diff --git a/composer.json b/composer.json
index 32f92ad..d94ef1a 100644
--- a/composer.json
+++ b/composer.json
@@ -19,6 +19,7 @@
 	],
 	"require": {
 		"php": ">=5.3.0",
+		"ext-pcntl": "*",
 		"colinmollenhour/credis": "dev-master"
 	},
 	"suggest": {
@@ -36,4 +37,4 @@
 			"Resque": "lib"
 		}
 	}
-}
\ No newline at end of file
+}