Installing Ruby using rbenv on your WSL Ubuntu system is a great way to manage multiple Ruby versions. Below are the step-by-step instructions:

Step 1: Update Your Package List

First, ensure your package list is up to date.

sudo apt update

Step 2: Install Dependencies

Install the necessary dependencies for rbenv and Ruby.

sudo apt install -y build-essential libssl-dev libreadline-dev zlib1g-dev libffi-dev libyaml-dev

Step 3: Install rbenv

Clone the rbenv repository from GitHub and add it to your shell.

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

Step 4: Install ruby-build

Clone the ruby-build repository into the rbenv plugins directory.

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

Step 5: Install Ruby

List all available Ruby versions.

rbenv install -l

Install your desired Ruby version (replace 3.3.4 with the version you want to install).

rbenv install 3.3.4
rbenv global 3.3.4 # to activate this Ruby version as the new default

Step 6: Verify the Installation

Check the Ruby version to ensure it was installed correctly.

ruby -v

Step 7: Install Bundler

Install the Bundler gem, which is essential for managing Ruby project dependencies.

gem install bundler

Step 8: Rehash rbenv

Rehash rbenv to ensure it recognizes the new Ruby installation.

rbenv rehash

Additional Notes

• Updating rbenv and ruby-build: Occasionally, you might need to update rbenv and ruby-build. You can do this by navigating to their respective directories and pulling the latest changes from GitHub:

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

• Switching Ruby Versions: To switch Ruby versions, simply install the desired version and set it globally or locally for a specific project:

rbenv install x.x.x
rbenv global x.x.x  # For system-wide
# or
rbenv local x.x.x   # For a specific project

Following these steps will help you successfully install and manage Ruby versions using rbenv on your WSL Ubuntu system.