diff --git a/backend/db.py b/backend/db.py
index b698e5d..9daf7c1 100644
--- a/backend/db.py
+++ b/backend/db.py
@@ -3,6 +3,16 @@ from pathlib import Path
 
 BASE_DIR = Path(__file__).resolve().parent.parent
 DB_PATH = BASE_DIR / "data" / "staysense.db"
+REQUIRED_TABLES = {
+    "spot",
+    "community_signal",
+    "osm_poi",
+    "osm_zone",
+    "osm_road",
+    "open_data_event",
+    "data_source_state",
+    "admin_user",
+}
 
 
 def get_conn() -> sqlite3.Connection:
@@ -21,8 +31,7 @@ def init_db() -> None:
         except sqlite3.OperationalError:
             # Some deployments run with read-only db mounts; continue without WAL.
             pass
-        conn.executescript(
-            """
+        schema_sql = """
             CREATE TABLE IF NOT EXISTS spot (
                 id TEXT PRIMARY KEY,
                 lat REAL NOT NULL,
@@ -134,4 +143,14 @@ def init_db() -> None:
             CREATE INDEX IF NOT EXISTS idx_open_data_event_source
               ON open_data_event (source);
             """
-        )
+        try:
+            conn.executescript(schema_sql)
+        except sqlite3.OperationalError as exc:
+            if "readonly" not in str(exc).lower():
+                raise
+            # In read-only mode, continue if schema is already present.
+            rows = conn.execute("SELECT name FROM sqlite_master WHERE type='table'").fetchall()
+            existing = {str(row["name"]) for row in rows}
+            missing = REQUIRED_TABLES - existing
+            if missing:
+                raise
diff --git a/deploy/scripts/staysense-watchdog.sh b/deploy/scripts/staysense-watchdog.sh
new file mode 100755
index 0000000..157e5d1
--- /dev/null
+++ b/deploy/scripts/staysense-watchdog.sh
@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+HEALTH_URL="${HEALTH_URL:-http://127.0.0.1:8787/health}"
+TIMEOUT_SECONDS="${TIMEOUT_SECONDS:-5}"
+
+if ! curl -fsS --max-time "${TIMEOUT_SECONDS}" "${HEALTH_URL}" >/dev/null; then
+  logger -t staysense-watchdog "healthcheck failed for ${HEALTH_URL}, restarting staysense-api.service"
+  systemctl restart staysense-api.service
+fi
diff --git a/deploy/systemd/staysense-api.service b/deploy/systemd/staysense-api.service
index b31df62..e3481b1 100644
--- a/deploy/systemd/staysense-api.service
+++ b/deploy/systemd/staysense-api.service
@@ -5,11 +5,15 @@ Wants=network-online.target
 
 [Service]
 Type=simple
-User=www-data
-Group=www-data
+User=staysense
+Group=staysense
 WorkingDirectory=/opt/staysense/backend
 Environment=STAYSENSE_SERVER_SALT=CHANGE_ME
 Environment=STAYSENSE_SIGNAL_COOLDOWN_HOURS=24
+UMask=0002
+PermissionsStartOnly=true
+ExecStartPre=/usr/bin/install -d -o staysense -g staysense -m 2775 /opt/staysense/data
+ExecStartPre=/bin/sh -c '/usr/bin/chown -f staysense:staysense /opt/staysense/data/staysense.db /opt/staysense/data/staysense.db-wal /opt/staysense/data/staysense.db-shm || true'
 ExecStart=/usr/bin/python3 /opt/staysense/backend/server.py
 Restart=always
 RestartSec=3
diff --git a/deploy/systemd/staysense-import.service b/deploy/systemd/staysense-import.service
index 38b964c..715af8b 100644
--- a/deploy/systemd/staysense-import.service
+++ b/deploy/systemd/staysense-import.service
@@ -5,7 +5,8 @@ Wants=network-online.target
 
 [Service]
 Type=oneshot
-User=www-data
-Group=www-data
+User=staysense
+Group=staysense
 WorkingDirectory=/opt/staysense/backend
+UMask=0002
 ExecStart=/usr/bin/python3 /opt/staysense/backend/run_import_jobs.py --config /opt/staysense/docs/open_data_sources_nrw_live.json --prune-legacy
diff --git a/deploy/systemd/staysense-watchdog.service b/deploy/systemd/staysense-watchdog.service
new file mode 100644
index 0000000..0392a3a
--- /dev/null
+++ b/deploy/systemd/staysense-watchdog.service
@@ -0,0 +1,8 @@
+[Unit]
+Description=StaySense API Health Watchdog
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=oneshot
+ExecStart=/usr/bin/env bash /opt/staysense/deploy/scripts/staysense-watchdog.sh
diff --git a/deploy/systemd/staysense-watchdog.timer b/deploy/systemd/staysense-watchdog.timer
new file mode 100644
index 0000000..8ccbce7
--- /dev/null
+++ b/deploy/systemd/staysense-watchdog.timer
@@ -0,0 +1,10 @@
+[Unit]
+Description=Run StaySense API Watchdog every minute
+
+[Timer]
+OnBootSec=90s
+OnUnitActiveSec=60s
+Unit=staysense-watchdog.service
+
+[Install]
+WantedBy=timers.target
diff --git a/docs/DEPLOYMENT.md b/docs/DEPLOYMENT.md
index 454afae..b24e8f5 100644
--- a/docs/DEPLOYMENT.md
+++ b/docs/DEPLOYMENT.md
@@ -13,6 +13,7 @@ Install:
 ```bash
 sudo apt update
 sudo apt install -y python3 nginx
+sudo useradd --system --create-home --shell /usr/sbin/nologin staysense || true
 ```
 
 ## 2. Code bereitstellen
@@ -21,6 +22,9 @@ sudo apt install -y python3 nginx
 sudo mkdir -p /opt/staysense
 sudo chown -R $USER:$USER /opt/staysense
 git clone <REPO_URL> /opt/staysense
+sudo mkdir -p /opt/staysense/data
+sudo chown -R staysense:staysense /opt/staysense/data
+sudo chmod 2775 /opt/staysense/data
 ```
 
 ## 3. Initialisierung
@@ -60,8 +64,11 @@ sudo systemctl status staysense-api.service
 ```bash
 sudo cp /opt/staysense/deploy/systemd/staysense-import.service /etc/systemd/system/
 sudo cp /opt/staysense/deploy/systemd/staysense-import.timer /etc/systemd/system/
+sudo cp /opt/staysense/deploy/systemd/staysense-watchdog.service /etc/systemd/system/
+sudo cp /opt/staysense/deploy/systemd/staysense-watchdog.timer /etc/systemd/system/
 sudo systemctl daemon-reload
 sudo systemctl enable --now staysense-import.timer
+sudo systemctl enable --now staysense-watchdog.timer
 sudo systemctl list-timers | grep staysense
 ```
 
@@ -99,4 +106,5 @@ sudo certbot --nginx -d staysense.example.com
 curl -s http://127.0.0.1:8787/health
 sudo journalctl -u staysense-api.service -f
 sudo journalctl -u staysense-import.service -n 100
+sudo journalctl -u staysense-watchdog.service -n 50
 ```
diff --git a/docs/OPERATIONS.md b/docs/OPERATIONS.md
index 2e55583..0ab6d01 100644
--- a/docs/OPERATIONS.md
+++ b/docs/OPERATIONS.md
@@ -34,6 +34,21 @@ Health check:
 curl -s http://127.0.0.1:8787/health
 ```
 
+Watchdog pruefen:
+
+```bash
+sudo systemctl status staysense-watchdog.timer --no-pager
+sudo journalctl -u staysense-watchdog.service -n 80 --no-pager
+```
+
+## DB Read-Only Sofortfix
+
+```bash
+sudo chown -R staysense:staysense /opt/staysense/data
+sudo chmod 2775 /opt/staysense/data
+sudo systemctl restart staysense-api.service
+```
+
 ## Backup
 
 ```bash
diff --git a/docs/wiki/Deployment.md b/docs/wiki/Deployment.md
index 9bc9666..38c654c 100644
--- a/docs/wiki/Deployment.md
+++ b/docs/wiki/Deployment.md
@@ -7,6 +7,7 @@ Zielplattform aktuell: Hetzner + CloudPanel + Nginx + systemd.
 - App-Code: `/opt/staysense`
 - API-Service: `staysense-api.service`
 - Import-Timer: `staysense-import.timer`
+- API-Watchdog: `staysense-watchdog.timer`
 - Frontend-Root: `/home/staysense-site/htdocs/staysense.vanityontour.de/`
 
 ## Rollout (vereinfacht)
@@ -17,12 +18,14 @@ git pull --ff-only
 rsync -a --delete /opt/staysense/src/ /home/staysense-site/htdocs/staysense.vanityontour.de/
 systemctl restart staysense-api.service
 nginx -t && systemctl reload nginx
+systemctl restart staysense-watchdog.timer
 ```
 
 ## Pflichtchecks
 
 ```bash
 systemctl is-active staysense-api.service
+systemctl is-active staysense-watchdog.timer
 curl -s -L https://staysense.vanityontour.de/api/health
 ```
 
diff --git a/docs/wiki/Operations-Runbook.md b/docs/wiki/Operations-Runbook.md
index b40cc73..ce8ca41 100644
--- a/docs/wiki/Operations-Runbook.md
+++ b/docs/wiki/Operations-Runbook.md
@@ -5,6 +5,7 @@
 ```bash
 systemctl status staysense-api.service --no-pager
 systemctl status staysense-import.timer --no-pager
+systemctl status staysense-watchdog.timer --no-pager
 curl -s https://staysense.vanityontour.de/api/health
 ```
 
@@ -13,6 +14,7 @@ curl -s https://staysense.vanityontour.de/api/health
 ```bash
 journalctl -u staysense-api.service --no-pager -n 120
 journalctl -u staysense-import.service --no-pager -n 120
+journalctl -u staysense-watchdog.service --no-pager -n 120
 ```
 
 ## Häufige Fehlerbilder
@@ -25,6 +27,12 @@ journalctl -u staysense-import.service --no-pager -n 120
 - Datenverzeichnisrechte prüfen
 - Service-User und Besitzrechte prüfen
 
+```bash
+chown -R staysense:staysense /opt/staysense/data
+chmod 2775 /opt/staysense/data
+systemctl restart staysense-api.service
+```
+
 3. Importdaten veraltet
 - Timer-Status prüfen
 - Import-Service manuell starten