diff --git a/lib/php/libsdk/SDK/Cache.php b/lib/php/libsdk/SDK/Cache.php
index 84f9ad7..674ba1b 100644
--- a/lib/php/libsdk/SDK/Cache.php
+++ b/lib/php/libsdk/SDK/Cache.php
@@ -36,6 +36,7 @@ class Cache
 		return file_exists($this->getCacheablePath($path, $relative));
 	}/*}}}*/
 
+	/* TODO Sometimes a timestamp comparison might make sense. */
 	public function cachedContentDiffers(string $path, string $content, bool $relative = false) : bool
 	{/*{{{*/
 		$p = $this->getCacheablePath($path, $relative);