The Twelve-Factor App

• https://12factor.net/
• http://www.heroku.com/
• http://blog.heroku.com/archives/2011/6/28/the_new_heroku_4_erosion_resistance_explicit_contracts/
• https://books.google.com/books/about/Patterns_of_enterprise_application_archi.html?id=FyWZt5DdvFkC
• https://books.google.com/books/about/Refactoring.html?id=1MsETFPD3I0C
• https://github.com/heroku/12factor
• https://www.heroku.com/policy/privacy