Rest.li supports [partial update](https://linkedin.github.io/rest.li/user_guide/restli_server#partial_update) natively without needing explicitly defined models.
This is because the rest.li endpoint will have the logic that performs the corresponding partial update based on the information in the model.
That said, it’s common to have fields that denote the list of items to be added or removed (e.g. `membersToAdd`&`membersToRemove` from below)
2. Similar to metadata [snapshots](snapshot.md), entity that supports metadata delta will add an entity-specific metadata delta
(e.g. `GroupDelta` from below) that unions all supported partial update models.
3. The entity-specific metadata delta is then added to the global `Delta` typeref, which is added as part of [Metadata Change Event](mxe.md#metadata-change-event-mce) and used during [Metadata Ingestion](../architecture/metadata-ingestion.md).