diff --git a/dex/Cargo.toml b/dex/Cargo.toml
index dafbc26b..469e8542 100644
--- a/dex/Cargo.toml
+++ b/dex/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "serum_dex"
-version = "0.3.1"
+version = "0.4.0"
 description = "Serum DEX"
 repository = "https://github.com/project-serum/serum-dex"
 edition = "2018"