My notes on creating a Rails 4.2 app for hosting on Heroku. With RSpec and Postgresql.

    # Install RVM, Ruby and Bundler
    ...

    # Install Rails
    gem install rails --no-ri --no-rdoc

    # Create new app without Test::Unit, and for Postgresql (for Heroku)
    rails new MYAPP --skip-test-unit --database=postgresql

    # add back `sqlite gem for local dev
    gem 'sqlite'
    # add rspec to Gemfile:
    gem 'rspec-rails'

    bundle install
    rails g rspec:install

    # create heroku app
    heroku apps:create MYAPP

    # add heroku Postgresql database
    heroku addons:add heroku-postgresql:hobby-dev
    # for documentation: `heroku addons:docs heroku-postgresql`

    # push to Heroku
    git push heroku master

    # rake db:migrate
    heroku run rake db:migrate