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Ruby on Rails is one of the most popular application stacks for developers looking to create sites and web apps. The Ruby programming language, combined with the Rails development framework, makes app development simple.
You can easily install Ruby and Rails with the command-line tool rbenv. Using rbenv will provide you with a solid environment for developing your Ruby on Rails applications as it will let you easily switch Ruby versions, keeping your entire team on the same version. The project repository is located on [GitHub] ( https://github.com/rbenv/rbenv).
rbenv provides support for specifying application-specific versions of Ruby, lets you change the global Ruby for each user, and allows you to use an environment variable to override the Ruby version.
This tutorial will take you through the Ruby and Rails installation process via rbenv.
To follow this tutorial, you need:
One Ubuntu 16.04 server with a [non-root user] (
##Update and install dependencies
First, we should update
apt-get since this is the first time we will be using
apt in this session. This will ensure that the local package cache is updated.
sudo apt-get update
Next, let’s install the dependencies required for rbenv and Ruby with
sudo apt-get install autoconf bison build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev libgdbm3 libgdbm-dev
Once we have all of the required system dependencies installed, we can move onto the installation of rbenv itself.
Now we are ready to install rbenv. Let’s clone the rbenv repository from git. You should complete these steps from the user account from which you plan to run Ruby.
git clone https://github.com/rbenv/rbenv.git ~/.rbenv
From here, you should add
~/.rbenv/bin to your
$PATH so that you can use rbenv’s command line utility. Also adding
~/.rbenv/bin/rbenv init to your
~/.basrc file will let you load rbenv automatically.
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
Next, source rbenv by typing:
You can check to see if rbenv was set up properly by using the
type command, which will display more information about rbenv:
Your terminal window should output the following:
rbenv is a function
if [ "$#" -gt 0 ]; then
case "$command" in
rehash | shell)
eval "$(rbenv "sh-$command" "$@")"
command rbenv "$command" "$@"
In order to use the
rbenv install command, which simplifies the installation process for new versions of Ruby, you should install [ruby-build] (
https://github.com/rbenv/ruby-build), which we will install as a plugin for rbenv through git:
git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build
At this point, you should have both rbenv and ruby-build installed, and we can move on to installing Ruby.
With the ruby-build rbenv plugin now installed, we can install whatever versions of Ruby that we may need through a simple command. First, let’s list all the available versions of Ruby:
rbenv install -l
The output of that command should be a long list of versions that you can choose to install.
We’ll now install a particular version of Ruby. It’s important to keep in mind that installing Ruby can be a lengthy process, so be prepared for the installation to take some time to complete.
As an example here, let’s install Ruby version 2.5.0, and once it’s done installing, we can set it as our default version with the
rbenv install 2.5.0
rbenv global 2.5.0
If you would like to install and use a different version, simply run the
rbenv commands with a different version number, as in
rbenv install 2.3.0 and
rbenv global 2.3.0.
Verify that Ruby was properly installed by checking your version number:
If you installed version 2.5.0 of Ruby, your output to the above command should look something like this:
ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-linux]
You now have at least one version of Ruby installed and have set your default Ruby version. Next, we will set up gems and Rails.
##Working with Gems
Gems are packages that extend the functionality of Ruby. We will want to install Rails through the
So that the process of installing Rails is less lengthy, we will turn off local documentation for each gem we install. We will also install the bundler gem to manage application dependencies:
echo "gem: --no-document" > ~/.gemrc
gem install bundler
You can use the
gem env command (the subcommand
env is short for
environment) to learn more about the environment and configuration of gems. You can check the location where gems are being installed by using the
home argument, which will show the pathway to where gems are installed on your server.
gem env home
Your output should look something like this, with sammy being the name of the user:
Once we have gems set up, we can move on to install Rails.
As the same user, you can install the most recent version of Rails with the
gem install command:
gem install rails
If you would like to install a specific version of Rails, you can list the valid versions of Rails by doing a search, which will output a long list of possible versions. We can then install a specific version, such as 4.2.7:
gem search '^rails$' --all
gem install rails -v 4.2.7
rbenv works by creating a directory of shims, which point to the files used by the Ruby version that’s currently enabled. Through the
rehash sub-command, rbenv maintains shims in that directory to match every Ruby command across every installed version of Ruby on your server. Whenever you install a new version of Ruby or a gem that provides commands, like Rails does, you should run:
Verify that Rails has been installed properly by printing its version, with this command:
If it installed properly, you will see the version of Rails that was installed:
At this point, you can begin testing your Ruby on Rails installation and start to develop web applications.
As we installed rbenv manually using git, we can upgrade our installation to the most recent version at any time:
This will ensure that we are using the most up-to-date version of rbenv available.
##Uninstalling Ruby versions
As you download more versions of Ruby, you may accumulate more versions than you would like in your
Use the ruby-build plugin to automate the removal process with the
uninstall subcommand. For example, typing this will uninstall Ruby version 2.1.3:
rbenv uninstall 2.1.3
rbenv uninstall command you can clean-up your versions of Ruby so that you do not have more installed than you are currently using.
We have covered the basics of how to install rbenv and Ruby on Rails here so that you can use multiple Ruby environments. For your next steps, you can learn more about making those environments more robust. For more scalability, centralization, and control in your Ruby on Rails application, you may want to use it with [PostgreSQL] ( https://www.digitalocean.com/community/tutorials/how-to-use-postgresql-with-your-ruby-on-rails-application-on-ubuntu-14-04) or [MySQL] ( https://www.digitalocean.com/community/tutorials/how-to-use-mysql-with-your-ruby-on-rails-application-on-ubuntu-14-04) rather than its default sqlite3 database. As your needs grow, you can also learn how to [scale Ruby on Rails applications across multiple servers] ( https://www.digitalocean.com/community/tutorials/how-to-scale-ruby-on-rails-applications-across-multiple-droplets-part-1).