> 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-engage/17.latest/getting-started/for-developers/content-delivery-network-recommendations.md).

# Content Delivery Network recommendations

This article provides information and best practices on using Content Delivery Network (CDN) with Umbraco Engage.

## Pages (HTML)

Do not cache pages on the CDN level. Umbraco Engage is based on serving a unique page to every (returning) visitor. By enabling page caching every visitor will be assigned the same Umbraco Engage ID and Analytics, A/B testing, and Personalisation will not work correctly.

### Cache static files (CSS and JavaScript)

It is possible to cache static CSS and JavaScript files. Refer to the documentation of the CDN provider for the best-practice setup.

### Media files (Umbraco /media folder, images, and PDFs)

It is possible to cache `/media` files. Refer to the documentation of the CDN provider for best-practice setup.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.umbraco.com/umbraco-engage/17.latest/getting-started/for-developers/content-delivery-network-recommendations.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.