This invention discloses a software development system that includes a user input device, a compiler, a build microprocessor and a data storage. The data storage stores a built program built by the build microprocessor by packaging a plurality of heterogeneous program units comprises at least a binary program-unit processed by the compiler and at least a non-compiled program unit inputted by a user to the built microprocessor through the user input device. The program unit to be compiled into binary program unit and the non-compiled program unit stored in the data storage are programmed by at least two different programming languages.