chruby - Installing and managing Ruby versions

Ruby with chruby

To install chruby and ruby-install:
brew install chruby ruby-install

To install Ruby using ruby-install:
ruby-install ruby 2.7.1

NOTE: You can find latest stable version of Ruby here: https://www.ruby-lang.org/en/downloads/
If you have issues installing Ruby then try the following:
brew install openssl@3
ruby-install 3.2.2 -- --with-openssl-dir=$(brew --prefix openssl@3)
chruby 3.2.2

Note: If you'd just installed a new Ruby version and chruby can't find it, it means you need to reload the terminal.

Add following to ~/.bash_profile or ~/.zshrc:
echo 'source /usr/local/opt/chruby/share/chruby/chruby.sh' >> ~/.bash_profile
echo 'source /usr/local/opt/chruby/share/chruby/auto.sh' >> ~/.bash_profile 
(auto.sh above enables auto-switching if Rubies specified by .ruby-version files)

To switch Ruby versions:
chruby 2.7.1

If you get this error: "zsh: command not found: chruby"
then you need to reload bash profile: $ source ~/.bash_profile

To list available Ruby versions:
chruby

To install Rails:
gem install rails -v 6.0.3.2 --no-document

If after this, you try to use a Rails command, e.g. $ rails new ...
and you receive the following error: "Rails is not currently installed on this system"
1) Then just open a new tab and/or reload bash profile, 
2) Switch to the Ruby version (e.g. 3.1.2)
3) Re-run required Rails command

Further information:
https://github.com/postmodern/chruby
https://blog.engineyard.com/how-to-install-ruby-on-a-mac-with-chruby-rbenv-or-rvm
https://ryanbigg.com/2015/06/mac-os-x-ruby-ruby-install-chruby-and-you

Other chruby gists:
- https://gist.github.com/rubyandcoffee/83b7bdffc8faf909e077da58ca1ec7ec

ruby-install ruby 2.7.1 should be ruby-install ruby-2.7.1, it seems...