diff --git a/core/config.php b/core/config.php
index 85c3a2a1eb..341ed09a04 100644
--- a/core/config.php
+++ b/core/config.php
@@ -278,27 +278,27 @@ public function __construct(
         $this->table_name = $table_name;
         $this->sub_value = $sub_value;
         $this->sub_column = $sub_column;
-        $this->cache_name = empty($sub_value) ? "config" : "config_{$sub_value}";
+        $this->cache_name = empty($sub_value) ? "config" : "config_{$sub_column}={$sub_value}";
+        $this->values = cache_get_or_set($this->cache_name, fn () => $this->get_values());
+    }
 
-        $cached = $cache->get($this->cache_name);
-        if (!is_null($cached)) {
-            $this->values = $cached;
-        } else {
-            $this->values = [];
+    private function get_values(): mixed
+    {
+        $values = [];
 
-            $query = "SELECT name, value FROM {$this->table_name}";
-            $args = [];
+        $query = "SELECT name, value FROM {$this->table_name}";
+        $args = [];
 
-            if (!empty($sub_column) && !empty($sub_value)) {
-                $query .= " WHERE $sub_column = :sub_value";
-                $args["sub_value"] = $sub_value;
-            }
+        if (!empty($this->sub_column) && !empty($this->sub_value)) {
+            $query .= " WHERE {$this->sub_column} = :sub_value";
+            $args["sub_value"] = $this->sub_value;
+        }
 
-            foreach ($this->database->get_all($query, $args) as $row) {
-                $this->values[$row["name"]] = $row["value"];
-            }
-            $cache->set($this->cache_name, $this->values);
+        foreach ($this->database->get_all($query, $args) as $row) {
+            $values[$row["name"]] = $row["value"];
         }
+
+        return $values;
     }
 
     public function save(string $name = null): void
diff --git a/core/imageboard/search.php b/core/imageboard/search.php
index d6af5815eb..2b9dfff577 100644
--- a/core/imageboard/search.php
+++ b/core/imageboard/search.php
@@ -119,13 +119,8 @@ public static function count_tag(string $tag): int
 
     private static function count_total_images(): int
     {
-        global $cache, $database;
-        $total = $cache->get("image-count");
-        if (is_null($total)) {
-            $total = (int)$database->get_one("SELECT COUNT(*) FROM images");
-            $cache->set("image-count", $total, 600);
-        }
-        return $total;
+        global $database;
+        return cache_get_or_set("image-count", fn () => (int)$database->get_one("SELECT COUNT(*) FROM images"), 600);
     }
 
     /**
diff --git a/core/imageboard/tag.php b/core/imageboard/tag.php
index 547ed0f040..46bfc07071 100644
--- a/core/imageboard/tag.php
+++ b/core/imageboard/tag.php
@@ -55,9 +55,9 @@ public static function tags(string $search, int $limit = 10): array
             $cache_key .= "-" . $limit;
         }
 
-        $res = $cache->get($cache_key);
-        if (is_null($res)) {
-            $res = $database->get_pairs(
+        $res = cache_get_or_set(
+            $cache_key,
+            fn () => $database->get_pairs(
                 "
                 SELECT tag, count
                 FROM tags
@@ -68,9 +68,9 @@ public static function tags(string $search, int $limit = 10): array
                 $limitSQL
                 ",
                 $SQLarr
-            );
-            $cache->set($cache_key, $res, 600);
-        }
+            ),
+            600
+        );
 
         $counts = [];
         foreach ($res as $k => $v) {
diff --git a/core/polyfills.php b/core/polyfills.php
index bcecda02b8..6609945d8b 100644
--- a/core/polyfills.php
+++ b/core/polyfills.php
@@ -814,3 +814,18 @@ function stringer($s): string
     }
     return "<Unstringable>";
 }
+
+/**
+ * If a value is in the cache, return it; otherwise, call the callback
+ * to generate it and store it in the cache.
+ */
+function cache_get_or_set(string $key, callable $callback, int $ttl = 0)
+{
+    global $cache;
+    $value = $cache->get($key);
+    if ($value === null) {
+        $value = $callback();
+        $cache->set($key, $value, $ttl);
+    }
+    return $value;
+}
diff --git a/ext/autocomplete/main.php b/ext/autocomplete/main.php
index a350c00d96..147260e3d0 100644
--- a/ext/autocomplete/main.php
+++ b/ext/autocomplete/main.php
@@ -62,10 +62,8 @@ private function complete(string $search, int $limit): array
             $cache_key .= "-" . $limit;
         }
 
-        $res = $cache->get($cache_key);
-        if (is_null($res)) {
-            $res = $database->get_pairs(
-                "
+        return cache_get_or_set($cache_key, fn () => $database->get_pairs(
+            "
                 SELECT tag, count
                 FROM tags
                 WHERE LOWER(tag) LIKE LOWER(:search)
@@ -74,11 +72,7 @@ private function complete(string $search, int $limit): array
                 ORDER BY count DESC
                 $limitSQL
                 ",
-                $SQLarr
-            );
-            $cache->set($cache_key, $res, 600);
-        }
-
-        return $res;
+            $SQLarr
+        ), 600);
     }
 }
diff --git a/ext/blocks/main.php b/ext/blocks/main.php
index c7bcb2b969..2711fd9aba 100644
--- a/ext/blocks/main.php
+++ b/ext/blocks/main.php
@@ -53,11 +53,7 @@ public function onPageRequest(PageRequestEvent $event)
     {
         global $cache, $database, $page, $user;
 
-        $blocks = $cache->get("blocks");
-        if (is_null($blocks)) {
-            $blocks = $database->get_all("SELECT * FROM blocks");
-            $cache->set("blocks", $blocks, 600);
-        }
+        $blocks = cache_get_or_set("blocks", fn () => $database->get_all("SELECT * FROM blocks"), 600);
         foreach ($blocks as $block) {
             $path = implode("/", $event->args);
             if (strlen($path) < 4000 && fnmatch($block['pages'], $path)) {
diff --git a/ext/comment/main.php b/ext/comment/main.php
index a16d8d6435..8b5c4874ed 100644
--- a/ext/comment/main.php
+++ b/ext/comment/main.php
@@ -283,20 +283,17 @@ private function onPageRequest_list(PageRequestEvent $event)
     {
         global $cache, $config, $database, $user;
 
+        $threads_per_page = 10;
+
         $where = SPEED_HAX ? "WHERE posted > now() - interval '24 hours'" : "";
 
-        $total_pages = $cache->get("comment_pages");
-        if (is_null($total_pages)) {
-            $total_pages = (int)ceil($database->get_one("
-				SELECT COUNT(c1)
-				FROM (SELECT COUNT(image_id) AS c1 FROM comments $where GROUP BY image_id) AS s1
-			") / 10);
-            $cache->set("comment_pages", $total_pages, 600);
-        }
+        $total_pages = cache_get_or_set("comment_pages", fn () => (int)ceil($database->get_one("
+            SELECT COUNT(c1)
+            FROM (SELECT COUNT(image_id) AS c1 FROM comments $where GROUP BY image_id) AS s1
+        ") / $threads_per_page), 600);
         $total_pages = max($total_pages, 1);
 
         $current_page = $event->try_page_num(1, $total_pages);
-        $threads_per_page = 10;
         $start = $threads_per_page * $current_page;
 
         $result = $database->execute("
@@ -357,11 +354,7 @@ public function onPostListBuilding(PostListBuildingEvent $event)
         global $cache, $config;
         $cc = $config->get_int("comment_count");
         if ($cc > 0) {
-            $recent = $cache->get("recent_comments");
-            if (is_null($recent)) {
-                $recent = $this->get_recent_comments($cc);
-                $cache->set("recent_comments", $recent, 60);
-            }
+            $recent = cache_get_or_set("recent_comments", fn () => $this->get_recent_comments($cc), 60);
             if (count($recent) > 0) {
                 $this->theme->display_recent_comments($recent);
             }
diff --git a/ext/featured/main.php b/ext/featured/main.php
index 11cba6ecb0..de82bde3f4 100644
--- a/ext/featured/main.php
+++ b/ext/featured/main.php
@@ -52,14 +52,17 @@ public function onPostListBuilding(PostListBuildingEvent $event)
         global $cache, $config, $page, $user;
         $fid = $config->get_int("featured_id");
         if ($fid > 0) {
-            $image = $cache->get("featured_image_object:$fid");
-            if (is_null($image)) {
-                $image = Image::by_id($fid);
-                if ($image) { // make sure the object is fully populated before saving
-                    $image->get_tag_array();
-                }
-                $cache->set("featured_image_object:$fid", $image, 600);
-            }
+            $image = cache_get_or_set(
+                "featured_image_object:$fid",
+                function () use ($fid) {
+                    $image = Image::by_id($fid);
+                    if ($image) { // make sure the object is fully populated before saving
+                        $image->get_tag_array();
+                    }
+                    return $image;
+                },
+                600
+            );
             if (!is_null($image)) {
                 if (Extension::is_enabled(RatingsInfo::KEY)) {
                     if (!in_array($image->rating, Ratings::get_user_class_privs($user))) {
diff --git a/ext/index/main.php b/ext/index/main.php
index ea776f227c..9bfd6bfe9e 100644
--- a/ext/index/main.php
+++ b/ext/index/main.php
@@ -77,11 +77,11 @@ public function onPageRequest(PageRequestEvent $event)
                 if (SPEED_HAX) {
                     if ($count_search_terms === 0 && ($page_number < 10)) {
                         // extra caching for the first few post/list pages
-                        $images = $cache->get("post-list:$page_number");
-                        if (is_null($images)) {
-                            $images = Search::find_images(($page_number - 1) * $page_size, $page_size, $search_terms);
-                            $cache->set("post-list:$page_number", $images, 60);
-                        }
+                        $images = cache_get_or_set(
+                            "post-list:$page_number",
+                            fn () => Search::find_images(($page_number - 1) * $page_size, $page_size, $search_terms),
+                            60
+                        );
                     }
                 }
 
diff --git a/ext/pm/main.php b/ext/pm/main.php
index 5600a2d94b..6f56761bcd 100644
--- a/ext/pm/main.php
+++ b/ext/pm/main.php
@@ -297,18 +297,17 @@ public function onSendPM(SendPMEvent $event)
 
     private function count_pms(User $user)
     {
-        global $cache, $database;
+        global $database;
 
-        $count = $cache->get("pm-count:{$user->id}");
-        if (is_null($count)) {
-            $count = $database->get_one("
-					SELECT count(*)
-					FROM private_message
-					WHERE to_id = :to_id
-					AND is_read = :is_read
-			", ["to_id" => $user->id, "is_read" => false]);
-            $cache->set("pm-count:{$user->id}", $count, 600);
-        }
-        return $count;
+        return cache_get_or_set(
+            "pm-count:{$user->id}",
+            fn () => $database->get_one("
+                SELECT count(*)
+                FROM private_message
+                WHERE to_id = :to_id
+                AND is_read = :is_read
+            ", ["to_id" => $user->id, "is_read" => false]),
+            600
+        );
     }
 }
diff --git a/ext/report_image/main.php b/ext/report_image/main.php
index 2cc5b4be45..4a348a7f13 100644
--- a/ext/report_image/main.php
+++ b/ext/report_image/main.php
@@ -240,14 +240,12 @@ public function get_reported_images(): array
 
     public function count_reported_images(): int
     {
-        global $cache, $database;
-
-        $count = $cache->get("image-report-count");
-        if (is_null($count)) {
-            $count = $database->get_one("SELECT count(*) FROM image_reports");
-            $cache->set("image-report-count", $count, 600);
-        }
+        global $database;
 
-        return (int)$count;
+        return (int)cache_get_or_set(
+            "image-report-count",
+            fn () => $database->get_one("SELECT count(*) FROM image_reports"),
+            600
+        );
     }
 }
diff --git a/ext/tag_list/main.php b/ext/tag_list/main.php
index 3d13c7ae93..89d451389b 100644
--- a/ext/tag_list/main.php
+++ b/ext/tag_list/main.php
@@ -553,7 +553,6 @@ public static function get_related_tags(array $search, int $limit): array
     {
         global $cache, $database;
 
-
         $wild_tags = $search;
         $cache_key = "related_tags:" . md5(Tag::implode($search));
         $related_tags = $cache->get($cache_key);