diff --git a/.gitea/workflows/runtime-distribution.yml b/.gitea/workflows/runtime-distribution.yml
new file mode 100644
index 0000000..89c6734
--- /dev/null
+++ b/.gitea/workflows/runtime-distribution.yml
@@ -0,0 +1,243 @@
+name: Runtime Distribution
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: Release version without leading v
+        required: true
+        type: string
+      python_image:
+        description: Digest-pinned multi-architecture Python 3.12 slim image
+        required: true
+        type: string
+      nginx_image:
+        description: Digest-pinned multi-architecture nginx-unprivileged image
+        required: true
+        type: string
+      postgres_image:
+        description: Digest-pinned PostgreSQL image
+        required: true
+        type: string
+      redis_image:
+        description: Digest-pinned Redis image
+        required: true
+        type: string
+      load_balancer_image:
+        description: Digest-pinned HAProxy image
+        required: true
+        type: string
+      garage_image:
+        description: Digest-pinned Garage image
+        required: true
+        type: string
+      test_mail_image:
+        description: Digest-pinned GreenMail image
+        required: true
+        type: string
+
+jobs:
+  publish-runtime:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
+        with:
+          path: govoplan
+      - uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065
+        with:
+          python-version: "3.12"
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020
+        with:
+          node-version: "22"
+      - name: Use HTTPS for GovOPlaN repositories
+        run: |
+          git config --global --add url."https://git.add-ideas.de/GovOPlaN/govoplan".insteadOf "git@git.add-ideas.de:GovOPlaN/govoplan"
+          git config --global --add url."https://git.add-ideas.de/GovOPlaN/govoplan".insteadOf "ssh://git@git.add-ideas.de/GovOPlaN/govoplan"
+      - name: Bootstrap release sources
+        working-directory: govoplan
+        run: python tools/repo/bootstrap-repositories.py --parent .. --transport public-https --exclude-repo addideas-govoplan-website
+      - name: Build release wheel roots and WebUI
+        working-directory: govoplan
+        run: |
+          python -m venv .runtime-build
+          .runtime-build/bin/python -m pip install --upgrade pip wheel cryptography
+          mkdir -p runtime-output/local-wheels
+          .runtime-build/bin/python -m pip wheel --no-deps --wheel-dir runtime-output/local-wheels --requirement requirements-release.txt
+          bash tools/release/install-webui-release-dependencies.sh ../govoplan-core/webui
+          npm --prefix ../govoplan-core/webui run build
+          .runtime-build/bin/python tools/release/prepare-runtime-context.py \
+            --wheelhouse runtime-output/local-wheels \
+            --web-dist ../govoplan-core/webui/dist \
+            --output runtime-output/common \
+            --required-module tenancy \
+            --required-module organizations \
+            --required-module identity \
+            --required-module idm \
+            --required-module access \
+            --required-module admin \
+            --required-module dashboard \
+            --required-module policy \
+            --required-module audit \
+            --required-module docs \
+            --required-module ops
+      - name: Resolve architecture-specific offline wheelhouses
+        working-directory: govoplan
+        run: |
+          mkdir -p runtime-output/wheels-amd64 runtime-output/wheels-arm64
+          cp runtime-output/local-wheels/*.whl runtime-output/wheels-amd64/
+          cp runtime-output/local-wheels/*.whl runtime-output/wheels-arm64/
+          .runtime-build/bin/python -m pip download --only-binary=:all: \
+            --platform manylinux_2_17_x86_64 --platform manylinux2014_x86_64 \
+            --implementation cp --python-version 3.12 --abi cp312 \
+            --find-links runtime-output/local-wheels \
+            --dest runtime-output/wheels-amd64 \
+            --requirement runtime-output/common/requirements-runtime.txt
+          .runtime-build/bin/python -m pip download --only-binary=:all: \
+            --platform manylinux_2_17_aarch64 --platform manylinux2014_aarch64 \
+            --implementation cp --python-version 3.12 --abi cp312 \
+            --find-links runtime-output/local-wheels \
+            --dest runtime-output/wheels-arm64 \
+            --requirement runtime-output/common/requirements-runtime.txt
+          .runtime-build/bin/python tools/release/prepare-runtime-context.py \
+            --wheelhouse runtime-output/wheels-amd64 \
+            --web-dist ../govoplan-core/webui/dist \
+            --output runtime-output/context-amd64
+          .runtime-build/bin/python tools/release/prepare-runtime-context.py \
+            --wheelhouse runtime-output/wheels-arm64 \
+            --web-dist ../govoplan-core/webui/dist \
+            --output runtime-output/context-arm64
+          cmp runtime-output/context-amd64/composition.json runtime-output/context-arm64/composition.json
+      - name: Build one-file deployer
+        working-directory: govoplan
+        run: python tools/deployment/build-deployer-zipapp.py --output runtime-output/govoplan-deploy.pyz
+      - name: Authenticate OCI publication
+        working-directory: govoplan
+        env:
+          REGISTRY_USERNAME: ${{ secrets.GOVOPLAN_REGISTRY_USERNAME }}
+          REGISTRY_TOKEN: ${{ secrets.GOVOPLAN_REGISTRY_TOKEN }}
+        run: |
+          test -n "$REGISTRY_USERNAME"
+          test -n "$REGISTRY_TOKEN"
+          printf '%s' "$REGISTRY_TOKEN" | docker login git.add-ideas.de --username "$REGISTRY_USERNAME" --password-stdin
+          docker buildx create --name govoplan-runtime --use
+      - name: Build and publish architecture images
+        working-directory: govoplan
+        env:
+          VERSION: ${{ inputs.version }}
+          PYTHON_IMAGE: ${{ inputs.python_image }}
+          NGINX_IMAGE: ${{ inputs.nginx_image }}
+        run: |
+          COMPOSITION_SHA256="$(sha256sum runtime-output/context-amd64/composition.json | cut -d' ' -f1)"
+          for ARCH in amd64 arm64; do
+            docker buildx build --platform "linux/$ARCH" --push \
+              --file tools/release/runtime/Dockerfile.api \
+              --build-arg "PYTHON_IMAGE=$PYTHON_IMAGE" \
+              --build-arg "GOVOPLAN_RELEASE_VERSION=$VERSION" \
+              --build-arg "GOVOPLAN_COMPOSITION_SHA256=$COMPOSITION_SHA256" \
+              --tag "git.add-ideas.de/govoplan/runtime-api:$VERSION-$ARCH" \
+              "runtime-output/context-$ARCH"
+            docker buildx build --platform "linux/$ARCH" --push \
+              --file tools/release/runtime/Dockerfile.web \
+              --build-arg "NGINX_IMAGE=$NGINX_IMAGE" \
+              --build-arg "GOVOPLAN_RELEASE_VERSION=$VERSION" \
+              --build-arg "GOVOPLAN_COMPOSITION_SHA256=$COMPOSITION_SHA256" \
+              --tag "git.add-ideas.de/govoplan/runtime-web:$VERSION-$ARCH" \
+              "runtime-output/context-$ARCH"
+          done
+          docker buildx imagetools create \
+            --tag "git.add-ideas.de/govoplan/runtime-api:$VERSION" \
+            "git.add-ideas.de/govoplan/runtime-api:$VERSION-amd64" \
+            "git.add-ideas.de/govoplan/runtime-api:$VERSION-arm64"
+          docker buildx imagetools create \
+            --tag "git.add-ideas.de/govoplan/runtime-web:$VERSION" \
+            "git.add-ideas.de/govoplan/runtime-web:$VERSION-amd64" \
+            "git.add-ideas.de/govoplan/runtime-web:$VERSION-arm64"
+          docker buildx imagetools inspect "git.add-ideas.de/govoplan/runtime-api:$VERSION" --raw > runtime-output/api-index.json
+          docker buildx imagetools inspect "git.add-ideas.de/govoplan/runtime-web:$VERSION" --raw > runtime-output/web-index.json
+          API_DIGEST="sha256:$(sha256sum runtime-output/api-index.json | cut -d' ' -f1)"
+          WEB_DIGEST="sha256:$(sha256sum runtime-output/web-index.json | cut -d' ' -f1)"
+          python tools/release/resolve-oci-platforms.py --repository git.add-ideas.de/govoplan/runtime-api --index-digest "$API_DIGEST" --index runtime-output/api-index.json --output runtime-output/api-metadata.json
+          python tools/release/resolve-oci-platforms.py --repository git.add-ideas.de/govoplan/runtime-web --index-digest "$WEB_DIGEST" --index runtime-output/web-index.json --output runtime-output/web-metadata.json
+      - name: Generate and sign distribution evidence
+        working-directory: govoplan
+        env:
+          VERSION: ${{ inputs.version }}
+          SOURCE_COMMIT: ${{ gitea.sha }}
+          SIGNING_KEY: ${{ secrets.RUNTIME_DISTRIBUTION_SIGNING_KEY }}
+          SIGNING_KEY_ID: ${{ secrets.RUNTIME_DISTRIBUTION_SIGNING_KEY_ID }}
+          TRUSTED_KEYRING: ${{ secrets.RUNTIME_DISTRIBUTION_KEYRING }}
+          POSTGRES_IMAGE: ${{ inputs.postgres_image }}
+          REDIS_IMAGE: ${{ inputs.redis_image }}
+          LOAD_BALANCER_IMAGE: ${{ inputs.load_balancer_image }}
+          GARAGE_IMAGE: ${{ inputs.garage_image }}
+          TEST_MAIL_IMAGE: ${{ inputs.test_mail_image }}
+        run: |
+          test -n "$SIGNING_KEY"
+          test -n "$SIGNING_KEY_ID"
+          test -n "$TRUSTED_KEYRING"
+          printf '%s\n' "$SIGNING_KEY" > runtime-output/signing-key.pem
+          printf '%s\n' "$TRUSTED_KEYRING" > runtime-output/distribution-keyring.json
+          chmod 600 runtime-output/signing-key.pem
+          ARTIFACT_BASE="https://git.add-ideas.de/GovOPlaN/govoplan/releases/download/v$VERSION"
+          python tools/release/finalize-runtime-distribution.py \
+            --composition runtime-output/context-amd64/composition.json \
+            --api-metadata runtime-output/api-metadata.json \
+            --web-metadata runtime-output/web-metadata.json \
+            --deployer runtime-output/govoplan-deploy.pyz \
+            --deployer-url "$ARTIFACT_BASE/govoplan-deploy.pyz" \
+            --artifact-base-url "$ARTIFACT_BASE" \
+            --source-commit "$SOURCE_COMMIT" \
+            --version "$VERSION" \
+            --sequence "$(date -u +%Y%m%d%H%M)" \
+            --dependency "postgres=$POSTGRES_IMAGE" \
+            --dependency "redis=$REDIS_IMAGE" \
+            --dependency "load_balancer=$LOAD_BALANCER_IMAGE" \
+            --dependency "garage=$GARAGE_IMAGE" \
+            --dependency "test_mail=$TEST_MAIL_IMAGE" \
+            --output-directory runtime-output/evidence \
+            --descriptor runtime-output/distribution-descriptor.json
+          python tools/release/generate-runtime-distribution.py \
+            --descriptor runtime-output/distribution-descriptor.json \
+            --signing-key "$SIGNING_KEY_ID=runtime-output/signing-key.pem" \
+            --output runtime-output/distribution-manifest.json
+          openssl pkeyutl -sign -inkey runtime-output/signing-key.pem -rawin \
+            -in runtime-output/govoplan-deploy.pyz \
+            -out runtime-output/govoplan-deploy.pyz.sig
+          sha256sum runtime-output/govoplan-deploy.pyz > runtime-output/govoplan-deploy.pyz.sha256
+          sha256sum runtime-output/distribution-manifest.json > runtime-output/distribution-manifest.json.sha256
+          rm runtime-output/signing-key.pem
+      - name: Verify the published bundle contract with the zipapp
+        working-directory: govoplan
+        env:
+          VERSION: ${{ inputs.version }}
+        run: |
+          MANIFEST_SHA256="$(cut -d' ' -f1 runtime-output/distribution-manifest.json.sha256)"
+          python runtime-output/govoplan-deploy.pyz init \
+            --directory runtime-output/acceptance-install \
+            --non-interactive --module-set base
+          python runtime-output/govoplan-deploy.pyz verify-release \
+            --directory runtime-output/acceptance-install \
+            --manifest runtime-output/distribution-manifest.json \
+            --manifest-sha256 "$MANIFEST_SHA256" \
+            --trusted-keyring runtime-output/distribution-keyring.json \
+            --adopt
+      - name: Publish immutable Gitea release assets
+        working-directory: govoplan
+        env:
+          VERSION: ${{ inputs.version }}
+          GITEA_RELEASE_TOKEN: ${{ secrets.GOVOPLAN_RELEASE_TOKEN }}
+        run: |
+          python tools/release/publish-runtime-release.py \
+            --tag "v$VERSION" \
+            --title "GovOPlaN v$VERSION runtime distribution" \
+            --asset runtime-output/govoplan-deploy.pyz \
+            --asset runtime-output/govoplan-deploy.pyz.sig \
+            --asset runtime-output/govoplan-deploy.pyz.sha256 \
+            --asset runtime-output/distribution-manifest.json \
+            --asset runtime-output/distribution-manifest.json.sha256 \
+            --asset runtime-output/distribution-keyring.json \
+            --asset runtime-output/context-amd64/composition.json \
+            --asset runtime-output/evidence/api-sbom.cdx.json \
+            --asset runtime-output/evidence/web-sbom.cdx.json \
+            --asset runtime-output/evidence/api-provenance.json \
+            --asset runtime-output/evidence/web-provenance.json
diff --git a/.gitignore b/.gitignore
index eb7c51a..8c5260a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,11 @@
 .ruff_cache/
 .venv/
 runtime/
+!tools/release/runtime/
+tools/release/runtime/*
+!tools/release/runtime/Dockerfile.api
+!tools/release/runtime/Dockerfile.web
+!tools/release/runtime/nginx.conf
 __pycache__/
 audit-reports/
 coverage/
diff --git a/docs/INSTALLATION_AND_DEPLOYMENT_ARCHITECTURE.md b/docs/INSTALLATION_AND_DEPLOYMENT_ARCHITECTURE.md
index d694503..81e073c 100644
--- a/docs/INSTALLATION_AND_DEPLOYMENT_ARCHITECTURE.md
+++ b/docs/INSTALLATION_AND_DEPLOYMENT_ARCHITECTURE.md
@@ -93,6 +93,8 @@ The private installation directory contains:
 | `load-balancer.cfg` | Non-secret HAProxy WebUI/API discovery configuration |
 | `plan.json` | Latest desired-state diff and readiness findings |
 | `receipt.json` | Last successfully applied immutable identities |
+| `distribution-manifest.json` | Canonical signed runtime/image selection adopted by the installer |
+| `distribution-keyring.json` | Explicitly installed public trust anchor for runtime releases |
 | `applied-state/` | Checksum-verified snapshot of the last healthy deployment bundle |
 | `operations/<id>/` | Private hash-chained deployment progress and recovery evidence |
 | `kubernetes.json` | Optional stateless multi-host Kubernetes export |
@@ -128,20 +130,56 @@ Those images must already contain the selected module set. The override exists
 only to exercise local orchestration before release artifacts exist; it is
 rejected for `self-hosted`.
 
+## Runtime Distribution Boundary
+
+The protected `Runtime Distribution` workflow builds GovOPlaN wheels first,
+resolves architecture-specific third-party wheels into offline wheelhouses, and
+then assembles the API images with `pip --no-index`. The target host never
+clones Git repositories and neither runtime image performs network package
+installation. Separate amd64/arm64 API and WebUI images are joined into OCI
+indexes and run as non-root identities. The release assets include CycloneDX
+application SBOMs, SLSA-style provenance, exact composition evidence, the
+single-file deployer, its detached Ed25519 signature, and a signed, expiring
+distribution manifest.
+
+The manifest contract is
+[`runtime-distribution-manifest.schema.json`](runtime-distribution-manifest.schema.json),
+and its separately distributed trust-anchor contract is
+[`runtime-distribution-keyring.schema.json`](runtime-distribution-keyring.schema.json).
+Publication is immutable: an existing Gitea release asset must have the same
+size and SHA-256 digest or publication fails.
+
+Adopt a downloaded or prefetched release only after obtaining the manifest
+digest and trusted keyring through the documented independent channel:
+
+```sh
+python3 govoplan-deploy.pyz verify-release \
+  --directory /srv/govoplan/installation \
+  --manifest ./distribution-manifest.json \
+  --manifest-sha256 "$(cut -d' ' -f1 distribution-manifest.json.sha256)" \
+  --trusted-keyring ./distribution-keyring.json \
+  --adopt
+```
+
+`doctor` and `apply` rehash both stored files, re-run OpenSSL Ed25519
+verification, enforce channel/expiry/revocation, compare every selected image,
+and prove that all enabled module ids occur in the signed image composition.
+An offline image index can bind prefetched OCI archives to the same exact image
+references and archive hashes; mutable tags or incomplete bundles are rejected.
+
 ## Current Production Gates
 
 The tool deliberately reports blockers instead of pretending the source tree is
 a production distribution:
 
-1. **OCI release artifacts.** The release pipeline does not yet publish pinned
-   multi-architecture API and WebUI images.
-2. **Signed distribution manifest.** A channel manifest must bind exact image
-   digests, Compose compatibility, SBOM/provenance references, and revocation
-   state. Recording a URL and checksum is not signature verification.
+1. **First publication.** The protected workflow and fail-closed artifact
+   contracts are implemented, but a release operator must configure the Gitea
+   registry/release tokens and runtime Ed25519 key, publish the first pinned
+   release, and retain its amd64/arm64 readiness evidence.
 3. **First administrator.** Production needs a one-time, restricted enrollment
    identity. The development bootstrap must not be enabled in production.
-4. **Image/module composition.** The selected module set must be proven present
-   in the exact image or installed from verified offline artifacts before it is
+4. **Image/module composition.** The deployer now enforces the signed
+   composition. A selected module not shipped by that release cannot be
    enabled.
 5. **Deployment agent.** Web updates need a separate privileged reconciler with
    a typed command allowlist. The API and browser must never receive the Docker
@@ -353,22 +391,25 @@ of the reviewed update recipe instead of a non-functional update button.
 
 ## Distribution Workflow
 
-The downloadable entry point should eventually be:
+The downloadable entry point is a release asset. Obtain the zipapp, detached
+signature, checksum, and trusted public keyring through independently
+authenticated paths before execution:
 
 ```sh
 curl --proto '=https' --tlsv1.2 --fail --location \
-  https://govoplan.add-ideas.de/install/v1/bootstrap.pyz \
-  --output govoplan-bootstrap.pyz
-python3 govoplan-bootstrap.pyz init
+  https://git.add-ideas.de/GovOPlaN/govoplan/releases/download/vX.Y.Z/govoplan-deploy.pyz \
+  --output govoplan-deploy.pyz
+sha256sum --check govoplan-deploy.pyz.sha256
+openssl pkeyutl -verify -pubin -inkey runtime-release-public.pem -rawin \
+  -in govoplan-deploy.pyz -sigfile govoplan-deploy.pyz.sig
+python3 govoplan-deploy.pyz init
 ```
 
-The published documentation must include an independent checksum/signature
-verification command before execution. The zipapp then downloads only a signed
-distribution manifest, verifies it against an embedded or explicitly installed
-keyring, and renders the same installation contract implemented here.
-
-The source-tree script is the test harness for that future zipapp. It is not yet
-the internet bootstrap artifact.
+The zipapp has no GovOPlaN package dependency. It accepts a bounded HTTPS
+manifest or a prefetched file, requires an independently supplied SHA-256
+digest and explicit trusted keyring, and executes OpenSSL with a fixed argument
+vector for Ed25519 verification. It never evaluates downloaded shell text or
+accepts an arbitrary command string.
 
 ## Verification
 
@@ -378,7 +419,9 @@ Run the focused tests:
 ./.venv/bin/python -m unittest -v tests.test_deployment_installer
 ```
 
-The tests cover profile restrictions, secret persistence, external endpoint
+The tests cover signed release adoption, tamper/expiry/revocation/unknown-key
+rejection, architecture composition, offline image integrity, profile
+restrictions, secret persistence, external endpoint
 requirements, managed Garage bootstrap, S3 policy, replica validation, HAProxy
 discovery configuration, Compose service selection, secret non-disclosure,
 service-specific environment isolation, private file modes, external endpoint
diff --git a/docs/SYSTEM_ADMINISTRATOR_LIFECYCLE_USER_STORY.md b/docs/SYSTEM_ADMINISTRATOR_LIFECYCLE_USER_STORY.md
index 5da86ac..f763215 100644
--- a/docs/SYSTEM_ADMINISTRATOR_LIFECYCLE_USER_STORY.md
+++ b/docs/SYSTEM_ADMINISTRATOR_LIFECYCLE_USER_STORY.md
@@ -141,6 +141,12 @@ The canonical backlog item is
 
 Implementation status as of the current source tree:
 
+- Slice 1 now has the source-controlled production artifact boundary: offline
+  per-architecture wheel resolution, non-root API/Web image definitions,
+  multi-architecture OCI publication, signed composition/SBOM/provenance,
+  immutable Gitea assets, a signed one-file deployer, and fail-closed manifest
+  adoption. The first real published release and cross-architecture runtime
+  evidence remain release-operator work rather than source-code claims.
 - Slice 6 has a working application-tier foundation: state profiles, shared
   object storage, runtime node registration/heartbeats/drain, fenced scheduler,
   migration serialization, exact-head startup waiting, Ops visibility, and a
diff --git a/docs/installation-spec.schema.json b/docs/installation-spec.schema.json
index 0314ead..0cff46d 100644
--- a/docs/installation-spec.schema.json
+++ b/docs/installation-spec.schema.json
@@ -83,6 +83,18 @@
           "type": "string",
           "pattern": "^$|^[0-9a-f]{64}$"
         },
+        "manifest_keyring_sha256": {
+          "type": "string",
+          "pattern": "^$|^[0-9a-f]{64}$"
+        },
+        "manifest_signature_key_id": {
+          "type": "string",
+          "pattern": "^$|^[A-Za-z0-9][A-Za-z0-9._:-]{0,127}$"
+        },
+        "composition_sha256": {
+          "type": "string",
+          "pattern": "^$|^[0-9a-f]{64}$"
+        },
         "api_image": {
           "type": "string",
           "minLength": 1,
diff --git a/docs/runtime-distribution-keyring.schema.json b/docs/runtime-distribution-keyring.schema.json
new file mode 100644
index 0000000..88c50ec
--- /dev/null
+++ b/docs/runtime-distribution-keyring.schema.json
@@ -0,0 +1,36 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://govoplan.add-ideas.de/schemas/runtime-distribution-keyring-v1.json",
+  "title": "GovOPlaN runtime distribution trust keyring",
+  "type": "object",
+  "additionalProperties": false,
+  "required": ["schema_version", "purpose", "keys"],
+  "properties": {
+    "schema_version": { "const": "1" },
+    "purpose": { "const": "govoplan-runtime-distribution" },
+    "keys": {
+      "type": "array",
+      "minItems": 1,
+      "items": {
+        "type": "object",
+        "additionalProperties": false,
+        "required": [
+          "key_id",
+          "algorithm",
+          "status",
+          "public_key_pem",
+          "not_before",
+          "expires_at"
+        ],
+        "properties": {
+          "key_id": { "type": "string", "minLength": 1, "maxLength": 128 },
+          "algorithm": { "const": "ed25519" },
+          "status": { "enum": ["active", "retired", "revoked"] },
+          "public_key_pem": { "type": "string", "minLength": 1, "maxLength": 8192 },
+          "not_before": { "type": "string", "format": "date-time" },
+          "expires_at": { "type": "string", "format": "date-time" }
+        }
+      }
+    }
+  }
+}
diff --git a/docs/runtime-distribution-manifest.schema.json b/docs/runtime-distribution-manifest.schema.json
new file mode 100644
index 0000000..d6451c1
--- /dev/null
+++ b/docs/runtime-distribution-manifest.schema.json
@@ -0,0 +1,123 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://govoplan.add-ideas.de/schemas/runtime-distribution-manifest-v1.json",
+  "title": "GovOPlaN runtime distribution manifest",
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "schema_version",
+    "channel",
+    "sequence",
+    "version",
+    "issued_at",
+    "expires_at",
+    "revoked",
+    "deployer",
+    "images",
+    "dependencies",
+    "composition",
+    "signatures"
+  ],
+  "properties": {
+    "schema_version": { "const": "1" },
+    "channel": { "type": "string", "pattern": "^[a-z][a-z0-9_]{1,63}$" },
+    "sequence": { "type": "integer", "minimum": 1 },
+    "version": { "type": "string", "minLength": 1, "maxLength": 128 },
+    "issued_at": { "type": "string", "format": "date-time" },
+    "expires_at": { "type": "string", "format": "date-time" },
+    "revoked": { "const": false },
+    "deployer": { "$ref": "#/$defs/artifact" },
+    "images": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["api", "web"],
+      "properties": {
+        "api": { "$ref": "#/$defs/image" },
+        "web": { "$ref": "#/$defs/image" }
+      }
+    },
+    "dependencies": {
+      "type": "object",
+      "minProperties": 1,
+      "propertyNames": { "pattern": "^[a-z][a-z0-9_]{1,63}$" },
+      "additionalProperties": { "$ref": "#/$defs/imageReference" }
+    },
+    "composition": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["sha256", "module_ids", "packages"],
+      "properties": {
+        "sha256": { "$ref": "#/$defs/sha256" },
+        "module_ids": {
+          "type": "array",
+          "uniqueItems": true,
+          "items": { "type": "string", "pattern": "^[a-z][a-z0-9_]{1,63}$" }
+        },
+        "packages": {
+          "type": "array",
+          "minItems": 1,
+          "items": {
+            "type": "object",
+            "additionalProperties": false,
+            "required": ["name", "version", "wheel_sha256"],
+            "properties": {
+              "name": { "type": "string", "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$" },
+              "version": { "type": "string", "minLength": 1, "maxLength": 128 },
+              "wheel_sha256": { "$ref": "#/$defs/sha256" }
+            }
+          }
+        }
+      }
+    },
+    "signatures": {
+      "type": "array",
+      "minItems": 1,
+      "items": {
+        "type": "object",
+        "additionalProperties": false,
+        "required": ["key_id", "algorithm", "value"],
+        "properties": {
+          "key_id": { "type": "string", "minLength": 1, "maxLength": 128 },
+          "algorithm": { "const": "ed25519" },
+          "value": { "type": "string", "minLength": 1, "maxLength": 256 }
+        }
+      }
+    }
+  },
+  "$defs": {
+    "sha256": { "type": "string", "pattern": "^[0-9a-f]{64}$" },
+    "imageReference": {
+      "type": "string",
+      "pattern": "^[^@\\s]+@sha256:[0-9a-f]{64}$",
+      "maxLength": 300
+    },
+    "artifact": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["url", "sha256"],
+      "properties": {
+        "url": { "type": "string", "format": "uri", "pattern": "^https://" },
+        "sha256": { "$ref": "#/$defs/sha256" }
+      }
+    },
+    "image": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["index", "platforms", "sbom", "provenance"],
+      "properties": {
+        "index": { "$ref": "#/$defs/imageReference" },
+        "platforms": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["linux/amd64", "linux/arm64"],
+          "properties": {
+            "linux/amd64": { "$ref": "#/$defs/imageReference" },
+            "linux/arm64": { "$ref": "#/$defs/imageReference" }
+          }
+        },
+        "sbom": { "$ref": "#/$defs/artifact" },
+        "provenance": { "$ref": "#/$defs/artifact" }
+      }
+    }
+  }
+}
diff --git a/tests/test_deployment_release_adoption.py b/tests/test_deployment_release_adoption.py
new file mode 100644
index 0000000..8e485c0
--- /dev/null
+++ b/tests/test_deployment_release_adoption.py
@@ -0,0 +1,207 @@
+from __future__ import annotations
+
+import base64
+from datetime import UTC, datetime, timedelta
+import hashlib
+from pathlib import Path
+import sys
+import tempfile
+import unittest
+
+from cryptography.hazmat.primitives import serialization
+from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
+
+
+META_ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(META_ROOT / "tools" / "deployment"))
+
+from govoplan_deploy.bundle import bundle_paths  # noqa: E402
+from govoplan_deploy.cli import main  # noqa: E402
+from govoplan_deploy.distribution import (  # noqa: E402
+    canonical_json,
+    canonical_signed_payload,
+)
+from govoplan_deploy.model import load_spec  # noqa: E402
+from govoplan_deploy.planning import static_checks  # noqa: E402
+
+
+class DeploymentReleaseAdoptionTests(unittest.TestCase):
+    def test_adopts_verified_manifest_and_makes_release_checks_pass(self) -> None:
+        with tempfile.TemporaryDirectory(prefix="govoplan-release-adopt-") as value:
+            root = Path(value)
+            self.assertEqual(
+                0,
+                main(
+                    [
+                        "init",
+                        "--directory",
+                        str(root),
+                        "--non-interactive",
+                        "--module-set",
+                        "core",
+                    ]
+                ),
+            )
+            manifest, keyring = self._signed_distribution()
+            manifest_path = root / "source-manifest.json"
+            keyring_path = root / "source-keyring.json"
+            encoded_manifest = canonical_json(manifest)
+            manifest_path.write_bytes(encoded_manifest)
+            keyring_path.write_bytes(canonical_json(keyring))
+
+            result = main(
+                [
+                    "verify-release",
+                    "--directory",
+                    str(root),
+                    "--manifest",
+                    str(manifest_path),
+                    "--manifest-sha256",
+                    hashlib.sha256(encoded_manifest).hexdigest(),
+                    "--trusted-keyring",
+                    str(keyring_path),
+                    "--adopt",
+                ]
+            )
+
+            self.assertEqual(0, result)
+            paths = bundle_paths(root)
+            spec = load_spec(paths.spec)
+            self.assertEqual("1.2.3", spec.release.version)
+            self.assertEqual("release-1", spec.release.manifest_signature_key_id)
+            self.assertTrue(spec.release.api_image.endswith("a" * 64))
+            release_checks = {
+                item.id: item for item in static_checks(spec, paths)
+                if item.id.startswith("release.") or item.id == "modules.image_composition"
+            }
+            self.assertEqual("ok", release_checks["release.manifest"].level)
+            self.assertEqual(
+                "ok", release_checks["release.signature_verification"].level
+            )
+            self.assertEqual("ok", release_checks["modules.image_composition"].level)
+
+    def test_rejects_manifest_whose_independent_digest_does_not_match(self) -> None:
+        with tempfile.TemporaryDirectory(prefix="govoplan-release-adopt-") as value:
+            root = Path(value)
+            main(
+                [
+                    "init",
+                    "--directory",
+                    str(root),
+                    "--non-interactive",
+                    "--module-set",
+                    "core",
+                ]
+            )
+            manifest, keyring = self._signed_distribution()
+            manifest_path = root / "source-manifest.json"
+            keyring_path = root / "source-keyring.json"
+            manifest_path.write_bytes(canonical_json(manifest))
+            keyring_path.write_bytes(canonical_json(keyring))
+
+            self.assertEqual(
+                1,
+                main(
+                    [
+                        "verify-release",
+                        "--directory",
+                        str(root),
+                        "--manifest",
+                        str(manifest_path),
+                        "--manifest-sha256",
+                        "0" * 64,
+                        "--trusted-keyring",
+                        str(keyring_path),
+                    ]
+                ),
+            )
+
+    @staticmethod
+    def _signed_distribution() -> tuple[dict[str, object], dict[str, object]]:
+        now = datetime.now(UTC)
+        private = Ed25519PrivateKey.generate()
+        public = private.public_key().public_bytes(
+            serialization.Encoding.PEM,
+            serialization.PublicFormat.SubjectPublicKeyInfo,
+        ).decode("ascii")
+        artifact = {
+            "url": "https://downloads.example.test/artifact.json",
+            "sha256": "f" * 64,
+        }
+        payload: dict[str, object] = {
+            "schema_version": "1",
+            "channel": "stable",
+            "sequence": 1,
+            "version": "1.2.3",
+            "issued_at": (now - timedelta(minutes=1)).isoformat(),
+            "expires_at": (now + timedelta(days=30)).isoformat(),
+            "revoked": False,
+            "deployer": {
+                "url": "https://downloads.example.test/govoplan-deploy.pyz",
+                "sha256": "e" * 64,
+            },
+            "images": {
+                "api": {
+                    "index": "registry.example/govoplan/api@sha256:" + "a" * 64,
+                    "platforms": {
+                        "linux/amd64": "registry.example/govoplan/api@sha256:" + "1" * 64,
+                        "linux/arm64": "registry.example/govoplan/api@sha256:" + "2" * 64,
+                    },
+                    "sbom": dict(artifact),
+                    "provenance": dict(artifact),
+                },
+                "web": {
+                    "index": "registry.example/govoplan/web@sha256:" + "b" * 64,
+                    "platforms": {
+                        "linux/amd64": "registry.example/govoplan/web@sha256:" + "3" * 64,
+                        "linux/arm64": "registry.example/govoplan/web@sha256:" + "4" * 64,
+                    },
+                    "sbom": dict(artifact),
+                    "provenance": dict(artifact),
+                },
+            },
+            "dependencies": {
+                "postgres": "docker.io/library/postgres@sha256:" + "5" * 64,
+                "redis": "docker.io/library/redis@sha256:" + "6" * 64,
+                "load_balancer": "docker.io/library/haproxy@sha256:" + "7" * 64,
+            },
+            "composition": {
+                "sha256": "c" * 64,
+                "module_ids": [],
+                "packages": [
+                    {
+                        "name": "govoplan-core",
+                        "version": "1.2.3",
+                        "wheel_sha256": "8" * 64,
+                    }
+                ],
+            },
+        }
+        payload["signatures"] = [
+            {
+                "key_id": "release-1",
+                "algorithm": "ed25519",
+                "value": base64.b64encode(
+                    private.sign(canonical_signed_payload(payload))
+                ).decode("ascii"),
+            }
+        ]
+        keyring = {
+            "schema_version": "1",
+            "purpose": "govoplan-runtime-distribution",
+            "keys": [
+                {
+                    "key_id": "release-1",
+                    "algorithm": "ed25519",
+                    "status": "active",
+                    "public_key_pem": public,
+                    "not_before": (now - timedelta(days=1)).isoformat(),
+                    "expires_at": (now + timedelta(days=365)).isoformat(),
+                }
+            ],
+        }
+        return payload, keyring
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tests/test_runtime_distribution.py b/tests/test_runtime_distribution.py
new file mode 100644
index 0000000..def7d0a
--- /dev/null
+++ b/tests/test_runtime_distribution.py
@@ -0,0 +1,201 @@
+from __future__ import annotations
+
+import base64
+from datetime import UTC, datetime, timedelta
+import hashlib
+from pathlib import Path
+import sys
+import tempfile
+import unittest
+
+from cryptography.hazmat.primitives import serialization
+from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
+
+
+META_ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(META_ROOT / "tools" / "deployment"))
+sys.path.insert(0, str(META_ROOT / "tools" / "release"))
+
+from govoplan_deploy.distribution import (  # noqa: E402
+    DistributionError,
+    canonical_signed_payload,
+    verify_manifest,
+    verify_manifest_binding,
+    verify_offline_image_index,
+)
+
+
+class RuntimeDistributionTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.now = datetime(2026, 8, 3, tzinfo=UTC)
+        self.private = Ed25519PrivateKey.generate()
+        public = self.private.public_key().public_bytes(
+            serialization.Encoding.PEM,
+            serialization.PublicFormat.SubjectPublicKeyInfo,
+        ).decode("ascii")
+        self.keyring = {
+            "schema_version": "1",
+            "purpose": "govoplan-runtime-distribution",
+            "keys": [
+                {
+                    "key_id": "release-1",
+                    "algorithm": "ed25519",
+                    "status": "active",
+                    "public_key_pem": public,
+                    "not_before": (self.now - timedelta(days=1)).isoformat(),
+                    "expires_at": (self.now + timedelta(days=365)).isoformat(),
+                }
+            ],
+        }
+
+    def test_verifies_signature_and_exact_runtime_binding(self) -> None:
+        payload = self._manifest()
+
+        key_id = verify_manifest(
+            payload,
+            self.keyring,
+            expected_channel="stable",
+            now=self.now,
+        )
+        verify_manifest_binding(
+            payload,
+            channel="stable",
+            version="1.2.3",
+            api_image=payload["images"]["api"]["index"],
+            web_image=payload["images"]["web"]["index"],
+            enabled_modules=("access", "files"),
+            composition_sha256="c" * 64,
+            dependencies=payload["dependencies"],
+        )
+
+        self.assertEqual("release-1", key_id)
+
+    def test_tamper_expiry_revocation_and_unknown_key_fail_closed(self) -> None:
+        payload = self._manifest()
+        payload["composition"]["module_ids"].append("mail")
+        with self.assertRaisesRegex(DistributionError, "signature verification"):
+            verify_manifest(payload, self.keyring, now=self.now)
+
+        expired = self._manifest()
+        expired["expires_at"] = (self.now - timedelta(seconds=1)).isoformat()
+        expired["signatures"] = [self._signature(expired)]
+        with self.assertRaisesRegex(DistributionError, "expired"):
+            verify_manifest(expired, self.keyring, now=self.now)
+
+        revoked = self._manifest()
+        revoked["revoked"] = True
+        revoked["signatures"] = [self._signature(revoked)]
+        with self.assertRaisesRegex(DistributionError, "revoked"):
+            verify_manifest(revoked, self.keyring, now=self.now)
+
+        unknown = self._manifest()
+        unknown["signatures"][0]["key_id"] = "other-key"
+        with self.assertRaisesRegex(DistributionError, "active trusted key"):
+            verify_manifest(unknown, self.keyring, now=self.now)
+
+    def test_offline_image_index_is_complete_and_digest_bound(self) -> None:
+        with tempfile.TemporaryDirectory(prefix="govoplan-offline-images-") as value:
+            root = Path(value)
+            api = root / "api.oci.tar"
+            web = root / "web.oci.tar"
+            api.write_bytes(b"api archive")
+            web.write_bytes(b"web archive")
+            api_ref = "registry.example/govoplan/api@sha256:" + "a" * 64
+            web_ref = "registry.example/govoplan/web@sha256:" + "b" * 64
+            index = {
+                "schema_version": "1",
+                "images": [
+                    {
+                        "reference": api_ref,
+                        "archive": api.name,
+                        "sha256": hashlib.sha256(api.read_bytes()).hexdigest(),
+                    },
+                    {
+                        "reference": web_ref,
+                        "archive": web.name,
+                        "sha256": hashlib.sha256(web.read_bytes()).hexdigest(),
+                    },
+                ],
+            }
+
+            paths = verify_offline_image_index(
+                index,
+                root=root,
+                expected_references=(api_ref, web_ref),
+            )
+            self.assertEqual((api, web), paths)
+
+            index["images"][1]["sha256"] = "0" * 64
+            with self.assertRaisesRegex(DistributionError, "digest mismatch"):
+                verify_offline_image_index(
+                    index,
+                    root=root,
+                    expected_references=(api_ref, web_ref),
+                )
+
+    def _manifest(self) -> dict[str, object]:
+        artifact = {"url": "https://downloads.example.test/artifact.json", "sha256": "d" * 64}
+        manifest: dict[str, object] = {
+            "schema_version": "1",
+            "channel": "stable",
+            "sequence": 1,
+            "version": "1.2.3",
+            "issued_at": (self.now - timedelta(minutes=1)).isoformat(),
+            "expires_at": (self.now + timedelta(days=30)).isoformat(),
+            "revoked": False,
+            "deployer": {
+                "url": "https://downloads.example.test/govoplan-deploy.pyz",
+                "sha256": "e" * 64,
+            },
+            "images": {
+                "api": {
+                    "index": "registry.example/govoplan/api@sha256:" + "a" * 64,
+                    "platforms": {
+                        "linux/amd64": "registry.example/govoplan/api@sha256:" + "1" * 64,
+                        "linux/arm64": "registry.example/govoplan/api@sha256:" + "2" * 64,
+                    },
+                    "sbom": dict(artifact),
+                    "provenance": dict(artifact),
+                },
+                "web": {
+                    "index": "registry.example/govoplan/web@sha256:" + "b" * 64,
+                    "platforms": {
+                        "linux/amd64": "registry.example/govoplan/web@sha256:" + "3" * 64,
+                        "linux/arm64": "registry.example/govoplan/web@sha256:" + "4" * 64,
+                    },
+                    "sbom": dict(artifact),
+                    "provenance": dict(artifact),
+                },
+            },
+            "dependencies": {
+                "postgres": "docker.io/library/postgres@sha256:" + "5" * 64,
+                "redis": "docker.io/library/redis@sha256:" + "6" * 64,
+                "load_balancer": "docker.io/library/haproxy@sha256:" + "7" * 64,
+            },
+            "composition": {
+                "sha256": "c" * 64,
+                "module_ids": ["access", "files"],
+                "packages": [
+                    {
+                        "name": "govoplan-core",
+                        "version": "1.2.3",
+                        "wheel_sha256": "8" * 64,
+                    }
+                ],
+            },
+        }
+        manifest["signatures"] = [self._signature(manifest)]
+        return manifest
+
+    def _signature(self, payload: dict[str, object]) -> dict[str, str]:
+        return {
+            "key_id": "release-1",
+            "algorithm": "ed25519",
+            "value": base64.b64encode(
+                self.private.sign(canonical_signed_payload(payload))
+            ).decode("ascii"),
+        }
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tests/test_runtime_distribution_build.py b/tests/test_runtime_distribution_build.py
new file mode 100644
index 0000000..e7b4397
--- /dev/null
+++ b/tests/test_runtime_distribution_build.py
@@ -0,0 +1,133 @@
+from __future__ import annotations
+
+import argparse
+import importlib.util
+import json
+from pathlib import Path
+import sys
+import tempfile
+import unittest
+
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+def _load(name: str, path: Path):
+    spec = importlib.util.spec_from_file_location(name, path)
+    assert spec is not None and spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+OCI = _load("resolve_oci_platforms", ROOT / "tools/release/resolve-oci-platforms.py")
+FINALIZE = _load(
+    "finalize_runtime_distribution",
+    ROOT / "tools/release/finalize-runtime-distribution.py",
+)
+
+
+class RuntimeDistributionBuildTests(unittest.TestCase):
+    def test_resolves_platforms_and_builds_evidence_descriptor(self) -> None:
+        index = {
+            "schemaVersion": 2,
+            "manifests": [
+                {
+                    "digest": "sha256:" + "1" * 64,
+                    "platform": {"os": "linux", "architecture": "amd64"},
+                },
+                {
+                    "digest": "sha256:" + "2" * 64,
+                    "platform": {"os": "linux", "architecture": "arm64"},
+                },
+            ],
+        }
+        metadata = OCI.resolve_platforms(
+            index,
+            repository="registry.example/govoplan/api",
+            index_digest="sha256:" + "a" * 64,
+        )
+        self.assertEqual(
+            "registry.example/govoplan/api@sha256:" + "1" * 64,
+            metadata["platforms"]["linux/amd64"],
+        )
+
+        with tempfile.TemporaryDirectory(prefix="govoplan-runtime-finalize-") as value:
+            root = Path(value)
+            composition = {
+                "schema_version": "1",
+                "python": {
+                    "packages": [
+                        {
+                            "package": "govoplan-core",
+                            "version": "1.2.3",
+                            "sha256": "8" * 64,
+                        }
+                    ],
+                    "module_ids": ["access"],
+                    "wheelhouse_sha256": "9" * 64,
+                    "wheel_count": 1,
+                },
+                "web": {"sha256": "7" * 64, "file_count": 4},
+            }
+            (root / "composition.json").write_text(json.dumps(composition))
+            (root / "api.json").write_text(json.dumps(metadata))
+            web_metadata = {
+                "index": "registry.example/govoplan/web@sha256:" + "b" * 64,
+                "platforms": {
+                    "linux/amd64": "registry.example/govoplan/web@sha256:" + "3" * 64,
+                    "linux/arm64": "registry.example/govoplan/web@sha256:" + "4" * 64,
+                },
+            }
+            (root / "web.json").write_text(json.dumps(web_metadata))
+            deployer = root / "govoplan-deploy.pyz"
+            deployer.write_bytes(b"zipapp")
+            args = argparse.Namespace(
+                composition=root / "composition.json",
+                api_metadata=root / "api.json",
+                web_metadata=root / "web.json",
+                deployer=deployer,
+                deployer_url="https://downloads.example/govoplan-deploy.pyz",
+                artifact_base_url="https://downloads.example/runtime/v1.2.3",
+                source_commit="f" * 40,
+                version="1.2.3",
+                channel="stable",
+                sequence=1,
+                expires_days=30,
+                dependency=[
+                    "postgres=docker.io/library/postgres@sha256:" + "5" * 64,
+                    "redis=docker.io/library/redis@sha256:" + "6" * 64,
+                ],
+                output_directory=root / "evidence",
+                descriptor=root / "descriptor.json",
+            )
+
+            descriptor = FINALIZE.finalize(args)
+
+            self.assertEqual(["access"], descriptor["composition"]["module_ids"])
+            self.assertEqual(
+                "registry.example/govoplan/api@sha256:" + "a" * 64,
+                descriptor["images"]["api"]["index"],
+            )
+            self.assertTrue((root / "evidence/api-sbom.cdx.json").is_file())
+            self.assertTrue((root / "evidence/web-provenance.json").is_file())
+
+    def test_rejects_incomplete_oci_index(self) -> None:
+        with self.assertRaisesRegex(ValueError, "linux/amd64 and linux/arm64"):
+            OCI.resolve_platforms(
+                {
+                    "manifests": [
+                        {
+                            "digest": "sha256:" + "1" * 64,
+                            "platform": {"os": "linux", "architecture": "amd64"},
+                        }
+                    ]
+                },
+                repository="registry.example/govoplan/api",
+                index_digest="sha256:" + "a" * 64,
+            )
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tests/test_runtime_image_context.py b/tests/test_runtime_image_context.py
new file mode 100644
index 0000000..ab04568
--- /dev/null
+++ b/tests/test_runtime_image_context.py
@@ -0,0 +1,153 @@
+from __future__ import annotations
+
+import importlib.util
+import json
+from pathlib import Path
+import sys
+import tempfile
+import unittest
+import zipfile
+
+
+SCRIPT = (
+    Path(__file__).resolve().parents[1]
+    / "tools"
+    / "release"
+    / "prepare-runtime-context.py"
+)
+SPEC = importlib.util.spec_from_file_location("prepare_runtime_context", SCRIPT)
+assert SPEC is not None and SPEC.loader is not None
+MODULE = importlib.util.module_from_spec(SPEC)
+sys.modules[SPEC.name] = MODULE
+SPEC.loader.exec_module(MODULE)
+
+
+class RuntimeImageContextTests(unittest.TestCase):
+    def test_builds_deterministic_network_free_context(self) -> None:
+        with tempfile.TemporaryDirectory(prefix="govoplan-runtime-context-") as value:
+            root = Path(value)
+            wheelhouse = root / "input-wheels"
+            web = root / "web"
+            wheelhouse.mkdir()
+            web.mkdir()
+            self._wheel(
+                wheelhouse / "govoplan_core-1.2.3-py3-none-any.whl",
+                package="govoplan-core",
+                version="1.2.3",
+                module_ids=(),
+            )
+            self._wheel(
+                wheelhouse / "govoplan_files-1.2.3-py3-none-any.whl",
+                package="govoplan-files",
+                version="1.2.3",
+                module_ids=("files",),
+            )
+            self._wheel(
+                wheelhouse / "sqlalchemy-2.0.0-py3-none-any.whl",
+                package="SQLAlchemy",
+                version="2.0.0",
+                module_ids=(),
+            )
+            (web / "index.html").write_text("<main>GovOPlaN</main>\n", encoding="utf-8")
+
+            composition = MODULE.prepare_context(
+                wheelhouse=wheelhouse,
+                web_dist=web,
+                output=root / "context",
+                required_modules=("files",),
+                source_date_epoch=1_700_000_000,
+            )
+
+            self.assertEqual(["files"], composition["python"]["module_ids"])
+            self.assertEqual(2, composition["python"]["wheel_count"])
+            requirements = (root / "context" / "requirements-runtime.txt").read_text()
+            self.assertEqual(
+                "govoplan-core[server]==1.2.3\ngovoplan-files==1.2.3\n",
+                requirements,
+            )
+            published = json.loads(
+                (
+                    root
+                    / "context"
+                    / "web-dist"
+                    / ".well-known"
+                    / "govoplan-composition.json"
+                ).read_text()
+            )
+            self.assertEqual(composition, published)
+
+    def test_rejects_missing_required_module(self) -> None:
+        with tempfile.TemporaryDirectory(prefix="govoplan-runtime-context-") as value:
+            root = Path(value)
+            wheelhouse = root / "wheels"
+            web = root / "web"
+            wheelhouse.mkdir()
+            web.mkdir()
+            self._wheel(
+                wheelhouse / "govoplan_core-1.0.0-py3-none-any.whl",
+                package="govoplan-core",
+                version="1.0.0",
+                module_ids=(),
+            )
+            (web / "index.html").write_text("ok", encoding="utf-8")
+
+            with self.assertRaisesRegex(MODULE.ContextError, "missing required"):
+                MODULE.prepare_context(
+                    wheelhouse=wheelhouse,
+                    web_dist=web,
+                    output=root / "context",
+                    required_modules=("mail",),
+                )
+
+    def test_rejects_symlinked_web_payload(self) -> None:
+        with tempfile.TemporaryDirectory(prefix="govoplan-runtime-context-") as value:
+            root = Path(value)
+            wheelhouse = root / "wheels"
+            web = root / "web"
+            wheelhouse.mkdir()
+            web.mkdir()
+            self._wheel(
+                wheelhouse / "govoplan_core-1.0.0-py3-none-any.whl",
+                package="govoplan-core",
+                version="1.0.0",
+                module_ids=(),
+            )
+            outside = root / "outside"
+            outside.write_text("not part of dist", encoding="utf-8")
+            (web / "index.html").symlink_to(outside)
+
+            with self.assertRaisesRegex(MODULE.ContextError, "symlink"):
+                MODULE.prepare_context(
+                    wheelhouse=wheelhouse,
+                    web_dist=web,
+                    output=root / "context",
+                )
+
+    @staticmethod
+    def _wheel(
+        path: Path,
+        *,
+        package: str,
+        version: str,
+        module_ids: tuple[str, ...],
+    ) -> None:
+        dist_info = package.replace("-", "_") + f"-{version}.dist-info"
+        with zipfile.ZipFile(path, "w") as archive:
+            archive.writestr(
+                f"{dist_info}/METADATA",
+                f"Metadata-Version: 2.1\nName: {package}\nVersion: {version}\n",
+            )
+            if module_ids:
+                rows = "\n".join(
+                    f"{module_id} = example.module:manifest"
+                    for module_id in module_ids
+                )
+                archive.writestr(
+                    f"{dist_info}/entry_points.txt",
+                    f"[govoplan.modules]\n{rows}\n",
+                )
+            archive.writestr(f"{package.replace('-', '_')}/__init__.py", "")
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tools/deployment/govoplan_deploy/bundle.py b/tools/deployment/govoplan_deploy/bundle.py
index 3032cd4..afbbad3 100644
--- a/tools/deployment/govoplan_deploy/bundle.py
+++ b/tools/deployment/govoplan_deploy/bundle.py
@@ -24,6 +24,8 @@ GARAGE_CONFIG_FILENAME = "garage.toml"
 LOAD_BALANCER_CONFIG_FILENAME = "load-balancer.cfg"
 PLAN_FILENAME = "plan.json"
 RECEIPT_FILENAME = "receipt.json"
+MANIFEST_FILENAME = "distribution-manifest.json"
+KEYRING_FILENAME = "distribution-keyring.json"
 LOCK_FILENAME = ".deployment.lock"
 RUNTIME_ENV_KEYS = (
     "APP_ENV",
@@ -87,6 +89,8 @@ class BundlePaths:
     load_balancer_config: Path
     plan: Path
     receipt: Path
+    manifest: Path
+    keyring: Path
     lock: Path
 
 
@@ -104,6 +108,8 @@ def bundle_paths(root: Path) -> BundlePaths:
         load_balancer_config=resolved / LOAD_BALANCER_CONFIG_FILENAME,
         plan=resolved / PLAN_FILENAME,
         receipt=resolved / RECEIPT_FILENAME,
+        manifest=resolved / MANIFEST_FILENAME,
+        keyring=resolved / KEYRING_FILENAME,
         lock=resolved / LOCK_FILENAME,
     )
 
diff --git a/tools/deployment/govoplan_deploy/cli.py b/tools/deployment/govoplan_deploy/cli.py
index 0df22b5..2727504 100644
--- a/tools/deployment/govoplan_deploy/cli.py
+++ b/tools/deployment/govoplan_deploy/cli.py
@@ -8,6 +8,7 @@ from dataclasses import replace
 from datetime import UTC, datetime
 import fcntl
 import getpass
+import hashlib
 import json
 import os
 from pathlib import Path
@@ -36,6 +37,20 @@ from .bundle import (
     write_env,
 )
 from .cluster_evidence import collect_kubernetes_evidence
+from .distribution import (
+    MAX_KEYRING_BYTES,
+    MAX_MANIFEST_BYTES,
+    MAX_OFFLINE_INDEX_BYTES,
+    DistributionError,
+    canonical_json as canonical_distribution_json,
+    decode_json_bytes,
+    fetch_bounded_https,
+    load_bounded_json,
+    read_bounded_bytes,
+    verify_offline_image_index,
+    verify_manifest,
+    verify_manifest_binding,
+)
 from .model import (
     ComponentConfig,
     DEFAULT_GARAGE_IMAGE,
@@ -127,6 +142,43 @@ def build_parser() -> argparse.ArgumentParser:
     _directory_argument(status)
     status.add_argument("--json", action="store_true", help="Print JSON.")
 
+    verify_release = subparsers.add_parser(
+        "verify-release",
+        help="Verify and optionally adopt a signed runtime distribution.",
+    )
+    _directory_argument(verify_release)
+    manifest_source = verify_release.add_mutually_exclusive_group(required=True)
+    manifest_source.add_argument("--manifest", type=Path)
+    manifest_source.add_argument("--manifest-url")
+    verify_release.add_argument(
+        "--manifest-sha256",
+        required=True,
+        help="Independently obtained SHA-256 digest of the signed manifest.",
+    )
+    verify_release.add_argument("--trusted-keyring", type=Path, required=True)
+    verify_release.add_argument(
+        "--allow-private-release-host",
+        action="store_true",
+        help="Allow an explicitly selected private HTTPS release mirror.",
+    )
+    verify_release.add_argument(
+        "--adopt",
+        action="store_true",
+        help="Store the verified trust material and select its pinned images.",
+    )
+
+    offline_images = subparsers.add_parser(
+        "verify-offline-images",
+        help="Verify prefetched OCI archives against the adopted distribution.",
+    )
+    _directory_argument(offline_images)
+    offline_images.add_argument("--index", type=Path, required=True)
+    offline_images.add_argument(
+        "--load",
+        action="store_true",
+        help="Load verified archives into Docker using fixed image-load commands.",
+    )
+
     kubernetes = subparsers.add_parser(
         "render-kubernetes",
         help="Export the stateless multi-host runtime for Kubernetes.",
@@ -312,6 +364,10 @@ def main(argv: Sequence[str] | None = None) -> int:
             return _apply(args)
         if args.command == "status":
             return _status(args)
+        if args.command == "verify-release":
+            return _verify_release(args)
+        if args.command == "verify-offline-images":
+            return _verify_offline_images(args)
         if args.command == "render-kubernetes":
             return _render_kubernetes(args)
         if args.command == "verify-kubernetes":
@@ -320,7 +376,13 @@ def main(argv: Sequence[str] | None = None) -> int:
             return _operations(args)
         if args.command == "recover":
             return _recover(args)
-    except (SpecError, ValueError, OSError, subprocess.SubprocessError) as exc:
+    except (
+        DistributionError,
+        SpecError,
+        ValueError,
+        OSError,
+        subprocess.SubprocessError,
+    ) as exc:
         print(f"error: {exc}", file=sys.stderr)
         return 1
     raise RuntimeError(f"unsupported command: {args.command}")
@@ -617,6 +679,198 @@ def _status(args: argparse.Namespace) -> int:
     return 0
 
 
+def _verify_release(args: argparse.Namespace) -> int:
+    paths = bundle_paths(args.directory)
+    spec = load_spec(paths.spec)
+    expected_digest = str(args.manifest_sha256 or "").strip().lower()
+    if len(expected_digest) != 64 or any(
+        character not in "0123456789abcdef" for character in expected_digest
+    ):
+        raise ValueError("--manifest-sha256 must be a lowercase SHA-256 digest")
+    manifest_url = str(args.manifest_url or "").strip()
+    if manifest_url:
+        encoded_manifest = fetch_bounded_https(
+            manifest_url,
+            maximum_bytes=MAX_MANIFEST_BYTES,
+            allow_private_host=args.allow_private_release_host,
+        )
+        manifest = decode_json_bytes(
+            encoded_manifest,
+            label="distribution manifest",
+        )
+        actual_digest = hashlib.sha256(encoded_manifest).hexdigest()
+    else:
+        manifest_path = args.manifest.expanduser().resolve()
+        encoded_manifest = read_bounded_bytes(
+            manifest_path,
+            maximum_bytes=MAX_MANIFEST_BYTES,
+        )
+        manifest = load_bounded_json(
+            manifest_path,
+            maximum_bytes=MAX_MANIFEST_BYTES,
+        )
+        actual_digest = hashlib.sha256(encoded_manifest).hexdigest()
+    if encoded_manifest != canonical_distribution_json(manifest):
+        raise DistributionError("distribution manifest is not canonical JSON")
+    if actual_digest != expected_digest:
+        raise DistributionError("distribution manifest SHA-256 does not match")
+    keyring_path = args.trusted_keyring.expanduser().resolve()
+    keyring = load_bounded_json(keyring_path, maximum_bytes=MAX_KEYRING_BYTES)
+    encoded_keyring = canonical_distribution_json(keyring)
+    keyring_digest = hashlib.sha256(encoded_keyring).hexdigest()
+    key_id = verify_manifest(
+        manifest,
+        keyring,
+        expected_channel=spec.release.channel,
+    )
+    dependencies = _selected_dependency_images(spec, manifest=manifest)
+    verify_manifest_binding(
+        manifest,
+        channel=str(manifest["channel"]),
+        version=str(manifest["version"]),
+        api_image=str(manifest["images"]["api"]["index"]),
+        web_image=str(manifest["images"]["web"]["index"]),
+        enabled_modules=spec.enabled_modules,
+        composition_sha256=str(manifest["composition"]["sha256"]),
+        dependencies=dependencies,
+    )
+    print(
+        f"Verified GovOPlaN {manifest['version']} ({manifest['channel']}) "
+        f"with trusted key {key_id}."
+    )
+    if not args.adopt:
+        return 0
+
+    images = manifest["images"]
+    dependency_images = manifest["dependencies"]
+    release = replace(
+        spec.release,
+        channel=str(manifest["channel"]),
+        version=str(manifest["version"]),
+        manifest_url=manifest_url,
+        manifest_sha256=expected_digest,
+        manifest_keyring_sha256=keyring_digest,
+        manifest_signature_key_id=key_id,
+        composition_sha256=str(manifest["composition"]["sha256"]),
+        api_image=str(images["api"]["index"]),
+        web_image=str(images["web"]["index"]),
+    )
+    components = replace(
+        spec.components,
+        postgres=replace(
+            spec.components.postgres,
+            image=(
+                str(dependency_images["postgres"])
+                if spec.components.postgres.mode == "managed"
+                else spec.components.postgres.image
+            ),
+        ),
+        redis=replace(
+            spec.components.redis,
+            image=(
+                str(dependency_images["redis"])
+                if spec.components.redis.mode == "managed"
+                else spec.components.redis.image
+            ),
+        ),
+        mail=replace(
+            spec.components.mail,
+            image=(
+                str(dependency_images["test_mail"])
+                if spec.components.mail.mode == "test-mail"
+                else spec.components.mail.image
+            ),
+        ),
+        storage=replace(
+            spec.components.storage,
+            image=(
+                str(dependency_images["garage"])
+                if spec.components.storage.mode == "garage"
+                else spec.components.storage.image
+            ),
+        ),
+        load_balancer=replace(
+            spec.components.load_balancer,
+            image=str(dependency_images["load_balancer"]),
+        ),
+    )
+    adopted = parse_spec(replace(spec, release=release, components=components).to_dict())
+    ensure_private_directory(paths.root)
+    atomic_write(paths.manifest, encoded_manifest, mode=0o644)
+    atomic_write(
+        paths.keyring,
+        encoded_keyring,
+        mode=0o644,
+    )
+    secrets = reconcile_runtime_environment(adopted, read_env(paths.env))
+    _write_bundle(adopted, paths, secrets)
+    print(f"Adopted immutable runtime distribution in {paths.root}.")
+    return 0
+
+
+def _verify_offline_images(args: argparse.Namespace) -> int:
+    paths = bundle_paths(args.directory)
+    spec = load_spec(paths.spec)
+    manifest = load_bounded_json(
+        paths.manifest,
+        maximum_bytes=MAX_MANIFEST_BYTES,
+    )
+    index_path = args.index.expanduser().resolve()
+    index = load_bounded_json(
+        index_path,
+        maximum_bytes=MAX_OFFLINE_INDEX_BYTES,
+    )
+    selected_dependencies = _selected_dependency_images(spec, manifest=manifest)
+    expected = (
+        str(manifest["images"]["api"]["index"]),
+        str(manifest["images"]["web"]["index"]),
+        *tuple(selected_dependencies.values()),
+    )
+    archives = verify_offline_image_index(
+        index,
+        root=index_path.parent,
+        expected_references=expected,
+    )
+    print(f"Verified {len(archives)} prefetched OCI image archive(s).")
+    if not args.load:
+        return 0
+    docker = shutil.which("docker")
+    if docker is None:
+        raise ValueError("Docker CLI is required to load offline images")
+    for archive in archives:
+        _run([docker, "image", "load", "--input", str(archive)], cwd=paths.root)
+    for reference in expected:
+        _run([docker, "image", "inspect", reference], cwd=paths.root)
+    print("Loaded and inspected every adopted offline image identity.")
+    return 0
+
+
+def _selected_dependency_images(
+    spec: InstallationSpec,
+    *,
+    manifest: Mapping[str, object],
+) -> dict[str, str]:
+    available = manifest.get("dependencies")
+    if not isinstance(available, dict):
+        raise DistributionError("distribution dependencies are invalid")
+    names = ["load_balancer"]
+    if spec.components.postgres.mode == "managed":
+        names.append("postgres")
+    if spec.components.redis.mode == "managed":
+        names.append("redis")
+    if spec.components.mail.mode == "test-mail":
+        names.append("test_mail")
+    if spec.components.storage.mode == "garage":
+        names.append("garage")
+    missing = [name for name in names if not isinstance(available.get(name), str)]
+    if missing:
+        raise DistributionError(
+            "distribution is missing selected dependency images: "
+            + ", ".join(missing)
+        )
+    return {name: str(available[name]) for name in names}
+
+
 def _render_kubernetes(args: argparse.Namespace) -> int:
     paths = bundle_paths(args.directory)
     spec = load_spec(paths.spec)
@@ -727,6 +981,9 @@ def _deployment_receipt(
             "channel": spec.release.channel,
             "version": spec.release.version,
             "manifest_sha256": spec.release.manifest_sha256,
+            "manifest_keyring_sha256": spec.release.manifest_keyring_sha256,
+            "manifest_signature_key_id": spec.release.manifest_signature_key_id,
+            "composition_sha256": spec.release.composition_sha256,
             "api_image": spec.release.api_image,
             "web_image": spec.release.web_image,
         },
@@ -770,6 +1027,9 @@ def _updated_spec(
             if args.manifest_sha256 is not None
             else current.release.manifest_sha256
         ),
+        manifest_keyring_sha256=current.release.manifest_keyring_sha256,
+        manifest_signature_key_id=current.release.manifest_signature_key_id,
+        composition_sha256=current.release.composition_sha256,
         api_image=args.api_image or current.release.api_image,
         web_image=args.web_image or current.release.web_image,
     )
diff --git a/tools/deployment/govoplan_deploy/distribution.py b/tools/deployment/govoplan_deploy/distribution.py
new file mode 100644
index 0000000..98d79ce
--- /dev/null
+++ b/tools/deployment/govoplan_deploy/distribution.py
@@ -0,0 +1,651 @@
+"""Bounded verification for signed GovOPlaN runtime distributions."""
+
+from __future__ import annotations
+
+import base64
+from datetime import UTC, datetime
+import hashlib
+import ipaddress
+import json
+import os
+from pathlib import Path
+import re
+import socket
+import stat
+import subprocess
+import tempfile
+from typing import Any, Mapping
+from urllib.parse import urlsplit
+from urllib.request import Request, urlopen
+
+
+MAX_MANIFEST_BYTES = 4 * 1024 * 1024
+MAX_KEYRING_BYTES = 1024 * 1024
+MAX_OFFLINE_INDEX_BYTES = 4 * 1024 * 1024
+MAX_OFFLINE_IMAGE_BYTES = 16 * 1024 * 1024 * 1024
+SHA256 = re.compile(r"^[0-9a-f]{64}$")
+DIGEST_IMAGE = re.compile(r"^[^@\s]+@sha256:[0-9a-f]{64}$")
+TOKEN = re.compile(r"^[A-Za-z0-9][A-Za-z0-9._+!-]{0,127}$")
+MODULE_ID = re.compile(r"^[a-z][a-z0-9_]{1,63}$")
+KEY_ID = re.compile(r"^[A-Za-z0-9][A-Za-z0-9._:-]{0,127}$")
+PLATFORMS = ("linux/amd64", "linux/arm64")
+MANIFEST_FILENAME = "distribution-manifest.json"
+KEYRING_FILENAME = "distribution-keyring.json"
+
+
+class DistributionError(ValueError):
+    """Distribution evidence is absent, malformed, or untrusted."""
+
+
+def canonical_signed_payload(payload: Mapping[str, Any]) -> bytes:
+    unsigned = dict(payload)
+    unsigned.pop("signatures", None)
+    return json.dumps(
+        unsigned,
+        ensure_ascii=False,
+        separators=(",", ":"),
+        sort_keys=True,
+    ).encode("utf-8")
+
+
+def canonical_json(payload: Mapping[str, Any]) -> bytes:
+    return (
+        json.dumps(payload, ensure_ascii=False, indent=2, sort_keys=True) + "\n"
+    ).encode("utf-8")
+
+
+def load_bounded_json(path: Path, *, maximum_bytes: int) -> dict[str, Any]:
+    encoded = read_bounded_bytes(path, maximum_bytes=maximum_bytes)
+    try:
+        value = json.loads(encoded)
+    except (UnicodeDecodeError, json.JSONDecodeError) as exc:
+        raise DistributionError(f"trusted JSON file is malformed: {path}") from exc
+    if not isinstance(value, dict):
+        raise DistributionError(f"trusted JSON root must be an object: {path}")
+    return value
+
+
+def read_bounded_bytes(path: Path, *, maximum_bytes: int) -> bytes:
+    flags = os.O_RDONLY | getattr(os, "O_NOFOLLOW", 0)
+    try:
+        descriptor = os.open(path, flags)
+    except OSError as exc:
+        raise DistributionError(f"cannot open trusted JSON file: {path}") from exc
+    try:
+        opened = os.fstat(descriptor)
+        if not stat.S_ISREG(opened.st_mode) or opened.st_size > maximum_bytes:
+            raise DistributionError(f"trusted JSON file is invalid or too large: {path}")
+        chunks: list[bytes] = []
+        total = 0
+        while True:
+            chunk = os.read(descriptor, min(64 * 1024, maximum_bytes + 1 - total))
+            if not chunk:
+                break
+            chunks.append(chunk)
+            total += len(chunk)
+            if total > maximum_bytes:
+                raise DistributionError(f"trusted JSON file is too large: {path}")
+        final = os.fstat(descriptor)
+        if (opened.st_dev, opened.st_ino, opened.st_size, opened.st_mtime_ns) != (
+            final.st_dev,
+            final.st_ino,
+            final.st_size,
+            final.st_mtime_ns,
+        ):
+            raise DistributionError(f"trusted JSON file changed while read: {path}")
+    finally:
+        os.close(descriptor)
+    return b"".join(chunks)
+
+
+def fetch_bounded_https(
+    url: str,
+    *,
+    maximum_bytes: int,
+    timeout_seconds: float = 15.0,
+    allow_private_host: bool = False,
+) -> bytes:
+    parsed = urlsplit(url)
+    if parsed.scheme != "https" or not parsed.hostname:
+        raise DistributionError("distribution downloads require an absolute HTTPS URL")
+    if parsed.username or parsed.password or parsed.fragment:
+        raise DistributionError("distribution URL must not contain credentials or a fragment")
+    if not allow_private_host:
+        _require_public_host(parsed.hostname)
+    request = Request(url, headers={"Accept": "application/json"})
+    try:
+        with urlopen(request, timeout=timeout_seconds) as response:  # noqa: S310
+            final = urlsplit(response.geturl())
+            if final.scheme != "https":
+                raise DistributionError("distribution redirect left HTTPS")
+            declared = response.headers.get("Content-Length")
+            if declared and int(declared) > maximum_bytes:
+                raise DistributionError("distribution download exceeds its size limit")
+            value = response.read(maximum_bytes + 1)
+    except DistributionError:
+        raise
+    except (OSError, ValueError) as exc:
+        raise DistributionError(f"distribution download failed: {exc}") from exc
+    if len(value) > maximum_bytes:
+        raise DistributionError("distribution download exceeds its size limit")
+    return value
+
+
+def decode_json_bytes(value: bytes, *, label: str) -> dict[str, Any]:
+    try:
+        payload = json.loads(value)
+    except (UnicodeDecodeError, json.JSONDecodeError) as exc:
+        raise DistributionError(f"{label} is not valid JSON") from exc
+    if not isinstance(payload, dict):
+        raise DistributionError(f"{label} root must be an object")
+    return payload
+
+
+def validate_manifest(
+    payload: Mapping[str, Any],
+    *,
+    expected_channel: str | None = None,
+    now: datetime | None = None,
+) -> None:
+    _exact_keys(
+        payload,
+        required={
+            "schema_version",
+            "channel",
+            "sequence",
+            "version",
+            "issued_at",
+            "expires_at",
+            "revoked",
+            "deployer",
+            "images",
+            "dependencies",
+            "composition",
+            "signatures",
+        },
+        label="distribution manifest",
+    )
+    if payload.get("schema_version") != "1":
+        raise DistributionError("unsupported distribution manifest schema_version")
+    channel = _token(payload.get("channel"), "channel", maximum=32, pattern=MODULE_ID)
+    if expected_channel is not None and channel != expected_channel:
+        raise DistributionError(
+            f"distribution channel is {channel!r}, expected {expected_channel!r}"
+        )
+    if isinstance(payload.get("sequence"), bool) or not isinstance(
+        payload.get("sequence"), int
+    ) or int(payload["sequence"]) < 1:
+        raise DistributionError("distribution sequence must be a positive integer")
+    _token(payload.get("version"), "version", maximum=128, pattern=TOKEN)
+    issued = _datetime(payload.get("issued_at"), "issued_at")
+    expires = _datetime(payload.get("expires_at"), "expires_at")
+    current = (now or datetime.now(UTC)).astimezone(UTC)
+    if expires <= issued:
+        raise DistributionError("distribution expiry must be after issuance")
+    if issued > current:
+        raise DistributionError("distribution is not valid yet")
+    if expires <= current:
+        raise DistributionError("distribution manifest has expired")
+    if payload.get("revoked") is not False:
+        raise DistributionError("distribution manifest is revoked")
+
+    deployer = _object(payload.get("deployer"), "deployer")
+    _exact_keys(deployer, required={"url", "sha256"}, label="deployer")
+    _https_url(deployer.get("url"), "deployer.url")
+    _sha256(deployer.get("sha256"), "deployer.sha256")
+
+    images = _object(payload.get("images"), "images")
+    if set(images) != {"api", "web"}:
+        raise DistributionError("images must contain exactly api and web")
+    for name in ("api", "web"):
+        _validate_image(_object(images[name], f"images.{name}"), f"images.{name}")
+
+    dependencies = _object(payload.get("dependencies"), "dependencies")
+    if not dependencies:
+        raise DistributionError("dependencies must not be empty")
+    for name, reference in dependencies.items():
+        if MODULE_ID.fullmatch(str(name)) is None:
+            raise DistributionError(f"invalid dependency name: {name!r}")
+        _digest_image(reference, f"dependencies.{name}")
+
+    composition = _object(payload.get("composition"), "composition")
+    _exact_keys(
+        composition,
+        required={"sha256", "module_ids", "packages"},
+        label="composition",
+    )
+    _sha256(composition.get("sha256"), "composition.sha256")
+    module_ids = _string_array(composition.get("module_ids"), "module_ids")
+    if any(MODULE_ID.fullmatch(item) is None for item in module_ids):
+        raise DistributionError("composition.module_ids contains an invalid id")
+    packages = composition.get("packages")
+    if not isinstance(packages, list) or not packages:
+        raise DistributionError("composition.packages must be a non-empty array")
+    seen_packages: set[str] = set()
+    for index, item in enumerate(packages):
+        package = _object(item, f"composition.packages[{index}]")
+        _exact_keys(
+            package,
+            required={"name", "version", "wheel_sha256"},
+            label=f"composition.packages[{index}]",
+        )
+        name = _token(
+            package.get("name"),
+            f"composition.packages[{index}].name",
+            maximum=128,
+            pattern=re.compile(r"^[a-z0-9]+(?:-[a-z0-9]+)*$"),
+        )
+        if name in seen_packages:
+            raise DistributionError("composition contains duplicate packages")
+        seen_packages.add(name)
+        _token(
+            package.get("version"),
+            f"composition.packages[{index}].version",
+            maximum=128,
+            pattern=TOKEN,
+        )
+        _sha256(
+            package.get("wheel_sha256"),
+            f"composition.packages[{index}].wheel_sha256",
+        )
+    signatures = payload.get("signatures")
+    if not isinstance(signatures, list) or not signatures:
+        raise DistributionError("distribution manifest has no signatures")
+    seen_signatures: set[str] = set()
+    for index, item in enumerate(signatures):
+        signature = _object(item, f"signatures[{index}]")
+        _exact_keys(
+            signature,
+            required={"key_id", "algorithm", "value"},
+            label=f"signatures[{index}]",
+        )
+        key_id = _token(
+            signature.get("key_id"),
+            f"signatures[{index}].key_id",
+            maximum=128,
+            pattern=KEY_ID,
+        )
+        if key_id in seen_signatures:
+            raise DistributionError("distribution contains duplicate signatures")
+        seen_signatures.add(key_id)
+        if signature.get("algorithm") != "ed25519":
+            raise DistributionError("distribution signature algorithm must be ed25519")
+        _signature_bytes(signature.get("value"), f"signatures[{index}].value")
+
+
+def verify_manifest(
+    payload: Mapping[str, Any],
+    keyring: Mapping[str, Any],
+    *,
+    expected_channel: str | None = None,
+    now: datetime | None = None,
+    openssl: str = "openssl",
+) -> str:
+    current = (now or datetime.now(UTC)).astimezone(UTC)
+    validate_manifest(payload, expected_channel=expected_channel, now=current)
+    keys = _trusted_keys(keyring, now=current)
+    signed = canonical_signed_payload(payload)
+    failures: list[str] = []
+    for item in payload["signatures"]:
+        key_id = str(item["key_id"])
+        public_key = keys.get(key_id)
+        if public_key is None:
+            continue
+        signature = _signature_bytes(item["value"], "signature.value")
+        try:
+            _openssl_verify(
+                signed,
+                signature,
+                public_key,
+                openssl=openssl,
+            )
+        except DistributionError as exc:
+            failures.append(f"{key_id}: {exc}")
+            continue
+        return key_id
+    detail = "; ".join(failures) if failures else "no signature used an active trusted key"
+    raise DistributionError(f"distribution signature verification failed: {detail}")
+
+
+def verify_manifest_binding(
+    payload: Mapping[str, Any],
+    *,
+    channel: str,
+    version: str,
+    api_image: str,
+    web_image: str,
+    enabled_modules: tuple[str, ...],
+    composition_sha256: str,
+    dependencies: Mapping[str, str],
+) -> None:
+    if payload.get("channel") != channel or payload.get("version") != version:
+        raise DistributionError("stored manifest does not match release channel/version")
+    images = _object(payload.get("images"), "images")
+    if _object(images.get("api"), "images.api").get("index") != api_image:
+        raise DistributionError("stored manifest does not match API image")
+    if _object(images.get("web"), "images.web").get("index") != web_image:
+        raise DistributionError("stored manifest does not match Web image")
+    composition = _object(payload.get("composition"), "composition")
+    if composition.get("sha256") != composition_sha256:
+        raise DistributionError("stored manifest composition digest does not match")
+    available_modules = set(_string_array(composition.get("module_ids"), "module_ids"))
+    missing = sorted(set(enabled_modules) - available_modules)
+    if missing:
+        raise DistributionError(
+            "enabled modules are absent from runtime composition: " + ", ".join(missing)
+        )
+    manifest_dependencies = _object(payload.get("dependencies"), "dependencies")
+    for name, reference in dependencies.items():
+        if manifest_dependencies.get(name) != reference:
+            raise DistributionError(
+                f"stored manifest does not match dependency image {name!r}"
+            )
+
+
+def verify_offline_image_index(
+    index: Mapping[str, Any],
+    *,
+    root: Path,
+    expected_references: tuple[str, ...],
+) -> tuple[Path, ...]:
+    _exact_keys(index, required={"schema_version", "images"}, label="offline index")
+    if index.get("schema_version") != "1":
+        raise DistributionError("unsupported offline image index schema")
+    images = index.get("images")
+    if not isinstance(images, list):
+        raise DistributionError("offline image index images must be an array")
+    references: dict[str, Path] = {}
+    for item in images:
+        value = _object(item, "offline image")
+        _exact_keys(
+            value,
+            required={"reference", "archive", "sha256"},
+            label="offline image",
+        )
+        reference = _digest_image(value.get("reference"), "offline image reference")
+        archive_value = value.get("archive")
+        if not isinstance(archive_value, str) or not archive_value:
+            raise DistributionError("offline image archive must be a relative path")
+        archive_relative = Path(archive_value)
+        if archive_relative.is_absolute() or ".." in archive_relative.parts:
+            raise DistributionError("offline image archive must stay inside its bundle")
+        archive = root / archive_relative
+        if reference in references:
+            raise DistributionError("offline image index contains duplicate references")
+        if _sha256_regular_file(archive, maximum_bytes=MAX_OFFLINE_IMAGE_BYTES) != _sha256(
+            value.get("sha256"), "offline image sha256"
+        ):
+            raise DistributionError(f"offline image archive digest mismatch: {archive}")
+        references[reference] = archive
+    missing = sorted(set(expected_references) - set(references))
+    if missing:
+        raise DistributionError(
+            "offline image bundle is incomplete: " + ", ".join(missing)
+        )
+    return tuple(references[item] for item in expected_references)
+
+
+def file_sha256(path: Path, *, maximum_bytes: int = MAX_MANIFEST_BYTES) -> str:
+    return _sha256_regular_file(path, maximum_bytes=maximum_bytes)
+
+
+def _validate_image(value: Mapping[str, Any], label: str) -> None:
+    _exact_keys(
+        value,
+        required={"index", "platforms", "sbom", "provenance"},
+        label=label,
+    )
+    _digest_image(value.get("index"), f"{label}.index")
+    platforms = _object(value.get("platforms"), f"{label}.platforms")
+    if set(platforms) != set(PLATFORMS):
+        raise DistributionError(f"{label}.platforms must cover amd64 and arm64")
+    for platform, reference in platforms.items():
+        _digest_image(reference, f"{label}.platforms.{platform}")
+    _validate_artifact(_object(value.get("sbom"), f"{label}.sbom"), f"{label}.sbom")
+    _validate_artifact(
+        _object(value.get("provenance"), f"{label}.provenance"),
+        f"{label}.provenance",
+    )
+
+
+def _validate_artifact(value: Mapping[str, Any], label: str) -> None:
+    _exact_keys(value, required={"url", "sha256"}, label=label)
+    _https_url(value.get("url"), f"{label}.url")
+    _sha256(value.get("sha256"), f"{label}.sha256")
+
+
+def _trusted_keys(
+    keyring: Mapping[str, Any],
+    *,
+    now: datetime,
+) -> dict[str, str]:
+    _exact_keys(
+        keyring,
+        required={"schema_version", "purpose", "keys"},
+        label="distribution keyring",
+    )
+    if keyring.get("schema_version") != "1":
+        raise DistributionError("unsupported distribution keyring schema_version")
+    if keyring.get("purpose") != "govoplan-runtime-distribution":
+        raise DistributionError("distribution keyring has the wrong purpose")
+    values = keyring.get("keys")
+    if not isinstance(values, list) or not values:
+        raise DistributionError("distribution keyring contains no keys")
+    trusted: dict[str, str] = {}
+    for index, item in enumerate(values):
+        key = _object(item, f"keyring.keys[{index}]")
+        _exact_keys(
+            key,
+            required={
+                "key_id",
+                "algorithm",
+                "status",
+                "public_key_pem",
+                "not_before",
+                "expires_at",
+            },
+            label=f"keyring.keys[{index}]",
+        )
+        key_id = _token(
+            key.get("key_id"),
+            f"keyring.keys[{index}].key_id",
+            maximum=128,
+            pattern=KEY_ID,
+        )
+        if key_id in trusted:
+            raise DistributionError("distribution keyring contains duplicate key ids")
+        if key.get("algorithm") != "ed25519":
+            raise DistributionError("distribution key must use ed25519")
+        if key.get("status") not in {"active", "retired", "revoked"}:
+            raise DistributionError("distribution key has an invalid status")
+        not_before = _datetime(key.get("not_before"), "key.not_before")
+        expires = _datetime(key.get("expires_at"), "key.expires_at")
+        public_key = key.get("public_key_pem")
+        if (
+            not isinstance(public_key, str)
+            or len(public_key.encode("utf-8")) > 8192
+            or "BEGIN PUBLIC KEY" not in public_key
+        ):
+            raise DistributionError("distribution key has an invalid public key")
+        if key.get("status") == "active" and not_before <= now < expires:
+            trusted[key_id] = public_key
+    if not trusted:
+        raise DistributionError("distribution keyring has no currently active keys")
+    return trusted
+
+
+def _openssl_verify(
+    payload: bytes,
+    signature: bytes,
+    public_key: str,
+    *,
+    openssl: str,
+) -> None:
+    with tempfile.TemporaryDirectory(prefix="govoplan-distribution-verify-") as value:
+        root = Path(value)
+        payload_path = root / "payload.json"
+        signature_path = root / "signature.bin"
+        key_path = root / "public.pem"
+        payload_path.write_bytes(payload)
+        signature_path.write_bytes(signature)
+        key_path.write_text(public_key, encoding="utf-8")
+        try:
+            completed = subprocess.run(
+                [
+                    openssl,
+                    "pkeyutl",
+                    "-verify",
+                    "-pubin",
+                    "-inkey",
+                    str(key_path),
+                    "-rawin",
+                    "-in",
+                    str(payload_path),
+                    "-sigfile",
+                    str(signature_path),
+                ],
+                check=False,
+                capture_output=True,
+                text=True,
+                timeout=10,
+            )
+        except (OSError, subprocess.TimeoutExpired) as exc:
+            raise DistributionError("OpenSSL Ed25519 verifier is unavailable") from exc
+    if completed.returncode != 0:
+        raise DistributionError("Ed25519 signature is invalid")
+
+
+def _signature_bytes(value: object, label: str) -> bytes:
+    if not isinstance(value, str) or len(value) > 256:
+        raise DistributionError(f"{label} is invalid")
+    try:
+        decoded = base64.b64decode(value, validate=True)
+    except (ValueError, base64.binascii.Error) as exc:
+        raise DistributionError(f"{label} is not valid base64") from exc
+    if len(decoded) != 64:
+        raise DistributionError(f"{label} is not an Ed25519 signature")
+    return decoded
+
+
+def _require_public_host(hostname: str) -> None:
+    try:
+        addresses = {
+            value[4][0]
+            for value in socket.getaddrinfo(hostname, 443, type=socket.SOCK_STREAM)
+        }
+    except OSError as exc:
+        raise DistributionError(f"distribution host cannot be resolved: {hostname}") from exc
+    if not addresses:
+        raise DistributionError("distribution host resolved to no addresses")
+    for value in addresses:
+        address = ipaddress.ip_address(value)
+        if not address.is_global:
+            raise DistributionError("distribution host resolves to a non-public address")
+
+
+def _sha256_regular_file(path: Path, *, maximum_bytes: int) -> str:
+    flags = os.O_RDONLY | getattr(os, "O_NOFOLLOW", 0)
+    try:
+        descriptor = os.open(path, flags)
+    except OSError as exc:
+        raise DistributionError(f"cannot open immutable artifact: {path}") from exc
+    digest = hashlib.sha256()
+    try:
+        opened = os.fstat(descriptor)
+        if not stat.S_ISREG(opened.st_mode) or opened.st_size > maximum_bytes:
+            raise DistributionError(f"immutable artifact is invalid or too large: {path}")
+        while True:
+            chunk = os.read(descriptor, 1024 * 1024)
+            if not chunk:
+                break
+            digest.update(chunk)
+        final = os.fstat(descriptor)
+        if (opened.st_dev, opened.st_ino, opened.st_size, opened.st_mtime_ns) != (
+            final.st_dev,
+            final.st_ino,
+            final.st_size,
+            final.st_mtime_ns,
+        ):
+            raise DistributionError(f"immutable artifact changed while read: {path}")
+    finally:
+        os.close(descriptor)
+    return digest.hexdigest()
+
+
+def _object(value: object, label: str) -> dict[str, Any]:
+    if not isinstance(value, dict) or not all(isinstance(key, str) for key in value):
+        raise DistributionError(f"{label} must be an object")
+    return value
+
+
+def _exact_keys(
+    value: Mapping[str, Any],
+    *,
+    required: set[str],
+    label: str,
+) -> None:
+    missing = sorted(required - set(value))
+    extra = sorted(set(value) - required)
+    if missing or extra:
+        detail = []
+        if missing:
+            detail.append("missing " + ", ".join(missing))
+        if extra:
+            detail.append("unknown " + ", ".join(extra))
+        raise DistributionError(f"{label} has invalid fields: {'; '.join(detail)}")
+
+
+def _token(
+    value: object,
+    label: str,
+    *,
+    maximum: int,
+    pattern: re.Pattern[str],
+) -> str:
+    if not isinstance(value, str) or len(value) > maximum or pattern.fullmatch(value) is None:
+        raise DistributionError(f"{label} is invalid")
+    return value
+
+
+def _datetime(value: object, label: str) -> datetime:
+    if not isinstance(value, str) or len(value) > 64:
+        raise DistributionError(f"{label} must be an RFC3339 timestamp")
+    try:
+        parsed = datetime.fromisoformat(value.replace("Z", "+00:00"))
+    except ValueError as exc:
+        raise DistributionError(f"{label} must be an RFC3339 timestamp") from exc
+    if parsed.tzinfo is None:
+        raise DistributionError(f"{label} must include a timezone")
+    return parsed.astimezone(UTC)
+
+
+def _sha256(value: object, label: str) -> str:
+    if not isinstance(value, str) or SHA256.fullmatch(value) is None:
+        raise DistributionError(f"{label} must be a lowercase SHA-256 digest")
+    return value
+
+
+def _digest_image(value: object, label: str) -> str:
+    if not isinstance(value, str) or len(value) > 300 or DIGEST_IMAGE.fullmatch(value) is None:
+        raise DistributionError(f"{label} must be an OCI image pinned by sha256")
+    return value
+
+
+def _https_url(value: object, label: str) -> str:
+    if not isinstance(value, str) or len(value) > 2048:
+        raise DistributionError(f"{label} must be an HTTPS URL")
+    parsed = urlsplit(value)
+    if parsed.scheme != "https" or not parsed.netloc or parsed.username or parsed.password:
+        raise DistributionError(f"{label} must be an HTTPS URL without credentials")
+    return value
+
+
+def _string_array(value: object, label: str) -> tuple[str, ...]:
+    if (
+        not isinstance(value, list)
+        or len(value) > 1024
+        or any(not isinstance(item, str) for item in value)
+        or len(set(value)) != len(value)
+    ):
+        raise DistributionError(f"{label} must be an array of unique strings")
+    return tuple(value)
diff --git a/tools/deployment/govoplan_deploy/model.py b/tools/deployment/govoplan_deploy/model.py
index d10136f..3ad70d7 100644
--- a/tools/deployment/govoplan_deploy/model.py
+++ b/tools/deployment/govoplan_deploy/model.py
@@ -77,6 +77,9 @@ class ReleaseConfig:
     version: str
     manifest_url: str
     manifest_sha256: str
+    manifest_keyring_sha256: str
+    manifest_signature_key_id: str
+    composition_sha256: str
     api_image: str
     web_image: str
 
@@ -178,6 +181,9 @@ def default_spec(
             "version": version,
             "manifest_url": manifest_url,
             "manifest_sha256": manifest_sha256,
+            "manifest_keyring_sha256": "",
+            "manifest_signature_key_id": "",
+            "composition_sha256": "",
             "api_image": api_image,
             "web_image": web_image,
         },
@@ -314,6 +320,9 @@ def _release(raw: object) -> ReleaseConfig:
             "version",
             "manifest_url",
             "manifest_sha256",
+            "manifest_keyring_sha256",
+            "manifest_signature_key_id",
+            "composition_sha256",
             "api_image",
             "web_image",
         },
@@ -335,6 +344,27 @@ def _release(raw: object) -> ReleaseConfig:
         raise SpecError(
             "release.manifest_sha256 must be a lowercase SHA-256 hex digest"
         )
+    manifest_keyring_sha256 = _optional_string(
+        value, "manifest_keyring_sha256"
+    ).lower()
+    if manifest_keyring_sha256 and not SHA256_PATTERN.fullmatch(
+        manifest_keyring_sha256
+    ):
+        raise SpecError(
+            "release.manifest_keyring_sha256 must be a lowercase SHA-256 hex digest"
+        )
+    manifest_signature_key_id = _optional_string(
+        value, "manifest_signature_key_id"
+    )
+    if manifest_signature_key_id and not re.fullmatch(
+        r"[A-Za-z0-9][A-Za-z0-9._:-]{0,127}", manifest_signature_key_id
+    ):
+        raise SpecError("release.manifest_signature_key_id is invalid")
+    composition_sha256 = _optional_string(value, "composition_sha256").lower()
+    if composition_sha256 and not SHA256_PATTERN.fullmatch(composition_sha256):
+        raise SpecError(
+            "release.composition_sha256 must be a lowercase SHA-256 hex digest"
+        )
     api_image = _image(_string(value, "api_image"), "release.api_image")
     web_image = _image(_string(value, "web_image"), "release.web_image")
     return ReleaseConfig(
@@ -342,6 +372,9 @@ def _release(raw: object) -> ReleaseConfig:
         version=version,
         manifest_url=manifest_url,
         manifest_sha256=manifest_sha256,
+        manifest_keyring_sha256=manifest_keyring_sha256,
+        manifest_signature_key_id=manifest_signature_key_id,
+        composition_sha256=composition_sha256,
         api_image=api_image,
         web_image=web_image,
     )
diff --git a/tools/deployment/govoplan_deploy/planning.py b/tools/deployment/govoplan_deploy/planning.py
index 744ee0b..5db2ff1 100644
--- a/tools/deployment/govoplan_deploy/planning.py
+++ b/tools/deployment/govoplan_deploy/planning.py
@@ -22,6 +22,15 @@ from .bundle import (
     render_compose,
     service_names,
 )
+from .distribution import (
+    MAX_KEYRING_BYTES,
+    MAX_MANIFEST_BYTES,
+    DistributionError,
+    file_sha256,
+    load_bounded_json,
+    verify_manifest,
+    verify_manifest_binding,
+)
 from .model import (
     InstallationSpec,
     image_is_digest_pinned,
@@ -212,40 +221,7 @@ def static_checks(spec: InstallationSpec, paths: BundlePaths) -> tuple[Check, ..
                 )
             )
 
-    if spec.release.manifest_url and spec.release.manifest_sha256:
-        checks.append(
-            Check(
-                "release.manifest",
-                "ok",
-                "A distribution manifest URL and expected digest are recorded.",
-            )
-        )
-    else:
-        checks.append(
-            Check(
-                "release.manifest",
-                "error" if spec.profile == "self-hosted" else "warning",
-                "No verified distribution manifest is recorded.",
-                "Use a published signed distribution manifest for self-hosted apply.",
-            )
-        )
-    if spec.profile == "self-hosted":
-        checks.append(
-            Check(
-                "release.signature_verification",
-                "error",
-                "Signed distribution-manifest verification is not implemented in the deployer yet.",
-                "Use the published verifier/bootstrap slice before a production apply.",
-            )
-        )
-    checks.append(
-        Check(
-            "modules.image_composition",
-            "error" if spec.enabled_modules else "warning",
-            "The selected module set is not yet verified against image package contents.",
-            "Use the signed distribution composition evidence before production apply.",
-        )
-    )
+    checks.extend(_distribution_checks(spec, paths))
 
     values = read_env(paths.env)
     required = {"MASTER_KEY_B64", "DATABASE_URL"}
@@ -364,6 +340,130 @@ def static_checks(spec: InstallationSpec, paths: BundlePaths) -> tuple[Check, ..
     return tuple(checks)
 
 
+def _distribution_checks(
+    spec: InstallationSpec,
+    paths: BundlePaths,
+) -> tuple[Check, ...]:
+    blocking_level = "error" if spec.profile == "self-hosted" else "warning"
+    if not (
+        spec.release.manifest_sha256
+        and spec.release.manifest_keyring_sha256
+        and spec.release.manifest_signature_key_id
+        and spec.release.composition_sha256
+        and paths.manifest.exists()
+        and paths.keyring.exists()
+    ):
+        return (
+            Check(
+                "release.manifest",
+                blocking_level,
+                "No locally verified runtime distribution is recorded.",
+                "Run govoplan-deploy verify-release --adopt with an independently trusted keyring.",
+            ),
+            Check(
+                "release.signature_verification",
+                blocking_level,
+                "Runtime distribution signature evidence is unavailable.",
+                "Install and verify the signed distribution before apply.",
+            ),
+            Check(
+                "modules.image_composition",
+                blocking_level,
+                "Enabled modules are not bound to image composition evidence.",
+                "Adopt a distribution whose composition contains every enabled module.",
+            ),
+        )
+    try:
+        manifest_digest = file_sha256(
+            paths.manifest,
+            maximum_bytes=MAX_MANIFEST_BYTES,
+        )
+        if manifest_digest != spec.release.manifest_sha256:
+            raise DistributionError("stored manifest digest does not match installation")
+        keyring_digest = file_sha256(
+            paths.keyring,
+            maximum_bytes=MAX_KEYRING_BYTES,
+        )
+        if keyring_digest != spec.release.manifest_keyring_sha256:
+            raise DistributionError("stored keyring digest does not match installation")
+        manifest = load_bounded_json(
+            paths.manifest,
+            maximum_bytes=MAX_MANIFEST_BYTES,
+        )
+        keyring = load_bounded_json(
+            paths.keyring,
+            maximum_bytes=MAX_KEYRING_BYTES,
+        )
+        key_id = verify_manifest(
+            manifest,
+            keyring,
+            expected_channel=spec.release.channel,
+        )
+        if key_id != spec.release.manifest_signature_key_id:
+            raise DistributionError("verified signature key does not match installation")
+        verify_manifest_binding(
+            manifest,
+            channel=spec.release.channel,
+            version=spec.release.version,
+            api_image=spec.release.api_image,
+            web_image=spec.release.web_image,
+            enabled_modules=spec.enabled_modules,
+            composition_sha256=spec.release.composition_sha256,
+            dependencies=_selected_dependency_images(spec),
+        )
+    except (DistributionError, OSError) as exc:
+        return (
+            Check(
+                "release.manifest",
+                blocking_level,
+                f"Runtime distribution verification failed: {exc}",
+                "Re-adopt an unexpired, non-revoked manifest from a trusted release key.",
+            ),
+            Check(
+                "release.signature_verification",
+                blocking_level,
+                "Runtime distribution signature is not trusted.",
+                "Correct the manifest/keyring binding before apply.",
+            ),
+            Check(
+                "modules.image_composition",
+                blocking_level,
+                "Runtime image composition is not trusted.",
+                "Correct the signed composition binding before apply.",
+            ),
+        )
+    return (
+        Check(
+            "release.manifest",
+            "ok",
+            "Stored runtime distribution matches its independently pinned digest.",
+        ),
+        Check(
+            "release.signature_verification",
+            "ok",
+            f"Runtime distribution is signed by trusted key {key_id}.",
+        ),
+        Check(
+            "modules.image_composition",
+            "ok",
+            "Every enabled module is present in signed image composition evidence.",
+        ),
+    )
+
+
+def _selected_dependency_images(spec: InstallationSpec) -> dict[str, str]:
+    values = {"load_balancer": spec.components.load_balancer.image}
+    if spec.components.postgres.mode == "managed":
+        values["postgres"] = spec.components.postgres.image
+    if spec.components.redis.mode == "managed":
+        values["redis"] = spec.components.redis.image
+    if spec.components.mail.mode == "test-mail":
+        values["test_mail"] = spec.components.mail.image
+    if spec.components.storage.mode == "garage":
+        values["garage"] = spec.components.storage.image
+    return values
+
+
 def host_checks(
     spec: InstallationSpec,
     paths: BundlePaths,
diff --git a/tools/release/finalize-runtime-distribution.py b/tools/release/finalize-runtime-distribution.py
new file mode 100644
index 0000000..b2fbe42
--- /dev/null
+++ b/tools/release/finalize-runtime-distribution.py
@@ -0,0 +1,282 @@
+#!/usr/bin/env python3
+"""Create runtime SBOM, provenance, and an unsigned distribution descriptor."""
+
+from __future__ import annotations
+
+import argparse
+from datetime import UTC, datetime, timedelta
+import hashlib
+import json
+from pathlib import Path
+import re
+import sys
+from typing import Any
+from urllib.parse import urlsplit
+import uuid
+
+
+SHA256 = re.compile(r"^[0-9a-f]{64}$")
+DIGEST_IMAGE = re.compile(r"^[^@\s]+@sha256:[0-9a-f]{64}$")
+
+
+def build_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--composition", type=Path, required=True)
+    parser.add_argument("--api-metadata", type=Path, required=True)
+    parser.add_argument("--web-metadata", type=Path, required=True)
+    parser.add_argument("--deployer", type=Path, required=True)
+    parser.add_argument("--deployer-url", required=True)
+    parser.add_argument("--artifact-base-url", required=True)
+    parser.add_argument("--source-commit", required=True)
+    parser.add_argument("--version", required=True)
+    parser.add_argument("--channel", default="stable")
+    parser.add_argument("--sequence", type=int, required=True)
+    parser.add_argument("--expires-days", type=int, default=90)
+    parser.add_argument(
+        "--dependency",
+        action="append",
+        default=[],
+        metavar="NAME=IMAGE@SHA256",
+    )
+    parser.add_argument("--output-directory", type=Path, required=True)
+    parser.add_argument("--descriptor", type=Path, required=True)
+    return parser
+
+
+def finalize(args: argparse.Namespace) -> dict[str, Any]:
+    composition = _json_object(args.composition)
+    api = _image_metadata(_json_object(args.api_metadata), "api")
+    web = _image_metadata(_json_object(args.web_metadata), "web")
+    dependencies = dict(_dependency(value) for value in args.dependency)
+    if not dependencies:
+        raise ValueError("at least one --dependency is required")
+    _https_url(args.deployer_url, "deployer URL")
+    artifact_base = _https_url(args.artifact_base_url, "artifact base URL").rstrip("/")
+    if args.sequence < 1 or not 1 <= args.expires_days <= 365:
+        raise ValueError("sequence and expiry window are out of bounds")
+    output = args.output_directory.expanduser().resolve()
+    output.mkdir(parents=True, exist_ok=True)
+
+    api_sbom = _api_sbom(composition, version=args.version)
+    web_sbom = _web_sbom(composition, version=args.version)
+    api_provenance = _provenance(
+        subject=api["index"],
+        source_commit=args.source_commit,
+        composition=composition,
+    )
+    web_provenance = _provenance(
+        subject=web["index"],
+        source_commit=args.source_commit,
+        composition=composition,
+    )
+    artifact_values = {
+        "api-sbom.cdx.json": api_sbom,
+        "web-sbom.cdx.json": web_sbom,
+        "api-provenance.json": api_provenance,
+        "web-provenance.json": web_provenance,
+    }
+    artifacts: dict[str, dict[str, str]] = {}
+    for filename, value in artifact_values.items():
+        path = output / filename
+        encoded = _canonical_json(value)
+        path.write_bytes(encoded)
+        artifacts[filename] = {
+            "url": f"{artifact_base}/{filename}",
+            "sha256": hashlib.sha256(encoded).hexdigest(),
+        }
+    composition_encoded = _canonical_json(composition)
+    packages = _manifest_packages(composition)
+    issued = datetime.now(UTC).replace(microsecond=0)
+    descriptor: dict[str, Any] = {
+        "schema_version": "1",
+        "channel": args.channel,
+        "sequence": args.sequence,
+        "version": args.version,
+        "issued_at": issued.isoformat(),
+        "expires_at": (issued + timedelta(days=args.expires_days)).isoformat(),
+        "revoked": False,
+        "deployer": {
+            "url": args.deployer_url,
+            "sha256": _sha256_file(args.deployer),
+        },
+        "images": {
+            "api": {
+                **api,
+                "sbom": artifacts["api-sbom.cdx.json"],
+                "provenance": artifacts["api-provenance.json"],
+            },
+            "web": {
+                **web,
+                "sbom": artifacts["web-sbom.cdx.json"],
+                "provenance": artifacts["web-provenance.json"],
+            },
+        },
+        "dependencies": dict(sorted(dependencies.items())),
+        "composition": {
+            "sha256": hashlib.sha256(composition_encoded).hexdigest(),
+            "module_ids": list(composition["python"]["module_ids"]),
+            "packages": packages,
+        },
+    }
+    args.descriptor.parent.mkdir(parents=True, exist_ok=True)
+    args.descriptor.write_bytes(_canonical_json(descriptor))
+    return descriptor
+
+
+def _api_sbom(composition: dict[str, Any], *, version: str) -> dict[str, Any]:
+    components = []
+    for package in composition["python"]["packages"]:
+        components.append(
+            {
+                "type": "library",
+                "name": package["package"],
+                "version": package["version"],
+                "hashes": [{"alg": "SHA-256", "content": package["sha256"]}],
+                "purl": f"pkg:pypi/{package['package']}@{package['version']}",
+            }
+        )
+    return {
+        "bomFormat": "CycloneDX",
+        "specVersion": "1.6",
+        "serialNumber": f"urn:uuid:{uuid.uuid5(uuid.NAMESPACE_URL, 'govoplan-api:' + version)}",
+        "version": 1,
+        "metadata": {"component": {"type": "application", "name": "govoplan-api", "version": version}},
+        "components": components,
+    }
+
+
+def _web_sbom(composition: dict[str, Any], *, version: str) -> dict[str, Any]:
+    return {
+        "bomFormat": "CycloneDX",
+        "specVersion": "1.6",
+        "serialNumber": f"urn:uuid:{uuid.uuid5(uuid.NAMESPACE_URL, 'govoplan-web:' + version)}",
+        "version": 1,
+        "metadata": {"component": {"type": "application", "name": "govoplan-web", "version": version}},
+        "components": [
+            {
+                "type": "file",
+                "name": "govoplan-web-dist",
+                "version": version,
+                "hashes": [
+                    {
+                        "alg": "SHA-256",
+                        "content": composition["web"]["sha256"],
+                    }
+                ],
+            }
+        ],
+    }
+
+
+def _provenance(
+    *,
+    subject: str,
+    source_commit: str,
+    composition: dict[str, Any],
+) -> dict[str, Any]:
+    digest = subject.rsplit("@sha256:", 1)[1]
+    return {
+        "_type": "https://in-toto.io/Statement/v1",
+        "subject": [{"name": subject.split("@", 1)[0], "digest": {"sha256": digest}}],
+        "predicateType": "https://slsa.dev/provenance/v1",
+        "predicate": {
+            "buildDefinition": {
+                "buildType": "https://govoplan.add-ideas.de/build/runtime-oci/v1",
+                "externalParameters": {
+                    "source_commit": source_commit,
+                    "network_free_image_assembly": True,
+                },
+                "resolvedDependencies": [
+                    {
+                        "uri": "govoplan:runtime-composition",
+                        "digest": {
+                            "sha256": hashlib.sha256(_canonical_json(composition)).hexdigest()
+                        },
+                    }
+                ],
+            },
+            "runDetails": {
+                "builder": {"id": "https://git.add-ideas.de/GovOPlaN/govoplan/actions"},
+                "metadata": {"invocationId": source_commit},
+            },
+        },
+    }
+
+
+def _manifest_packages(composition: dict[str, Any]) -> list[dict[str, str]]:
+    values = []
+    for package in composition["python"]["packages"]:
+        values.append(
+            {
+                "name": str(package["package"]),
+                "version": str(package["version"]),
+                "wheel_sha256": str(package["sha256"]),
+            }
+        )
+    return sorted(values, key=lambda item: item["name"])
+
+
+def _image_metadata(value: dict[str, Any], label: str) -> dict[str, Any]:
+    if set(value) != {"index", "platforms"}:
+        raise ValueError(f"{label} image metadata has invalid fields")
+    if not isinstance(value["index"], str) or DIGEST_IMAGE.fullmatch(value["index"]) is None:
+        raise ValueError(f"{label} index is not digest-pinned")
+    platforms = value["platforms"]
+    if not isinstance(platforms, dict) or set(platforms) != {"linux/amd64", "linux/arm64"}:
+        raise ValueError(f"{label} image does not cover amd64 and arm64")
+    if any(not isinstance(item, str) or DIGEST_IMAGE.fullmatch(item) is None for item in platforms.values()):
+        raise ValueError(f"{label} platform image is not digest-pinned")
+    return {"index": value["index"], "platforms": dict(sorted(platforms.items()))}
+
+
+def _dependency(value: str) -> tuple[str, str]:
+    if "=" not in value:
+        raise ValueError("--dependency must use NAME=IMAGE@SHA256")
+    name, reference = value.split("=", 1)
+    if re.fullmatch(r"[a-z][a-z0-9_]{1,63}", name) is None:
+        raise ValueError(f"invalid dependency name: {name!r}")
+    if DIGEST_IMAGE.fullmatch(reference) is None:
+        raise ValueError(f"dependency {name!r} is not digest-pinned")
+    return name, reference
+
+
+def _json_object(path: Path) -> dict[str, Any]:
+    value = json.loads(path.read_text(encoding="utf-8"))
+    if not isinstance(value, dict):
+        raise ValueError(f"JSON root must be an object: {path}")
+    return value
+
+
+def _https_url(value: str, label: str) -> str:
+    parsed = urlsplit(value)
+    if parsed.scheme != "https" or not parsed.netloc or parsed.username or parsed.password:
+        raise ValueError(f"{label} must be an HTTPS URL without credentials")
+    return value
+
+
+def _sha256_file(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as handle:
+        for chunk in iter(lambda: handle.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def _canonical_json(value: object) -> bytes:
+    return (json.dumps(value, indent=2, sort_keys=True) + "\n").encode("utf-8")
+
+
+def main() -> int:
+    args = build_parser().parse_args()
+    try:
+        finalize(args)
+    except (KeyError, OSError, TypeError, ValueError, json.JSONDecodeError) as exc:
+        print(f"error: {exc}", file=sys.stderr)
+        return 1
+    print(f"Runtime release evidence written below {args.output_directory}")
+    print(f"Unsigned descriptor written to {args.descriptor}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/tools/release/generate-runtime-distribution.py b/tools/release/generate-runtime-distribution.py
new file mode 100644
index 0000000..e6de0ae
--- /dev/null
+++ b/tools/release/generate-runtime-distribution.py
@@ -0,0 +1,110 @@
+#!/usr/bin/env python3
+"""Validate and sign a GovOPlaN OCI runtime distribution manifest."""
+
+from __future__ import annotations
+
+import argparse
+import base64
+import json
+from pathlib import Path
+import sys
+
+from cryptography.hazmat.primitives import serialization
+from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
+
+
+META_ROOT = Path(__file__).resolve().parents[2]
+sys.path.insert(0, str(META_ROOT / "tools" / "deployment"))
+
+from govoplan_deploy.distribution import (  # noqa: E402
+    DistributionError,
+    canonical_json,
+    canonical_signed_payload,
+    validate_manifest,
+)
+
+
+def build_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--descriptor", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    parser.add_argument(
+        "--signing-key",
+        action="append",
+        default=[],
+        metavar="KEY_ID=PRIVATE_PEM",
+        required=True,
+    )
+    return parser
+
+
+def sign_manifest(
+    descriptor: dict[str, object],
+    signing_keys: tuple[tuple[str, Path], ...],
+) -> dict[str, object]:
+    payload = dict(descriptor)
+    payload["signatures"] = [
+        _signature(payload, key_id=key_id, path=path)
+        for key_id, path in signing_keys
+    ]
+    validate_manifest(payload)
+    return payload
+
+
+def _signature(
+    payload: dict[str, object],
+    *,
+    key_id: str,
+    path: Path,
+) -> dict[str, str]:
+    try:
+        key = serialization.load_pem_private_key(path.read_bytes(), password=None)
+    except (OSError, ValueError, TypeError) as exc:
+        raise DistributionError(f"cannot load signing key {key_id!r}") from exc
+    if not isinstance(key, Ed25519PrivateKey):
+        raise DistributionError(f"signing key {key_id!r} is not Ed25519")
+    return {
+        "key_id": key_id,
+        "algorithm": "ed25519",
+        "value": base64.b64encode(key.sign(canonical_signed_payload(payload))).decode(
+            "ascii"
+        ),
+    }
+
+
+def _parse_signing_key(value: str) -> tuple[str, Path]:
+    if "=" not in value:
+        raise DistributionError("--signing-key must use KEY_ID=PRIVATE_PEM")
+    key_id, raw_path = value.split("=", 1)
+    if not key_id or not raw_path:
+        raise DistributionError("--signing-key must use KEY_ID=PRIVATE_PEM")
+    return key_id, Path(raw_path).expanduser().resolve()
+
+
+def main() -> int:
+    args = build_parser().parse_args()
+    try:
+        descriptor = json.loads(args.descriptor.read_text(encoding="utf-8"))
+        if not isinstance(descriptor, dict):
+            raise DistributionError("descriptor root must be an object")
+        if "signatures" in descriptor:
+            raise DistributionError("descriptor must not contain signatures")
+        payload = sign_manifest(
+            descriptor,
+            tuple(_parse_signing_key(value) for value in args.signing_key),
+        )
+        encoded = canonical_json(payload)
+        args.output.parent.mkdir(parents=True, exist_ok=True)
+        temporary = args.output.with_suffix(args.output.suffix + ".tmp")
+        temporary.write_bytes(encoded)
+        temporary.chmod(0o644)
+        temporary.replace(args.output)
+    except (DistributionError, OSError, ValueError, json.JSONDecodeError) as exc:
+        print(f"error: {exc}", file=sys.stderr)
+        return 1
+    print(f"Runtime distribution manifest written to {args.output}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/tools/release/prepare-runtime-context.py b/tools/release/prepare-runtime-context.py
new file mode 100644
index 0000000..54cfe68
--- /dev/null
+++ b/tools/release/prepare-runtime-context.py
@@ -0,0 +1,337 @@
+#!/usr/bin/env python3
+"""Assemble a deterministic, network-free GovOPlaN OCI build context."""
+
+from __future__ import annotations
+
+import argparse
+import configparser
+from email.parser import BytesParser
+from email.policy import compat32
+import hashlib
+import json
+import os
+from pathlib import Path, PurePosixPath
+import re
+import shutil
+import stat
+import zipfile
+
+
+NORMALIZED_PACKAGE = re.compile(r"^[a-z0-9]+(?:-[a-z0-9]+)*$")
+VERSION = re.compile(r"^[A-Za-z0-9][A-Za-z0-9._+!-]{0,127}$")
+MAX_WHEELS = 512
+MAX_WHEEL_BYTES = 512 * 1024 * 1024
+MAX_WEB_FILES = 100_000
+MAX_WEB_BYTES = 2 * 1024 * 1024 * 1024
+
+
+class ContextError(ValueError):
+    """The release inputs cannot form an immutable runtime context."""
+
+
+def build_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--wheelhouse", type=Path, required=True)
+    parser.add_argument("--web-dist", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    parser.add_argument("--required-module", action="append", default=[])
+    parser.add_argument(
+        "--source-date-epoch",
+        type=int,
+        default=int(os.environ.get("SOURCE_DATE_EPOCH", "0") or 0),
+    )
+    return parser
+
+
+def prepare_context(
+    *,
+    wheelhouse: Path,
+    web_dist: Path,
+    output: Path,
+    required_modules: tuple[str, ...] = (),
+    source_date_epoch: int = 0,
+) -> dict[str, object]:
+    source_wheels = _regular_files(wheelhouse, suffix=".whl", maximum=MAX_WHEELS)
+    if not source_wheels:
+        raise ContextError("wheelhouse contains no wheel artifacts")
+    if output.exists() and any(output.iterdir()):
+        raise ContextError("output directory must be absent or empty")
+    output.mkdir(parents=True, exist_ok=True)
+    target_wheels = output / "wheelhouse"
+    target_web = output / "web-dist"
+    target_wheels.mkdir(mode=0o755)
+
+    packages: list[dict[str, object]] = []
+    govoplan_wheel_rows: list[dict[str, object]] = []
+    roots: list[tuple[str, str]] = []
+    module_ids: set[str] = set()
+    seen_packages: set[str] = set()
+    wheel_rows: list[dict[str, object]] = []
+    for source in source_wheels:
+        if source.stat().st_size > MAX_WHEEL_BYTES:
+            raise ContextError(f"wheel exceeds size limit: {source.name}")
+        identity = inspect_wheel(source)
+        package_name = str(identity["package"])
+        if package_name in seen_packages:
+            raise ContextError(f"duplicate wheel distribution: {package_name}")
+        seen_packages.add(package_name)
+        target = target_wheels / source.name
+        _copy_regular(source, target, source_date_epoch=source_date_epoch)
+        row = {
+            "filename": source.name,
+            "sha256": _sha256_file(target),
+            "size": target.stat().st_size,
+        }
+        wheel_rows.append(row)
+        if package_name.startswith("govoplan-"):
+            package_modules = tuple(str(item) for item in identity["module_ids"])
+            module_ids.update(package_modules)
+            package = {
+                **row,
+                "package": package_name,
+                "version": identity["version"],
+                "module_ids": list(package_modules),
+            }
+            packages.append(package)
+            govoplan_wheel_rows.append(row)
+            root = (
+                f"{package_name}[server]"
+                if package_name == "govoplan-core"
+                else package_name
+            )
+            roots.append((root, str(identity["version"])))
+
+    if not any(package["package"] == "govoplan-core" for package in packages):
+        raise ContextError("wheelhouse does not contain govoplan-core")
+    missing_modules = sorted(set(required_modules) - module_ids)
+    if missing_modules:
+        raise ContextError(
+            "runtime composition is missing required modules: "
+            + ", ".join(missing_modules)
+        )
+    requirements = "".join(
+        f"{package}=={version}\n" for package, version in sorted(roots)
+    )
+    _write_regular(
+        output / "requirements-runtime.txt",
+        requirements.encode("utf-8"),
+        source_date_epoch=source_date_epoch,
+    )
+
+    web_rows = _copy_web_tree(
+        web_dist,
+        target_web,
+        source_date_epoch=source_date_epoch,
+    )
+    composition: dict[str, object] = {
+        "schema_version": "1",
+        "python": {
+            "packages": sorted(packages, key=lambda item: str(item["package"])),
+            "module_ids": sorted(module_ids),
+            "wheelhouse_sha256": _rows_digest(govoplan_wheel_rows),
+            "wheel_count": len(govoplan_wheel_rows),
+        },
+        "web": {
+            "sha256": _rows_digest(web_rows),
+            "file_count": len(web_rows),
+        },
+    }
+    encoded = (json.dumps(composition, indent=2, sort_keys=True) + "\n").encode(
+        "utf-8"
+    )
+    _write_regular(
+        output / "composition.json",
+        encoded,
+        source_date_epoch=source_date_epoch,
+    )
+    _write_regular(
+        target_web / ".well-known" / "govoplan-composition.json",
+        encoded,
+        source_date_epoch=source_date_epoch,
+    )
+    _copy_regular(
+        Path(__file__).resolve().parent / "runtime" / "nginx.conf",
+        output / "nginx.conf",
+        source_date_epoch=source_date_epoch,
+    )
+    return composition
+
+
+def inspect_wheel(path: Path) -> dict[str, object]:
+    flags = os.O_RDONLY | getattr(os, "O_NOFOLLOW", 0)
+    try:
+        descriptor = os.open(path, flags)
+    except OSError as exc:
+        raise ContextError(f"wheel cannot be opened safely: {path.name}") from exc
+    try:
+        opened = os.fstat(descriptor)
+        if not stat.S_ISREG(opened.st_mode):
+            raise ContextError(f"wheel is not a regular file: {path.name}")
+        with os.fdopen(os.dup(descriptor), "rb") as handle:
+            with zipfile.ZipFile(handle) as archive:
+                metadata = [
+                    member
+                    for member in archive.infolist()
+                    if PurePosixPath(member.filename).name == "METADATA"
+                    and PurePosixPath(member.filename).parent.name.endswith(
+                        ".dist-info"
+                    )
+                ]
+                if len(metadata) != 1:
+                    raise ContextError(
+                        f"wheel must contain one METADATA file: {path.name}"
+                    )
+                parsed = BytesParser(policy=compat32).parsebytes(
+                    archive.read(metadata[0])
+                )
+                package = _normalize_package(str(parsed.get("Name") or ""))
+                version = str(parsed.get("Version") or "").strip()
+                if VERSION.fullmatch(version) is None:
+                    raise ContextError(f"wheel has invalid version: {path.name}")
+                entry_points_name = (
+                    PurePosixPath(metadata[0].filename).parent / "entry_points.txt"
+                ).as_posix()
+                module_ids: tuple[str, ...] = ()
+                if entry_points_name in archive.namelist():
+                    module_ids = _module_entry_points(
+                        archive.read(entry_points_name).decode("utf-8")
+                    )
+        final = os.fstat(descriptor)
+        if (opened.st_dev, opened.st_ino, opened.st_size, opened.st_mtime_ns) != (
+            final.st_dev,
+            final.st_ino,
+            final.st_size,
+            final.st_mtime_ns,
+        ):
+            raise ContextError(f"wheel changed while inspected: {path.name}")
+    except (OSError, RuntimeError, zipfile.BadZipFile) as exc:
+        if isinstance(exc, ContextError):
+            raise
+        raise ContextError(f"wheel is not a readable archive: {path.name}") from exc
+    finally:
+        os.close(descriptor)
+    return {"package": package, "version": version, "module_ids": module_ids}
+
+
+def _module_entry_points(value: str) -> tuple[str, ...]:
+    parser = configparser.ConfigParser(interpolation=None, strict=True)
+    try:
+        parser.read_string(value)
+    except configparser.Error as exc:
+        raise ContextError("wheel entry_points.txt is malformed") from exc
+    if not parser.has_section("govoplan.modules"):
+        return ()
+    values = tuple(sorted(parser.options("govoplan.modules")))
+    for item in values:
+        if re.fullmatch(r"[a-z][a-z0-9_]{1,63}", item) is None:
+            raise ContextError(f"wheel has invalid module entry point: {item!r}")
+    return values
+
+
+def _normalize_package(value: str) -> str:
+    normalized = re.sub(r"[-_.]+", "-", value.strip().lower())
+    if NORMALIZED_PACKAGE.fullmatch(normalized) is None:
+        raise ContextError("wheel has invalid package name")
+    return normalized
+
+
+def _regular_files(root: Path, *, suffix: str, maximum: int) -> list[Path]:
+    if root.is_symlink() or not root.is_dir():
+        raise ContextError(f"input directory is not a real directory: {root}")
+    values = sorted(path for path in root.iterdir() if path.name.endswith(suffix))
+    if len(values) > maximum:
+        raise ContextError(f"input directory exceeds {maximum} files")
+    for path in values:
+        if path.is_symlink() or not path.is_file():
+            raise ContextError(f"input artifact is not a regular file: {path.name}")
+    return values
+
+
+def _copy_web_tree(
+    source: Path,
+    target: Path,
+    *,
+    source_date_epoch: int,
+) -> list[dict[str, object]]:
+    if source.is_symlink() or not source.is_dir():
+        raise ContextError("WebUI dist must be a real directory")
+    rows: list[dict[str, object]] = []
+    total = 0
+    for path in sorted(source.rglob("*")):
+        relative = path.relative_to(source)
+        if path.is_symlink():
+            raise ContextError(f"WebUI dist contains a symlink: {relative}")
+        if path.is_dir():
+            continue
+        if not path.is_file():
+            raise ContextError(f"WebUI dist contains a special file: {relative}")
+        if len(rows) >= MAX_WEB_FILES:
+            raise ContextError("WebUI dist exceeds its file-count limit")
+        total += path.stat().st_size
+        if total > MAX_WEB_BYTES:
+            raise ContextError("WebUI dist exceeds its total-size limit")
+        destination = target / relative
+        _copy_regular(path, destination, source_date_epoch=source_date_epoch)
+        rows.append(
+            {
+                "path": relative.as_posix(),
+                "sha256": _sha256_file(destination),
+                "size": destination.stat().st_size,
+            }
+        )
+    if not rows:
+        raise ContextError("WebUI dist contains no files")
+    return rows
+
+
+def _copy_regular(source: Path, target: Path, *, source_date_epoch: int) -> None:
+    target.parent.mkdir(mode=0o755, parents=True, exist_ok=True)
+    with source.open("rb") as source_handle, target.open("xb") as target_handle:
+        shutil.copyfileobj(source_handle, target_handle)
+        target_handle.flush()
+        os.fsync(target_handle.fileno())
+    target.chmod(0o644)
+    os.utime(target, (source_date_epoch, source_date_epoch))
+
+
+def _write_regular(path: Path, value: bytes, *, source_date_epoch: int) -> None:
+    path.parent.mkdir(mode=0o755, parents=True, exist_ok=True)
+    path.write_bytes(value)
+    path.chmod(0o644)
+    os.utime(path, (source_date_epoch, source_date_epoch))
+
+
+def _sha256_file(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as handle:
+        for chunk in iter(lambda: handle.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def _rows_digest(rows: list[dict[str, object]]) -> str:
+    encoded = json.dumps(rows, separators=(",", ":"), sort_keys=True).encode(
+        "utf-8"
+    )
+    return hashlib.sha256(encoded).hexdigest()
+
+
+def main() -> int:
+    args = build_parser().parse_args()
+    try:
+        composition = prepare_context(
+            wheelhouse=args.wheelhouse.expanduser().resolve(),
+            web_dist=args.web_dist.expanduser().resolve(),
+            output=args.output.expanduser().resolve(),
+            required_modules=tuple(args.required_module),
+            source_date_epoch=args.source_date_epoch,
+        )
+    except (ContextError, OSError) as exc:
+        print(f"error: {exc}", file=os.sys.stderr)
+        return 1
+    print(json.dumps(composition, indent=2, sort_keys=True))
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/tools/release/publish-runtime-release.py b/tools/release/publish-runtime-release.py
new file mode 100644
index 0000000..1ea099a
--- /dev/null
+++ b/tools/release/publish-runtime-release.py
@@ -0,0 +1,202 @@
+#!/usr/bin/env python3
+"""Publish immutable GovOPlaN runtime evidence as Gitea release assets."""
+
+from __future__ import annotations
+
+import argparse
+import hashlib
+import json
+import mimetypes
+import os
+from pathlib import Path
+import secrets
+import sys
+from typing import Any
+from urllib.error import HTTPError
+from urllib.parse import quote, urlencode
+from urllib.request import Request, urlopen
+
+
+MAX_ASSET_BYTES = 256 * 1024 * 1024
+
+
+class PublishError(RuntimeError):
+    """A release asset cannot be published immutably."""
+
+
+def build_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--base-url", default="https://git.add-ideas.de")
+    parser.add_argument("--owner", default="GovOPlaN")
+    parser.add_argument("--repo", default="govoplan")
+    parser.add_argument("--tag", required=True)
+    parser.add_argument("--title", required=True)
+    parser.add_argument("--body", default="Signed GovOPlaN runtime distribution.")
+    parser.add_argument("--asset", type=Path, action="append", default=[], required=True)
+    parser.add_argument("--token-env", default="GITEA_RELEASE_TOKEN")
+    return parser
+
+
+class GiteaReleasePublisher:
+    def __init__(self, *, base_url: str, owner: str, repo: str, token: str) -> None:
+        if not base_url.startswith("https://"):
+            raise PublishError("Gitea release publication requires HTTPS")
+        if not token:
+            raise PublishError("Gitea release token is empty")
+        self.base_url = base_url.rstrip("/")
+        self.owner = owner
+        self.repo = repo
+        self.token = token
+
+    def release(self, *, tag: str, title: str, body: str) -> dict[str, Any]:
+        path = self._repo_path(f"/releases/tags/{quote(tag, safe='')}")
+        try:
+            return self._json("GET", path)
+        except HTTPError as exc:
+            if exc.code != 404:
+                raise
+        return self._json(
+            "POST",
+            self._repo_path("/releases"),
+            payload={
+                "tag_name": tag,
+                "name": title,
+                "body": body,
+                "draft": False,
+                "prerelease": False,
+            },
+            expected=201,
+        )
+
+    def upload_assets(self, release: dict[str, Any], assets: tuple[Path, ...]) -> None:
+        release_id = release.get("id")
+        if isinstance(release_id, bool) or not isinstance(release_id, int):
+            raise PublishError("Gitea release response has no numeric id")
+        existing = self._json(
+            "GET",
+            self._repo_path(f"/releases/{release_id}/assets"),
+        )
+        if not isinstance(existing, list):
+            raise PublishError("Gitea release assets response is invalid")
+        existing_by_name = {
+            str(item.get("name")): item for item in existing if isinstance(item, dict)
+        }
+        for asset in assets:
+            path = asset.expanduser().resolve()
+            if path.is_symlink() or not path.is_file():
+                raise PublishError(f"release asset is not a regular file: {path}")
+            size = path.stat().st_size
+            if size > MAX_ASSET_BYTES:
+                raise PublishError(f"release asset exceeds size limit: {path.name}")
+            prior = existing_by_name.get(path.name)
+            if prior is not None:
+                self._require_same_existing_asset(prior, path)
+                continue
+            self._upload(release_id, path)
+
+    def _require_same_existing_asset(self, prior: dict[str, Any], path: Path) -> None:
+        url = prior.get("browser_download_url")
+        size = prior.get("size")
+        if not isinstance(url, str) or not url.startswith("https://") or size != path.stat().st_size:
+            raise PublishError(f"release asset already exists with another identity: {path.name}")
+        request = Request(url, headers=self._headers())
+        digest = hashlib.sha256()
+        total = 0
+        with urlopen(request, timeout=30) as response:  # noqa: S310
+            while True:
+                chunk = response.read(1024 * 1024)
+                if not chunk:
+                    break
+                total += len(chunk)
+                if total > MAX_ASSET_BYTES:
+                    raise PublishError("existing release asset exceeds size limit")
+                digest.update(chunk)
+        if digest.hexdigest() != _sha256_file(path):
+            raise PublishError(f"release asset already exists with another digest: {path.name}")
+
+    def _upload(self, release_id: int, path: Path) -> None:
+        boundary = "govoplan-" + secrets.token_hex(16)
+        content_type = mimetypes.guess_type(path.name)[0] or "application/octet-stream"
+        prefix = (
+            f"--{boundary}\r\n"
+            f'Content-Disposition: form-data; name="attachment"; filename="{path.name}"\r\n'
+            f"Content-Type: {content_type}\r\n\r\n"
+        ).encode("utf-8")
+        suffix = f"\r\n--{boundary}--\r\n".encode("ascii")
+        data = prefix + path.read_bytes() + suffix
+        query = urlencode({"name": path.name})
+        request = Request(
+            self._repo_path(f"/releases/{release_id}/assets") + "?" + query,
+            data=data,
+            method="POST",
+            headers={
+                **self._headers(),
+                "Content-Type": f"multipart/form-data; boundary={boundary}",
+            },
+        )
+        try:
+            with urlopen(request, timeout=120) as response:  # noqa: S310
+                if response.status != 201:
+                    raise PublishError(
+                        f"Gitea asset upload returned HTTP {response.status}"
+                    )
+        except HTTPError as exc:
+            raise PublishError(f"Gitea asset upload failed with HTTP {exc.code}") from exc
+
+    def _json(
+        self,
+        method: str,
+        url: str,
+        *,
+        payload: dict[str, Any] | None = None,
+        expected: int = 200,
+    ) -> Any:
+        data = None
+        headers = self._headers()
+        if payload is not None:
+            data = json.dumps(payload).encode("utf-8")
+            headers["Content-Type"] = "application/json"
+        request = Request(url, data=data, method=method, headers=headers)
+        with urlopen(request, timeout=30) as response:  # noqa: S310
+            if response.status != expected:
+                raise PublishError(f"Gitea API returned HTTP {response.status}")
+            return json.load(response)
+
+    def _headers(self) -> dict[str, str]:
+        return {"Authorization": f"token {self.token}", "Accept": "application/json"}
+
+    def _repo_path(self, suffix: str) -> str:
+        return (
+            f"{self.base_url}/api/v1/repos/{quote(self.owner, safe='')}/"
+            f"{quote(self.repo, safe='')}{suffix}"
+        )
+
+
+def _sha256_file(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as handle:
+        for chunk in iter(lambda: handle.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def main() -> int:
+    args = build_parser().parse_args()
+    try:
+        publisher = GiteaReleasePublisher(
+            base_url=args.base_url,
+            owner=args.owner,
+            repo=args.repo,
+            token=os.environ.get(args.token_env, ""),
+        )
+        release = publisher.release(tag=args.tag, title=args.title, body=args.body)
+        publisher.upload_assets(release, tuple(args.asset))
+    except (HTTPError, OSError, PublishError, ValueError) as exc:
+        print(f"error: {exc}", file=sys.stderr)
+        return 1
+    print(f"Published {len(args.asset)} immutable asset(s) to {args.owner}/{args.repo} {args.tag}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/tools/release/resolve-oci-platforms.py b/tools/release/resolve-oci-platforms.py
new file mode 100644
index 0000000..635d9cb
--- /dev/null
+++ b/tools/release/resolve-oci-platforms.py
@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+"""Resolve amd64/arm64 child digests from an OCI image index."""
+
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+import re
+import sys
+
+
+DIGEST = re.compile(r"^sha256:[0-9a-f]{64}$")
+
+
+def resolve_platforms(
+    payload: object,
+    *,
+    repository: str,
+    index_digest: str,
+) -> dict[str, object]:
+    if not repository or "@" in repository or any(value.isspace() for value in repository):
+        raise ValueError("repository must be an unpinned OCI repository name")
+    if DIGEST.fullmatch(index_digest) is None:
+        raise ValueError("index digest must be sha256:<hex>")
+    if not isinstance(payload, dict) or not isinstance(payload.get("manifests"), list):
+        raise ValueError("OCI index must contain manifests")
+    platforms: dict[str, str] = {}
+    for item in payload["manifests"]:
+        if not isinstance(item, dict) or not isinstance(item.get("platform"), dict):
+            continue
+        platform = item["platform"]
+        key = f"{platform.get('os')}/{platform.get('architecture')}"
+        if key not in {"linux/amd64", "linux/arm64"}:
+            continue
+        digest = item.get("digest")
+        if not isinstance(digest, str) or DIGEST.fullmatch(digest) is None:
+            raise ValueError(f"OCI index has an invalid {key} digest")
+        if key in platforms:
+            raise ValueError(f"OCI index has duplicate {key} manifests")
+        platforms[key] = f"{repository}@{digest}"
+    if set(platforms) != {"linux/amd64", "linux/arm64"}:
+        raise ValueError("OCI index must contain linux/amd64 and linux/arm64")
+    return {
+        "index": f"{repository}@{index_digest}",
+        "platforms": dict(sorted(platforms.items())),
+    }
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--repository", required=True)
+    parser.add_argument("--index-digest", required=True)
+    parser.add_argument("--index", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    args = parser.parse_args()
+    try:
+        payload = json.loads(args.index.read_text(encoding="utf-8"))
+        result = resolve_platforms(
+            payload,
+            repository=args.repository,
+            index_digest=args.index_digest,
+        )
+        args.output.parent.mkdir(parents=True, exist_ok=True)
+        args.output.write_text(
+            json.dumps(result, indent=2, sort_keys=True) + "\n",
+            encoding="utf-8",
+        )
+    except (OSError, ValueError, json.JSONDecodeError) as exc:
+        print(f"error: {exc}", file=sys.stderr)
+        return 1
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/tools/release/runtime/Dockerfile.api b/tools/release/runtime/Dockerfile.api
new file mode 100644
index 0000000..81453ab
--- /dev/null
+++ b/tools/release/runtime/Dockerfile.api
@@ -0,0 +1,36 @@
+# syntax=docker/dockerfile:1.7
+ARG PYTHON_IMAGE
+FROM ${PYTHON_IMAGE}
+
+ARG GOVOPLAN_RELEASE_VERSION
+ARG GOVOPLAN_COMPOSITION_SHA256
+LABEL org.opencontainers.image.title="GovOPlaN API runtime" \
+      org.opencontainers.image.version="${GOVOPLAN_RELEASE_VERSION}" \
+      org.govoplan.composition.sha256="${GOVOPLAN_COMPOSITION_SHA256}"
+
+ENV PYTHONUNBUFFERED=1 \
+    PYTHONDONTWRITEBYTECODE=1 \
+    PYTHONPATH=/opt/govoplan/runtime \
+    PATH=/opt/govoplan/runtime/bin:${PATH} \
+    HOME=/var/lib/govoplan
+
+COPY wheelhouse/ /opt/govoplan/wheels/
+COPY requirements-runtime.txt composition.json /opt/govoplan/
+RUN python -m pip install --disable-pip-version-check --no-cache-dir \
+      --no-index --find-links=/opt/govoplan/wheels \
+      --target=/opt/govoplan/runtime \
+      --requirement=/opt/govoplan/requirements-runtime.txt \
+    && rm -rf /opt/govoplan/wheels \
+    && groupadd --gid 10001 govoplan \
+    && useradd --uid 10001 --gid 10001 --home-dir /var/lib/govoplan \
+      --create-home --shell /usr/sbin/nologin govoplan \
+    && mkdir -p /var/lib/govoplan /tmp/govoplan \
+    && chown -R 10001:10001 /var/lib/govoplan /tmp/govoplan \
+    && chmod -R a-w /opt/govoplan
+
+USER 10001:10001
+WORKDIR /var/lib/govoplan
+EXPOSE 8000
+HEALTHCHECK --interval=10s --timeout=5s --start-period=20s --retries=12 \
+  CMD ["python", "-c", "import urllib.request; urllib.request.urlopen('http://127.0.0.1:8000/health/ready', timeout=3)"]
+CMD ["python", "-m", "uvicorn", "govoplan_core.server.app:app", "--host", "0.0.0.0", "--port", "8000", "--proxy-headers"]
diff --git a/tools/release/runtime/Dockerfile.web b/tools/release/runtime/Dockerfile.web
new file mode 100644
index 0000000..f41cf51
--- /dev/null
+++ b/tools/release/runtime/Dockerfile.web
@@ -0,0 +1,21 @@
+# syntax=docker/dockerfile:1.7
+ARG NGINX_IMAGE
+FROM ${NGINX_IMAGE}
+
+ARG GOVOPLAN_RELEASE_VERSION
+ARG GOVOPLAN_COMPOSITION_SHA256
+LABEL org.opencontainers.image.title="GovOPlaN WebUI runtime" \
+      org.opencontainers.image.version="${GOVOPLAN_RELEASE_VERSION}" \
+      org.govoplan.composition.sha256="${GOVOPLAN_COMPOSITION_SHA256}"
+
+USER 0
+RUN rm -rf /usr/share/nginx/html/* /etc/nginx/conf.d/*
+COPY web-dist/ /usr/share/nginx/html/
+COPY nginx.conf /etc/nginx/nginx.conf
+RUN chown -R 101:101 /usr/share/nginx/html \
+    && chmod -R a-w /usr/share/nginx/html /etc/nginx/nginx.conf
+
+USER 101:101
+EXPOSE 8080
+ENTRYPOINT []
+CMD ["nginx", "-g", "daemon off;"]
diff --git a/tools/release/runtime/nginx.conf b/tools/release/runtime/nginx.conf
new file mode 100644
index 0000000..e0821fc
--- /dev/null
+++ b/tools/release/runtime/nginx.conf
@@ -0,0 +1,41 @@
+pid /tmp/nginx.pid;
+worker_processes auto;
+
+events {
+    worker_connections 1024;
+}
+
+http {
+    include /etc/nginx/mime.types;
+    default_type application/octet-stream;
+    access_log /dev/stdout;
+    error_log /dev/stderr warn;
+    sendfile on;
+    server_tokens off;
+    client_body_temp_path /tmp/client_temp;
+    proxy_temp_path /tmp/proxy_temp;
+
+    server {
+        listen 8080;
+        root /usr/share/nginx/html;
+
+        location = /health {
+            access_log off;
+            default_type text/plain;
+            return 200 "ok\n";
+        }
+
+        location /api/ {
+            proxy_pass http://load-balancer:8000;
+            proxy_http_version 1.1;
+            proxy_set_header Host $host;
+            proxy_set_header X-Forwarded-Host $host;
+            proxy_set_header X-Forwarded-Proto $scheme;
+            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        }
+
+        location / {
+            try_files $uri $uri/ /index.html;
+        }
+    }
+}