diff --git a/install.sh b/install.sh
index a6bb943..8559fd0 100755
--- a/install.sh
+++ b/install.sh
@@ -226,6 +226,10 @@ download_one() {
   local relative=$1 url=$2 expected=$3 target="$MODEL_DIR/$1"
   install -d -m 0755 "$(dirname "$target")"
   if [[ -f $target ]] && printf '%s  %s\n' "$expected" "$target" | sha256sum -c - >/dev/null 2>&1; then
+    # The installer itself runs with umask 077, but inference runs deliberately
+    # unprivileged. Models are immutable inputs: globally readable, never
+    # writable by the runtime container.
+    chmod 0444 "$target"
     printf 'Vorhanden und geprüft: %s\n' "$relative"
     return
   fi
@@ -234,6 +238,7 @@ download_one() {
     --output "$target.partial" "$url"
   printf '%s  %s\n' "$expected" "$target.partial" | sha256sum -c -
   mv "$target.partial" "$target"
+  chmod 0444 "$target"
 }
 
 download_models() {
@@ -333,7 +338,8 @@ build_and_start() {
   # Use docker exec directly here. Some Compose/Docker combinations return a
   # transient HTTP 409 while upgrading the exec stream immediately after a
   # freshly built service has been recreated.
-  docker exec -i mike-ai-router python - <<'PY'
+  local activation_output
+  activation_output=$(docker exec -i mike-ai-router python - <<'PY'
 import json, os, time, urllib.request
 key = os.environ["ROUTER_API_KEY"]
 request = urllib.request.Request(
@@ -347,6 +353,7 @@ while time.monotonic() < deadline:
         with urllib.request.urlopen("http://127.0.0.1:8081/ready", timeout=5) as response:
             if response.status == 200:
                 print("Router und Fast-Profil sind bereit.")
+                print("INSTALL_READINESS_OK")
                 break
     except Exception:
         pass
@@ -354,6 +361,10 @@ while time.monotonic() < deadline:
 else:
     raise SystemExit("Readiness-Check fehlgeschlagen")
 PY
+  ) || die "Fast-Profil konnte nicht aktiviert werden"
+  printf '%s\n' "$activation_output"
+  grep -Fxq 'INSTALL_READINESS_OK' <<<"$activation_output" || \
+    die "Fast-Profil lieferte keinen bestätigten Readiness-Marker"
 }
 
 hostnamectl set-hostname "$AI_HOSTNAME"