diff --git a/Dockerfile b/Dockerfile
index c4bc75b..3b2787a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -14,7 +14,7 @@ COPY .forgejo/workflows/image.yaml ./.forgejo/workflows/image.yaml
 COPY schemas/ ./schemas/
 COPY k8s/ ./k8s/
 COPY scripts/render_gitops.py scripts/check_gitops_promotion.py ./scripts/
-RUN uv sync --frozen --extra dev && uv run --no-sync pytest -q -p no:cacheprovider tests/test_frontend_patterns.py tests/test_instruction_evaluation.py tests/test_admin_sync_api.py tests/test_gitops_release.py
+RUN uv sync --frozen --extra dev && uv run --no-sync python scripts/render_gitops.py --check --verify-frontend && uv run --no-sync pytest -q -p no:cacheprovider tests/test_frontend_patterns.py tests/test_instruction_evaluation.py tests/test_admin_sync_api.py tests/test_gitops_release.py
 
 # Stage 2 — runtime image
 FROM python:3.12-slim@sha256:78387bc3881b8273120a12ebe6c1ab22b018ccc2c9adf565ae1ac9b536e184ea AS runtime
diff --git a/k8s/gitops/frontend-source.json b/k8s/gitops/frontend-source.json
new file mode 100644
index 0000000..d789616
--- /dev/null
+++ b/k8s/gitops/frontend-source.json
@@ -0,0 +1,10 @@
+{
+  "schema_version": 1,
+  "repository": "coulomb/frontend-patterns",
+  "revision": "10f0131f67daac14b14d48735f71db65366ebde5",
+  "files": {
+    "frontend-patterns-daily.md": "b604873587003c96a7015d705936a5aaf865123e34b4be3afe928c459a02c7d1",
+    "frontend-patterns-monthly.md": "52755a99c02e6ed4ef1f99261bbb5ce59214b6761b360aa467b405e4932c9b98",
+    "frontend-patterns-weekly.md": "5437dc5fbcec8fecbbca0e0c53531750c90a9aa5c044df5b1b40e4b96af9c186"
+  }
+}
diff --git a/scripts/render_gitops.py b/scripts/render_gitops.py
index 5caa793..9a312bd 100644
--- a/scripts/render_gitops.py
+++ b/scripts/render_gitops.py
@@ -1,5 +1,9 @@
 """Render only the reviewed application resource set, excluding jobs and custody."""
 import argparse
+import hashlib
+import json
+import re
+import urllib.request
 from pathlib import Path
 import yaml
 ROOT=Path(__file__).resolve().parents[1]
@@ -22,9 +26,25 @@ def render():
    if d['metadata'].get('namespace')!='activity-core': raise ValueError('namespace outside grant')
    selected.append(d)
  return '# Generated by scripts/render_gitops.py; do not edit directly.\n'+'---\n'.join(yaml.dump(d,Dumper=Dumper,sort_keys=False) for d in selected)
+def verify_frontend(source_dir=None):
+ pin=json.loads((ROOT/'k8s/gitops/frontend-source.json').read_text())
+ names={f'frontend-patterns-{mode}.md' for mode in ('daily','weekly','monthly')}
+ if pin.get('schema_version')!=1 or pin.get('repository')!='coulomb/frontend-patterns' or set(pin['files'])!=names or not re.fullmatch('[0-9a-f]{40}',pin['revision']):
+  raise ValueError('invalid frontend source pin')
+ cm=next(d for d in yaml.safe_load_all(render()) if d['metadata']['name']=='actcore-external-activity-definitions')
+ for name,digest in pin['files'].items():
+  if source_dir is None:
+   url=f"https://forgejo.coulomb.social/coulomb/frontend-patterns/raw/commit/{pin['revision']}/activity-definitions/{name}"
+   with urllib.request.urlopen(url,timeout=10) as response: body=response.read(32769)
+  else: body=(Path(source_dir)/name).read_bytes()
+  if len(body)>32768 or hashlib.sha256(body).hexdigest()!=digest or cm['data'][name].encode()!=body:
+   raise ValueError('frontend definition projection mismatch: '+name)
+
 if __name__=='__main__':
- parser=argparse.ArgumentParser(); parser.add_argument('--check',action='store_true'); args=parser.parse_args()
+ parser=argparse.ArgumentParser(); parser.add_argument('--check',action='store_true'); parser.add_argument('--verify-frontend',action='store_true'); args=parser.parse_args()
  path=ROOT/'k8s/gitops/runtime.yaml'; text=render()
  if args.check:
   if path.read_text()!=text: raise SystemExit('GitOps projection stale; run scripts/render_gitops.py')
  else: path.write_text(text)
+
+ if args.verify_frontend: verify_frontend()
diff --git a/tests/test_gitops_release.py b/tests/test_gitops_release.py
index 6c74ecb..c6ce51e 100644
--- a/tests/test_gitops_release.py
+++ b/tests/test_gitops_release.py
@@ -62,3 +62,13 @@ def test_refuses_authority_expansion(change):
  elif change=='tag':c['image']='forgejo.coulomb.social/coulomb/activity-core:latest'
  else:after.pop()
  with pytest.raises(ValueError):load('check_gitops_promotion').validate(before,after,evidence,now)
+
+
+def test_frontend_projection_checks_content_and_pin(tmp_path):
+ renderer=load('render_gitops')
+ cm=next(d for d in yaml.safe_load_all(renderer.render()) if d['metadata']['name']=='actcore-external-activity-definitions')
+ for name,body in cm['data'].items():
+  if name.startswith('frontend-patterns-'): (tmp_path/name).write_text(body)
+ renderer.verify_frontend(tmp_path)
+ (tmp_path/'frontend-patterns-daily.md').write_text('tampered')
+ with pytest.raises(ValueError): renderer.verify_frontend(tmp_path)