diff --git a/CHANGELOG.md b/CHANGELOG.md
index 518850d..4d0eaa2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.4.0] - 2026-09-14
+
 ### Added
 - **Azure Managed Identity Authentication**: Added support for Azure Database for PostgreSQL Flexible Server authentication using Microsoft Entra ID OAuth2 access tokens via Azure Workload Identity, VM-based Managed Identity, and Azure CLI.
 - **Dynamic Token Refresh**: Integrated with `pgxpool.Pool` via `BeforeConnect` to automatically acquire fresh tokens for scope `https://ossrdbms-aad.database.windows.net/.default` on every new connection, and periodically recycle pool connections with configurable `POSTGRES_MAX_CONN_LIFETIME`.
@@ -14,6 +16,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **Decoupled Schema Migrations**: Supported running migrations via Azure Managed Identity, an independently authenticated password DSN (`POSTGRES_MIGRATIONS_DSN`), or skipping startup migrations (`POSTGRES_RUN_MIGRATIONS=false`) for external jobs/pipelines (`POSTGRES_MIGRATE_ONLY=true`).
 - **Helm Chart Azure Workload Identity Support**: Added Helm values and templates for Azure Workload Identity, direct DSNs without static password secrets, and added `values-azure-workload-identity.yaml` example.
 
+### Changed
+- Updated Helm chart version and appVersion to `0.4.0`.
+- Configured default container image in `docker-compose.yml` to `ghcr.io/autonomous-bits/spool-rack:0.4.0`.
+- Updated binary version to `0.4.0`.
+
 ## [0.3.0] - 2026-09-13
 
 ### Added
@@ -50,7 +57,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Seeded development environment with Docker Compose.
 - Health endpoint (`/healthz`) with contract and version diagnostics.
 
-[Unreleased]: https://github.com/autonomous-bits/spool-rack/compare/v0.3.0...HEAD
+[Unreleased]: https://github.com/autonomous-bits/spool-rack/compare/v0.4.0...HEAD
+[0.4.0]: https://github.com/autonomous-bits/spool-rack/compare/v0.3.0...v0.4.0
 [0.3.0]: https://github.com/autonomous-bits/spool-rack/compare/v0.2.0...v0.3.0
 [0.2.0]: https://github.com/autonomous-bits/spool-rack/compare/v0.1.0...v0.2.0
 [0.1.0]: https://github.com/autonomous-bits/spool-rack/releases/tag/v0.1.0
diff --git a/README.md b/README.md
index c4a5eb4..e59ef02 100644
--- a/README.md
+++ b/README.md
@@ -123,7 +123,7 @@ kubectl -n spool-rack create secret generic spool-rack-postgres \
 
 # 2. Install the chart
 helm upgrade --install spool-rack oci://ghcr.io/autonomous-bits/charts/spool-rack \
-  --version 0.3.0 \
+  --version 0.4.0 \
   --namespace spool-rack \
   --set postgres.dsnSecret.name=spool-rack-postgres
 ```
diff --git a/charts/spool-rack/Chart.yaml b/charts/spool-rack/Chart.yaml
index 30a0918..17c7fbc 100644
--- a/charts/spool-rack/Chart.yaml
+++ b/charts/spool-rack/Chart.yaml
@@ -2,8 +2,8 @@ apiVersion: v2
 name: spool-rack
 description: A Helm chart for the Spool Rack server
 type: application
-version: 0.3.0
-appVersion: "0.3.0"
+version: 0.4.0
+appVersion: "0.4.0"
 annotations:
   org.opencontainers.image.source: https://github.com/autonomous-bits/spool-rack
   org.opencontainers.image.description: Helm chart for Spool Rack server
diff --git a/charts/spool-rack/README.md b/charts/spool-rack/README.md
index 7342701..ee5ea28 100644
--- a/charts/spool-rack/README.md
+++ b/charts/spool-rack/README.md
@@ -20,7 +20,7 @@ Install directly from the published OCI registry:
 
 ```bash
 helm upgrade --install spool-rack oci://ghcr.io/autonomous-bits/charts/spool-rack \
-  --version 0.3.0 \
+  --version 0.4.0 \
   --namespace spool-rack \
   --set postgres.dsnSecret.name=spool-rack-postgres
 ```
diff --git a/cmd/spool-rack/main.go b/cmd/spool-rack/main.go
index dbe9743..a559a5a 100644
--- a/cmd/spool-rack/main.go
+++ b/cmd/spool-rack/main.go
@@ -21,7 +21,7 @@ const (
 )
 
 var (
-	version = "0.3.0"
+	version = "0.4.0"
 )
 
 func main() {
diff --git a/cmd/spool-rack/main_test.go b/cmd/spool-rack/main_test.go
index 0bbcc96..dec170f 100644
--- a/cmd/spool-rack/main_test.go
+++ b/cmd/spool-rack/main_test.go
@@ -82,7 +82,7 @@ func TestResolveMigrationUser(t *testing.T) {
 }
 
 func TestVersion(t *testing.T) {
-	if version != "0.3.0" {
-		t.Errorf("version = %q, want 0.3.0", version)
+	if version != "0.4.0" {
+		t.Errorf("version = %q, want 0.4.0", version)
 	}
 }
diff --git a/docker-compose.yml b/docker-compose.yml
index 6ea3ad6..6d5ac2c 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,6 +1,6 @@
 services:
   spool-rack:
-    image: ${SPOOL_RACK_IMAGE:-ghcr.io/autonomous-bits/spool-rack:0.3.0}
+    image: ${SPOOL_RACK_IMAGE:-ghcr.io/autonomous-bits/spool-rack:0.4.0}
     build:
       context: .
       dockerfile: Dockerfile
diff --git a/infra/README.md b/infra/README.md
index f93408e..b1fcc45 100644
--- a/infra/README.md
+++ b/infra/README.md
@@ -43,7 +43,7 @@ kubectl -n spool-rack create secret generic spool-rack-postgres \
 From the published OCI registry:
 ```bash
 helm upgrade --install spool-rack oci://ghcr.io/autonomous-bits/charts/spool-rack \
-  --version 0.3.0 \
+  --version 0.4.0 \
   --namespace spool-rack \
   --set postgres.dsnSecret.name=spool-rack-postgres
 ```
diff --git a/infra/charts/spool-rack/Chart.yaml b/infra/charts/spool-rack/Chart.yaml
index 30a0918..17c7fbc 100644
--- a/infra/charts/spool-rack/Chart.yaml
+++ b/infra/charts/spool-rack/Chart.yaml
@@ -2,8 +2,8 @@ apiVersion: v2
 name: spool-rack
 description: A Helm chart for the Spool Rack server
 type: application
-version: 0.3.0
-appVersion: "0.3.0"
+version: 0.4.0
+appVersion: "0.4.0"
 annotations:
   org.opencontainers.image.source: https://github.com/autonomous-bits/spool-rack
   org.opencontainers.image.description: Helm chart for Spool Rack server
diff --git a/infra/charts/spool-rack/README.md b/infra/charts/spool-rack/README.md
index 7342701..ee5ea28 100644
--- a/infra/charts/spool-rack/README.md
+++ b/infra/charts/spool-rack/README.md
@@ -20,7 +20,7 @@ Install directly from the published OCI registry:
 
 ```bash
 helm upgrade --install spool-rack oci://ghcr.io/autonomous-bits/charts/spool-rack \
-  --version 0.3.0 \
+  --version 0.4.0 \
   --namespace spool-rack \
   --set postgres.dsnSecret.name=spool-rack-postgres
 ```