Ruby on Linux

Although many distros come with a system Ruby installed or a repository version, we suggest using a version manager such as rbenv or RVM. This will ensure you have an up to date Ruby version and a clean environment separated from your system Ruby.

The instructions for installing via rbenv on Ubuntu are provided below (since that is what we generally use).

Install Ruby via rbenv

Installing rbenv is a manual process, which is sort of nice because it is so minimal!

1. Install build dependencies

You will need these to build Gems:

sudo apt install autoconf bison build-essential libssl-dev libyaml-dev libreadline-dev zlib1g-dev libncurses5-dev libffi-dev libgdbm-dev

(this is based on the suggested build environment from ruby-build, slightly updated and tweaked for simplicity)

2. Install rbenv

Clone rbenv into your home directory:

git clone https://github.com/rbenv/rbenv.git ~/.rbenv

Then add it to PATH (this is for Ubuntu, if using a different distro check the location of your bash profile):

echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc

Close terminal and open a new one.

Next, follow the instructions given by the command rbenv init (this can be confusing, because rbenv init doesn’t do anything, it just prints out the instructions). Or just do this on Ubuntu:

echo 'eval "$(rbenv init -)"' >> ~/.bashrc

Close terminal and open a new one.

3. Add ruby-build

Clone ruby-build into the rbenv plugins directory:

git clone https://github.com/rbenv/ruby-build.git "$(rbenv root)"/plugins/ruby-build

4. Install a Ruby Version

Check the Ruby download page to find the latest stable version or your project requirements to find your desired Ruby version number.

Check rbenv install -l to get a list of available stable versions.

Use rbenv install + version number, e.g.:

rbenv install 3.2.2

This can take awhile since ruby-build will download and build from source.

Once complete, set the version you want to use:

rbenv global 3.2.2

Now, ruby -v should report what you just set.

Update rbenv and ruby-build

Since you installed the tools using git, to update rbenv and ruby-build you simply git pull the most recent master branch code.

cd ~/.rbenv && git pull
cd "$(rbenv root)"/plugins/ruby-build && git pull

Note: the list of available Ruby versions (rbenv install -l) is NOT automatically updated. So you should periodically update ruby-build following the git pull method above (i.e. cd ~/.rbenv/plugins/ruby-build && git pull).

Note: there is an Ubuntu package to install, so you can use sudo apt install rbenv ruby-build. Unfortunately ruby-build is super out of date, so it will only list very out-of-date versions of Ruby to install. As far as I can tell, this is not a good install method.