I tried fib both ways in vanilla KCl and got the following: > (time (fib 29)) real time : 33.983 secs run time : 31.600 secs 514229 > (time (slow-fib 29)) real time : 32.950 secs run time : 31.583 secs 514229 Repeating the tests got me the same results: it was faster WITHOUT declarations. Ok, I'm convinced -- I'm dropping work to build AKCl. -Eliot