Lightweight Message Bus

MessageBus.cs

using namespace System.Threading.Channels;

public class MessageBus<T>
{
    private readonly Channel<T> channel = Channel.CreateUnbounded<T>();

    public void Subscribe(Action<T> handler)
    {
        var reader = channel.Reader;
        Task.Run(async () =>
        {
            while (await reader.WaitToReadAsync())
            {
                while (reader.TryRead(out var item))
                {
                    handler(item);
                }
            }
        });
    }

    public async Task PublishAsync(T message)
    {
        await channel.Writer.WriteAsync(message);
    }
}