Top 20 NuGet pubsub Packages

WampSharp HttpListener based WebSockets support
WampSharp ASP.NET WebSockets support
A common interface for abstracting the Pub/Sub pattern from its concrete implementation.
A BRhodium fork of High performance Redis client, incorporating both synchronous and asynchronous usage. The project did not release an update for long time but made code significat fixes. We will maintain this until the official next version is released above 1.2.6.
.Net SDK to connect ForInvest Pubsub Server
C# Redis Client for the worlds fastest distributed NoSQL datastore. Byte[], String and POCO Typed clients. Thread-Safe Basic and Pooled client managers included.
Mospel MQTT library allows you to build your own MQTT server, giving you the ability to intercept authentication and authorization and much more stuff, currently it only works with WebSocket, later I will add support for TCP socket and TLS connection.
Publisher-subscriber (pub/sub) pattern implementation
Adding PubSub support to WebJob
.NET Standard 2.0 version of ServiceStack.Redis
Bellight MessageBus Amqp
A .NET Core project template optimized for handling GCP PubSub Events.
WampSharp Newtonsoft.Json.Cbor support