This is a pure .NET RTMP server implementation written in C# with async support.
Tested with one publisher and 50 player in high performance mode on CPU AMD Ryzen Threadripper 3970X 32-Core Processor, CPU usage 90%.
Tested with one publisher and 500 player in low power mode on CPU AMD Ryzen Threadripper 3970X 32-Core Processor, CPU usage 20%.
var server = new RtmpServer();
server.RegisterApp("MyAppName");
server.Start();
Then you can use rtmp://Your domain or ip/MyAppName/StreamName to push and pull the rtmp stream.