Abstract: Embodiments of apparatus, computer-implemented methods, systems, devices, and computer-readable media are described herein to provide a computing device with cooperative first and second binary translators in first and second execution environments having first and second security levels, respectively. The second security level may be more secure than the first security level. Encrypted instructions of the computer program may be loaded into the first execution environment, and the first binary translator may provide, to the second binary translator, an execution context of the computer program for use by the secondary binary translator to decrypt and execute a first portion of the computer program in the second execution environment. The second binary translator may provide, to the first binary translator, another execution context of the computer program for emulation, by the first binary translator, of execution of a second portion of the computer program in the first execution environment.