diff --git a/classes/db/migrations.php b/classes/db/migrations.php
index 5f969c513..ffce2af5f 100644
--- a/classes/db/migrations.php
+++ b/classes/db/migrations.php
@@ -189,14 +189,11 @@ class Db_Migrations {
 			$filename = "{$this->base_path}/{$this->base_filename}";
 
 		if (file_exists($filename)) {
-			$lines =	array_filter(preg_split("/[\r\n]/", file_get_contents($filename)),
-							function ($line) {
-								return strlen(trim($line)) > 0 && strpos($line, "--") !== 0;
-							});
+			$lines = array_filter(preg_split("/[\r\n]/", file_get_contents($filename)),
+				fn($line) => strlen(trim($line)) > 0 && strpos($line, "--") !== 0);
 
-			return array_filter(explode(";", implode("", $lines)), function ($line) {
-				return strlen(trim($line)) > 0 && !in_array(strtolower($line), ["begin", "commit"]);
-			});
+			return array_filter(explode(";", implode("", $lines)),
+				fn($line) => strlen(trim($line)) > 0 && !in_array(strtolower($line), ["begin", "commit"]));
 
 		} else {
 			user_error("Requested schema file ${filename} not found.", E_USER_ERROR);
diff --git a/classes/digest.php b/classes/digest.php
index 15203166b..3e943e6dd 100644
--- a/classes/digest.php
+++ b/classes/digest.php
@@ -163,9 +163,7 @@ class Digest
 			$article_labels_formatted = "";
 
 			if (is_array($article_labels) && count($article_labels) > 0) {
-				$article_labels_formatted = implode(", ", array_map(function($a) {
-					return $a[1];
-				}, $article_labels));
+				$article_labels_formatted = implode(", ", array_map(fn($a) => $a[1], $article_labels));
 			}
 
 			$tpl->setVariable('FEED_TITLE', $line["feed_title"]);
diff --git a/classes/pref/prefs.php b/classes/pref/prefs.php
index 3e651297e..01b58005b 100644
--- a/classes/pref/prefs.php
+++ b/classes/pref/prefs.php
@@ -872,13 +872,13 @@ class Pref_Prefs extends Handler_Protected {
 							PluginHost::getInstance()->get_hooks(PluginHost::HOOK_FEED_PARSED),
 							PluginHost::getInstance()->get_hooks(PluginHost::HOOK_FETCH_FEED));
 
-						$feed_handlers = array_filter($feed_handlers, function($plugin) use ($feed_handler_whitelist) {
-							return in_array(get_class($plugin), $feed_handler_whitelist) === false; });
+						$feed_handlers = array_filter($feed_handlers,
+							fn($plugin) => in_array(get_class($plugin), $feed_handler_whitelist) === false);
 
 						if (count($feed_handlers) > 0) {
 							print_error(
 								T_sprintf("The following plugins use per-feed content hooks. This may cause excessive data usage and origin server load resulting in a ban of your instance: <b>%s</b>" ,
-									implode(", ", array_map(function($plugin) { return get_class($plugin); }, $feed_handlers))
+									implode(", ", array_map(fn($plugin) => get_class($plugin), $feed_handlers))
 								) . " (<a href='https://tt-rss.org/wiki/FeedHandlerPlugins' target='_blank'>".__("More info...")."</a>)"
 							);
 						}
@@ -1067,9 +1067,7 @@ class Pref_Prefs extends Handler_Protected {
 			}
 		}
 
-		$rv = array_values(array_filter($rv, function ($item) {
-			return $item["rv"]["need_update"];
-		}));
+		$rv = array_values(array_filter($rv, fn($item) => $item["rv"]["need_update"]));
 
 		return $rv;
 	}
diff --git a/classes/rssutils.php b/classes/rssutils.php
index e039284f2..e590f1665 100755
--- a/classes/rssutils.php
+++ b/classes/rssutils.php
@@ -39,7 +39,7 @@ class RSSUtils {
 
 		// check icon files once every Config::get(Config::CACHE_MAX_DAYS) days
 		$icon_files = array_filter(glob(Config::get(Config::ICONS_DIR) . "/*.ico"),
-			function($f) { return filemtime($f) < time() - 86400 * Config::get(Config::CACHE_MAX_DAYS); });
+			fn($f) => filemtime($f) < time() - 86400 * Config::get(Config::CACHE_MAX_DAYS));
 
 		foreach ($icon_files as $icon) {
 			$feed_id = basename($icon, ".ico");
@@ -865,7 +865,7 @@ class RSSUtils {
 				$pluginhost->run_hooks(PluginHost::HOOK_FILTER_TRIGGERED,
 					$feed, $feed_obj->owner_uid, $article, $matched_filters, $matched_rules, $article_filters);
 
-				$matched_filter_ids = array_map(function($f) { return $f['id']; }, $matched_filters);
+				$matched_filter_ids = array_map(fn($f) => $f['id'], $matched_filters);
 
 				if (count($matched_filter_ids) > 0) {
 					$filter_objs = ORM::for_table('ttrss_filters2')
@@ -1801,7 +1801,7 @@ class RSSUtils {
 			[$cat_id]);
 
 		$check_cats_str = join(",", $check_cats);
-		$check_cats_fullids = array_map(function($a) { return "CAT:$a"; }, $check_cats);
+		$check_cats_fullids = array_map(fn($a) => "CAT:$a", $check_cats);
 
 		while ($line = $sth->fetch()) {
 			$filter_id = $line["id"];