Now that Apple has released their new OS, Snow Leopard, thousands of devoted Mac web developers are jumping on the upgrade bandwagon - and for good reason! Snow Leopard has implemented a ton of nice little tweaks to make your Mac faster and more reliable, resulting in a much smoother development environment.

One of the biggest changes in Snow Leopard is the shift to 64-bit computing. While this change will make for huge speed increases and optimized memory usage, it also means that you'll need to upgrade or re-compile any 32-bit applications or libraries still lingering around (that is, if you installed Snow Leopard on top of your existing system rather than doing a clean install).

So to make your lives easier, I've put together a list of all the steps that I had to take to get back down to business. These instructions should work for most Mac/Rails setups, though you may need to tweak certain steps or take a few more should errors arise.

1. Prep Your Mac & Install Snow Leopard

Lifehacker put together a pretty solid guide to cleaning up your OS X 10.5 Leopard installation, backing it up in case of errors, and finally installing Snow Leopard: Prep Your Mac for Snow Leopard. Installation took about an hour to complete on my MacBook Pro.

2. Upgrade Xcode with the Snow Leopard Optional Install

Don't pop that install disc out just yet, next we need to install the enhanced version of Xcode developer tools. The Xcode installer can be found in the Optional Installs folder and the default settings should do just fine.

3. Restore Apache configurations from your 10.5 Leopard backup

It's likely that your custom Apache configurations were wiped out during the upgrade, but luckily you read through Step 1 and have a nice lil' backup of your 10.5 install. I only needed to restore my Virtual Hosts file, but I've seen others report that they needed to restore httpd.conf, as well.

4. Upgrade to 64-bit MySQL

Hivelogic has come to the rescue and provided a great tutorial on Compiling MySQL for Snow Leopard. It worked great for me, however I had to run the gem install with a specified C extension to force 64-bit compilation:

5. Upgrade to 64-bit Ruby

Once again, Hivelogic comes through with their Compiling Ruby, RubyGems, and Rails on Snow Leopard tutorial.

6. Upgrade remaining 32-bit gems

The RidingRails blog provided a nice script to look through your installed gems and list out any compiled gems that need to be upgraded for 64-bit.

If you've manually compiled Ruby in /usr/local, you'll need to alter the script to point to the appropriate gem path by changing the following line:

# Dir.glob('/Library/Ruby/Gems/**/*.bundle').map do |path|
Dir.glob('/usr/local/lib/ruby/gems/**/*.bundle').map do |path|

Once you've generated the list of upgradable gems, you'll need to reinstall them. Simply updating may not rebuild the library, so you'll need to uninstall and then reinstall. There also seems to be some confusion on whether or not forcing the C extension to compile for 64-bit is necessary in Snow Leopard, but it doesn't seem to hurt. To do so, run your gem install command like so:

For more information on rebuilding your gems, check out this post from Victor Costan's blog. He also suggests running:

sudo gem update --system; sudo gem pristine --all

7. Upgrade remaining 32-bit libraries

This is where the fun begins. I'd suggest taking a peak into your /usr/local and /usr/local/lib folders to get an idea of what other libraries might still need updating. A few of the bigger ones for me include Git, Sphinx and RMagick.

Compiling Git

And another Hivelogic tutorial for the win: Compiling Git on Snow Leopard. You may need to upgrade some dependent libraries before building git will work (in my case, I needed libiconv).

Compiling Sphinx

iCoreTech put together a quick tutorial on getting Sphinx compiled for 64-bit - be sure to pay attention to the custom 64-bit configuration flags. My configuration looked like:

LDFLAGS="-arch x86_64" ./configure --prefix=/usr/local --with-mysql=/usr/local/mysql

Compiling ImageMagick and installing the RMagick gem

I've compiled a shell script to install the necessary dependencies, ImageMagick and the RMagick gem. It's an updated compilation of Agile Animal's and iCoreTech's scripts.

The updated script can be found at: http://pastie.org/620711. Simply save it as a .sh file and run it from the command line, like so: sh install_magick.sh

A Few Additional Notes and Resources

Hopefully this has gotten you through the bulk of upgrades needed to get back to work! But if not, here are a few other helpful resources that might help you out:

• Snow Leopard Ruby/Rails Developer Setup
• Fixing Ruby Gems, MySQL, and Passenger Phusion on Snow Leopard
• Install Passenger (mod_rails) in Snow Leopard 64-bit