diff --git a/README.md b/README.md
index e36c48d..ab3baa4 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,10 @@
 npm2tgz generates a Slackware compatible package from a node module
-  usage: npm2tgz <modules_name>
+  usage: <OPTIONS> npm2tgz <modules_name>
   The resulting package is located under /tmp
+  possible OPTIONS are:
+    BUILD=<value>  (currently: 1)
+    TAG=<value>    (currently: SBo)
+    OUTPUT=<value> (currently: /tmp)
+    ARCH=<value>   (currently: npmjs)
+    PREFIX=<value> (currently: /usr)
+    NPMBIN=<value> (currently: /usr/bin/npm)