> For the complete documentation index, see [llms.txt](https://docs.feast.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.feast.dev/master/getting-started/concepts/feature-repo.md). # Feature repository ## Feature repository Feast users use Feast to manage two important sets of configuration: * Configuration about how to run Feast on your infrastructure * Feature definitions With Feast, the above configuration can be written declaratively and stored as code in a central location. This central location is called a feature repository. The feature repository is the declarative source of truth for what the desired state of a feature store should be. A feature repository is the collection of python files that define entities, feature views and data sources. Feature Repos also have a `feature_store.yaml` file at their root. Users can collaborate by making and reviewing changes to Feast object definitions (feature views, entities, etc.) in the feature repo. But, these objects must be applied, either through API, or the CLI, for them to be available by downstream Feast actions (such as materialization, or retrieving online features). Internally, Feast only looks at the registry when performing these actions, and not at the feature repo directly. ## Declarative Feature Definitions When using the CLI to apply changes (via `feast apply`), the CLI determines the state of the feature repo from the source files and updates the registry state to reflect the definitions in the feature repo files. This means that new feature views are added to the registry, existing feature views are updated as necessary, and Feast objects removed from the source files are deleted from the registry. For more details, see the [Feature repository](/master/reference/feature-repository.md) reference. --- # 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.feast.dev/master/getting-started/concepts/feature-repo.md?ask=&goal= ``` `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.