Howto install Rails 5 from beta or git and create a new application

First things first:

Rails 5 supports only Ruby version 2.2.2 and up

I recommend to install the latest Ruby 2.2.4 - in rbenv:

rbenv update
rbenv install 2.2.4
rbenv global 2.2.4

1. Install beta or release candidate from the prelease gem

Beta or RC gems are released on rubygems.org, but are not installed by default.

gem install rails --pre (currently it installs 5.0.0.beta1)
rails _5.0.0.beta1_ new myrails5app

1. Install from a GIT repository

TODO: I just copied this from: http://stackoverflow.com/questions/3821077/how-to-create-edge-rails-application, need to verify some day, but seems legit.

git clone https://github.com/rails/rails.git
cd rails/
bundle install
cd ../
./rails/railties/exe/rails new myapp --edge --dev

That’s all!