diff --git a/composer.json b/composer.json
index 2e0a940..ab5ba0c 100644
--- a/composer.json
+++ b/composer.json
@@ -19,6 +19,6 @@
   },
   "license": "GPL-2.0+",
   "require": {
-    "drupal/captcha": "dev"
+    "drupal/captcha": "8.1.x-dev"
   }
 }