diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a284523..216511e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,6 +10,9 @@ on:
 env:
   CARGO_TERM_COLOR: 'always'
 
+permissions:
+  contents: read
+
 jobs:
   test:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/docker-build.yaml b/.github/workflows/docker-build.yaml
index 007653d..d1e445b 100644
--- a/.github/workflows/docker-build.yaml
+++ b/.github/workflows/docker-build.yaml
@@ -2,56 +2,159 @@ name: Docker Image Build
 
 on:
   pull_request:
-    types:
-      - opened
-      - reopened
-      - synchronize
-      - closed
+  push:
+    branches:
+      - main
+  release:
+    types: [published]
+  workflow_dispatch:
 
 env:
-  REGISTRY: quay.io
-  IMAGE: quay.io/stackmon/metrics-processor
+  REGISTRY: swr.eu-de.otc.t-systems.com
+  PROJECT: metrics-processor
+  # OTC project of the region, listed under "My Credentials > API Credentials" in the OTC console.
+  SWR_PROJECT: eu-de
+
+permissions:
+  contents: read
 
 jobs:
+
   build:
-    if: github.event.pull_request.merged != true
+    if: github.event_name == 'pull_request'
     runs-on: ubuntu-latest
+    env:
+      ORG: stackmon-preprod
 
     steps:
-      - uses: actions/checkout@v7
+    - uses: actions/checkout@v7
+
+    - name: Docker meta
+      id: meta
+      uses: docker/metadata-action@v5
+      with:
+        images: |
+          ${{ env.REGISTRY }}/${{ env.ORG }}/${{ env.PROJECT }}
+        tags: |
+          type=ref,event=pr
 
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
 
-      - name: Build image
-        uses: docker/build-push-action@v7
-        with:
-          context: .
-          target: metrics-processor
-          push: false
+    - name: Build
+      uses: docker/build-push-action@v7
+      with:
+        context: .
+        target: metrics-processor
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+        push: false
 
-  push_if_merged:
-    # The tag is pinned by stackmon-config/config.yaml, keep change_<pr>_latest.
-    if: github.event.pull_request.merged == true
+  # Builds from main and manual runs land in the preprod project; only a release reaches stackmon.
+  publish-preprod:
+    if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
     runs-on: ubuntu-latest
+    env:
+      ORG: stackmon-preprod
 
     steps:
-      - uses: actions/checkout@v7
-
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
-
-      - name: Login to Container Registry
-        uses: docker/login-action@v4
-        with:
-          registry: ${{ env.REGISTRY }}
-          username: ${{ secrets.REGISTRY_USER }}
-          password: ${{ secrets.REGISTRY_PASSWORD }}
-
-      - name: Build and push
-        uses: docker/build-push-action@v7
-        with:
-          context: .
-          target: metrics-processor
-          push: true
-          tags: ${{ env.IMAGE }}:change_${{ github.event.pull_request.number }}_latest
+    - uses: actions/checkout@v7
+
+    - name: Docker meta
+      id: meta
+      uses: docker/metadata-action@v5
+      with:
+        images: |
+          ${{ env.REGISTRY }}/${{ env.ORG }}/${{ env.PROJECT }}
+        tags: |
+          type=sha
+
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+
+    - name: Login to Container Registry
+      env:
+        SWR_AK: ${{ secrets.SWR_PREPROD_AK }}
+        SWR_SK: ${{ secrets.SWR_PREPROD_SK }}
+      run: |
+        set -euo pipefail
+
+        if [ -z "$SWR_AK" ] || [ -z "$SWR_SK" ]; then
+          echo "The SWR_PREPROD_AK and SWR_PREPROD_SK repository secrets must be set" >&2
+          exit 1
+        fi
+
+        # SWR authenticates with "<project>@<AK>" and a login key derived from the AK/SK pair.
+        login_key="$(printf '%s' "$SWR_AK" | openssl dgst -sha256 -hmac "$SWR_SK" | awk '{print $NF}')"
+        if [[ ! "$login_key" =~ ^[0-9a-f]{64}$ ]]; then
+          echo "Cannot derive the SWR login key from the AK/SK pair" >&2
+          exit 1
+        fi
+
+        printf '%s' "$login_key" | docker login "$REGISTRY" --username "${SWR_PROJECT}@${SWR_AK}" --password-stdin
+
+    - name: Build and push
+      uses: docker/build-push-action@v7
+      with:
+        context: .
+        target: metrics-processor
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+        # SWR rejects the OCI image index and attestation manifests that BuildKit adds by default.
+        provenance: false
+        sbom: false
+        push: true
+
+  publish:
+    if: github.event_name == 'release'
+    runs-on: ubuntu-latest
+    env:
+      ORG: stackmon
+
+    steps:
+    - uses: actions/checkout@v7
+
+    - name: Docker meta
+      id: meta
+      uses: docker/metadata-action@v5
+      with:
+        images: |
+          ${{ env.REGISTRY }}/${{ env.ORG }}/${{ env.PROJECT }}
+        tags: |
+          type=semver,pattern=v{{version}}
+
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+
+    - name: Login to Container Registry
+      env:
+        SWR_AK: ${{ secrets.SWR_AK }}
+        SWR_SK: ${{ secrets.SWR_SK }}
+      run: |
+        set -euo pipefail
+
+        if [ -z "$SWR_AK" ] || [ -z "$SWR_SK" ]; then
+          echo "The SWR_AK and SWR_SK repository secrets must be set" >&2
+          exit 1
+        fi
+
+        # SWR authenticates with "<project>@<AK>" and a login key derived from the AK/SK pair.
+        login_key="$(printf '%s' "$SWR_AK" | openssl dgst -sha256 -hmac "$SWR_SK" | awk '{print $NF}')"
+        if [[ ! "$login_key" =~ ^[0-9a-f]{64}$ ]]; then
+          echo "Cannot derive the SWR login key from the AK/SK pair" >&2
+          exit 1
+        fi
+
+        printf '%s' "$login_key" | docker login "$REGISTRY" --username "${SWR_PROJECT}@${SWR_AK}" --password-stdin
+
+    - name: Build and push
+      uses: docker/build-push-action@v7
+      with:
+        context: .
+        target: metrics-processor
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+        # SWR rejects the OCI image index and attestation manifests that BuildKit adds by default.
+        provenance: false
+        sbom: false
+        push: true