diff --git a/beautiful-racket/br/demo/hdl/Nand.hdl.rkt b/beautiful-racket/br/demo/hdl/Nand.hdl.rkt
index 40b2504..8655fa2 100644
--- a/beautiful-racket/br/demo/hdl/Nand.hdl.rkt
+++ b/beautiful-racket/br/demo/hdl/Nand.hdl.rkt
@@ -1,28 +1,13 @@
 #lang br
 
-(define Nand-a
-  (let ([Nand-a-val 0])
-    (λ ([val #f])
-      (if val
-          (set! Nand-a-val val)
-          Nand-a-val))))
-
-(define Nand-b
-  (let ([Nand-b-val 0])
-    (λ ([val #f])
-      (if val
-          (set! Nand-b-val val)
-          Nand-b-val))))
-
-
-(define (Nand-out)
-  (if (< (+ (Nand-a) (Nand-b)) 2)
+(define+provide (Nand #:a a #:b b)
+  (if (< (+ a b) 2)
       1
       0))
 
 (module+ test
   (require rackunit)
-  (check-equal? (begin (Nand-a 0) (Nand-b 0) (Nand-out)) 1)
-  (check-equal? (begin (Nand-a 0) (Nand-b 1) (Nand-out)) 1)
-  (check-equal? (begin (Nand-a 1) (Nand-b 0) (Nand-out)) 1)
-  (check-equal? (begin (Nand-a 1) (Nand-b 1) (Nand-out)) 0))
+  (check-equal? (Nand #:a 0 #:b 0) 1)
+  (check-equal? (Nand #:a 0 #:b 1) 1)
+  (check-equal? (Nand #:a 1 #:b 0) 1)
+  (check-equal? (Nand #:a 1 #:b 1) 0))
diff --git a/beautiful-racket/br/demo/hdl/Nand2.hdl.rkt b/beautiful-racket/br/demo/hdl/Nand2.hdl.rkt
new file mode 100644
index 0000000..139d2db
--- /dev/null
+++ b/beautiful-racket/br/demo/hdl/Nand2.hdl.rkt
@@ -0,0 +1,36 @@
+#lang br
+
+(define Nand-in-a
+  (let ([Nand-a-val 0])
+    (λ ([val #f])
+      (if val
+          (set! Nand-a-val val)
+          Nand-a-val))))
+
+(define Nand-in-b
+  (let ([Nand-b-val 0])
+    (λ ([val #f])
+      (if val
+          (set! Nand-b-val val)
+          Nand-b-val))))
+
+
+(define (Nand-out-out)
+  (if (< (+ (Nand-in-a) (Nand-in-b)) 2)
+      1
+      0))
+
+(module+ test
+  (require rackunit)
+  (check-equal? (begin (Nand-in-a 0) (Nand-in-b 0) (Nand-out-out)) 1)
+  (check-equal? (begin (Nand-in-a 0) (Nand-in-b 1) (Nand-out-out)) 1)
+  (check-equal? (begin (Nand-in-a 1) (Nand-in-b 0) (Nand-out-out)) 1)
+  (check-equal? (begin (Nand-in-a 1) (Nand-in-b 1) (Nand-out-out)) 0))
+
+
+(struct ins ([a #:auto] [b #:auto]) #:transparent
+  #:auto-value (open-input-bytes #""))
+(struct outs ([out #:auto]) #:transparent)
+(struct Nand (i o) #:transparent)
+
+(define f (Nand (ins) (outs)))
\ No newline at end of file