diff --git a/Project.toml b/Project.toml
index 7ea025b..6304d92 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "Quantics"
 uuid = "87f76fb3-a40a-40c9-a63c-29fcfe7b7547"
 authors = ["Hiroshi Shinaoka <h.shinaoka@gmail.com> and contributors"]
-version = "0.3.9"
+version = "0.4.0"
 
 [deps]
 EllipsisNotation = "da5c29d0-fa7d-589e-88eb-ea29b0a81949"