Paralellize gem installs

You can paralellize the installation of gems with bundler's jobs feature.

To use, simply run:

bundle install --jobs 3

This only works for bundler 1.4 or above

Or to enable globally for all future bundling:

bundle config --global jobs 3

Obviously jobs is the number you want to parallelize. Pick the number one less than the number of cores you have. If you don't, you may get deadlock errors.

Credit to @xianpants for the tip!

Disable documentation

Create a file at ~/.gemrc with:

gem: --no-rdoc --no-ri

Unless, of course, you use local documentation.