Hiera

Hiera is a key/value lookup tool for configuration data, built to make Puppet better and let you set node-specific data without repeating yourself." [Puppetlabs]

PThe hierarchical structure is defined inside the hiera.yaml file and you can find it inside the main project folder. It points to the data folder containing a certain number of yaml file that belong to the hierarchical structure defined in the hiera.yaml file.

Librarian

The librarian Puppetfile allows defining module dependencies from several sources with version control, having a file that defines your dependencies: the Puppetfile. The Puppetfile is placed in the main project directory.