diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 0ee8c01..2537c1f 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.3.0"
+  ".": "0.4.0"
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d499966..3a5e2d3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.4.0](https://github.com/cachekit-io/cachekit-core/compare/cachekit-core-v0.3.0...cachekit-core-v0.4.0) (2026-07-27)
+
+
+### Features
+
+* emit StorageEnvelope compressed_data as msgpack bin (protocol 1.1) (LAB-866) ([#59](https://github.com/cachekit-io/cachekit-core/issues/59)) ([c691087](https://github.com/cachekit-io/cachekit-core/commit/c69108763dea380f9768b23b885dca2e73bae51d))
+
 ## [0.3.0](https://github.com/cachekit-io/cachekit-core/compare/cachekit-core-v0.2.1...cachekit-core-v0.3.0) (2026-07-15)
 
 
diff --git a/Cargo.lock b/Cargo.lock
index 8e19558..bad173f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -175,7 +175,7 @@ checksum = "1e748733b7cbc798e1434b6ac524f0c1ff2ab456fe201501e6497c8417a4fc33"
 
 [[package]]
 name = "cachekit-core"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "aes",
  "aes-gcm",
diff --git a/Cargo.toml b/Cargo.toml
index bf9a2c6..9137931 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cachekit-core"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 authors = ["cachekit Contributors"]
 description = "LZ4 compression, xxHash3 integrity, AES-256-GCM encryption for byte payloads"