Abstract: A development system of the present invention includes a compiler, a linker, and an interface. The compiler serves to compile source listings into object modules (which are initially stored in .OBJ files). A librarian is provided for combining desired ones of the .OBJ files into one or more library files. For each library file, the librarian provides an Extended Dictionary of the present invention, which includes a Dependency List and an Unresolved Externals List for each module of the library. Methods are described for linking object modules from .OBJ files and library files, where library object modules which are not needed for the link may be determined before the libraries are scanned during the first pass of the linker. In this manner, library object modules which are not needed during subsequent linking operations can be skipped.