diff --git a/README.md b/README.md
index b880045..03fa0f4 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ Dynamic DNS updates for UnitedDomains and Vodafone EasyBox
 
 ## Prerequisites
 ```
-apk add bash bind-tools wget curl libxml2-utils jq
+apk add bash grep bind-tools wget curl libxml2-utils jq
 ```