diff --git a/runcoms/zpreztorc b/runcoms/zpreztorc
index 209b704a..c57e09ff 100644
--- a/runcoms/zpreztorc
+++ b/runcoms/zpreztorc
@@ -95,7 +95,7 @@ zstyle ':prezto:module:prompt' theme 'smiley'
 #
 
 # Auto switch the Ruby version on directory change.
-# zstyle ':prezto:module:ruby:chruby' auto-switch 'yes'
+zstyle ':prezto:module:ruby:chruby' auto-switch 'yes'
 
 #
 # Screen