A system and method for performing speculative initialization of application models for a cloned runtime system process is presented. A class loader is created for each application model. Each such class loader includes a representation of at least one class from a source definition provided as object-oriented program code and associated with the application model. A master runtime system process is executed. The representation of the class loader is interpreted, instantiated and warmed up as an application model specific class loader instance in a memory space of the master runtime system process. The memory space is cloned as a child runtime system process responsive to a process request and the child runtime system process is executed. The child runtime process selects one such application model specific class loader instance, rather than creating a new application model specific class loader instance.