diff --git a/src/AttachableLogger.php b/src/AttachableLogger.php
index d7e6030..f201ea9 100644
--- a/src/AttachableLogger.php
+++ b/src/AttachableLogger.php
@@ -15,21 +15,24 @@
  * GNU General Public License for more details.
 */
 
+/**
+ * @phpstan-type LoggerAttachment \Closure(mixed $level, string $message) : void
+ */
 interface AttachableLogger extends \Logger{
 
 	/**
-	 * @param LoggerAttachment $attachment
+	 * @phpstan-param LoggerAttachment $attachment
 	 *
 	 * @return void
 	 */
-	public function addAttachment(\LoggerAttachment $attachment);
+	public function addAttachment(\Closure $attachment);
 
 	/**
-	 * @param LoggerAttachment $attachment
+	 * @phpstan-param LoggerAttachment $attachment
 	 *
 	 * @return void
 	 */
-	public function removeAttachment(\LoggerAttachment $attachment);
+	public function removeAttachment(\Closure $attachment);
 
 	/**
 	 * @return void
@@ -37,7 +40,8 @@ public function removeAttachment(\LoggerAttachment $attachment);
 	public function removeAttachments();
 
 	/**
-	 * @return \LoggerAttachment[]
+	 * @return \Closure[]
+	 * @phpstan-return LoggerAttachment[]
 	 */
 	public function getAttachments();
 }
diff --git a/src/LoggerAttachment.php b/src/LoggerAttachment.php
deleted file mode 100644
index b3332a0..0000000
--- a/src/LoggerAttachment.php
+++ /dev/null
@@ -1,28 +0,0 @@
-<?php
-
-/*
- * PocketMine Standard PHP Library
- * Copyright (C) 2014-2018 PocketMine Team <https://github.com/PocketMine/PocketMine-SPL>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
-*/
-
-interface LoggerAttachment{
-
-	/**
-	 * @param mixed  $level
-	 * @param string $message
-	 *
-	 * @return void
-	 */
-	public function log($level, $message);
-
-}