1. A system for static compilation of application code, the system comprising: a data store that operates to store application code comprising a plurality of code regions and to store a plurality of machine models that each models capabilities of a corresponding target platform; a computer-implemented code profiler that operates to identify hot code regions from the plurality of code regions of the application code, such that each hot code region is a primary contributor to runtime execution of the application code; and a computer-implemented code versioner that operates, for each hot code region, to: compile a first version of the hot code region according to a first of the machine models, the first version having a first estimated execution time; compile a second version of the hot code region according to a second of the machine models, the second version having a second estimated execution time; and compile the application code to include both the first and the second versions of the hot code region when a difference between the first and second estimated execution times is greater than a predetermined threshold, the application code being compiled in such a way that permits selection by a target machine at load time between the first and second versions of the hot code region.