The setuid helper of D-Bus is responsible for "service activation".
It looks for '.service' files in fixed locations, but the default locations
make no sense (see below), so replace them with /etc/dbus-1/system-services.

--- dbus-1.10.0/dbus/dbus-sysdeps-util-unix.c	2015-10-22 00:07:03.829251854 +0200
+++ dbus-1.10.0/dbus/dbus-sysdeps-util-unix.c	2015-10-22 00:07:14.893445175 +0200
@@ -1410,10 +1410,7 @@ _dbus_get_standard_system_servicedirs (D
    * be available.
    */
   static const char standard_search_path[] =
-    "/usr/local/share:"
-    "/usr/share:"
-    DBUS_DATADIR ":"
-    "/lib";
+    "/etc";
   DBusString servicedir_path;
 
   _dbus_string_init_const (&servicedir_path, standard_search_path);
/><select name='h' onchange='this.form.submit();'>
<option value='koszko' selected='selected'>koszko</option>
<option value='koszko-scripts'>koszko-scripts</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>refs</a><a class='active' href='/guix/log/etc/snippets/scheme-mode/guix-cvs-reference'>log</a><a href='/guix/tree/etc/snippets/scheme-mode/guix-cvs-reference?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>tree</a><a href='/guix/commit/etc/snippets/scheme-mode/guix-cvs-reference?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>commit</a><a href='/guix/diff/etc/snippets/scheme-mode/guix-cvs-reference?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/etc/snippets/scheme-mode/guix-cvs-reference'>
<input type='hidden' name='id' value='ec0a2444176bef974809c15ad4c6acb7f5423ac1'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>root</a>/<a href='/guix/log/etc?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>etc</a>/<a href='/guix/log/etc/snippets?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>snippets</a>/<a href='/guix/log/etc/snippets/scheme-mode?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>scheme-mode</a>/<a href='/guix/log/etc/snippets/scheme-mode/guix-cvs-reference?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1'>guix-cvs-reference</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/etc/snippets/scheme-mode/guix-cvs-reference?id=ec0a2444176bef974809c15ad4c6acb7f5423ac1&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2017-12-15 23:15:32 +0100'>2017-12-15</span></td><td><a href='/guix/commit/etc/snippets/scheme-mode/guix-cvs-reference?id=42cdcdff1945b112452029c6a79445aac15ffd16'>etc: Add snippets.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/snippets/scheme-mode/guix-cvs-reference,
etc/snippets/scheme-mode/guix-git-reference,
etc/snippets/scheme-mode/guix-hg-reference,
etc/snippets/scheme-mode/guix-origin,
etc/snippets/scheme-mode/guix-package,
etc/snippets/scheme-mode/guix-svn-reference,
etc/snippets/text-mode/guix-commit-message-add-package,
etc/snippets/text-mode/guix-commit-message-update-package: New files.
* doc/contributing.texi (The Perfect Setup): Document snippets.
</span></span></td><td>Ricardo Wurmus</td></tr>