The ‘as code’ paradigm is about being able to reproduce and/or restore a full environment within minutes based on recipes and automation, managed as code.
Setting up Jenkins is a complex process, as both Jenkins and its plugins require some tuning and configuration, with dozens of parameters to set within the web UI manage section.
Jenkins Configuration as Code allows to define this whole configuration as a simple, human-friendly, plain text yaml syntax. Without any manual step this configuration can be validated and applied to a Jenkins master in fully a reproducible way. With JCasC setting up a new Jenkins master will become a no-brainer event.
Fully working Jenkins master with:
no hands on keyboard
no click on UI
No need to write glue code for every supported plugin
Most plugins supported out of the box
Others can bundle adapter code
You can ask questions about it on the regular Jenkins Developer mailling list (just prefix with [JCasC]).
The source code
Feature requests, bugs and so on are currently tracked via the github issue tracker