diff --git a/composer.json b/composer.json
index b6b5b12..1faf062 100644
--- a/composer.json
+++ b/composer.json
@@ -9,6 +9,6 @@
         }
     ],
     "require": {
-        "phpoffice/phpspreadsheet": "dev-master"
+        "phpoffice/phpspreadsheet": "~1.8"
     }
 }