diff --git a/CHANGELOG.md b/CHANGELOG.md
index c0be33c..3abf846 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,6 @@
 # Changelog
 
-## v0.4.0 - Unreleased
+## v0.4.0 - 2022-02-05
 
 - The `decode_bits` function has been added.
 
diff --git a/gleam.toml b/gleam.toml
index 3642e3a..25531d1 100644
--- a/gleam.toml
+++ b/gleam.toml
@@ -1,5 +1,5 @@
 name = "gleam_json"
-version = "0.3.0"
+version = "0.4.0"
 licences = ["Apache-2.0"]
 description = "Work with JSON in Gleam"