# Data Backends [Data sources](../../models/core/datasource.md) can be defined to reference data which exists on systems of record outside NetBox, such as a git repository or Amazon S3 bucket. Plugins can register their own backend classes to introduce support for additional resource types. This is done by subclassing NetBox's `DataBackend` class. ```python title="data_backends.py" from netbox.data_backends import DataBackend class MyDataBackend(DataBackend): name = 'mybackend' label = 'My Backend' ... ``` To register one or more data backends with NetBox, define a list named `backends` at the end of this file: ```python title="data_backends.py" backends = [MyDataBackend] ``` !!! tip The path to the list of search indexes can be modified by setting `data_backends` in the PluginConfig instance. ::: netbox.data_backends.DataBackend