diff --git a/test-foreign.scm b/test-foreign.scm
index ebf5d46e..9185c5d1 100644
--- a/test-foreign.scm
+++ b/test-foreign.scm
@@ -15,43 +15,53 @@
         (cdr expr))
       `(Cyc-foreign-code ,@(cdr expr)))))
 
-(pretty-print
-(
-;(define-syntax define-foreign-code
-;  (er-macro-transformer
+;(pretty-print
+;(
+(define-syntax define-foreign-code
+  (er-macro-transformer
     (lambda (expr rename compare)
       (let* ((scm-fnc (cadr expr))
              (c-fnc (cadddr expr))
              (rv-type (caddr expr))
              (arg-types (cddddr expr))
-             (arg-syms 
+             (arg-syms/unbox 
                (map 
                  (lambda (type)
-                   (mangle (gensym type)))
+                   (let ((var (mangle (gensym 'arg))))
+                     (cons var (string-append "string_str(" var ")"))))
                  arg-types))
-             (arg-strings 
-               (map
-                 (lambda (sym)
-                   (string-append " object " sym) 
-                 )
-                 arg-syms))
+             ;(arg-strings 
+             ;  (map
+             ;    (lambda (sym)
+             ;      (string-append " object " sym) 
+             ;    )
+             ;    arg-syms))
 
            ; TODO: append mangled args to other args
            ;  cyclone> (string-join '("a" "b" "c") ",")
            ;  "a,b,c"
 
-             (args "(void *data, int argc, closure _, object k)")
+             (args (string-append
+                     "(void *data, int argc, closure _, object k " 
+                     (apply string-append 
+                       (map
+                         (lambda (sym/unbox)
+                           (string-append "," (car sym/unbox)))
+                       arg-syms/unbox))
+                      ")"))
              (body
              ;; TODO: need to unbox all args, pass to C function, then box up the result
                (string-append
-                 "return_closcall1(data, k, obj_int2obj(" "str" "));"))
+                 "return_closcall1(data, k, obj_int2obj(" c-fnc "(" (string-join (map cdr arg-syms/unbox) ",") ")));"))
             )
       `((define-c ,scm-fnc ,args ,body)
         )))
- '(define-foreign-lambda scm-strlen int "strlen" string dummy dummy)
- list
- list)
+; '(define-foreign-lambda scm-strlen int "strlen" string)
+; list
+; list)
 )
+(define-foreign-lambda scm-strlen int "strlen" string)
+(display (scm-strlen "testing 1, 2, 3"))
 (newline)
 
 ;(define-c foreign-value