CSRakowski.AsyncStreamsPreparations
Quick helper library containing interfaces and classes to help you prepare for the C# 8 Async Streams feature.
Available on NuGet: 
Contained in this library are the interfaces: IAsyncDisposable, IAsyncEnumerable<T>, IAsyncEnumerator<T> and an AsyncEnumerable<T> helper class that simply wraps a regular IEnumerable<T>.
All interface definitions were taken from the CoreClr and CoreFX GitHub repositories on 2019-02-24. Due to the consolidation efforts of the .NET Team, these have now moved to the Runtime repository.