1. A computer-implemented method for securely loading application program code in an application hosting service comprising: installing an application on the application hosting service; generating a process/thread map of processes/threads included in the application, the map including an identification of each process/thread and the hierarchical relationships between the processes/threads; receiving a request to execute processes/threads of an application; comparing the processes/threads to be executed with the process map to determine whether each process/thread to be executed is included in the map and that each process/thread is to be executed at a correct position in the hierarchy; and executing the processes/threads of the application if the processes/threads to be executed are found within the process/thread map at a correct position in the hierarchy specified in the process/thread map; and if the processes/threads to be executed are not found within the process/thread map at a correct position in the hierarchy specified in the process/thread map, then refraining from executing the application.