It used to be a jarring experience to setup a new machine for development, but progress has paved the dirt road into a silky smooth autobahn. These are the tools we use today:

1. Homebrew: Remember how painful it used to be to get imagemagick installed? Now it takes about a minute. “brew install imagemagick”. Same story for git and other Linux dependencies.
2. rbenv/ruby-build: We have some apps running on Ruby 1.8.7, some on 1.9.2, and some on 1.9.3. ruby-build makes it easy to compile all three, rbenv makes it easy to switch between them on a per-project basis. We run rbenv in production as well, so all you need to do to change the Ruby version there is alter .rbenv-version—development and production is always on the same page.
3. Bundler: Not everyone at 37signals loved Bundler at first, but now that it’s stable, they’ve been won over. I now curse whenever I have to use an old application that hasn’t been setup with Bundler. Manually tracing down dependencies?! How prehistoric!
4. rake setup: All our apps has a rake setup task that’ll run bundler, create the databases, import seeds, and install any auxiliary software (little these days) or do any other setup. So when you git clone a new app, you know that “rake setup” will take care of you.
5. Pow: No more messing with Apache or nginx for local development. All it takes for Pow to add another app is a symlink. All the apps are always configured and available at basecamp.dev, highrise.dev, etc without messing with the hosts file either.

Thanks to Max Howell for Homebrew, Sam Stephenson for rbenv/ruby-build and Pow, and Carl Lerche/Yehuda Katz for Bundler. Thanks to them, starting from scratch has never been easier.

[Some new stuff to try out. RVM hasn’t really lit me up…]
Source: SIGNAL VS. NOISE