Implementation
Get to know the Umbraco codebase. Developing an application requires knowledge about the tool you're working with. This section will give you an introduction to the structure of Umbraco.
You are currently looking at documentation for Umbraco 8 and older versions.
An automated guess is that docs.umbraco.com/umbraco-cms/implementation/ could be the link to the new documentation for Umbraco 9 and newer versions.
Get to know the Umbraco codebase. Developing an application requires knowledge about the tool you're working with. This section will give you an introduction to the structure of Umbraco.