# HostingExtensions.UseCosmosClustering(ISiloBuilder)

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.clustering.cosmos/orleans.hosting.hostingextensions/) | [Methods](/orleans/docs/api/csharp/microsoft.orleans.clustering.cosmos/orleans.hosting.hostingextensions/methods/)

[Source](https://github.com/dotnet/orleans/blob/e4e752cedecc2976811db49802c7a999b1f1c704/src/Azure/Orleans.Clustering.Cosmos/HostingExtensions.cs#L47-L49)

```csharp
public static ISiloBuilder UseCosmosClustering(this ISiloBuilder builder)
```

Adds clustering backed by Azure Cosmos DB.

### Parameters

- `builder` (`ISiloBuilder`): The silo builder.

### Returns

The provided `builder`.