1. A program for producing a memory image file for an embedded computer that may execute an application program developed on a development computer system to run on a standard full featured operating system, where the application program makes standard operating system calls, the embedded computer having less memory and fewer hardware components than the development computer system and being unable to support the standard full featured operating system, the program comprising: a) a modular operating system mirroring the functions of the full-featured operating system in a plurality of source code operating system modules invokable by the operating system calls from the application program, the source code operating system modules including those providing functions required to interface an application program to the hardware components; b) a scanner program receiving the application program and scanning it for the operating system calls to the full-featured operating system to produce list of the source code operating system modules required by the application program when run on the embedded computer; and c) a compiler compiling the application program and the source code operating system modules on the list, together, to produce a memory image file that fits within the limited memory of the embedded computer that provides a sufficient operating system less than the full featured operating system for the application program invokable by standard operating system calls.