diff --git a/util.go b/util.go
index 5522a39..9d85bce 100644
--- a/util.go
+++ b/util.go
@@ -2,8 +2,15 @@ package main
 
 import (
 	"math/rand"
+	"time"
 )
 
+var random *rand.Rand
+
+func init() {
+	random = rand.New(rand.NewSource(time.Now().UnixNano()))
+}
+
 const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
 
 func RandStringBytes(n int) string {