diff --git a/composer.json b/composer.json
index 795e404..46902cd 100644
--- a/composer.json
+++ b/composer.json
@@ -11,7 +11,7 @@
         }
     ],
     "require": {
-        "php": "^5.4 || ^7.0"
+        "php": "^5.5|^7.0"
     },
     "require-dev": {
         "php-http/httplug": "^1.0",