1. A method of configuring a server having a processor and a network address to execute at least two instances of an application on behalf of a user of a device accessible over a network through a routing table, the method comprising: executing on the processor instructions configured to: responsive to receiving the application: store the application; and allocate at least two subdomains of the server for respective instances of the application, where the at least two subdomains are mapped to the network address of the server through one routing rule in the routing table; and responsive to receiving a request to execute the application on behalf of the user: among the at least two subdomains allocated for the respective instances of the application, select a selected subdomain that has not been selected for another instance of the application; instantiating a new instance of the application on the processor; and serve an application user interface of the new instance of the application to the device of the user through the selected subdomain serving the application user interface of the application.