Install Ruby and Rails on Windows 10, Ubuntu, and OS X

This is a guide to install Ruby and the web development framework Rails on Windows 10, OS X 10.11 "El Capitan", and Ubuntu 16.04 "Xenial Xerus".

Install Ruby and Rails on Windows 10

1. Join the Windows Insider program by Microsoft.
2. Update your Windows via the Windows 10 Upgrader and Settings > Update & Security > Windows Update.
3. Enable the Developer Mode in Settings > Update & Security > For Developers.
4. Install the Windows Subsystem for Linux in Control Panel > Programs and Features > Turn Windows Features On or Off.
5. Run bash form your Start Menu and follow the installation process. The password you set for your user account will be your sudo password. Do not lose it!
6. Run Bash on Ubuntu for Windows from your Start Menu. It got an Ubuntu logo now.
7. You are now in a basic Ubuntu 14.04 environment in Windows 10 and are able to run Linux applications!
8. From this point on you can follow the instructions for Ubuntu.
9. There might be some premission error with bundler which you can fix with chmod +t -R ~/.bundle inside the folder of the Rails project.
10. The local development server will also be reachable in your Windows environment on localhost:3000.

Install Ruby and Rails on Ubuntu 16.04

1. Update your system with sudo apt-get update and sudo apt-get dist-upgrade and clean up with sudo apt-get autoclean.
2. Install a bunch of dependencies with sudo apt-get install git-core curl zlib1g-dev build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev python-software-properties libffi-dev.
3. Go to your home directory with cd and get rbenv and its ruby-build plugin via git clone https://github.com/rbenv/rbenv.git ~/.rbenv and git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build. Import them to your shell with echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc, echo 'eval "$(rbenv init -)"' >> ~/.bashrc, and echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bashrc. Then reload your shell with exec $SHELL.
4. Now it is time to get Ruby with rbenv install 2.3.1 and point your shell to it with rbenv global 2.3.1. Check if it worked with ruby -v and gem -v.
5. Update your gems with gem update --system and gem update. Also get bundler with gem install bundler. Do rbenv rehash afterwards.
6. Modern Rails has a lot of depencencies to JavaScript so we need to get Node.js (including npm) via curl -sL https://deb.nodesource.com/setup_4.x | sudo -E bash - and sudo apt-get install nodejs. Check if it works with node -v and npm -v
7. Now finally we get Rails with gem install rails -v 4.2.7 and rbenv rehash. Check if it works with rails -v.
8. The final check will be done with rails new anapp, followed by cd anapp, and rails s. The local development server will be reachable on localhost:3000.

Install Ruby and Rails on OS X 10.11

1. Update your system via App Store > Updates.
2. Install Homebrew with ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)". You enter all this commands into Terminal or iTerm.
3. Install rbenv and its ruby-build plugin via Homebrew with brew install rbenv ruby-build. Import them to your shell with echo 'if which rbenv > /dev/null; then eval "$(rbenv init -)"; fi' >> ~/.bash_profile and source ~/.bash_profile.
4. Now it is time to get Ruby with rbenv install 2.3.1 and point your shell to it with rbenv global 2.3.1. Check if it worked with ruby -v and gem -v. If something does not work close Terminal or iTerm completly, start it again, and try again.
5. Update your gems with gem update --system and gem update. Also get bundler with gem install bundler. Do rbenv rehash afterwards.
6. Modern Rails has a lot of depencencies to JavaScript so we need to get Node.js (including npm) via Homebrew with brew install node. Check if it works with node -v and npm -v
7. Now finally we get Rails with gem install rails -v 4.2.7 and rbenv rehash. Check if it works with rails -v.
8. The final check will be done with rails new anapp, followed by cd anapp, and rails s. The local development server will be reachable on localhost:3000.

Other Versions

If you want to install other versions than given above you can do that. If you know the version you need, then just replace that version number with those I gave. If you are not sure which versions are avaivable then do:

• rbenv install --list for Ruby
• gem list rails --remote --all for Rails

For the case that you want to use the more current but less stable Node.js 6 do this instead of the given above:

• curl --silent --location https://rpm.nodesource.com/setup_6.x | bash -.

Install and use PostgreSQL with Ruby on Rails with OS X

1. Update your system via App Store > Updates.
2. Install Postgress.app with normal drag and drop install procedure and start it.
3. Install the pg gem manually (not with bundler) with gem install pg -- --with-pg-config=/Applications/Postgres.app/Contents/Versions/latest/bin/pg_config.
4. Your PostgreSQL database is now running at localhost:5432.