Put the architecture name into the Makefile explicitly.
Ignore the lib directory.
Add a generic makefile that can call the arch specific version (for
cleaning, etc.).
Rename the tests/ Makefile to be arch specific.
Add a generic Makefile that will call the arch specific Makefile.
Add a top-level Makefile.
Move the setup script (for LD_LIB path stuff) to the top level so nobody
needs to look for it.
Put the test exe in a bin directory.
Modify ld/dyld path based on architecture.
Update the documentation (as it were).