diff --git a/CHANGELOG.md b/CHANGELOG.md
index e26567a8..66d6571f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## mdBook 0.4.0
+[99ecd4f...HEAD](https://github.com/rust-lang/mdBook/compare/99ecd4f...HEAD)
+
+
 ## mdBook 0.3.7
 [88684d8...99ecd4f](https://github.com/rust-lang/mdBook/compare/88684d8...99ecd4f)
 
diff --git a/Cargo.lock b/Cargo.lock
index 1fdcba81..f48ba9ab 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -666,7 +666,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "mdbook"
-version = "0.3.7"
+version = "0.4.0"
 dependencies = [
  "ammonia 3.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "chrono 0.4.9 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/Cargo.toml b/Cargo.toml
index a774a57e..b45c7a0f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "mdbook"
-version = "0.3.7"
+version = "0.4.0"
 authors = [
     "Mathieu David <mathieudavid@mathieudavid.org>",
     "Michael-F-Bryan <michaelfbryan@gmail.com>",