1. A computer-readable storage medium comprising computer-executable instructions for executing processes across multiple execution environments, the computer-executable instructions comprising instructions for: maintaining a memory invariance between a requesting process, hosted by a first hosting process and executing in a first execution environment, and a shadow process hosted by a second hosting process executing in a second execution environment, the shadow process being associated with the requesting process, the memory invariance comprising implementation of virtual memory addresses assigned to at least a portion of the requesting process and at least a portion of the shadow process, wherein the virtual memory addressing maps to a same physical memory such that both the process and its shadow utilize identical virtual memory that maps to a same region of physical memory; receiving, in the first execution environment, a first request from the requesting process, the first request associated with one or more functions excluded from the first hosting process but supported by the second hosting process; communicating the first request to the second execution environment; and initiating, in the second execution environment, a second request, equivalent to the first request, from the shadow process to the second hosting process, the second request generated based at least in part on translation of the first request after interception of the first request in the first execution environment.