@waflib.TaskGen.feature("stuff")
def do_stuff(self):
   tsk = self.create_task("Compass", self.in_source_node, self.in_target_node)
   tsk.cwd = self.in_source_node.parent.abspath()

class Compass(Task.Task):
    color = 'BLUE'
    run_str = '${COMPASS} compile -c ${SRC[0].abspath()}'

    def scan(self):
        sass_dir = self.inputs[0].parent
        sass_files = sass_dir.ant_glob('**/*.scss')
        return (sass_files, "")

@conf
def compass(bld, source=None, target=None, **kwargs):
    return bld(features="stuff",in_source_node=source,in_target_node=target)