A virtual execution system that is configured to be used in a resource-constrained device. The resource-constrained device includes an operating system and an application program that includes instructions. The virtual execution system includes an execution engine that is configured to execute the application program, and to facilitate the compatibility of the application program with the operating system. Non-functional aspects characterize the instructions and the operating system. The execution engine has access to the non-functional aspects, and implements improvements during the execution of the application program based on the non-functional aspects.