diff --git a/xos/configurations/common/Makefile.cloudlab b/xos/configurations/common/Makefile.cloudlab
index 6efb13f..ddf9daf 100644
--- a/xos/configurations/common/Makefile.cloudlab
+++ b/xos/configurations/common/Makefile.cloudlab
@@ -17,4 +17,4 @@
 
 install_docker:
 	which docker > /dev/null || wget -qO- https://get.docker.com/ | sh
-	sudo usermod -aG docker $(whoami)
+	sudo usermod -aG docker $(shell whoami)