diff --git a/Cargo.toml b/Cargo.toml
index fe9b1c4..e927e35 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name    = "merkle"
-version = "1.9.0"
+version = "1.9.1-pre"
 authors = [
   "Frederic Jacobs <me@fredericjacobs.com>",
   "Dylan Bourgeois <dtsbourg@gmail.com>",