# Configuring Sources

Preen maintains a configuration file in `$HOME/.preen/sources.yml` by default. This is can be overridden via the `PREEN_CONFIG_PATH` environment variable.

A config file might look like this:

```yaml
sources:
  - name: s3-model
    engine: s3
    connection:
      bucket_name: users
      region: us-east-1
  - name: postgres-model
    engine: postgres
    connection:
      host: localhost
      port: 33061
      database: postgres
      username: root
      password: myp@assword
  - name: mongo-model
    engine: mongodb
    connection:
      host: ${MONGO_HOST}
      port: ${MONGO_PORT}
      database: mongo
```

In a nutshell, your configuration is primarily a list of data sources, credentials, and their engine classification (see [Config](/preen-docs/documentation/config.md)for list of supported engines). **Be sure to add this file to your `.gitignore` if you are keeping it somewhere version controlled.**


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# 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://preen.gitbook.io/preen-docs/getting-started/hello-world/configuring-sources.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
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.