When we say that we will be specifying our infrastructure as a code using Chef, what we mean is that we'll be writing code using domain-specific language (DSL) provided by Chef. This code will be executed by chef-client on the concerned machine, and the machine will be bootstrapped as per the guidelines we specify in our code. The DSL provided by Chef is very much like Rake tasks, and Ruby developers will find themselves at home when writing Chef code.

Chef DSL is actually a Ruby DSL, and one can use the full power of Ruby as a programming language when trying to write Chef code. The term "Chef code" is used loosely here, to specify recipes, roles, environments, templates, resources, attributes, libraries, and so on.

Chef provides a DSL that you can use to write your recipes and roles, describe environments, write custom resource providers and libraries, and so on.

The code that you'll write will be stored as Ruby files in the Chef repository. When these files are uploaded...