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-rw-r--r--gnu/services/avahi.scm108
-rw-r--r--gnu/services/base.scm219
-rw-r--r--gnu/services/dbus.scm120
-rw-r--r--gnu/services/dmd.scm76
-rw-r--r--gnu/services/networking.scm58
-rw-r--r--gnu/services/xorg.scm118
6 files changed, 513 insertions, 186 deletions
diff --git a/gnu/services/avahi.scm b/gnu/services/avahi.scm
new file mode 100644
index 0000000000..4b52fd7840
--- /dev/null
+++ b/gnu/services/avahi.scm
@@ -0,0 +1,108 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix 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 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu services avahi)
+  #:use-module (gnu services)
+  #:use-module (gnu system shadow)
+  #:use-module (gnu packages avahi)
+  #:use-module (guix monads)
+  #:use-module (guix gexp)
+  #:export (avahi-service))
+
+;;; Commentary:
+;;;
+;;; This module provides service definitions for the Avahi
+;;; "zero-configuration" tool set.
+;;;
+;;; Code:
+
+(define* (configuration-file #:key host-name publish?
+                             ipv4? ipv6? wide-area? domains-to-browse)
+  "Return an avahi-daemon configuration file."
+  (define (bool value)
+    (if value "yes\n" "no\n"))
+
+  (text-file "avahi-daemon.conf"
+             (string-append
+              "[server]\n"
+              (if host-name
+                  (string-append "host-name=" host-name "\n")
+                  "")
+
+              "browse-domains=" (string-join domains-to-browse)
+              "\n"
+              "use-ipv4=" (bool ipv4?)
+              "use-ipv6=" (bool ipv6?)
+              "[wide-area]\n"
+              "enable-wide-area=" (bool wide-area?)
+              "[publish]\n"
+              "disable-publishing=" (bool (not publish?)))))
+
+(define* (avahi-service #:key (avahi avahi)
+                        host-name
+                        (publish? #t)
+                        (ipv4? #t) (ipv6? #t)
+                        wide-area?
+                        (domains-to-browse '()))
+  "Return a service that runs @command{avahi-daemon}, a system-wide
+mDNS/DNS-SD responder that allows for service discovery and
+\"zero-configuration\" host name lookups.
+
+If @var{host-name} is different from @code{#f}, use that as the host name to
+publish for this machine; otherwise, use the machine's actual host name.
+
+When @var{publish?} is true, publishing of host names and services is allowed;
+in particular, avahi-daemon will publish the machine's host name and IP
+address via mDNS on the local network.
+
+When @var{wide-area?} is true, DNS-SD over unicast DNS is enabled.
+
+Boolean values @var{ipv4?} and @var{ipv6?} determine whether to use IPv4/IPv6
+sockets."
+  (mlet %store-monad ((config (configuration-file #:host-name host-name
+                                                  #:publish? publish?
+                                                  #:ipv4? ipv4?
+                                                  #:ipv6? ipv6?
+                                                  #:wide-area? wide-area?
+                                                  #:domains-to-browse
+                                                  domains-to-browse)))
+    (return
+     (service
+      (documentation "Run the Avahi mDNS/DNS-SD responder.")
+      (provision '(avahi-daemon))
+      (requirement '(dbus-system networking))
+
+      (start #~(make-forkexec-constructor
+                (string-append #$avahi "/sbin/avahi-daemon")
+                "--syslog" "-f" #$config))
+      (stop #~(make-kill-destructor))
+      (activate #~(begin
+                    (use-modules (guix build utils))
+                    (mkdir-p "/var/run/avahi-daemon")))
+
+      (user-groups (list (user-group
+                          (name "avahi"))))
+      (user-accounts (list (user-account
+                            (name "avahi")
+                            (group "avahi")
+                            (comment "Avahi daemon user")
+                            (home-directory "/var/empty")
+                            (shell
+                             "/run/current-system/profile/sbin/nologin"))))))))
+
+;;; avahi.scm ends here
diff --git a/gnu/services/base.scm b/gnu/services/base.scm
index d6c1707c6a..dc0161408b 100644
--- a/gnu/services/base.scm
+++ b/gnu/services/base.scm
@@ -24,11 +24,15 @@
   #:use-module ((gnu packages base)
                 #:select (glibc-final))
   #:use-module (gnu packages package-management)
+  #:use-module (guix gexp)
   #:use-module (guix monads)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-26)
   #:use-module (ice-9 format)
-  #:export (host-name-service
+  #:export (root-file-system-service
+            file-system-service
+            user-processes-service
+            host-name-service
             mingetty-service
             nscd-service
             syslog-service
@@ -42,14 +46,148 @@
 ;;;
 ;;; Code:
 
+(define (root-file-system-service)
+  "Return a service whose sole purpose is to re-mount read-only the root file
+system upon shutdown (aka. cleanly \"umounting\" root.)
+
+This service must be the root of the service dependency graph so that its
+'stop' action is invoked when dmd is the only process left."
+  (with-monad %store-monad
+    (return
+     (service
+      (documentation "Take care of the root file system.")
+      (provision '(root-file-system))
+      (start #~(const #t))
+      (stop #~(lambda _
+                ;; Return #f if successfully stopped.
+                (sync)
+
+                (call-with-blocked-asyncs
+                 (lambda ()
+                   (let ((null (%make-void-port "w")))
+                     ;; Close 'dmd.log'.
+                     (display "closing log\n")
+                     ;; XXX: Ideally we'd use 'stop-logging', but that one
+                     ;; doesn't actually close the port as of dmd 0.1.
+                     (close-port (@@ (dmd comm) log-output-port))
+                     (set! (@@ (dmd comm) log-output-port) null)
+
+                     ;; Redirect the default output ports..
+                     (set-current-output-port null)
+                     (set-current-error-port null)
+
+                     ;; Close /dev/console.
+                     (for-each close-fdes '(0 1 2))
+
+                     ;; At this point, there are no open files left, so the
+                     ;; root file system can be re-mounted read-only.
+                     (mount #f "/" #f
+                            (logior MS_REMOUNT MS_RDONLY)
+                            #:update-mtab? #f)
+
+                     #f)))))
+      (respawn? #f)))))
+
+(define* (file-system-service device target type
+                              #:key (check? #t) options)
+  "Return a service that mounts DEVICE on TARGET as a file system TYPE with
+OPTIONS.  When CHECK? is true, check the file system before mounting it."
+  (with-monad %store-monad
+    (return
+     (service
+      (provision (list (symbol-append 'file-system- (string->symbol target))))
+      (requirement '(root-file-system))
+      (documentation "Check, mount, and unmount the given file system.")
+      (start #~(lambda args
+                 #$(if check?
+                       #~(check-file-system #$device #$type)
+                       #~#t)
+                 (mount #$device #$target #$type 0 #$options)
+                 #t))
+      (stop #~(lambda args
+                ;; Normally there are no processes left at this point, so
+                ;; TARGET can be safely unmounted.
+                (umount #$target)
+                #f))))))
+
+(define %do-not-kill-file
+  ;; Name of the file listing PIDs of processes that must survive when halting
+  ;; the system.  Typical example is user-space file systems.
+  "/etc/dmd/do-not-kill")
+
+(define* (user-processes-service requirements #:key (grace-delay 2))
+  "Return the service that is responsible for terminating all the processes so
+that the root file system can be re-mounted read-only, just before
+rebooting/halting.  Processes still running GRACE-DELAY seconds after SIGTERM
+has been sent are terminated with SIGKILL.
+
+The returned service will depend on 'root-file-system' and on all the services
+listed in REQUIREMENTS.
+
+All the services that spawn processes must depend on this one so that they are
+stopped before 'kill' is called."
+  (with-monad %store-monad
+    (return (service
+             (documentation "When stopped, terminate all user processes.")
+             (provision '(user-processes))
+             (requirement (cons 'root-file-system requirements))
+             (start #~(const #t))
+             (stop #~(lambda _
+                       (define (kill-except omit signal)
+                         ;; Kill all the processes with SIGNAL except those
+                         ;; listed in OMIT and the current process.
+                         (let ((omit (cons (getpid) omit)))
+                           (for-each (lambda (pid)
+                                       (unless (memv pid omit)
+                                         (false-if-exception
+                                          (kill pid signal))))
+                                     (processes))))
+
+                       (define omitted-pids
+                         ;; List of PIDs that must not be killed.
+                         (if (file-exists? #$%do-not-kill-file)
+                             (map string->number
+                                  (call-with-input-file #$%do-not-kill-file
+                                    (compose string-tokenize
+                                             (@ (ice-9 rdelim) read-string))))
+                             '()))
+
+                       ;; When this happens, all the processes have been
+                       ;; killed, including 'deco', so DMD-OUTPUT-PORT and
+                       ;; thus CURRENT-OUTPUT-PORT are dangling.
+                       (call-with-output-file "/dev/console"
+                         (lambda (port)
+                           (display "sending all processes the TERM signal\n"
+                                    port)))
+
+                       (if (null? omitted-pids)
+                           (begin
+                             ;; Easy: terminate all of them.
+                             (kill -1 SIGTERM)
+                             (sleep #$grace-delay)
+                             (kill -1 SIGKILL))
+                           (begin
+                             ;; Kill them all except OMITTED-PIDS.  XXX: We
+                             ;; would like to (kill -1 SIGSTOP) to get a fixed
+                             ;; list of processes, like 'killall5' does, but
+                             ;; that seems unreliable.
+                             (kill-except omitted-pids SIGTERM)
+                             (sleep #$grace-delay)
+                             (kill-except omitted-pids SIGKILL)
+                             (delete-file #$%do-not-kill-file)))
+
+                       (display "all processes have been terminated\n")
+                       #f))
+             (respawn? #f)))))
+
 (define (host-name-service name)
   "Return a service that sets the host name to NAME."
   (with-monad %store-monad
     (return (service
              (documentation "Initialize the machine's host name.")
              (provision '(host-name))
-             (start `(lambda _
-                       (sethostname ,name)))
+             (start #~(lambda _
+                        (sethostname #$name)))
              (respawn? #f)))))
 
 (define* (mingetty-service tty
@@ -57,8 +195,7 @@
                            (motd (text-file "motd" "Welcome.\n"))
                            (allow-empty-passwords? #t))
   "Return a service to run mingetty on TTY."
-  (mlet %store-monad ((mingetty-bin (package-file mingetty "sbin/mingetty"))
-                      (motd         motd))
+  (mlet %store-monad ((motd motd))
     (return
      (service
       (documentation (string-append "Run mingetty on " tty "."))
@@ -66,12 +203,12 @@
 
       ;; Since the login prompt shows the host name, wait for the 'host-name'
       ;; service to be done.
-      (requirement '(host-name))
+      (requirement '(user-processes host-name))
 
-      (start  `(make-forkexec-constructor ,mingetty-bin "--noclear" ,tty))
-      (stop   `(make-kill-destructor))
-      (inputs `(("mingetty" ,mingetty)
-                ("motd" ,motd)))
+      (start  #~(make-forkexec-constructor
+                 (string-append #$mingetty "/sbin/mingetty")
+                 "--noclear" #$tty))
+      (stop   #~(make-kill-destructor))
 
       (pam-services
        ;; Let 'login' be known to PAM.  All the mingetty services will have
@@ -83,16 +220,23 @@
 
 (define* (nscd-service #:key (glibc glibc-final))
   "Return a service that runs libc's name service cache daemon (nscd)."
-  (mlet %store-monad ((nscd (package-file glibc "sbin/nscd")))
+  (with-monad %store-monad
     (return (service
              (documentation "Run libc's name service cache daemon (nscd).")
              (provision '(nscd))
-             (start `(make-forkexec-constructor ,nscd "-f" "/dev/null"
-                                                "--foreground"))
-             (stop  `(make-kill-destructor))
+             (requirement '(user-processes))
 
-             (respawn? #f)
-             (inputs `(("glibc" ,glibc)))))))
+             (activate #~(begin
+                           (use-modules (guix build utils))
+                           (mkdir-p "/var/run/nscd")))
+
+             (start
+              #~(make-forkexec-constructor (string-append #$glibc "/sbin/nscd")
+                                           "-f" "/dev/null"
+                                           "--foreground"))
+             (stop #~(make-kill-destructor))
+
+             (respawn? #f)))))
 
 (define (syslog-service)
   "Return a service that runs 'syslogd' with reasonable default settings."
@@ -120,21 +264,22 @@
 ")
 
   (mlet %store-monad
-      ((syslog.conf (text-file "syslog.conf" contents))
-       (syslogd     (package-file inetutils "libexec/syslogd")))
+      ((syslog.conf (text-file "syslog.conf" contents)))
     (return
      (service
       (documentation "Run the syslog daemon (syslogd).")
       (provision '(syslogd))
-      (start `(make-forkexec-constructor ,syslogd "--no-detach"
-                                         "--rcfile" ,syslog.conf))
-      (stop  `(make-kill-destructor))
-      (inputs `(("inetutils" ,inetutils)
-                ("syslog.conf" ,syslog.conf)))))))
+      (requirement '(user-processes))
+      (start
+       #~(make-forkexec-constructor (string-append #$inetutils
+                                                   "/libexec/syslogd")
+                                    "--no-detach"
+                                    "--rcfile" #$syslog.conf))
+      (stop #~(make-kill-destructor))))))
 
 (define* (guix-build-accounts count #:key
+                              (group "guixbuild")
                               (first-uid 30001)
-                              (gid 30000)
                               (shadow shadow))
   "Return a list of COUNT user accounts for Guix build users, with UIDs
 starting at FIRST-UID, and under GID."
@@ -143,34 +288,32 @@ starting at FIRST-UID, and under GID."
                     (lambda (n)
                       (user-account
                        (name (format #f "guixbuilder~2,'0d" n))
-                       (password "!")
                        (uid (+ first-uid n -1))
-                       (gid gid)
+                       (group group)
                        (comment (format #f "Guix Build User ~2d" n))
                        (home-directory "/var/empty")
-                       (shell (package-file shadow "sbin/nologin"))
-                       (inputs `(("shadow" ,shadow)))))
+                       (shell #~(string-append #$shadow "/sbin/nologin"))))
                     1+
                     1))))
 
 (define* (guix-service #:key (guix guix) (builder-group "guixbuild")
-                       (build-user-gid 30000) (build-accounts 10))
+                       (build-accounts 10))
   "Return a service that runs the build daemon from GUIX, and has
 BUILD-ACCOUNTS user accounts available under BUILD-USER-GID."
-  (mlet %store-monad ((daemon   (package-file guix "bin/guix-daemon"))
-                      (accounts (guix-build-accounts build-accounts
-                                                     #:gid build-user-gid)))
+  (mlet %store-monad ((accounts (guix-build-accounts build-accounts
+                                                     #:group builder-group)))
     (return (service
              (provision '(guix-daemon))
-             (start `(make-forkexec-constructor ,daemon
-                                                "--build-users-group"
-                                                ,builder-group))
-             (stop  `(make-kill-destructor))
-             (inputs `(("guix" ,guix)))
+             (requirement '(user-processes))
+             (start
+              #~(make-forkexec-constructor (string-append #$guix
+                                                          "/bin/guix-daemon")
+                                           "--build-users-group"
+                                           #$builder-group))
+             (stop #~(make-kill-destructor))
              (user-accounts accounts)
              (user-groups (list (user-group
                                  (name builder-group)
-                                 (id build-user-gid)
                                  (members (map user-account-name
                                                user-accounts)))))))))
 
diff --git a/gnu/services/dbus.scm b/gnu/services/dbus.scm
new file mode 100644
index 0000000000..3fbbfde09b
--- /dev/null
+++ b/gnu/services/dbus.scm
@@ -0,0 +1,120 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix 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 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu services dbus)
+  #:use-module (gnu services)
+  #:use-module (gnu system shadow)
+  #:use-module (gnu packages glib)
+  #:use-module (guix monads)
+  #:use-module (guix gexp)
+  #:export (dbus-service))
+
+;;; Commentary:
+;;;
+;;; This module supports the configuration of the D-Bus message bus
+;;; (http://dbus.freedesktop.org/).  D-Bus is an inter-process communication
+;;; facility.  Its "system bus" is used to allow system services to
+;;; communicate and be notified of system-wide events.
+;;;
+;;; Code:
+
+(define (dbus-configuration-directory dbus services)
+  "Return a configuration directory for @var{dbus} that includes the
+@code{etc/dbus-1/system.d} directories of each package listed in
+@var{services}."
+  (define build
+    #~(begin
+        (use-modules (sxml simple))
+
+        (define (services->sxml services)
+          ;; Return the SXML 'includedir' clauses for DIRS.
+          `(busconfig
+            ,@(map (lambda (dir)
+                     `(includedir ,(string-append dir
+                                                  "/etc/dbus-1/system.d")))
+                   services)))
+
+        (mkdir #$output)
+        (copy-file (string-append #$dbus "/etc/dbus-1/system.conf")
+                   (string-append #$output "/system.conf"))
+
+        ;; The default 'system.conf' has an <includedir> clause for
+        ;; 'system.d', so create it.
+        (mkdir (string-append #$output "/system.d"))
+
+        ;; 'system-local.conf' is automatically included by the default
+        ;; 'system.conf', so this is where we stuff our own things.
+        (call-with-output-file (string-append #$output "/system-local.conf")
+          (lambda (port)
+            (sxml->xml (services->sxml (list #$@services))
+                       port)))))
+
+  (gexp->derivation "dbus-configuration" build))
+
+(define* (dbus-service services #:key (dbus dbus))
+  "Return a service that runs the system bus, using @var{dbus}, with support
+for @var{services}.
+
+@var{services} must be a list of packages that provide an
+@file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
+and policy files.  For example, to allow avahi-daemon to use the system bus,
+@var{services} must be equal to @code{(list avahi)}."
+  (mlet %store-monad ((conf (dbus-configuration-directory dbus services)))
+    (return
+     (service
+      (documentation "Run the D-Bus system daemon.")
+      (provision '(dbus-system))
+      (requirement '(user-processes))
+      (start #~(make-forkexec-constructor
+                (string-append #$dbus "/bin/dbus-daemon")
+                "--nofork"
+                (string-append "--config-file=" #$conf "/system.conf")))
+      (stop #~(make-kill-destructor))
+      (user-groups (list (user-group
+                          (name "messagebus"))))
+      (user-accounts (list (user-account
+                            (name "messagebus")
+                            (group "messagebus")
+                            (comment "D-Bus system bus user")
+                            (home-directory "/var/run/dbus")
+                            (shell
+                             "/run/current-system/profile/sbin/nologin"))))
+      (activate #~(begin
+                    (use-modules (guix build utils))
+
+                    (mkdir-p "/var/run/dbus")
+
+                    (let ((user (getpwnam "messagebus")))
+                      (chown "/var/run/dbus"
+                             (passwd:uid user) (passwd:gid user)))
+
+                    (unless (file-exists? "/etc/machine-id")
+                      (format #t "creating /etc/machine-id...~%")
+                      (let ((prog (string-append #$dbus "/bin/dbus-uuidgen")))
+                        ;; XXX: We can't use 'system' because the initrd's
+                        ;; guile system(3) only works when 'sh' is in $PATH.
+                        (let ((pid (primitive-fork)))
+                          (if (zero? pid)
+                              (call-with-output-file "/etc/machine-id"
+                                (lambda (port)
+                                  (close-fdes 1)
+                                  (dup2 (port->fdes port) 1)
+                                  (execl prog)))
+                              (waitpid pid)))))))))))
+
+;;; dbus.scm ends here
diff --git a/gnu/services/dmd.scm b/gnu/services/dmd.scm
index 54fb5cbfd6..982c196fe4 100644
--- a/gnu/services/dmd.scm
+++ b/gnu/services/dmd.scm
@@ -17,6 +17,7 @@
 ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gnu services dmd)
+  #:use-module (guix gexp)
   #:use-module (guix monads)
   #:use-module (gnu services)
   #:use-module (ice-9 match)
@@ -29,52 +30,45 @@
 ;;;
 ;;; Code:
 
-(define (dmd-configuration-file services etc)
-  "Return the dmd configuration file for SERVICES, that initializes /etc from
-ETC (the name of a directory in the store) on startup."
-  (define config
-    `(begin
-       (use-modules (ice-9 ftw))
+(define (dmd-configuration-file services)
+  "Return the dmd configuration file for SERVICES."
+  (define modules
+    ;; Extra modules visible to dmd.conf.
+    '((guix build syscalls)
+      (guix build linux-initrd)
+      (guix build utils)))
 
-       (register-services
-        ,@(map (lambda (service)
-                `(make <service>
-                   #:docstring ',(service-documentation service)
-                   #:provides ',(service-provision service)
-                   #:requires ',(service-requirement service)
-                   #:respawn? ',(service-respawn? service)
-                   #:start ,(service-start service)
-                   #:stop ,(service-stop service)))
-               services))
+  (mlet %store-monad ((modules  (imported-modules modules))
+                      (compiled (compiled-modules modules)))
+    (define config
+      #~(begin
+          (eval-when (expand load eval)
+            (set! %load-path (cons #$modules %load-path))
+            (set! %load-compiled-path
+                  (cons #$compiled %load-compiled-path)))
 
-       ;; /etc is a mixture of static and dynamic settings.  Here is where we
-       ;; initialize it from the static part.
-       (format #t "populating /etc from ~a...~%" ,etc)
-       (let ((rm-f (lambda (f)
-                     (false-if-exception (delete-file f)))))
-         (rm-f "/etc/static")
-         (symlink ,etc "/etc/static")
-         (for-each (lambda (file)
-                     ;; TODO: Handle 'shadow' specially so that changed
-                     ;; password aren't lost.
-                     (let ((target (string-append "/etc/" file))
-                           (source (string-append "/etc/static/" file)))
-                       (rm-f target)
-                       (symlink source target)))
-                   (scandir ,etc
-                            (lambda (file)
-                              (not (member file '("." ".."))))))
+          (use-modules (ice-9 ftw)
+                       (guix build syscalls)
+                       ((guix build linux-initrd)
+                        #:select (check-file-system)))
 
-         ;; Prevent ETC from being GC'd.
-         (rm-f "/var/guix/gcroots/etc-directory")
-         (symlink ,etc "/var/guix/gcroots/etc-directory"))
+          (register-services
+           #$@(map (lambda (service)
+                     #~(make <service>
+                         #:docstring '#$(service-documentation service)
+                         #:provides '#$(service-provision service)
+                         #:requires '#$(service-requirement service)
+                         #:respawn? '#$(service-respawn? service)
+                         #:start #$(service-start service)
+                         #:stop #$(service-stop service)))
+                   services))
 
-       ;; guix-daemon 0.6 aborts if 'PATH' is undefined, so work around it.
-       (setenv "PATH" "/run/current-system/bin")
+          ;; guix-daemon 0.6 aborts if 'PATH' is undefined, so work around it.
+          (setenv "PATH" "/run/current-system/profile/bin")
 
-       (format #t "starting services...~%")
-       (for-each start ',(append-map service-provision services))))
+          (format #t "starting services...~%")
+          (for-each start '#$(append-map service-provision services))))
 
-  (text-file "dmd.conf" (object->string config)))
+    (gexp->file "dmd.conf" config)))
 
 ;;; dmd.scm ends here
diff --git a/gnu/services/networking.scm b/gnu/services/networking.scm
index 317800db50..8bb05850e3 100644
--- a/gnu/services/networking.scm
+++ b/gnu/services/networking.scm
@@ -20,6 +20,7 @@
   #:use-module (gnu services)
   #:use-module (gnu packages admin)
   #:use-module (gnu packages linux)
+  #:use-module (guix gexp)
   #:use-module (guix monads)
   #:export (static-networking-service))
 
@@ -41,40 +42,41 @@ true, it must be a string specifying the default network gateway."
   ;; TODO: Eventually we should do this using Guile's networking procedures,
   ;; like 'configure-qemu-networking' does, but the patch that does this is
   ;; not yet in stock Guile.
-  (mlet %store-monad ((ifconfig (package-file inetutils "bin/ifconfig"))
-                      (route    (package-file net-tools "sbin/route")))
+  (with-monad %store-monad
     (return
      (service
       (documentation
        (string-append "Set up networking on the '" interface
                       "' interface using a static IP address."))
       (provision '(networking))
-      (start `(lambda _
-                ;; Return #t if successfully started.
-                (and (zero? (system* ,ifconfig ,interface ,ip "up"))
-                     ,(if gateway
-                          `(zero? (system* ,route "add" "-net" "default"
-                                           "gw" ,gateway))
-                          #t)
-                     ,(if (pair? name-servers)
-                          `(call-with-output-file "/etc/resolv.conf"
-                             (lambda (port)
-                               (display
-                                "# Generated by 'static-networking-service'.\n"
-                                port)
-                               (for-each (lambda (server)
-                                           (format port "nameserver ~a~%"
-                                                   server))
-                                         ',name-servers)))
-                          #t))))
-      (stop  `(lambda _
+      (start #~(lambda _
+                 ;; Return #t if successfully started.
+                 (and (zero? (system* (string-append #$inetutils
+                                                     "/bin/ifconfig")
+                                      #$interface #$ip "up"))
+                      #$(if gateway
+                            #~(zero? (system* (string-append #$net-tools
+                                                             "/sbin/route")
+                                              "add" "-net" "default"
+                                              "gw" #$gateway))
+                            #t)
+                      #$(if (pair? name-servers)
+                            #~(call-with-output-file "/etc/resolv.conf"
+                                (lambda (port)
+                                  (display
+                                   "# Generated by 'static-networking-service'.\n"
+                                   port)
+                                  (for-each (lambda (server)
+                                              (format port "nameserver ~a~%"
+                                                      server))
+                                            '#$name-servers)))
+                            #t))))
+      (stop #~(lambda _
                 ;; Return #f is successfully stopped.
-                (not (and (system* ,ifconfig ,interface "down")
-                          (system* ,route "del" "-net" "default")))))
-      (respawn? #f)
-      (inputs `(("inetutils" ,inetutils)
-                ,@(if gateway
-                      `(("net-tools" ,net-tools))
-                      '())))))))
+                (not (and (system* (string-append #$inetutils "/bin/ifconfig")
+                                   #$interface "down")
+                          (system* (string-append #$net-tools "/sbin/route")
+                                   "del" "-net" "default")))))
+      (respawn? #f)))))
 
 ;;; networking.scm ends here
diff --git a/gnu/services/xorg.scm b/gnu/services/xorg.scm
index 086150a658..7215297f69 100644
--- a/gnu/services/xorg.scm
+++ b/gnu/services/xorg.scm
@@ -27,6 +27,7 @@
   #:use-module (gnu packages gnustep)
   #:use-module (gnu packages admin)
   #:use-module (gnu packages bash)
+  #:use-module (guix gexp)
   #:use-module (guix monads)
   #:use-module (guix derivations)
   #:export (xorg-start-command
@@ -86,77 +87,42 @@ Section \"Screen\"
   Device \"Device-vesa\"
 EndSection"))
 
-  (mlet %store-monad ((guile-bin   (package-file guile "bin/guile"))
-                      (xorg-bin    (package-file xorg-server "bin/X"))
-                      (dri         (package-file mesa "lib/dri"))
-                      (xkbcomp-bin (package-file xkbcomp "bin"))
-                      (xkb-dir     (package-file xkeyboard-config
-                                                 "share/X11/xkb"))
-                      (config      (xserver.conf)))
-    (define builder
+  (mlet %store-monad ((config (xserver.conf)))
+    (define script
       ;; Write a small wrapper around the X server.
-      `(let ((out (assoc-ref %outputs "out")))
-         (call-with-output-file out
-           (lambda (port)
-             (format port "#!~a --no-auto-compile~%!#~%" ,guile-bin)
-             (write '(begin
-                       (setenv "XORG_DRI_DRIVER_PATH" ,dri)
-                       (setenv "XKB_BINDIR" ,xkbcomp-bin)
-
-                       (apply execl
-
-                              ,xorg-bin "-ac" "-logverbose" "-verbose"
-                              "-xkbdir" ,xkb-dir
-                              "-config" ,(derivation->output-path config)
-                              "-nolisten" "tcp" "-terminate"
-
-                              ;; Note: SLiM and other display managers add the
-                              ;; '-auth' flag by themselves.
-                              (cdr (command-line))))
-                    port)))
-         (chmod out #o555)
-         #t))
-
-    (mlet %store-monad ((inputs (lower-inputs
-                                 `(("xorg" ,xorg-server)
-                                   ("xkbcomp" ,xkbcomp)
-                                   ("xkeyboard-config" ,xkeyboard-config)
-                                   ("mesa" ,mesa)
-                                   ("guile" ,guile)
-                                   ("xorg.conf" ,config)))))
-      (derivation-expression "start-xorg" builder
-                             #:inputs inputs))))
+      #~(begin
+          (setenv "XORG_DRI_DRIVER_PATH" (string-append #$mesa "/lib/dri"))
+          (setenv "XKB_BINDIR" (string-append #$xkbcomp "/bin"))
+
+          (apply execl (string-append #$xorg-server "/bin/X")
+                 "-ac" "-logverbose" "-verbose"
+                 "-xkbdir" (string-append #$xkeyboard-config "/share/X11/xkb")
+                 "-config" #$config
+                 "-nolisten" "tcp" "-terminate"
+
+                 ;; Note: SLiM and other display managers add the
+                 ;; '-auth' flag by themselves.
+                 (cdr (command-line)))))
+
+    (gexp->script "start-xorg" script)))
 
 (define* (xinitrc #:key
                   (guile guile-final)
                   (ratpoison ratpoison)
                   (windowmaker windowmaker))
   "Return a system-wide xinitrc script that starts the specified X session."
-  (mlet %store-monad ((guile-bin     (package-file guile "bin/guile"))
-                      (ratpoison-bin (package-file ratpoison "bin/ratpoison"))
-                      (wmaker-bin    (package-file windowmaker "bin/wmaker"))
-                      (inputs        (lower-inputs
-                                      `(("raptoison" ,ratpoison)
-                                        ("wmaker" ,windowmaker)))))
-    (define builder
-      `(let ((out (assoc-ref %outputs "out")))
-         (call-with-output-file out
-           (lambda (port)
-             (format port "#!~a --no-auto-compile~%!#~%" ,guile-bin)
-             (write '(begin
-                       (use-modules (ice-9 match))
-
-                       ;; TODO: Check for ~/.xsession.
-                       (match (command-line)
-                         ((_ "ratpoison")
-                          (execl ,ratpoison-bin))
-                         (_
-                          (execl ,wmaker-bin))))
-                    port)))
-         (chmod out #o555)
-         #t))
-
-    (derivation-expression "xinitrc" builder #:inputs inputs)))
+  (define builder
+    #~(begin
+        (use-modules (ice-9 match))
+
+        ;; TODO: Check for ~/.xsession.
+        (match (command-line)
+          ((_ "ratpoison")
+           (execl (string-append #$ratpoison "/bin/ratpoison")))
+          (_
+           (execl (string-append #$windowmaker "/bin/wmaker"))))))
+
+  (gexp->script "xinitrc" builder))
 
 (define* (slim-service #:key (slim slim)
                        (allow-empty-passwords? #t) auto-login?
@@ -173,7 +139,7 @@ When AUTO-LOGIN? is true, log in automatically as DEFAULT-USER."
     (mlet %store-monad ((startx  (or startx (xorg-start-command)))
                         (xinitrc (xinitrc)))
       (text-file* "slim.cfg"  "
-default_path /run/current-system/bin
+default_path /run/current-system/profile/bin
 default_xserver " startx "
 xserver_arguments :0 vt7
 xauth_path " xauth "/bin/xauth
@@ -181,7 +147,7 @@ authfile /var/run/slim.auth
 
 # The login command.  '%session' is replaced by the chosen session name, one
 # of the names specified in the 'sessions' setting: 'wmaker', 'xfce', etc.
-login_cmd  exec " xinitrc "%session
+login_cmd  exec " xinitrc " %session
 sessions   wmaker,ratpoison
 
 halt_cmd " dmd "/sbin/halt
@@ -190,25 +156,19 @@ reboot_cmd " dmd "/sbin/reboot
       (string-append "auto_login yes\ndefault_user " default-user)
       ""))))
 
-  (mlet %store-monad ((slim-bin (package-file slim "bin/slim"))
-                      (bash-bin (package-file bash "bin/bash"))
-                      (slim.cfg (slim.cfg)))
+  (mlet %store-monad ((slim.cfg (slim.cfg)))
     (return
      (service
       (documentation "Xorg display server")
       (provision '(xorg-server))
-      (requirement '(host-name))
+      (requirement '(user-processes host-name))
       (start
        ;; XXX: Work around the inability to specify env. vars. directly.
-       `(make-forkexec-constructor
-         ,bash-bin "-c"
-         ,(string-append "SLIM_CFGFILE=" (derivation->output-path slim.cfg)
-                         " " slim-bin
-                         " -nodaemon")))
-      (stop  `(make-kill-destructor))
-      (inputs `(("slim" ,slim)
-                ("slim.cfg" ,slim.cfg)
-                ("bash" ,bash)))
+       #~(make-forkexec-constructor
+          (string-append #$bash "/bin/sh") "-c"
+          (string-append "SLIM_CFGFILE=" #$slim.cfg
+                         " " #$slim "/bin/slim" " -nodaemon")))
+      (stop #~(make-kill-destructor))
       (respawn? #t)
       (pam-services
        ;; Tell PAM about 'slim'.