diff --git a/Cargo.toml b/Cargo.toml
index 7ed9513..a8e0b42 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "duration-str"
-version = "0.9.0"
+version = "0.9.0-pre"
 authors = ["baoyachi <liaoymxsdl@gmail.com>"]
 edition = "2021"
 description = "duration string parser"