About Jenkins' internal extension functionality, modules, and plugins
The data model and type hierarchy Jenkins is based on
Explains how Jenkins routes HTTP requests, and what ways to respond exist.
Introduction to persistent objects in Jenkins.
How Jenkins schedules tasks and how the queue works
Forms, data binding, and structured form submission
How to internationalize views and messages, and how to localize them.
The inner workings of the Jenkins CLI and how to write new commands
About Jenkins' internal extension functionality, modules, and plugins
About plugin governance, ownership, adoption, et.c
Guide to publishing plugins and related Jenkins project infrastructure
How to develop plugins for Blue Ocean
Preparing your development environment for Jenkins core and plugin development