diff --git a/composer.json b/composer.json
index 394a2e6..2eb8eaf 100644
--- a/composer.json
+++ b/composer.json
@@ -29,7 +29,7 @@
         "bin-dir": "bin/"
     },
     "require": {
-        "php": ">= 5.6.0 || 7.0.0 - 7.0.4 || >= 7.0.6",
+        "php": ">= 5.5.9 || 7.0.0 - 7.0.4 || >= 7.0.6",
         "eugene-matvejev/compass": "^0.1",
         "leafo/lessphp": "^0.5"
     },