diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09e630e..ce35164 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,6 @@
 # Changelog
 
-## Unreleased
+## v1.4.0 - 2023-08-29
 
 - Shellout now requires Gleam v0.30 or later.
 - Shellout no longer depends on `gleam_erlang`.
diff --git a/README.md b/README.md
index f712a5f..2e0a14a 100644
--- a/README.md
+++ b/README.md
@@ -83,7 +83,7 @@ pub fn main() {
 
 ```toml
 [dependencies]
-shellout = "~> 1.3"
+shellout = "~> 1.4"
 ```
 
 ### As a dependency of your Mix project
@@ -93,7 +93,7 @@ shellout = "~> 1.3"
 ```elixir
 defp deps do
   [
-    {:shellout, "~> 1.3"},
+    {:shellout, "~> 1.4"},
   ]
 end
 ```
@@ -104,6 +104,6 @@ end
 
 ```erlang
 {deps, [
-  {shellout, "1.3.0"}
+  {shellout, "1.4.0"}
 ]}.
 ```
diff --git a/gleam.toml b/gleam.toml
index 523ee0c..bc4c249 100644
--- a/gleam.toml
+++ b/gleam.toml
@@ -1,5 +1,5 @@
 name = "shellout"
-version = "1.4.0-dev"
+version = "1.4.0"
 description = "A Gleam library for cross-platform shell operations"
 licences = ["Apache-2.0"]
 gleam = "~> 0.30"