An ultra-thin Self-Service Terminals (SSTs) is provided. The ultra-thin SST lacks an Operating System (OS). When the ultra-thin SST is powered on, firmware of the ultra-thin SST connects to a virtualized environment over a first network connection and a Virtual Machine (VM) instance having the OS is loaded within the virtualized environment. The OS of the VM instance obtains middleware services from a second network connection to a middleware environment. The middleware services provided authentication, management, and audit services for the VM instance based on the ultra-thin SST.