Node is designed for high-concurrency environments, where many clients connecting simultaneously can have their needs met quickly and predictably. This ability also implies that each client can expect a Node server to respond rapidly when it itself sends many simultaneous requests.
One of Path's key design beliefs is that keeping state synchronized across clients and servers is complex and difficult to do well. For this reason, applications built with Path exchange data between clients and servers exclusively through the WebSockets protocol.
The following is a high-level view of how Path handles client requests. We see how the cluster module is used to share responsibility for handling socket connections among several socket servers:
Once a request has been assigned to a server that request must be fulfilled. We will call that a transaction. Each transaction is being fulfilled for a single user and, as such, fulfillment is delegated to a user object. This user object is a state machine, containing any specific state information for this user. Depending on transaction fulfillment requirements, one or more actors will be assigned, emitting their results (or error warnings). Authenticated users will have a unique machine to process their requests, while other users will share a common "guest" machine.
In this way each request can be framed within a user scope, accurately resolved within the canonical state and responded to with confidence.