---
title: Coveo indexing pipeline extensions
slug: n8se0373
canonical_url: https://docs.coveo.com/en/n8se0373/
collection: adobe
source_format: adoc
---
# Coveo indexing pipeline extensions

:figure-caption!:

Items crawled in Adobe Experience Manager are then sent to the [Coveo Platform](https://docs.coveo.com/en/186/) [document processing manager (DPM)](https://docs.coveo.com/en/191/) to be processed and indexed.

The [document processing manager (DPM)](https://docs.coveo.com/en/191/) provides two [indexing pipeline extension (IPE)](https://docs.coveo.com/en/206/) stages during which you can modify your items, using Python code, before they're indexed.
The [choice of stage](#choosing-between-a-pre-conversion-and-a-post-conversion-extension) depends on your use case.

**Indexing process showing the pre-conversion and post-conversion extension stages you can leverage to customize the process.**
![The Coveo indexing pipeline](https://docs.coveo.com/en/assets/images/coveo-for-adobe/simplified-indexing-pipeline-stages.png)

> **Note**
>
> Don't use indexing pipeline extensions for tasks that the connector itself is designed to handle.
> For example, when using the [Web](https://docs.coveo.com/en/malf0160/) or [Sitemap](https://docs.coveo.com/en/1967/) connector, you shouldn't use an IPE to remove unwanted sections of web pages.
> These connectors support [web scraping](https://docs.coveo.com/en/2767/) configurations for that very purpose.

## Choosing between a pre-conversion and a post-conversion extension

An important stage of the [Coveo indexing pipeline](https://docs.coveo.com/en/184/) is the [Processing](https://docs.coveo.com/en/1893#processing) stage.
During this stage, incoming items are converted to an index-ready format.
Coveo provides indexing pipeline extension stages prior to this conversion stage and after it.

**Examples of use cases for pre-conversion extensions**:

* Rejecting a web page using advanced rules.

* Formatting values.

**Examples of use cases for post-conversion extensions**:

* Modifying the body of a page.

* Adding or modifying metadata.

If you're unsure about the stage to choose, see our [decision table](https://docs.coveo.com/en/1556#pre-conversion-versus-post-conversion).

Once you've chosen the appropriate stage, you can [create your indexing pipeline extension](https://docs.coveo.com/en/1645#add-an-indexing-pipeline-extension).