import modules ; local dll-suffix = so ; if [ modules.peek : OS ] in CYGWIN NT { if $toolset = gcc { dll-suffix = dll ; } else { dll-suffix = lib ; } } if $toolset = darwin { dll-suffix = dylib ; } project ext ; lib a : : bin/$toolset/debug/a.$(dll-suffix) debug : : debug ; lib a : : bin/$toolset/release/a.$(dll-suffix) release : : release ;