# Package composition

The `package` keyword in `build.yml` allows packages to be built from other existing packages or components of existing packages.

## Known Issues

* [ ] included packages must exist and be installed locally
* [ ] only package instances with the `latest` tag can be included
* [ ] users are not warned when information from private packages is included in new packages that are later made published

Example `build.yml`:

```yaml
---
contents:
  NODENAME:                                     # Create a package with a node called `NODENAME`
    package: OWNER/EXISTING_PACKAGE/DATAFRAME   # Pull its contents from a node, `DATAFRAME`, in an
                                                # existing package, `OWNER/EXISTING_PACKAGE`.
```


---

# Agent Instructions: 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:

```
GET https://docs.quilt.bio/quilt-2-master/advanced-usage/compose.md?ask=<question>
```

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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.