diff --git a/rails/README-content.md b/rails/README-content.md
index 004c216b..cdd65433 100644
--- a/rails/README-content.md
+++ b/rails/README-content.md
@@ -8,7 +8,7 @@ Ruby on Rails, often simply referred to as Rails, is an open source web applicat
 
 ## 1. create a `Dockerfile` in your rails app project
 
-    FROM rails
+    FROM rails:onbuild
 
 Put this file in the root of your app, next to the `Gemfile`.
 
diff --git a/rails/README.md b/rails/README.md
index be317eb0..4f2fa50c 100644
--- a/rails/README.md
+++ b/rails/README.md
@@ -8,7 +8,7 @@ Ruby on Rails, often simply referred to as Rails, is an open source web applicat
 
 ## 1. create a `Dockerfile` in your rails app project
 
-    FROM rails
+    FROM rails:onbuild
 
 Put this file in the root of your app, next to the `Gemfile`.