename> itself is actually a symlink that points
+to the current generation.  When we do a <command>nix-env</command>
+operation, a new user environment and generation link are created
+based on the current one, and finally the <filename>default</filename>
+symlink is made to point at the new generation.  This last step is
+atomic on Unix, which explains how we can do atomic upgrades.  (Note
+that the building/installing of new packages doesn’t interfere in
+any way with old packages, since they are stored in different
+locations in the Nix store.)</para>
+
+<para>If you find that you want to undo a <command>nix-env</command>
+operation, you can just do
+
+<screen>
+$ nix-env --rollback</screen>
+
+which will just make the current generation link point at the previous
+link.  E.g., <filename>default</filename> would be made to point at
+<filename>default-42-link</filename>.  You can also switch to a
+specific generation:
+
+<screen>
+$ nix-env --switch-generation 43</screen>
+
+which in this example would roll forward to generation 43 again.  You
+can also see all available generations:
+
+<screen>
+$ nix-env --list-generations</screen></para>
+
+<para>Actually, there is another level of indirection not shown in the
+figure above.  You generally wouldn’t have
+<filename>/nix/var/nix/profiles/<replaceable>some-profile</replaceable>/bin</filename>
+in your <envar>PATH</envar>.  Rather, there is a symlink
+<filename>~/.nix-profile</filename> that points to your current
+profile.  This means that you should put
+<filename>~/.nix-profile/bin</filename> in your <envar>PATH</envar>
+(and indeed, that’s what the initialisation script
+<filename>/nix/etc/profile.d/nix.sh</filename> does).  This makes it
+easier to switch to a different profile.  You can do that using the
+command <command>nix-env --switch-profile</command>:
+
+<screen>
+$ nix-env --switch-profile /nix/var/nix/profiles/my-profile
+
+$ nix-env --switch-profile /nix/var/nix/profiles/default</screen>
+
+These commands switch to the <filename>my-profile</filename> and
+default profile, respectively.  If the profile doesn’t exist, it will
+be created automatically.  You should be careful about storing a
+profile in another location than the <filename>profiles</filename>
+directory, since otherwise it might not be used as a root of the
+garbage collector (see section <xref linkend='sec-garbage-collection'
+/>).</para>
+
+<para>All <command>nix-env</command> operations work on the profile
+pointed to by <command>~/.nix-profile</command>, but you can override
+this using the <option>--profile</option> option (abbreviation
+<option>-p</option>):
+
+<screen>
+$ nix-env -p /nix/var/nix/profiles/other-profile -i subversion</screen>
+
+This will <emphasis>not</emphasis> change the
+<command>~/.nix-profile</command> symlink.</para>
+
+</section>
+
+
+<section xml:id='sec-garbage-collection'><title>Garbage collection</title>
+
+<para><command>nix-env</command> operations such as upgrades
+(<option>-u</option>) and uninstall (<option>-e</option>) never
+actually delete packages from the system.  All they do (as shown
+above) is to create a new user environment that no longer contains
+symlinks to the “deleted” packages.</para>
+
+<para>Of course, since disk space is not infinite, unused packages
+should be removed at some point.  You can do this by running the Nix
+garbage collector.  It will remove from the Nix store any package
+not used (directly or indirectly) by any generation of any
+profile.</para>
+
+<para>Note however that as long as old generations reference a
+package, it will not be deleted.  After all, we wouldn’t be able to
+do a rollback otherwise.  So in order for garbage collection to be
+effective, you should also delete (some) old generations.  Of course,
+this should only be done if you are certain that you will not need to
+roll back.</para>
+
+<para>To delete all old (non-current) generations of your current
+profile:
+
+<screen>
+$ nix-env --delete-generations old</screen>
+
+Instead of <literal>old</literal> you can also specify a list of
+generations, e.g.,
+
+<screen>
+$ nix-env --delete-generations 10 11 14</screen>
+
+</para>
+
+<para>After removing appropriate old generations you can run the
+garbage collector as follows:
+
+<screen>
+$ nix-store --gc</screen>
+
+If you are feeling uncertain, you can also first view what files would
+be deleted:
+
+<screen>
+$ nix-store --gc --print-dead</screen>
+
+Likewise, the option <option>--print-live</option> will show the paths
+that <emphasis>won’t</emphasis> be deleted.</para>
+
+<para>There is also a convenient little utility
+<command>nix-collect-garbage</command>, which when invoked with the
+<option>-d</option> (<option>--delete-old</option>) switch deletes all
+old generations of all profiles in
+<filename>/nix/var/nix/profiles</filename>.  So
+
+<screen>
+$ nix-collect-garbage -d</screen>
+
+is a quick and easy way to clean up your system.</para>
+
+
+
+
+<section xml:id="ssec-gc-roots"><title>Garbage collector roots</title>
+
+<para>The roots of the garbage collector are all store paths to which
+there are symlinks in the directory
+<filename><replaceable>prefix</replaceable>/nix/var/nix/gcroots</filename>.
+For instance, the following command makes the path
+<filename>/nix/store/d718ef...-foo</filename> a root of the collector:
+
+<screen>
+$ ln -s /nix/store/d718ef...-foo /nix/var/nix/gcroots/bar</screen>
+	
+That is, after this command, the garbage collector will not remove
+<filename>/nix/store/d718ef...-foo</filename> or any of its
+dependencies.</para>
+
+<para>Subdirectories of
+<filename><replaceable>prefix</replaceable>/nix/var/nix/gcroots</filename>
+are also searched for symlinks.  Symlinks to non-store paths are
+followed and searched for roots, but symlinks to non-store paths
+<emphasis>inside</emphasis> the paths reached in that way are not
+followed to prevent infinite recursion.</para>
+
+</section>
+
+</section>
+
+
+<section xml:id="sec-channels"><title>Channels</title>
+
+<para>If you want to stay up to date with a set of packages, it’s not
+very convenient to manually download the latest set of Nix expressions
+for those packages, use <command>nix-pull</command> to register
+pre-built binaries (if available), and upgrade using
+<command>nix-env</command>.  Fortunately, there’s a better way:
+<emphasis>Nix channels</emphasis>.</para>
+
+<para>A Nix channel is just a URL that points to a place that contains
+a set of Nix expressions and a manifest.  Using the command <link
+linkend="sec-nix-channel"><command>nix-channel</command></link> you
+can automatically stay up to date with whatever is available at that
+URL.</para>
+
+<para>You can “subscribe” to a channel using
+<command>nix-channel --add</command>, e.g.,
+
+<screen>
+$ nix-channel --add http://nix.cs.uu.nl/dist/nix/channels-v3/nixpkgs-unstable</screen>
+
+subscribes you to a channel that always contains that latest version
+of the Nix Packages collection.  (Instead of
+<literal>nixpkgs-unstable</literal> you could also subscribe to
+<literal>nixpkgs-stable</literal>, which should have a higher level of
+stability, but right now is just outdated.)  Subscribing really just
+means that the URL is added to the file
+<filename>~/.nix-channels</filename>.  Right now there is no command
+to “unsubscribe”; you should just edit that file manually
+and delete the offending URL.</para>
+
+<para>To obtain the latest Nix expressions available in a channel, do
+
+<screen>
+$ nix-channel --update</screen>
+
+This downloads the Nix expressions in every channel (downloaded from
+<literal><replaceable>url</replaceable>/nixexprs.tar.bz2</literal>)
+and registers any available pre-built binaries in every channel
+(by <command>nix-pull</command>ing
+<literal><replaceable>url</replaceable>/MANIFEST</literal>).  It also
+makes the union of each channel’s Nix expressions the default for
+<command>nix-env</command> operations.  Consequently, you can then say
+
+<screen>
+$ nix-env -u '*'</screen>
+
+to upgrade all packages in your profile to the latest versions
+available in the subscribed channels.</para>
+
+</section>
+
+
+<section xml:id="sec-one-click"><title>One-click installs</title>
+
+<para>Often, when you want to install a specific package (e.g., from
+the <link
+xlink:href="http://nix.cs.uu.nl/dist/nix/nixpkgs-unstable-latest/">Nix
+Packages collection</link> or from our <link
+xlink:href='http://nix.cs.uu.nl/dist/'>release server</link>),
+subscribing to a channel is a bit cumbersome.  And channels don’t help
+you at all if you want to install an older version of a package than
+the one provided by the current contents of the channel, or a package
+that has been removed from the channel.  That’s when
+<emphasis>one-click installs</emphasis> come in handy: you can just go
+to the web page that contains the package, click on it, and it will be
+installed with all the necessary dependencies.</para>
+
+<para>For instance, you can go to <link
+xlink:href="http://nix.cs.uu.nl/dist/nix/nixpkgs-unstable-latest/" />
+— or to any older release of Nix Packages — and click on any link for
+the individual packages for your platform (say, <link
+xlink:href='http://nix.cs.uu.nl/dist/nix/nixpkgs-0.10pre6622/pkgs/subversion-1.4.0-i686-linux.nixpkg'><literal>subversion-1.4.0</literal>
+for <literal>i686-linux</literal></link>).  The first time you do
+this, your browser will ask what to do with
+<literal>application/nix-package</literal> files.  You should open
+them with <filename>/nix/bin/nix-install-package</filename>.  This
+will open a window that asks you to confirm that you want to install
+the package.  When you answer <literal>Y</literal>, the package and
+all its dependencies will be installed.  This is a binary deployment
+mechanism — you get packages pre-compiled for the selected platform
+type.</para>
+
+<para>You can also install <literal>application/nix-package</literal>
+files from the command line directly.  See <xref
+linkend='sec-nix-install-package' /> for details.</para>
+
+</section>
+
+
+</chapter>
--- a/doc/manual/quick-start.xml
+++ b/doc/manual/quick-start.xml
@@ -1,141 +1,136 @@
-<chapter>
-  <title>Quick Start</title>
+<chapter xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink">

-  <para>
-    This chapter is for impatient people who don't like reading
-    documentation.  For more in-depth information you are kindly
-    referred to <xref linkend='chap-installation' /> and <xref
-    linkend='chap-overview' />.
-  </para>
+<title>Quick Start</title>

-  <orderedlist>

-    <listitem>
-      <para>
-        Download a source tarball or RPM from <ulink
-        url='http://www.cs.uu.nl/groups/ST/Trace/Nix'/>.
-        Build source distributions using the regular sequence:
+<para>This chapter is for impatient people who don't like reading
+documentation.  For more in-depth information you are kindly referred
+to the following chapters.</para>
+
+<orderedlist>
+
+<listitem><para>Download a source tarball or RPM from <link
+xlink:href='http://nix.cs.uu.nl/'/>.  Build source
+distributions using the regular sequence:
        
-        <screen>
+<screen>
 $ tar xvfj nix-<replaceable>version</replaceable>.tar.bz2
 $ ./configure
 $ make
 $ make install <lineannotation>(as root)</lineannotation></screen>

-        This will install Nix in <filename>/nix</filename>.  You
-        should also add <filename>/nix/etc/profile.d/nix.sh</filename>
-        to your <filename>~/.bashrc</filename> (or some other login
-        file).
-      </para>
-    </listitem>
+This will install Nix in <filename>/nix</filename>.  You shouldn't
+change the prefix if at all possible since that will make it
+impossible to use pre-built binaries from the Nixpkgs channel and
+other channels.  Alternatively, you could grab an RPM if you're on an
+RPM-based system.  You should also add
+<filename>/nix/etc/profile.d/nix.sh</filename> to your
+<filename>~/.bashrc</filename> (or some other login
+file).</para></listitem>

-    <listitem>
-      <para>
-        Get some Nix expressions for pre-built packages by downloading
-        the latest <literal>nixpkgs</literal> distribution (from the
-        same location), and unpack them.
+<listitem><para>Subscribe to the Nix Packages channel.

-        <screen>
-$ wget http://<replaceable>...</replaceable>/nix/nixpkgs-<replaceable>version</replaceable>/nixpkgs-<replaceable>version</replaceable>.tar.bz2
-$ tar xfj nixpkgs-<replaceable>version</replaceable>.tar.bz2</screen>
+<screen>
+$ nix-channel --add \
+    http://nix.cs.uu.nl/dist/nix/channels-v3/nixpkgs-unstable</screen>

-        This will unpack the distribution into a directory
-        <filename>nixpkgs-<replaceable>version</replaceable>/</filename>.
-      </para>
-    </listitem>
+</para></listitem>

-    <listitem>
-      <para>
-        Pull the Nix cache.  This ensures that when you install
-        packages they are downloaded in pre-built form from the
-        network, rather than built from source.
+<listitem><para>Download the latest Nix expressions available in the channel.
+<screen>
+$ nix-channel --update</screen>

-        <screen>
-$ nix-pull http://<replaceable>...</replaceable>/nix/nixpkgs-<replaceable>version</replaceable>/MANIFEST</screen>
+Note that this in itself doesn't download any packages, it just
+downloads the Nix expressions that build them and stores them
+somewhere (under <filename>~/.nix-defexpr</filename>, in case you're
+curious).  Also, it registers the fact that pre-built binaries are
+available remotely.</para></listitem>

-      </para>
+<listitem><para>See what installable packages are currently available
+in the channel:

-      <para>
-        Note that currently we only pre-build for Linux on x86
-        platforms.
-      </para>
-        
-    </listitem>
-        
-    <listitem>
-      <para>
-        See what's available:
-
-        <screen>
-$ nix-env -qaf nixpkgs-<replaceable>version</replaceable>/
-MozillaFirebird-0.7
-hello-2.1.1
+<screen>
+$ nix-env -qa ’*’ <lineannotation>(mind the quotes!)</lineannotation>
 docbook-xml-4.2
+firefox-1.0pre-PR-0.10.1
+hello-2.1.1
 libxslt-1.1.0
 <replaceable>...</replaceable></screen>

-      </para>
-    </listitem>
+</para></listitem>

-    <listitem>
-      <para>
-        Install some packages:
+<listitem><para>Install some packages from the channel:
        
-        <screen>
-$ nix-env -iBf nixpkgs-<replaceable>version</replaceable>/ hello MozillaFirebird <replaceable>...</replaceable> </screen>
+<screen>
+$ nix-env -i hello firefox <replaceable>...</replaceable> </screen>

-      </para>
-    </listitem>
+This should download pre-built packages; it should not build them
+locally (if it does, something went wrong).</para></listitem>

-    <listitem>
-      <para>
-        Test that they work:
+<listitem><para>Test that they work:

-        <screen>
+<screen>
 $ which hello
 /home/eelco/.nix-profile/bin/hello
 $ hello
 Hello, world!
-$ MozillaFirebird
+$ firefox
 <lineannotation>(read Slashdot or something)</lineannotation></screen>

-      </para>
-    </listitem>
+</para></listitem>
    
-    <listitem>
-      <para>
-        Uninstall a package:
+<listitem><para>Uninstall a package:

-        <screen>
+<screen>
 $ nix-env -e hello</screen>

-      </para>
-    </listitem>
+</para></listitem>

-    <listitem>
-      <para>
-        If a new release of <literal>nixpkgs</literal> comes along,
-        you can upgrade all installed packages to the latest versions
-        by downloading and unpacking the new release and doing:
+<listitem><para>To keep up-to-date with the channel, do:

-        <screen>
-$ nix-env -uBf nixpkgs-<replaceable>version</replaceable>/ '*'</screen>
+<screen>
+$ nix-channel --update
+$ nix-env -u '*'</screen>

-      </para>
-    </listitem>
+The latter command will upgrade each installed package for which there
+is a “newer” version (as determined by comparing the version
+numbers).</para></listitem>

-    <listitem>
-      <para>
-        You should periodically run the Nix garbage collector to get
-        rid of unused packages, since uninstalls or upgrades don't
-        actual delete them:
+<listitem><para>You can also install specific packages directly from
+your web browser.  For instance, you can go to <link
+xlink:href="http://nix.cs.uu.nl/dist/nix/nixpkgs-unstable-latest/" />
+and click on any link for the individual packages for your platform.
+Associate <literal>application/nix-package</literal> with the program
+<filename>/nix/bin/nix-install-package</filename>.  A window should
+appear asking you whether it’s okay to install the package.  Say
+<literal>Y</literal>.  The package and all its dependencies will be
+installed.</para></listitem>

-        <screen>
-$ nix-collect-garbage | xargs nix-store --delete</screen>
+<listitem><para>If you're unhappy with the result of a
+<command>nix-env</command> action (e.g., an upgraded package turned
+out not to work properly), you can go back:

-      </para>
-    </listitem>
+<screen>
+$ nix-env --rollback</screen>

-  </orderedlist>
+</para></listitem>

-</chapter>
+<listitem><para>You should periodically run the Nix garbage collector
+to get rid of unused packages, since uninstalls or upgrades don't
+actually delete them:
+
+<screen>
+$ nix-collect-garbage -d</screen>
+
+<!--
+The first command deletes old “generations” of your profile (making
+rollbacks impossible, but also making the packages in those old
+generations available for garbage collection), while the second
+command actually deletes them.-->
+
+</para></listitem>
+
+</orderedlist>
+
+</chapter>
--- a/doc/manual/quote-literals.xsl
+++ b/doc/manual/quote-literals.xsl
@@ -0,0 +1,44 @@
+<?xml version="1.0"?>
+
+<xsl:stylesheet
+  version="1.0"
+  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+  xmlns:str="http://exslt.org/strings"
+  extension-element-prefixes="str">
+
+  <xsl:output method="xml"/>
+  
+  <xsl:template match="function|command|literal|varname|filename|option|quote">`<xsl:apply-templates/>'</xsl:template>
+  
+  <xsl:template match="token"><xsl:text>    </xsl:text><xsl:apply-templates /><xsl:text>
+</xsl:text></xsl:template>
+
+  <xsl:template match="screen|programlisting">
+    <screen><xsl:apply-templates select="str:split(., '&#xA;')" /></screen>
+  </xsl:template>
+
+  <xsl:template match="section[following::section]">
+    <section>
+      <xsl:apply-templates />
+      <screen><xsl:text>
+      </xsl:text></screen>        
+    </section>
+  </xsl:template>
+
+  <xsl:template match="*">
+    <xsl:element name="{name(.)}" namespace="{namespace-uri(.)}">
+      <xsl:copy-of select="namespace::*" />
+      <xsl:for-each select="@*">
+	<xsl:attribute name="{name(.)}" namespace="{namespace-uri(.)}">
+	  <xsl:value-of select="."/>
+	</xsl:attribute>
+      </xsl:for-each>
+      <xsl:apply-templates/>
+    </xsl:element>
+  </xsl:template>
+
+  <xsl:template match="text()">
+    <xsl:value-of select="translate(., '‘’“”—', concat(&quot;`'&quot;, '&quot;&quot;-'))" />
+  </xsl:template>
+  
+</xsl:stylesheet>
--- a/doc/manual/release-notes.xml
+++ b/doc/manual/release-notes.xml
--- a/doc/manual/schemas.xml
+++ b/doc/manual/schemas.xml
@@ -1,4 +1,4 @@
 <?xml version="1.0"?>
 <locatingRules xmlns="http://thaiopensource.com/ns/locating-rules/1.0">
-  <uri pathSuffix=".xml" typeId="DocBook"/>
+  <uri pattern="*.xml" typeId="DocBook"/>
 </locatingRules>
--- a/doc/manual/style.css
+++ b/doc/manual/style.css
@@ -10,7 +10,6 @@ body
 {
    font-family: sans-serif;
    background: white;
-  
    margin: 2em 1em 2em 1em;
 }

@@ -34,16 +33,33 @@ h2 /* chapters, appendices, subtitle */
 div.chapter > div.titlepage h2, div.appendix > div.titlepage h2 
 { 
    margin-top: 1.5em;
-/*    border-top: solid #005aa0; */
 }

-div.sect1 h2 /* sections */
+div.section > div.titlepage h2 /* sections */
 {
    font-size: 150%;
+    margin-top: 1.5em;
+}
+
+h3 /* subsections */
+{
+    font-size: 125%;
+}
+
+div.simplesect h2
+{
+    font-size: 110%;
+}
+
+div.appendix h3
+{
+    font-size: 150%;
+    margin-top: 1.5em;
 }

 div.refnamediv h2, div.refsynopsisdiv h2, div.refsection h2 /* refentry parts */
 {
+    margin-top: 1.4em;
    font-size: 125%;
 }

@@ -52,30 +68,23 @@ div.refsection h3
    font-size: 110%;
 }

-h3 /* subsections */
-{
-    font-size: 125%;
-}
-
-

 /***************************************************************************
-                               Program listings:
+                               Examples:
 ***************************************************************************/

 div.example
 {
    border: 1px solid #6185a0;
    padding: 6px 6px;
-    margin-left: 3em;
-    margin-right: 3em;
-    background: #eeeeee;
+    margin-left: 1.5em;
+    margin-right: 1.5em;
+    background: #f4f4f8;
 }

-pre.programlisting
+div.example p.title
 {
-    color: #600000;
-    font-family: monospace;
+    margin-top: 0em;
 }


@@ -83,39 +92,69 @@ pre.programlisting
                            Screen dumps:
 ***************************************************************************/

-pre.screen
+pre.screen, pre.programlisting
 {
    border: 1px solid #6185a0;
-    padding: 6px 6px;
-    margin-left: 3em;
-    margin-right: 3em;
+    padding: 3px 3px;
+    margin-left: 1.5em;
+    margin-right: 1.5em;
    color: #600000;
-    background: #eeeeee;
+    background: #f4f4f8;
    font-family: monospace;
    /* font-size: 90%; */
 }

+div.example pre.programlisting
+{
+    border: 0px;
+    padding: 0 0;
+    margin: 0 0 0 0;
+}
+

 /***************************************************************************
                               Notes, warnings etc:
 ***************************************************************************/

-.note,.warning
+.note, .warning
 {
    border: 1px solid #6185a0;
-    padding: 0px 1em;
+    padding: 3px 3px;
+    margin-left: 1.5em;
+    margin-right: 1.5em;
+    margin-bottom: 1em;
+    padding: 0.3em 0.3em 0.3em 0.3em;
    background: #fffff5;
 }

-div.note,div.warning
+div.note, div.warning
 {
    font-style: italic;
 }

-div.note h3,div.warning h3
+div.note h3, div.warning h3
 {
    color: red;
-    text-decoration: underline;
+    font-size: 100%;
+//    margin: 0 0 0 0;
+    padding-right: 0.5em;
+    display: inline;
+}
+
+div.note p, div.warning p
+{
+    margin-bottom: 0em;
+}
+
+div.note h3 + p, div.warning h3 + p
+{
+    display: inline;
+}
+
+div.note h3
+{
+    color: blue;
+    font-size: 100%;
 }

 div.navfooter *
@@ -148,7 +187,7 @@ a:hover { background: #ffffcd; }
                               Special elements:
 ***************************************************************************/

-tt
+tt, code
 {
    color: #400000;
 }
@@ -159,9 +198,19 @@ tt
    
 }

-div.variablelist dd
+div.variablelist dd p, div.glosslist dd p
 {
-    margin-bottom: 1em;
+    margin-top: 0em;
+}
+
+div.variablelist dd, div.glosslist dd
+{
+    margin-left: 1.5em;
+}
+
+div.glosslist dt
+{
+    font-style: italic;
 }

 .default
@@ -223,4 +272,17 @@ div.epigraph
 table.productionset table.productionset
 {
    font-family: monospace;
-}
+}
+
+strong.command
+{
+//    font-family: monospace;
+//    font-style: italic;
+//    font-weight: normal;
+    color: #400000;
+}
+
+div.calloutlist td
+{
+    padding-bottom: 1em;
+}
--- a/doc/manual/troubleshooting.xml
+++ b/doc/manual/troubleshooting.xml
@@ -1,14 +1,202 @@
-<appendix>
-  <title>Troubleshooting</title>
+<appendix xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink">
+
+<title>Troubleshooting</title>
+
+
+<para>This section provides solutions for some common problems.  See
+the <link xlink:href="https://bugs.cs.uu.nl/browse/NIX">Nix
+bug tracker</link> for a list of currently known issues.</para>
+
+
+<section><title>Berkeley DB: <quote>Cannot allocate memory</quote></title>
+
+<para>Symptom: Nix operations (in particular the
+<command>nix-store</command> operations <option>--gc</option>,
+<option>--verify</option>, and <option>--clear-substitutes</option> —
+the latter being called by <command>nix-channel --update</command>)
+failing:
+
+<screen>
+$ nix-store --verify
+error: Db::del: Cannot allocate memory</screen>
+
+</para>
+
+<para>Possible solution: make sure that no Nix processes are running,
+then do:
+
+<screen>
+$ cd /nix/var/nix/db
+$ rm __db.00*</screen>
+
+</para>
+
+</section>
+
+
+<section><title>Berkeley DB gives weird error messages</title>
+
+<para>Symptom: you get error messages such as
+
+<screen>
+Berkeley DB message: Finding last valid log LSN: file: 1 offset 28
+Berkeley DB error: file validpaths (meta pgno = 0) has LSN [483][34721].
+Berkeley DB error: end of log is [1][28]
+Berkeley DB error: /nix/var/nix/db/validpaths: unexpected file type or format</screen>
+
+or other weird Berkeley DB errors, and they don’t go away (i.e.,
+automatic recovery doesn’t work).  This may be the case after a system
+crash.</para>
+
+<para>Solution: first try to run <command>db_recover</command> and
+then <link linkend='refsec-nix-store-verify'><command>nix-store
+--verify</command></link>:
+
+<screen>
+$ db_recover -h /nix/var/nix/db
+$ nix-store --verify</screen>
+
+(Make sure that you have the right version of
+<command>db_recover</command>, namely, Berkeley DB 4.4 for Nix 0.10,
+and 4.5 for Nix 0.11.)</para>
+
+<para>If that doesn’t work, it’s time to bring out the big guns:
+
+<screen>
+$ cd /nix/var/nix
+$ cp -pr db db-backup  <lineannotation>(making a backup just in case)</lineannotation>
+$ cd db
+$ rm __db.* log*  <lineannotation>(removing the Berkeley DB environment)</lineannotation>
+$ mkdir tmp
+$ for i in *; do db_dump $i | (cd tmp &amp;&amp; db_load $i); done 
+<lineannotation>(ignore error messages about non-database files like “reserved”)</lineannotation>
+$ mv tmp/* .
+$ nix-store --verify</screen>
+
+</para>
+
+</section>
+
+
+<section><title>Berkeley DB out of locks</title>
+
+<para>It is possible, especially in <command>nix-store
+--verify</command> or when running the garbage collector, to run out
+of Berkeley DB locks, like this:
+
+<screen>
+$ nix-store --verify
+checking path existence
+checking path realisability
+checking the derivers table
+checking the references table
+Berkeley DB error: Lock table is out of available object entries
+error: Db::get: Cannot allocate memory</screen>
+
+</para>
+
+<para>A workaround is to increase the number of locks that Berkeley DB
+allocates.  (The real solution would be for Nix to not use so many
+locks.)  This can be done by putting the following in the file
+<filename>/nix/var/nix/db/<link
+xlink:href="http://www.oracle.com/technology/documentation/berkeley-db/db/ref/env/db_config.html">DB_CONFIG</link></filename>:
+
+<programlisting>
+set_lk_max_locks   100000
+set_lk_max_lockers 100000
+set_lk_max_objects 100000
+</programlisting>
+
+(Increase these numbers if necessary.)  Then make sure that there are
+no running Nix processes and delete the Berkeley DB environment:
+
+<screen>
+$ rm /nix/var/nix/db/__db.*</screen>
+
+The Berkeley DB environment is automatically recreated with the new
+limits when you run any Nix command.</para>
+
+</section>
+
+
+<section><title>Collisions in <command>nix-env</command></title>
+
+<para>Symptom: when installing or upgrading, you get an error message such as
+
+<screen>
+$ nix-env -i docbook-xml
+...
+adding /nix/store/s5hyxgm62gk2...-docbook-xml-4.2
+collission between `/nix/store/s5hyxgm62gk2...-docbook-xml-4.2/xml/dtd/docbook/calstblx.dtd'
+  and `/nix/store/06h377hr4b33...-docbook-xml-4.3/xml/dtd/docbook/calstblx.dtd'
+  at /nix/store/...-builder.pl line 62.</screen>
+
+</para>
+
+<para>The cause is that two installed packages in the user environment
+have overlapping filenames (e.g.,
+<filename>xml/dtd/docbook/calstblx.dtd</filename>.  This usually
+happens when you accidentally try to install two versions of the same
+package.  For instance, in the example above, the Nix Packages
+collection contains two versions of <literal>docbook-xml</literal>, so
+<command>nix-env -i</command> will try to install both.  The default
+user environment builder has no way to way to resolve such conflicts,
+so it just gives up.</para>
+
+<para>Solution: remove one of the offending packages from the user
+environment (if already installed) using <command>nix-env
+-e</command>, or specify exactly which version should be installed
+(e.g., <literal>nix-env -i docbook-xml-4.2</literal>).</para>
+
+<para>Alternatively, you can modify the user environment builder
+script (in
+<filename><replaceable>prefix</replaceable>/share/nix/corepkgs/buildenv/builder.pl</filename>)
+to implement some conflict resolution policy.  E.g., the script could
+be modified to rename conflicting file names, or to pick one over the
+other.</para>
+
+</section>
+
+
+<section><title><quote>Too many links</quote> error in the Nix
+store</title>
+
+
+<para>Symptom: when building something, you get an error message such as
+
+<screen>
+...
+<literal>mkdir: cannot create directory `/nix/store/<replaceable>name</replaceable>': Too many links</literal></screen>
+
+</para>
+
+<para>This is usually because you have more than 32,000 subdirectories
+in <filename>/nix/store</filename>, as can be seen using <command>ls
+-l</command>:
+
+<screen>
+$ ls -l /nix/store
+drwxrwxrwt 32000 nix nix 4620288 Sep 8 15:08 store</screen>
+
+The <literal>ext2</literal> file system is limited to a inode link
+count of 32,000 (each subdirectory increasing the count by one).
+Furthermore, the <literal>st_nlink</literal> field of the
+<function>stat</function> system call is a 16-bit value.</para>
+
+<para>This only happens on very large Nix installations (such as build
+machines).</para>
+
+<para>Quick solution: run the garbage collector.</para>
+
+<para>Real solution: put the Nix store on a file system that supports
+more than 32,000 subdirectories per directory, such as ReiserFS.
+(This doesn’t solve the <literal>st_nlink</literal> limit, but
+ReiserFS lies to the kernel by reporting a link count of 1 if it
+exceeds the limit.)</para>
+
+</section>
+  
+

-  <para>
-    (Nothing.)
-  </para>
-	
 </appendix>
-
-<!--
-local variables:
-sgml-parent-document: ("book.xml" "appendix")
-end:
-->
--- a/doc/manual/writing-nix-expressions.xml
+++ b/doc/manual/writing-nix-expressions.xml
--- a/doc/signing.txt
+++ b/doc/signing.txt
@@ -0,0 +1,24 @@
+Generate a private key:
+
+$ (umask 277 && openssl genrsa -out /nix/etc/nix/signing-key.sec 2048)
+
+The private key should be kept secret (only readable to the Nix daemon
+user).
+
+
+Generate the corresponding public key:
+
+$ openssl rsa -in /nix/etc/nix/signing-key.sec -pubout > /nix/etc/nix/signing-key.pub
+
+The public key should be copied to all machines to which you want to
+export store paths.
+
+
+Signing:
+
+$ nix-hash --type sha256 --flat svn.nar | openssl rsautl -sign -inkey mykey.sec > svn.nar.sign
+
+
+Verifying a signature:
+
+$ test "$(nix-hash --type sha256 --flat svn.nar)" = "$(openssl rsautl -verify -inkey mykey.pub -pubin -in svn.nar.sign)"
--- a/externals/Makefile.am
+++ b/externals/Makefile.am
@@ -1,16 +1,17 @@
 # Berkeley DB

-DB = db-4.2.52
+DB = db-4.5.20

 $(DB).tar.gz:
 	@echo "Nix requires Berkeley DB to build."
-	@echo "Please download version 4.2.52 from"
-	@echo "  http://www.sleepycat.com/update/snapshot/db-4.2.52.tar.gz"
+	@echo "Please download version 4.5.20 from"
+	@echo "  http://download-east.oracle.com/berkeley-db/db-4.5.20.tar.gz"
 	@echo "and place it in the externals/ directory."
 	false

 $(DB): $(DB).tar.gz
-	gunzip < $(DB).tar.gz | tar xvf -
+	gunzip < $(srcdir)/$(DB).tar.gz | tar xvf -
+	(cd $(DB) && $(patch) -p1) < $(srcdir)/bdb-cygwin.patch

 have-db:
 	$(MAKE) $(DB)
@@ -26,25 +27,25 @@ build-db: have-db
 	 ../dist/configure --prefix=$$pfx/inst-bdb \
 	 --enable-cxx --disable-shared --disable-cryptography \
         --disable-replication --disable-verify && \
-	make && \
-	make install)
+	$(MAKE) && \
+	$(MAKE) install_include install_lib)
 	touch build-db
 endif


 # CWI ATerm

-ATERM = aterm-2.1
+ATERM = aterm-2.4.2-fixes-r2

-$(ATERM).tar.gz:
+$(ATERM).tar.bz2:
 	@echo "Nix requires the CWI ATerm library to build."
-	@echo "Please download version 2.1 from"
-	@echo "  http://www.cwi.nl/projects/MetaEnv/aterm/aterm-2.1.tar.gz"
+	@echo "Please download version 2.4.2-fixes-r2 from"
+	@echo "  http://losser.st-lab.cs.uu.nl/~eelco/dist/aterm-2.4.2-fixes-r2.tar.bz2"
 	@echo "and place it in the externals/ directory."
 	false

-$(ATERM): $(ATERM).tar.gz
-	gunzip < $(ATERM).tar.gz | tar xvf -
+$(ATERM): $(ATERM).tar.bz2
+	bunzip2 < $(srcdir)/$(ATERM).tar.bz2 | tar xvf -

 have-aterm:
 	$(MAKE) $(ATERM)
@@ -57,17 +58,52 @@ build-aterm: have-aterm
 	(pfx=`pwd` && \
 	cd $(ATERM) && \
 	CC="$(CC)" ./configure --prefix=$$pfx/inst-aterm \
-     --with-cflags="-DNDEBUG -DXGC_VERBOSE -DXHASHPEM -DWITH_STATS $(CFLAGS)" && \
-	make && \
-	make install)
+	  --disable-shared --enable-static && \
+	$(MAKE) && \
+	$(MAKE) install)
 	touch build-aterm
 endif


-all: build-db build-aterm
+# bzip2

-EXTRA_DIST = $(DB).tar.gz $(ATERM).tar.gz
+BZIP2 = bzip2-1.0.4
+
+$(BZIP2).tar.gz:
+	@echo "Nix requires bzip2 to build."
+	@echo "Please download version 1.0.4 from"
+	@echo "  http://www.bzip.org/1.0.4/bzip2-1.0.4.tar.gz"
+	@echo "and place it in the externals/ directory."
+	false
+
+$(BZIP2): $(BZIP2).tar.gz
+	gunzip < $(srcdir)/$(BZIP2).tar.gz | tar xvf -
+
+have-bzip2:
+	$(MAKE) $(BZIP2)
+	touch have-bzip2
+
+if HAVE_BZIP2
+build-bzip2:
+else
+build-bzip2: have-bzip2
+	(pfx=`pwd` && \
+	cd $(BZIP2) && \
+	$(MAKE) && \
+	$(MAKE) install PREFIX=$$pfx/inst-bzip2)
+	touch build-bzip2
+
+install:
+	mkdir -p $(DESTDIR)${bzip2_bin}
+	$(INSTALL_PROGRAM) $(bzip2_bin_test)/bzip2 $(bzip2_bin_test)/bunzip2 $(DESTDIR)${bzip2_bin}
+endif
+
+
+all: build-db build-aterm build-bzip2
+
+EXTRA_DIST = $(DB).tar.gz $(ATERM).tar.bz2 $(BZIP2).tar.gz \
+  bdb-cygwin.patch

 ext-clean:
 	$(RM) -f have-db build-db have-aterm build-aterm
-	$(RM) -rf $(DB) $(ATERM)
+	$(RM) -rf $(DB) $(ATERM) $(BZIP2)
--- a/externals/bdb-cygwin.patch
+++ b/externals/bdb-cygwin.patch
@@ -0,0 +1,22 @@
+diff -rc db-4.5.20-orig/os/os_flock.c db-4.5.20/os/os_flock.c
+*** db-4.5.20-orig/os/os_flock.c	2006-10-13 12:36:12.000000000 +0200
+--- db-4.5.20/os/os_flock.c	2006-10-13 12:40:11.000000000 +0200
+***************
+*** 30,35 ****
+--- 30,44 ----
+  
+  	DB_ASSERT(dbenv, F_ISSET(fhp, DB_FH_OPENED) && fhp->fd != -1);
+  
+ #ifdef __CYGWIN__
+ 	/*
+ 	 * Windows file locking interferes with read/write operations, so we
+ 	 * map the ranges to an area past the end of the file.
+ 	 */
+ 	DB_ASSERT(dbenv, offset < (off_t) 1 << 62);
+ 	offset += (off_t) 1 << 62;
+ #endif
+ 
+  	fl.l_start = offset;
+  	fl.l_len = 1;
+  	fl.l_type = acquire ? F_WRLCK : F_UNLCK;
+Only in db-4.5.20/os: os_flock.c~
--- a/install_full.sh
+++ b/install_full.sh
@@ -0,0 +1,67 @@
+#! /bin/sh -e
+
+make clean				# comment this out when needed !!!
+
+export nixstatepath=/nixstate2/nix
+export ACLOCAL_PATH=/home/wouterdb/.nix-profile/share/aclocal
+
+if [ "$1" = "full" ]; then
+  nix-env-all-pkgs.sh -i gcc
+  nix-env-all-pkgs.sh -i gnum4
+  nix-env-all-pkgs.sh -i autoconf
+  nix-env-all-pkgs.sh -i automake
+  nix-env-all-pkgs.sh -i gnused
+  nix-env-all-pkgs.sh -i db4
+  nix-env-all-pkgs.sh -i aterm
+  nix-env-all-pkgs.sh -i bzip2
+  nix-env-all-pkgs.sh -i flex
+  nix-env-all-pkgs.sh -i bsdiff
+  nix-env-all-pkgs.sh -i libtool
+  nix-env-all-pkgs.sh -i docbook5
+  nix-env-all-pkgs.sh -i docbook5-xsl
+  nix-env-all-pkgs.sh -i bison
+  nix-env-all-pkgs.sh -i gdb			#optional for debugging
+  nix-env-all-pkgs.sh -i gnupatch
+  nix-env-all-pkgs.sh -i gnumake
+  nix-env-all-pkgs.sh -i ext3cow-tools
+  nix-env-all-pkgs.sh -i e3cfsprogs
+  nix-env-all-pkgs.sh -i rsync  
+fi
+
+if [ "$1" = "full" ] || [ "$1" = "auto" ]; then
+  export AUTOCONF=autoconf
+  export AUTOHEADER=autoheader
+  export AUTOMAKE=automake
+  autoconf
+  autoreconf -f
+  aclocal
+  autoheader
+  automake
+fi
+
+./bootstrap.sh
+
+./configure --with-aterm=$HOME/.nix-profile \
+            --with-bzip2=$HOME/.nix-profile \
+            --with-bdb=$HOME/.nix-profile \
+            --with-docbook-xsl=$HOME/.nix-profile \
+            --with-docbook-rng=/home/wouterdb/.nix-profile/xml/rng/docbook \
+            --with-docbook-xsl=/home/wouterdb/.nix-profile/xml/xsl/docbook \
+            --prefix=$nixstatepath \
+            --with-store-dir=/nix/store \
+	    	--with-store-state-dir=/nix/state \
+            --with-ext3cow-header=/nix/store/2sm0h2xd1zsm5had53q1pvzmnsn8fy8k-linux-2.6.21/lib/modules/2.6.21-ck1-default/build/include/linux/ext3cow_fs.h \
+            --localstatedir=/nix/var
+
+#Options from the nix expr
+#--disable-init-state
+#--with-store-dir=/nix/store 
+#--localstatedir=/nix/var
+#--with-aterm=/nix/store/pkmzbb613wa8cwngx8jjb5jaic8yhyzs-aterm-2.4.2-fixes
+#--with-bdb=/nix/store/4yv4j1cd7i5j3mhs5wpc1kzlz1cj8n82-db4-4.5.20
+#--with-bzip2=/nix/store/dh0mdgkvhv3pwrf8zp58phpzn9rcm49r-bzip2-1.0.3
+#--disable-init-state
+
+
+echo "New state nix version by wouter ..." > doc/manual/NEWS.txt
+make
--- a/install_install_d.sh
+++ b/install_install_d.sh
@@ -0,0 +1,16 @@
+#! /bin/sh -e
+
+if [ $(whoami) = "root" ]
+then
+
+su - wouterdb -c "cd /home/wouterdb/dev/nix-state/; make"
+make install
+chown -R wouterdb.wouterdb /nixstate2/nix/
+
+./restartDaemon.sh
+
+else
+  echo "You must be ROOT to run this script."
+  exit 0
+fi
+
--- a/install_make.sh
+++ b/install_make.sh
@@ -0,0 +1,5 @@
+#! /bin/sh -e
+
+make
+
+
--- a/make/examples/aterm/aterm/default.nix
+++ b/make/examples/aterm/aterm/default.nix
@@ -0,0 +1,30 @@
+{sharedLib ? true}:
+
+rec {
+
+  inherit (import ../../../lib) compileC makeLibrary;
+
+  sources = [
+    ./afun.c
+    ./aterm.c
+    ./bafio.c
+    ./byteio.c
+    ./gc.c
+    ./hash.c
+    ./list.c
+    ./make.c
+    ./md5c.c
+    ./memory.c
+    ./tafio.c
+    ./version.c
+  ];
+
+  compile = main: compileC {inherit main sharedLib;};
+
+  libATerm = makeLibrary {
+    libraryName = "ATerm";
+    objects = map compile sources;
+    inherit sharedLib;
+  };
+
+}
--- a/make/examples/aterm/default.nix
+++ b/make/examples/aterm/default.nix
@@ -0,0 +1 @@
+import test/default.nix
--- a/make/examples/aterm/test/default.nix
+++ b/make/examples/aterm/test/default.nix
@@ -0,0 +1,15 @@
+with (import ../../../lib);
+
+let {
+  inherit (import ../aterm {}) libATerm;
+
+  compileTest = main: link {
+    objects = [(compileC {inherit main; localIncludePath = [ ../aterm ];})];
+    libraries = libATerm;
+  };
+
+  body = [
+    (compileTest ./fib.c)
+    (compileTest ./primes.c)
+  ];
+}
--- a/make/examples/default.nix
+++ b/make/examples/default.nix
@@ -0,0 +1,6 @@
+[ (import ./trivial)
+  (import ./simple-header)
+  (import ./not-so-simple-header)
+  (import ./not-so-simple-header-auto)
+  (import ./aterm)
+]
--- a/make/examples/not-so-simple-header-auto/bar/hello.h
+++ b/make/examples/not-so-simple-header-auto/bar/hello.h
@@ -0,0 +1 @@
+#define WHAT "World"
--- a/make/examples/not-so-simple-header-auto/default.nix
+++ b/make/examples/not-so-simple-header-auto/default.nix
@@ -0,0 +1,13 @@
+with import ../../lib;
+
+let {
+
+  hello = link {programName = "hello"; objects = compileC {
+    main = ./foo/hello.c;
+    localIncludes = "auto";
+  };};
+
+#  body = findIncludes {main = ./foo/hello.c;};
+
+  body = [hello];
+}
--- a/make/examples/not-so-simple-header-auto/foo/fnord/indirect.h
+++ b/make/examples/not-so-simple-header-auto/foo/fnord/indirect.h
@@ -0,0 +1,3 @@
+#define HELLO "Hello"
+
+#include "../../bar/hello.h"
--- a/make/examples/not-so-simple-header-auto/foo/hello.c
+++ b/make/examples/not-so-simple-header-auto/foo/hello.c
@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+#include "fnord/indirect.h"
+
+int main(int argc, char * * argv)
+{
+    printf(HELLO " " WHAT "\n");
+    return 0;
+}
--- a/make/examples/not-so-simple-header/bar/hello.h
+++ b/make/examples/not-so-simple-header/bar/hello.h
@@ -0,0 +1 @@
+#define WHAT "World"
--- a/make/examples/not-so-simple-header/default.nix
+++ b/make/examples/not-so-simple-header/default.nix
@@ -0,0 +1,14 @@
+let {
+
+  inherit (import ../../lib) compileC link;
+
+  hello = link {programName = "hello"; objects = compileC {
+    main = ./foo/hello.c;
+    localIncludes = [
+      [./foo/fnord/indirect.h "fnord/indirect.h"]
+      [./bar/hello.h "fnord/../../bar/hello.h"]
+    ];
+  };};
+
+  body = [hello];
+}
--- a/make/examples/not-so-simple-header/foo/fnord/indirect.h
+++ b/make/examples/not-so-simple-header/foo/fnord/indirect.h
@@ -0,0 +1,3 @@
+#define HELLO "Hello"
+
+#include "../../bar/hello.h"
--- a/make/examples/not-so-simple-header/foo/hello.c
+++ b/make/examples/not-so-simple-header/foo/hello.c
@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+#include "fnord/indirect.h"
+
+int main(int argc, char * * argv)
+{
+    printf(HELLO " " WHAT "\n");
+    return 0;
+}
--- a/make/examples/simple-header/default.nix
+++ b/make/examples/simple-header/default.nix
@@ -0,0 +1,11 @@
+let {
+
+  inherit (import ../../lib) compileC link;
+
+  hello = link {objects = compileC {
+    main = ./hello.c;
+    localIncludes = [ [./hello.h "hello.h"] ];
+  };};
+
+  body = [hello];
+}
--- a/make/examples/simple-header/hello.c
+++ b/make/examples/simple-header/hello.c
@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+#include "hello.h"
+
+int main(int argc, char * * argv)
+{
+    printf("Hello " WHAT "\n");
+    return 0;
+}
--- a/make/examples/simple-header/hello.h
+++ b/make/examples/simple-header/hello.h
@@ -0,0 +1 @@
+#define WHAT "World"
--- a/make/examples/trivial/default.nix
+++ b/make/examples/trivial/default.nix
@@ -0,0 +1,8 @@
+let {
+
+  inherit (import ../../lib) compileC link;
+
+  hello = link {objects = compileC {main = ./hello.c;};};
+
+  body = [hello];
+}
--- a/make/examples/trivial/hello.c
+++ b/make/examples/trivial/hello.c
@@ -0,0 +1,7 @@
+#include <stdio.h>
+
+int main(int argc, char * * argv)
+{
+    printf("Hello World\n");
+    return 0;
+}
--- a/make/lib/compile-c.sh
+++ b/make/lib/compile-c.sh
@@ -0,0 +1,73 @@
+. $stdenv/setup
+
+mainName=$(basename $main | cut -c34-)
+
+echo "compiling \`$mainName'..."
+
+# Turn $localIncludes into an array.
+localIncludes=($localIncludes)
+
+# Determine how many `..' levels appear in the header file references.
+# E.g., if there is some reference `../../foo.h', then we have to
+# insert two extra levels in the directory structure, so that `a.c' is
+# stored at `dotdot/dotdot/a.c', and a reference from it to
+# `../../foo.h' resolves to `dotdot/dotdot/../../foo.h' == `foo.h'.
+n=0
+maxDepth=0
+for ((n = 0; n < ${#localIncludes[*]}; n += 2)); do
+    target=${localIncludes[$((n + 1))]}
+
+    # Split the target name into path components using some IFS magic.
+    savedIFS="$IFS"
+    IFS=/
+    components=($target)
+    depth=0
+    for ((m = 0; m < ${#components[*]}; m++)); do
+        c=${components[m]}
+        if test "$c" = ".."; then
+            depth=$((depth + 1))
+        fi
+    done
+    IFS="$savedIFS"
+
+    if test $depth -gt $maxDepth; then
+        maxDepth=$depth;
+    fi
+done
+
+# Create the extra levels in the directory hierarchy.
+prefix=
+for ((n = 0; n < maxDepth; n++)); do
+    prefix="dotdot/$prefix"
+done
+
+# Create symlinks to the header files.
+for ((n = 0; n < ${#localIncludes[*]}; n += 2)); do
+    source=${localIncludes[n]}
+    target=${localIncludes[$((n + 1))]}
+
+    # Create missing directories.  We use IFS magic to split the path
+    # into path components.
+    savedIFS="$IFS"
+    IFS=/
+    components=($prefix$target)
+    fullPath=(.)
+    for ((m = 0; m < ${#components[*]} - 1; m++)); do
+        fullPath=("${fullPath[@]}" ${components[m]})
+        if ! test -d "${fullPath[*]}"; then
+            mkdir "${fullPath[*]}"
+        fi
+    done
+    IFS="$savedIFS"
+    
+    ln -sf $source $prefix$target
+done
+
+# Create a symlink to the main file.
+if ! test "$(readlink $prefix$mainName)" = $main; then
+    ln -s $main $prefix$mainName
+fi
+
+mkdir $out
+test "$prefix" && cd $prefix
+gcc -Wall $cFlags -c $mainName -o $out/$mainName.o
--- a/make/lib/default.nix
+++ b/make/lib/default.nix
@@ -0,0 +1,69 @@
+rec {
+
+  # Should point at your Nixpkgs installation.
+  pkgPath = ./pkgs;
+
+  pkgs = import (pkgPath + /system/all-packages.nix) {};
+
+  stdenv = pkgs.stdenv;
+  
+
+  compileC =
+  { main
+  , localIncludes ? "auto"
+  , localIncludePath ? []
+  , cFlags ? ""
+  , sharedLib ? false
+  }:
+  stdenv.mkDerivation {
+    name = "compile-c";
+    builder = ./compile-c.sh;
+    
+    localIncludes =
+      if localIncludes == "auto" then
+        dependencyClosure {
+          scanner = main:
+            import (findIncludes {
+              inherit main;
+            });
+          searchPath = localIncludePath;
+          startSet = [main];
+        }
+      else
+        localIncludes;
+        
+    inherit main;
+    
+    cFlags = [
+      cFlags
+      (if sharedLib then ["-fpic"] else [])
+      (map (p: "-I" + (relativise (dirOf main) p)) localIncludePath)
+    ];
+  };
+
+  
+  findIncludes = {main}: stdenv.mkDerivation {
+    name = "find-includes";
+    realBuilder = pkgs.perl ~ "bin/perl";
+    args = [ ./find-includes.pl ];
+    inherit main;
+  };
+
+    
+  link = {objects, programName ? "program", libraries ? []}: stdenv.mkDerivation {
+    name = "link";
+    builder = ./link.sh;
+    inherit objects programName libraries;
+  };
+
+  
+  makeLibrary = {objects, libraryName ? [], sharedLib ? false}:
+  # assert sharedLib -> fold (obj: x: assert obj.sharedLib && x) false objects
+  stdenv.mkDerivation {
+    name = "library";
+    builder = ./make-library.sh;
+    inherit objects libraryName sharedLib;
+  };
+
+  
+}
--- a/make/lib/find-includes.pl
+++ b/make/lib/find-includes.pl
@@ -0,0 +1,21 @@
+use strict;
+
+my $root = $ENV{"main"};
+my $out = $ENV{"out"};
+
+open OUT, ">$out" or die "$!";
+print OUT "[\n";
+
+open IN, "<$root" or die "$!";
+while (<IN>) {
+    if (/^\#include\s+\"(.*)\"/) {
+        print OUT "\"$1\"\n";
+    }
+    if (/^\#include\s+\<(.*)\>/) {
+        print OUT "\"$1\"\n";
+    }
+}
+close IN;
+
+print OUT "]\n";
+close OUT;
--- a/make/lib/link.sh
+++ b/make/lib/link.sh
@@ -0,0 +1,21 @@
+. $stdenv/setup
+
+shopt -s nullglob
+
+objs=
+for i in $objects; do
+    obj=$(echo $i/*.o)
+    objs="$objs $obj"
+done
+
+libs=
+for i in $libraries; do
+    lib=$(echo $i/*.a; echo $i/*.so)
+    name=$(echo $(basename $lib) | sed -e 's/^lib//' -e 's/.a$//' -e 's/.so$//')
+    libs="$libs -L$(dirname $lib) -l$name" 
+done
+
+echo "linking object files into \`$programName'..."
+
+mkdir $out
+gcc -o $out/$programName $objs $libs
--- a/make/lib/make-library.sh
+++ b/make/lib/make-library.sh
@@ -0,0 +1,28 @@
+. $stdenv/setup
+
+objs=
+for i in $objects; do
+    obj=$(echo $i/*.o)
+    objs="$objs $obj"
+done
+
+echo "archiving object files into library \`$libraryName'..."
+
+ensureDir $out
+
+if test -z "$sharedLib"; then
+
+    outPath=$out/lib${libraryName}.a
+
+    ar crs $outPath $objs
+    ranlib $outPath
+
+else
+
+    outPath=$out/lib${libraryName}.so
+
+    gcc -shared -o $outPath $objs
+
+fi    
+
+    
--- a/mergeTrunkBackIn.sh
+++ b/mergeTrunkBackIn.sh
@@ -0,0 +1,36 @@
+svn merge -r 10855:10943 https://svn.cs.uu.nl:12443/repos/trace/nix/trunk
+
+#already done:
+# 8628 
+# 8632
+# 8634
+# 8636
+# 8655
+# 8691
+# 8698
+# 8711
+# 8864
+# 9063
+# 9105 
+# 9207
+# 9217
+# 9332
+# 9429
+# 9433
+# 9435
+# 9437
+# 9439
+# 9445
+# 9476
+# 9506
+# 9536
+# 9549
+# 9561
+# 9584
+# 9751
+# 10133
+# 10154
+# 10531
+# 10692
+# 10855
+# 10943
--- a/misc/emacs/Makefile.am
+++ b/misc/emacs/Makefile.am
@@ -2,4 +2,4 @@ EXTRA_DIST = nix-mode.el

 install-data-local:
 	$(INSTALL) -d $(DESTDIR)$(datadir)/emacs/site-lisp
-	$(INSTALL_DATA) nix-mode.el $(DESTDIR)$(datadir)/emacs/site-lisp
+	$(INSTALL_DATA) $(srcdir)/nix-mode.el $(DESTDIR)$(datadir)/emacs/site-lisp
--- a/Show More
+++ b/Show More