diff --git a/beautiful-racket-demo/stacker-demo/stacker.rkt b/beautiful-racket-demo/stacker-demo/stacker.rkt
index 27fc543..f599279 100644
--- a/beautiful-racket-demo/stacker-demo/stacker.rkt
+++ b/beautiful-racket-demo/stacker-demo/stacker.rkt
@@ -17,12 +17,12 @@
 (define stack empty)
 
 (define (pop-stack!)
-  (define item (first stack))
+  (define arg (first stack))
   (set! stack (rest stack))
-  item)
+  arg)
 
-(define (push-stack! item)
-  (set! stack (cons item stack)))
+(define (push-stack! arg)
+  (set! stack (cons arg stack)))
 
 (define (handle [arg #f])
   (cond
diff --git a/beautiful-racket-demo/stackerizer-demo/stackerizer.rkt b/beautiful-racket-demo/stackerizer-demo/stackerizer.rkt
index e06f134..a150a51 100644
--- a/beautiful-racket-demo/stackerizer-demo/stackerizer.rkt
+++ b/beautiful-racket-demo/stackerizer-demo/stackerizer.rkt
@@ -1,10 +1,9 @@
 #lang br/quicklang
 (provide + *)
 
-(define-macro (stackerizer-mb EXPR ...)
+(define-macro (stackerizer-mb EXPR)
   #'(#%module-begin
-     (for-each displayln
-               (reverse (flatten (list EXPR ...))))))
+     (for-each displayln (reverse (flatten EXPR)))))
 (provide (rename-out [stackerizer-mb #%module-begin]))
 
 (define-macro (define-ops OP ...)