diff --git a/shell/main.sh b/shell/main.sh
index ff56a3c..f39c92b 100644
--- a/shell/main.sh
+++ b/shell/main.sh
@@ -1,3 +1,5 @@
+[ "${ENV}" ] || export ENV="/etc/shell/main.sh"
+
 main_env_root() {
 	dirname "${ENV}"
 }
@@ -40,5 +42,4 @@ main_import_modules() {
 	fi
 }
 
-# import modules
 main_import_modules "${ENV}"