diff --git a/Dockerfile b/Dockerfile
index 66e2d0c..7aeb534 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -17,9 +17,11 @@ RUN \
 RUN \
   echo "**** install dev runtimes ****" && \
   curl -fsSL https://deb.nodesource.com/setup_lts.x | sudo -E bash - && \
-  apt-get update && \
+  # update already called by nodesource install script
+  # apt-get update && \
   apt-get install -y \
-    nodejs \
+    # let the user install nodejs to save 800MB in image
+    # nodejs \
     golang-go &&\
   echo "**** clean up ****" && \
   apt-get clean && \