These implement fluids, or boxes for for thread-local values. They do not require threads to be made with bt:make-thread. The implementation assumes that the value answered by `current-thread' is EQL to the live values of past and future invocations within a particular thread. They also include a LIFT fix. -- I write stuff at http://failex.blogspot.com/ now. But the post formatter and themes are terrible for sharing code, the primary content, so it might go away sooner or later.