diff --git a/inc/lock.php b/inc/lock.php
index 23c0bce4..5a83562a 100644
--- a/inc/lock.php
+++ b/inc/lock.php
@@ -1,43 +1,84 @@
 <?php
-class Lock {
-	function __construct($key) {
-		global $config;
-		if ($config['lock']['enabled'] == 'fs') {
-			$key = str_replace('/', '::', $key);
-			$key = str_replace("\0", '', $key);
 
-			$this->f = fopen("tmp/locks/$key", "w");
+class Locks {
+	private static function filesystem(string $key): Lock|false {
+		$key = str_replace('/', '::', $key);
+		$key = str_replace("\0", '', $key);
+
+		$fd = fopen("tmp/locks/$key", "w");
+		if ($fd === false) {
+			return false;
 		}
+
+		return new class($fd) implements Lock {
+			// Resources have no type in php.
+			private mixed $f;
+
+
+			function __construct($fd) {
+				$this->f = $fd;
+			}
+
+			public function get(bool $nonblock = false): Lock|false {
+				$wouldblock = false;
+				flock($this->f, LOCK_SH | ($nonblock ? LOCK_NB : 0), $wouldblock);
+				if ($nonblock && $wouldblock) {
+					return false;
+				}
+				return $this;
+			}
+
+			public function get_ex(bool $nonblock = false): Lock|false {
+				$wouldblock = false;
+				flock($this->f, LOCK_EX | ($nonblock ? LOCK_NB : 0), $wouldblock);
+				if ($nonblock && $wouldblock) {
+					return false;
+				}
+				return $this;
+			}
+
+			public function free(): Lock {
+				flock($this->f, LOCK_UN);
+				return $this;
+			}
+		};
 	}
 
-	// Get a shared lock
-	function get($nonblock = false) {
-		global $config;
-		if ($config['lock']['enabled'] == 'fs') {
-			$wouldblock = false;
-			flock($this->f, LOCK_SH | ($nonblock ? LOCK_NB : 0), $wouldblock);
-			if ($nonblock && $wouldblock) return false;
-		}
-		return $this;
+	/**
+	 * No-op. Can be used for mocking.
+	 */
+	public static function none(): Lock|false {
+		return new class() implements Lock {
+			public function get(bool $nonblock = false): Lock|false {
+				return $this;
+			}
+
+			public function get_ex(bool $nonblock = false): Lock|false {
+				return $this;
+			}
+
+			public function free(): Lock {
+				return $this;
+			}
+		};
 	}
 
-	// Get an exclusive lock
-	function get_ex($nonblock = false) {
-		global $config;
+	public static function get_lock(array $config, string $key): Lock|false {
 		if ($config['lock']['enabled'] == 'fs') {
-			$wouldblock = false;
-			flock($this->f, LOCK_EX | ($nonblock ? LOCK_NB : 0), $wouldblock);
-			if ($nonblock && $wouldblock) return false;
+			return self::filesystem($key);
+		} else {
+			return self::none();
 		}
-		return $this;
-	}
-
-	// Free a lock
-	function free() {
-		global $config;
-		if ($config['lock']['enabled'] == 'fs') {
-			flock($this->f, LOCK_UN);
-		}
-		return $this;
 	}
 }
+
+interface Lock {
+	// Get a shared lock
+	public function get(bool $nonblock = false): Lock|false;
+
+	// Get an exclusive lock
+	public function get_ex(bool $nonblock = false): Lock|false;
+
+	// Free a lock
+	public function free(): Lock;
+}
diff --git a/inc/queue.php b/inc/queue.php
index 66305b3b..a3873491 100644
--- a/inc/queue.php
+++ b/inc/queue.php
@@ -3,7 +3,7 @@
 class Queue {
   function __construct($key) { global $config;
     if ($config['queue']['enabled'] == 'fs') {
-      $this->lock = new Lock($key);
+      $this->lock = Locks::get_lock($config, $key);
       $key = str_replace('/', '::', $key);
       $key = str_replace("\0", '', $key);
       $this->key = "tmp/queue/$key/";