# ILifecycleObserver

Package: [Microsoft.Orleans.Core.Abstractions](/orleans/docs/api/csharp/microsoft.orleans.core.abstractions/) 10.0.0

[NuGet package](https://www.nuget.org/packages/Microsoft.Orleans.Core.Abstractions)

```csharp
public interface ILifecycleObserver
```

Lifecycle observer used to handle start and stop notification.

## Methods

- [OnStart(CancellationToken)](/orleans/docs/api/csharp/microsoft.orleans.core.abstractions/orleans.ilifecycleobserver/methods/onstart-system-threading-cancellationtoken-e37834d3/)
- [OnStop(CancellationToken)](/orleans/docs/api/csharp/microsoft.orleans.core.abstractions/orleans.ilifecycleobserver/methods/onstop-system-threading-cancellationtoken-665728bd/)