Pub/sub channels are very cheap. You can have millions of unique channels without worrying about memory or CPU usage. Channels are automatically cleaned up when they are no longer used.

The socketcluster CLI tool exposes kubectl (Kubernetes) shortcut commands to make deploying your app to any Kubernetes cluster really easy. All necessary Kubernetes .yaml files are provided.

After deploying your app to a Kubernetes cluster, you can scale indefinitely by using the kubectl scale deployment command to add more scc-worker and scc-broker instances as needed.

You can perform asynchronous operations anywhere along a socket's inbound or outbound stream without any risk of disrupting the message processing order.

Awaiting for asynchronous actions along a socket's inbound or outbout streams can cause messages to pile up. This can be easily monitored on the back end using socket.getInboundBackpressure() and socket.getOutboundBackpressure().

SocketCluster supports JWT authentication. This form of authentication is ideal for WebSockets because the token expiry can be made arbitrarily short and renewed often on an interval for very little performance cost while saving many database lookups.

Middleware streams allow you to block socket connections using the MIDDLEWARE_HANDSHAKE middleware line and to block individual socket actions using the MIDDLEWARE_INBOUND and MIDDLEWARE_OUTBOUND lines.

Every data packet which is being received from or being sent to a client can be delayed or transformed using MIDDLEWARE_INBOUND_RAW, MIDDLEWARE_INBOUND or MIDDLEWARE_OUTBOUND lines.

All data and events must be consumed using asynchronous loops (e.g. for-await-of). Event listener callbacks are not supported; this solves many problems related to code readability and maintainability.

Clients are optimized to handle lost connections seamlessly. For example, if a client loses the connection, channels attached to that socket will be put in a pending state and automatically resubscribe after the socket reconnects.

Without callbacks, asynchronous logic can always be executed from top to bottom. This makes it more obvious which parts of the code are serial and which parts are parallel and it encourages a more declarative style of programming.

Sockets and channels do not need to be destroyed explicitly. They will be automatically marked for garbage collection as soon as they stop being used and are no longer referenced in the code.