About deprecations in this version of Puppet
Included in Puppet Enterprise 2017.1.
Puppet 4.0 removed or changed a lot of old and crufty features that had a long period of deprecation in Puppet 3.x (or sometimes even earlier).
While the 3.x deprecations focused mostly on the Puppet language and longstanding problems with built-in resource types, the 4.x deprecations focus on Puppet’s infrastructure.
How to tell if you’re using deprecated features
As Puppet 5 draws closer, you should read through the deprecation pages in this section. Each page groups similar features together, and each feature explains what to do if you’re affected.