diff --git a/manifests/extension.pp b/manifests/extension.pp
new file mode 100644
index 0000000..62264e7
--- /dev/null
+++ b/manifests/extension.pp
@@ -0,0 +1,43 @@
+define mediawiki::extension (
+  $type     = 'extension',
+  $ensure   = undef,
+  $source   = undef,
+  $revision = undef,
+) {
+  if $type != 'extension' and $type != 'skin' {
+    fail( '$type must be extension or skin' )
+  }
+
+  if $ensure == undef {
+    $vcsensure = $::lsbdistcodename ? {
+      'precise' => present,
+      'trusty'  => latest, # keep up to date
+    }
+  } else {
+    $vcsensure = $ensure
+  }
+  if $revision == undef {
+    $vcsrevision = $::lsbdistcodename ? {
+      'precise' => 'origin/master', # madness
+      'trusty'  => 'origin/REL1_27',
+    }
+  } else {
+    $vcsrevision = $revision
+  }
+  if $type == 'extension' {
+    $path = "extensions/${name}"
+  } elsif $type == 'skin' {
+    $path = "skins/${name}"
+  }
+  if $source == undef {
+    $vcssource = "https://gerrit.wikimedia.org/r/p/mediawiki/${path}.git"
+  } else {
+    $vcssource = $source
+  }
+  vcsrepo { "/srv/mediawiki/w/${path}":
+    ensure   => $vcsensure,
+    provider => git,
+    source   => $vcssource,
+    revision => $vcsrevision,
+  }
+}
diff --git a/manifests/init.pp b/manifests/init.pp
index e2c4a44..bc12c95 100644
--- a/manifests/init.pp
+++ b/manifests/init.pp
@@ -43,6 +43,52 @@ class mediawiki(
     include ::mediawiki::php
     include ::mediawiki::app
 
+    mediawiki::extension { [ 'ConfirmEdit',
+        'OpenID',
+        'Renameuser',
+        'WikiEditor',
+        'CodeEditor',
+        'Scribunto',
+        'Gadgets',
+        'CategoryTree',
+        'ParserFunctions',
+        'SyntaxHighlight_GeSHi',
+        'Cite',
+        'cldr',
+        'Babel',
+        'Translate',
+        'Collection',
+        'Nuke',
+        'AntiSpoof',
+        'Mantle',
+        'MobileFrontend',
+        'SubPageList3',
+        'ReplaceText',
+        'googleAnalytics',
+        'Echo',
+        'UniversalLanguageSelector',
+        'Elastica',
+        'CirrusSearch',
+        'SpamBlacklist',
+        'SmiteSpam' ]:
+    }
+
+    mediawiki::extension { 'EmbedVideo':
+        ensure   => present,
+        source   => 'https://github.com/HydraWiki/mediawiki-embedvideo.git',
+        revision => 'origin/master', # Not from Wikimedia repos :(
+    }
+    if $::lsbdistcodename == 'precise' {
+        # On trusty we use 1.27, which has this extension merged into core
+        # See https://phabricator.wikimedia.org/T108213
+        mediawiki::extension { 'OpenSearchXml': }
+    }
+
+    mediawiki::extension { 'strapping':
+        type   => 'skin',
+        source => 'https://gerrit.wikimedia.org/r/p/mediawiki/skins/mediawiki-strapping.git',
+    }
+
     file { '/srv/mediawiki/w/LocalSettings.php':
         ensure  => link,
         target  => '/srv/mediawiki/Settings.php',
diff --git a/templates/Settings.php.erb b/templates/Settings.php.erb
index 94a7125..cddf94f 100644
--- a/templates/Settings.php.erb
+++ b/templates/Settings.php.erb
@@ -278,8 +278,10 @@ include_once("$IP/extensions/Mantle/Mantle.php");
 require_once("$IP/extensions/MobileFrontend/MobileFrontend.php");
 $wgMFAutodetectMobileView = true;
 
-# Needed by MobileFrontend
-require_once( "$IP/extensions/OpenSearchXml/OpenSearchXml.php" );
+if ( file_exists( "$IP/extensions/OpenSearchXml" ) ) {
+	# Needed by MobileFrontend
+	require_once( "$IP/extensions/OpenSearchXml/OpenSearchXml.php" );
+}
 
 require_once( "$IP/extensions/SubPageList3/SubPageList3.php" );