Install Ruby

Ruby Recommendations

Ruby 3.0 and above is recommended.

On a new system, the recommended way to install Ruby is via rbenv. Here are 2 ways to install rbenv:

Install rbenv with git
Install rbenv with homebrew

1. Install rbenv with git

You can also simply install rbenv by cloning down the rbenv repo to ~/.rbenv.

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

cat << 'EOF' >> ~/.bash_profile
export PATH="$HOME/.rbenv/bin:$PATH"
eval "$(rbenv init -)"
EOF

# install ruby-build as an rbenv plugin
mkdir -p ~/.rbenv/plugins
git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build

With the rbenv git approach, you’ll be able to use the latest available rubies by updating the ruby-build plugin repo directly.

cd ~/.rbenv/plugins/ruby-build && git pull

Then install different ruby versions. Example:

rbenv install 3.2.2
rbenv global 3.2.2
echo 3.2.2 > ~/.ruby-version # on some systems this is needed

Start a new terminal and confirm that you’re using ruby provided by rbenv. You should see something like this:

$ type ruby
ruby is /Users/tung/.rbenv/shims/ruby

Uninstall Ruby and rbenv

The nice thing about using rbenv is that the Ruby installation is isolated to ~/.rbenv. So you could always remove it with:

rm -rf ~/.rbenv

And removing the 2 lines of rbenv configuration in ~/.bash_profile.

2. Install rbenv with homebrew

You can install rbenv with homebrew also:

brew install rbenv

You should see something like this:

$ type rbenv
rbenv is /usr/local/bin/rbenv
$ type ruby-build
ruby-build is /usr/local/bin/ruby-build

Note, ruby-build is installed as a part of rbenv by brew.

Rbenv installs different versions of ruby in the ~/.rbenv folder. To complete the setup process: Add this to your ~/.bash_profile

export PATH="$HOME/.rbenv/bin:$PATH"
eval "$(rbenv init)"

And start a new terminal. You should be able see something like this:

$ type ruby
ruby is /Users/tung/.rbenv/shims/ruby

Then install different ruby versions. Example:

rbenv install 3.2.2
rbenv global 3.2.2
echo 3.2.2 > ~/.ruby-version # on some systems this is needed

Uninstall Ruby and rbenv

To uninstall with homebrew:

brew uninstall rbenv

Notes

With rbenv, you sometimes have to run rbenv rehash to generate the shims.
rvm is also ruby version manager similar to rbenv and is another way to install and manage multiple versions of ruby.
Generally, have not used brew install ruby because it doesn’t always to seem to regenerate the right executables in /usr/local/bin when installing gems.