chef

https://github.com/opscode/chef

Ruby

A systems integration framework, built to bring the benefits of configuration management to your entire infrastructure.

Chef::Resource.is_custom_resource!

This sets the resource to being a custom resource, and does so in a way
that automatically inherits to all subclasses via defining a method on
the class (class variables and class instance variables don't have the
correct semantics here, this is a poor man's activesupport class_attribute)

Source | Google | Stack overflow

Edit

git clone [email protected]:opscode/chef.git
cd chef
open lib/chef/resource.rb

Contribute

# Make a new branch

git checkout -b -your-name--update-docs-Chef--Resource-is_custom_resource--for-pr

# Commit to git

git add lib/chef/resource.rbgit commit -m "better docs for Chef::Resource.is_custom_resource!"

# Open pull request

gem install hub # on a mac you can `brew install hub`

hub fork

git push <your name> -your-name--update-docs-Chef--Resource-is_custom_resource--for-pr

hub pull-request

# Celebrate!