> For the complete documentation index, see [llms.txt](https://docs.umbraco.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.umbraco.com/umbraco-cms/13.latest/fundamentals/code.md).

# Code

## [Using Umbraco's Service APIs](/umbraco-cms/13.latest/fundamentals/code/umbraco-services.md)

Create and update entities in Umbraco from code.

## [Subscribing to Notifications](/umbraco-cms/13.latest/fundamentals/code/subscribing-to-notifications.md)

Subscribe to notifications to execute custom code on a number of operations.

## [Creating Forms](/umbraco-cms/13.latest/fundamentals/code/creating-forms.md)

Create, submit and handle HTML forms with controllers.

## [Debugging your Umbraco site](/umbraco-cms/13.latest/fundamentals/code/debugging.md)

Using Tracing and MiniProfiler to debug your code.

## [Source/Version Control](/umbraco-cms/13.latest/fundamentals/code/source-control.md)

General advice on source controlling your Umbraco implementation.


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