diff --git a/hashids.janet b/hashids.janet
index e5284d9..78a87d1 100644
--- a/hashids.janet
+++ b/hashids.janet
@@ -20,7 +20,7 @@
       (var p 0)
 
       (loop [i :down [(- (length alph-bytes) 1) 0]]
-        (let [v (mod i (length salt-bytes))
+        (let [v (mod (- (length alph-bytes) i 1) (length salt-bytes))
               n (get salt-bytes v)]
           (set p (+ p n))
           (def j (mod (+ n v p) i))
diff --git a/test/consistent-shuffle.janet b/test/consistent-shuffle.janet
index 647394e..0781104 100644
--- a/test/consistent-shuffle.janet
+++ b/test/consistent-shuffle.janet
@@ -14,5 +14,13 @@
 (assert
   (= "cadb" (h/consistent-shuffle "abcd" salt)))
 
+(assert
+  (= "f17a8zvCwo0iuqYDXlJ4RmAS2end5ghTcpjbOWLK9GFyE6xUI3ZBMQtPsNHrkV"
+     (h/consistent-shuffle "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890"
+                           "salt")))
+
+
+
 
 
+  
\ No newline at end of file