Updated December 15th, 2013:
- Updated install link for homebrew, it has changed
- Updated Xcode install instructions for Mac OS X Mavericks
- Bumped ruby 1.9.3 version from 1.9.3p448 to 1.9.3p484
- Bumped ruby 2.0.0 version from 2.0.0p247 to 2.0.0p353
Updated July 9th, 2013:
- Bumped ruby 1.9.3 version from 1.9.3p429 to 1.9.3p448
- Bumped ruby 2.0.0 version from 2.0.0p195 to 2.0.0p247
- Removed openssl workaround for compiling ruby 2.0.0 on Mac OS X - this has been fixed
Out of the box, Ruby does not provide a mechanism to support multiple installed versions. Rbenv makes managing multiple versions of Ruby easy. It’s a great way to work on current development projects using Ruby 1.9.x and be able to switch to Ruby 2.0.x for new work. Rbenv is a lightweight alternative to Ruby Version Manager (RVM). Rbenv does not include a way to manage gems, like with RVM, though most people prefer to use Bundler gem management instead.
Rbenv is supported on Linux and Mac OS X. Rbenv doesn’t work on Windows (and isn’t really necessary on Windows as there is no system Ruby on Windows). On Windows, the RubyInstaller and/or Pik are both good alternatives to work with multiple versions of Ruby on the same box.
NOTE: Rbenv is incompatible with RVM because RVM overrides the
gem command with a function. If you want to switch to Rbenv,
make sure you uninstall RVM first. Run the following commands to uninstall
RVM:
$ rvm implode
$ gem uninstall rvm
Then remove/comment out the RVM loader line in .bash_profile
and/or .bashrc
Mac OS X
Install Rbenv and Ruby 1.9.x - Mac OS X
First you’ll need to install a C compiler and some other command line tools to build Ruby from source. You’ll need to install the Xcode Command Line Tools:
Mac OS X Mavericks 10.9
If you are using the latest version of Mac OS X Mavericks, it has support for downloading the Xcode command line tools directly from a Terminal window. Run the following on a command line:
$ xcode-select --install
You will be prompted to either click on Install to just install the command
line developer tools or click on Get Xcode to install both Xcode and the
command line developer tools. It can be handy to have Xcode as well, but
it is a rather large multi-gigabyte download and not really necessary for
Ruby development. So if you want to get going quickly, just click on the
Install button:
Mac OS X Snow Leopard 10.8 (and earlier)
Versions of Mac OS X prior to Mavericks, like Snow Leopard do not have built-in support for downloading the Xcode command line developer tools, but you can download them directly from the Apple Developer web site developer.apple.com/downloads. Here are the current direct download links for the Xcode command line tools as of this writing. Download the applicable package for your version of Mac OS X:
- Xcode Command Line Tools for Mac OS X Mountain Lion 10.8
- Xcode Command Line Tools for Mac OS X Lion 10.7
Once you have downloaded the .dmg file, double-click on the .dmg to open it, then double-click on the .mpkg file to run the Command Line Tools installer:
If you have time to install Xcode, it’s handy to have it around, though not really required for Ruby development. If you are running Mac OS X Mountain Lion 10.8, you will need to make sure that you have OS X version 10.8.4 or later to install Xcode, otherwise the App Store will issue the following complaint:
Download and install the latest version of Xcode from the App Store.
Then install the Command Line Tools by choosing the menu item
Xcode -> Preferences... to display the Downloads dialog.
Click on the Downloads tab, then click on the download arrow to the right
of the Command Line Tools component to install.
Next, you’ll need to install the Homebrew package manager to get all the dependencies needed to compile Ruby from source. While you could manage these dependencies by hand, using a package manager is a better idea, as package managers know how to uninstall what they install.
Run the following command to install Homebrew:
$ ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"
Run brew doctor and address any issues it discovers. When
all is well, you should see:
$ brew doctor
Your system is raring to brew.
Next, install the additional dependencies to compile Ruby from source:
# For update-system
brew update
brew tap homebrew/dupes
# For ruby
brew install apple-gcc42
And now install rbenv and the ruby-build plugin:
brew update
brew install rbenv
brew install ruby-build
Add rbenv init to your shell to enable shims and autocompletion:
$ echo 'eval "$(rbenv init -)"' >> $HOME/.bash_profile
$ source ~/.bash_profile
Restart shell as a login shell so that the PATH changes take effect:
$ exec $SHELL -l
Install the latest version of ruby 1.9.x (at the time of this writing 1.9.3-p484)
$ rbenv install 1.9.3-p484
Rebuild the shim executable
$ rbenv rehash
You’ll need to run rbenv rehash every time you install a new version of Ruby
or install a new gem.
Set the latest version of ruby to be the default version of ruby
$ rbenv global 1.9.3-p484
Verify the ruby install. If everything was installed correctly, the ruby -v
command should report that version 1.9.3p484 is installed.
$ ruby -v
ruby 1.9.3p484 (2013-11-22 revision 43786) [x86_64-darwin13.0.0]
Install Bundler - Mac OS X
You’ll need to use Bundler to manage gems. Installing a gem is also a good way to ensure that you’ve installed most of the Ruby prerequisites.
First, make sure you update to the latest version of Rubygems:
$ gem update --system
Updating rubygems-update
Fetching: rubygems-update-2.1.11.gem (100%)
Successfully installed rubygems-update-2.1.11
Installing RubyGems 2.1.11
RubyGems 2.1.11 installed
...
Then install the bundler gem. If the gem install command reports
Successfully installed you’re good to go:
$ gem install bundler
Successfully installed bundler-1.3.5
Parsing documentation for bundler-1.3.5
1 gem installed
$ rbenv rehash
Install Ruby 2.0.0 - Mac OS X
As of this writing, Ruby 2.0.0-p353 is the latest version of Ruby 2.0.0.
Use rbenv install --list to print out the available versions. To install:
$ rbenv install 2.0.0-p353
To verify the install:
$ rbenv local 2.0.0-p353
$ ruby -v
ruby 2.0.0p353 (2013-11-22 revision 43784) [x86_64-darwin13.0.0]
If you want to make Ruby 2.0.0 the global default version of ruby:
$ rbenv global 2.0.0-p353
Upgrade Rbenv - Mac OS X
To upgrade rbenv via homebrew:
$ brew update
$ brew upgrade rbenv
$ brew upgrade ruby-build
Remove Rbenv - Mac OS X
Uninstall the packages you installed via homebrew:
brew uninstall rbenv
brew uninstall ruby-build
Remove the following directory:
rm -rf $HOME/.rbenv
And remember to remove whatever you added to $HOME/.bash_profile
Linux
Install Rbenv and Ruby 1.9.x - Linux
Make sure the prerequisite packages are installed.
Ubuntu prerequisites:
$ sudo apt-get update
$ sudo apt-get install -y build-essential git
$ sudo apt-get install -y libxml2-dev libxslt-dev libssl-dev
RHEL/CentOS prerequisites:
$ sudo yum update
$ sudo yum install -y git
$ sudo yum install -y gcc-c++ patch readline readline-devel zlib zlib-devel
$ sudo yum install -y libyaml-devel libffi-devel openssl-devel make bzip2
$ sudo yum install -y autoconf automake libtool bison
$ sudo yum install -y libxml2-devel libxslt-devel
Download the rbenv source distribution to $HOME/.rbenv:
$ git clone git://github.com/sstephenson/rbenv.git $HOME/.rbenv
Add $HOME/.rbenv/bin to your $PATH
$ echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> $HOME/.bashrc
Add rbenv init to your shell to enable shims and autocompletion:
$ echo 'eval "$(rbenv init -)"' >> $HOME/.bashrc
Restart shell as a login shell so that the PATH changes take effect:
$ exec $SHELL -l
Install the ruby-build plugin, which provides an
rbenv install command to simplify the process of compiling
and install new Ruby versions:
$ git clone git://github.com/sstephenson/ruby-build.git $HOME/.rbenv/plugins/ruby-build
Install the latest version of ruby 1.9.x (at the time of this writing 1.9.3-p484)
$ rbenv install 1.9.3-p484
Rebuild the shim executable
$ rbenv rehash
You’ll need to run rbenv rehash every time you install a new
version of Ruby or install a new gem.
Set the latest version of ruby to be the default version of ruby
$ rbenv global 1.9.3-p484
Verify the ruby install. If everything was installed correctly, the
ruby -v command should report that version 1.9.3p484 is installed.
$ ruby -v
ruby 1.9.3p484 (2013-11-22 revision 43786) [x86_64-linux]
Install Bundler - Linux
You’ll need to use Bundler to manage gems. Installing a gem is also a good way to ensure that you’ve installed most of the Ruby prerequisites.
First, make sure you update to the latest version of Rubygems:
$ gem update --system
Then install the bundler gem. If the gem install command reports
Successfully installed you’re good to go:
$ gem install bundler
Successfully installed bundler-1.3.5
Parsing documentation for bundler-1.3.5
1 gem installed
$ rbenv rehash
Install Ruby 2.0.0 - Linux
As of this writing, Ruby 2.0.0-p353 is the latest version of Ruby 2.0.0.
Use rbenv install --list to print out the available versions. To install:
$ rbenv install 2.0.0-p353
To verify the install:
$ rbenv local 2.0.0-p353
$ ruby -v
ruby 2.0.0p353 (2013-11-22 revision 43784) [x86_64-linux]
If you want to make Ruby 2.0.0 the global default version of ruby (but currently Chef requires Ruby 1.9.x):
$ rbenv global 2.0.0-p353
Upgrade Rbenv - Linux
Since Rbenv is a Git repository, upgrading is just a matter of refreshing the source:
$ cd $HOME/.rbenv
$ git pull
Remove Rbenv - Linux
To uninstall/remove Rbenv, remove the following directory:
$ rm -rf $HOME/.rbenv
And remember to remove whatever you added to $HOME/.bash_profile