Switching from WEBrick to Thin

One great thing about Octopress is that you can always preview your site in your browser locally with the rake preview command. This is a great feature for fiddling with the design without making every change public.1

But ever since I updated to OS X 10.9 Mavericks, accessing localhost:4000 was not working in Safari. It would only throw a blank page and 404s for the .css and .html files.

The odd thing was, the local server was working in Chrome and Firefox. Only Safari failed to display anything. Googling the problem, I found this Issue on the Octopress GitHub page. The issue seemed to be a bug in the default WEBrick webserver that creates the local localhost:4000 adress. The suggested fix was to use another web server

I decided to try Thin as a WEBrick alternative. Installing Thin is really simple. Just add "thin" to the end of your gem file (the file literally named gem in your Octopress installation directory). You can do this elegantly via Terminal with this command:

cd /your/octopress/root/directory/
echo gem \"thin\" >> Gemfile

After that you have to tell the ruby bundler to push the newly added gem to the project. Trigger a refresh with:

bundle install

That did the trick for me. Previewing Octopress with rake preview now works in Safari. With Thin I also got rid of this annoying (but harmless) error message that was constantly cropping up in Terminal while using WEBrick:

WARN Could not determine content-length of response body.
Set content-length of the response or set Response#chunked = true

By the way: I made the process of previewing my blog very fast with an Automator workflow that runs rake preview and then launches Safari to the server adress with the following Applescript:

tell application "Terminal"
do script with command "cd your/octopress/directory/ && rake generate && rake preview"
end tell
tell application "Safari" to open location "localhost:4000"


  1. Something that I do much more than I would like to.