1. A non-transitory computer-readable storage medium for storing instructions that, when executed on a computing device, cause the computing device to: identify a portion of a first stand-alone model in a graphical modeling environment; process the portion of the first stand-alone model to produce first instructions for the portion of the first stand-alone model, the first instructions are used for executing the portion of the first stand-alone model; hold the first instructions in a repository; compare the portion of the first stand-alone model with a portion of a second stand-alone model; determine, based on the comparing, that the portion of the first stand-alone model and the portion of the second stand-alone model are equivalent; and produce second instructions for the portion of the second stand-alone model, where: the second instructions are used for executing the portion of the second stand-alone model, the producing includes: reusing the first instructions as the second instructions based on the determining.