diff --git a/module/VuFind/src/VuFind/Bootstrap.php b/module/VuFind/src/VuFind/Bootstrap.php
index 981789e33fb6317f2ce9bbee86b7900ab4cd29e0..d2364aa2f3ee0fe782c86ae6a73c55634ef611e8 100644
--- a/module/VuFind/src/VuFind/Bootstrap.php
+++ b/module/VuFind/src/VuFind/Bootstrap.php
@@ -165,7 +165,7 @@ class Bootstrap
         if (isset($this->config->System->available)
             && !$this->config->System->available
         ) {
-            $callback = function($e) {
+            $callback = function ($e) {
                 $routeMatch = new RouteMatch(
                     array('controller' => 'Error', 'action' => 'Unavailable'), 1
                 );
@@ -200,7 +200,7 @@ class Bootstrap
      */
     protected function initContext()
     {
-        $callback = function($event) {
+        $callback = function ($event) {
             $serviceManager = $event->getApplication()->getServiceManager();
             $viewModel = $serviceManager->get('viewmanager')->getViewModel();
 
@@ -225,7 +225,7 @@ class Bootstrap
      */
     protected function initHeadTitle()
     {
-        $callback = function($event) {
+        $callback = function ($event) {
             $serviceManager = $event->getApplication()->getServiceManager();
             $renderer = $serviceManager->get('viewmanager')->getRenderer();
             $headTitle = $renderer->plugin('headtitle');
@@ -249,7 +249,7 @@ class Bootstrap
         }
 
         $config =& $this->config;
-        $callback = function($event) use ($config) {
+        $callback = function ($event) use ($config) {
             // Setup Translator
             $request = $event->getRequest();
             if (($language = $request->getPost()->get('mylang', false))
@@ -301,7 +301,7 @@ class Bootstrap
         // Attach remaining theme configuration to the dispatch event at high
         // priority (TODO: use priority constant once defined by framework):
         $config =& $this->config;
-        $callback = function($event) use ($config) {
+        $callback = function ($event) use ($config) {
             $theme = new ThemeInitializer($config, $event);
             $theme->init();
         };
@@ -316,7 +316,7 @@ class Bootstrap
      */
     protected function initExceptionBased404s()
     {
-        $callback = function($e) {
+        $callback = function ($e) {
             $exception = $e->getParam('exception');
             if (is_object($exception)) {
                 if ($exception instanceof \VuFind\Exception\RecordMissing) {
@@ -341,7 +341,7 @@ class Bootstrap
      */
     protected function initErrorLogging()
     {
-        $callback = function($event) {
+        $callback = function ($event) {
             $sm = $event->getApplication()->getServiceManager();
             if ($sm->has('Logger')) {
                 $log = $sm->get('Logger');
diff --git a/module/VuFind/src/VuFind/Controller/SearchController.php b/module/VuFind/src/VuFind/Controller/SearchController.php
index d1fbf1f169d314a74797d586c159d6f797de2b16..b9b12f422ac78fb9f7561e3dace017e72926ae92 100644
--- a/module/VuFind/src/VuFind/Controller/SearchController.php
+++ b/module/VuFind/src/VuFind/Controller/SearchController.php
@@ -451,7 +451,7 @@ class SearchController extends AbstractSearch
         $result = $this->reserves()->findReserves($course, $inst, $dept);
 
         // Build a list of unique IDs
-        $callback = function($i) {
+        $callback = function ($i) {
             return $i['BIB_ID'];
         };
         $bibIDs = array_unique(array_map($callback, $result));
diff --git a/module/VuFind/src/VuFind/Db/Table/Tags.php b/module/VuFind/src/VuFind/Db/Table/Tags.php
index 9e34b6e48bc085bf9353c9101e4aa22d6357868c..b586d44ae03abeda40277e8765efe8cc5331ffb8 100644
--- a/module/VuFind/src/VuFind/Db/Table/Tags.php
+++ b/module/VuFind/src/VuFind/Db/Table/Tags.php
@@ -157,7 +157,7 @@ class Tags extends Gateway
      */
     public function getTagList($sort, $limit = 100, $extra_where = null)
     {
-        $callback = function($select) use ($sort, $limit, $extra_where) {
+        $callback = function ($select) use ($sort, $limit, $extra_where) {
             $select->columns(
                 array(
                     'id', 'tag',
diff --git a/module/VuFind/src/VuFind/Db/Table/UserStats.php b/module/VuFind/src/VuFind/Db/Table/UserStats.php
index 6bfb97334e035c65731633598953972c6961eefc..6b64a7dced927895317ab6e64f9cfc5855dc1152 100644
--- a/module/VuFind/src/VuFind/Db/Table/UserStats.php
+++ b/module/VuFind/src/VuFind/Db/Table/UserStats.php
@@ -59,7 +59,7 @@ class UserStats extends Gateway
      */
     public function getBrowserStats($withVersions = false, $limit = 5)
     {
-        $callback = function($select) use ($withVersions, $limit) {
+        $callback = function ($select) use ($withVersions, $limit) {
             if ($withVersions) {
                 $select->columns(
                     array(
diff --git a/module/VuFind/src/VuFind/Db/Table/UserStatsFields.php b/module/VuFind/src/VuFind/Db/Table/UserStatsFields.php
index 5e15faee90b3bc6c07cf3dfe1a2e736f0b9276db..06365e77da3d8fc25d802cafd947e29fdc446baf 100644
--- a/module/VuFind/src/VuFind/Db/Table/UserStatsFields.php
+++ b/module/VuFind/src/VuFind/Db/Table/UserStatsFields.php
@@ -93,7 +93,7 @@ class UserStatsFields extends Gateway
         if (!is_array($fields)) {
             $fields = array($fields);
         }
-        $callback = function($select) use ($fields, $values) {
+        $callback = function ($select) use ($fields, $values) {
             $select->columns(
                 array($fields[0] => 'value')
             );
@@ -124,7 +124,7 @@ class UserStatsFields extends Gateway
      */
     public function getTop($field, $number)
     {
-        $callback = function($select) use ($field, $number) {
+        $callback = function ($select) use ($field, $number) {
             $select->columns(
                 array(
                     'value',
diff --git a/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php b/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php
index 08853d27c3c183fbe2ebb4dd21bc652b7918a6bb..9d11a3cb47ba92dcf9a565d708d6b4689933dde0 100644
--- a/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php
+++ b/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php
@@ -1014,7 +1014,7 @@ class SolrDefault extends AbstractBase
         // If non-empty, map internal URL array to expected return format;
         // otherwise, return empty array:
         if (isset($this->fields['url']) && is_array($this->fields['url'])) {
-            $filter = function($url) {
+            $filter = function ($url) {
                 return array('url' => $url);
             };
             return array_map($filter, $this->fields['url']);
diff --git a/module/VuFind/src/VuFind/Search/Solr/Params.php b/module/VuFind/src/VuFind/Search/Solr/Params.php
index e293535a9d38904b29b8933af7e084c9196cc83c..4f38ad1e6367ce6f2c7af11493fb58ae487095bb 100644
--- a/module/VuFind/src/VuFind/Search/Solr/Params.php
+++ b/module/VuFind/src/VuFind/Search/Solr/Params.php
@@ -433,7 +433,7 @@ class Params extends BaseParams
             return $this->setOverrideQuery('NOT *:*');
         }
 
-        $callback = function($i) {
+        $callback = function ($i) {
             return '"' . addcslashes($i, '"') . '"';
         };
         $ids = array_map($callback, $ids);