diff --git a/.env.example b/.env.example
index d58eee8..0b0e063 100644
--- a/.env.example
+++ b/.env.example
@@ -1,5 +1,15 @@
 # L1 Server Configuration
 
+# PostgreSQL password (REQUIRED - no default)
+POSTGRES_PASSWORD=changeme-generate-with-openssl-rand-hex-16
+
+# Admin token for purge operations (REQUIRED - no default)
+# Generate with: openssl rand -hex 32
+ADMIN_TOKEN=changeme-generate-with-openssl-rand-hex-32
+
+# L1 host IP/hostname for GPU worker cross-VPC access
+L1_HOST=your-l1-server-ip
+
 # This L1 server's public URL (sent to L2 when publishing)
 L1_PUBLIC_URL=https://l1.artdag.rose-ash.com
 
diff --git a/README.md b/README.md
index c6ab6f6..d387437 100644
--- a/README.md
+++ b/README.md
@@ -60,7 +60,7 @@ The stack includes:
 | `HOST` | `0.0.0.0` | Server bind address |
 | `PORT` | `8000` | Server port |
 | `REDIS_URL` | `redis://localhost:6379/5` | Redis connection |
-| `DATABASE_URL` | `postgresql://artdag:artdag@localhost:5432/artdag` | PostgreSQL connection |
+| `DATABASE_URL` | **(required)** | PostgreSQL connection |
 | `CACHE_DIR` | `~/.artdag/cache` | Local cache directory |
 | `IPFS_API` | `/dns/localhost/tcp/5001` | IPFS API multiaddr |
 | `IPFS_GATEWAY_URL` | `https://ipfs.io/ipfs` | Public IPFS gateway |
diff --git a/app/config.py b/app/config.py
index 90f7540..bec2032 100644
--- a/app/config.py
+++ b/app/config.py
@@ -33,9 +33,7 @@ class Settings:
 
     # Database
     database_url: str = field(
-        default_factory=lambda: os.environ.get(
-            "DATABASE_URL", "postgresql://artdag:artdag@localhost:5432/artdag"
-        )
+        default_factory=lambda: os.environ.get("DATABASE_URL", "")
     )
 
     # IPFS
diff --git a/database.py b/database.py
index 4e58f42..70187db 100644
--- a/database.py
+++ b/database.py
@@ -11,7 +11,9 @@ from typing import List, Optional
 
 import asyncpg
 
-DATABASE_URL = os.getenv("DATABASE_URL", "postgresql://artdag:artdag@localhost:5432/artdag")
+DATABASE_URL = os.getenv("DATABASE_URL")
+if not DATABASE_URL:
+    raise RuntimeError("DATABASE_URL environment variable is required")
 
 pool: Optional[asyncpg.Pool] = None
 
diff --git a/docker-compose.yml b/docker-compose.yml
index e791323..a6a64b9 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -23,7 +23,7 @@ services:
     image: postgres:16-alpine
     environment:
       - POSTGRES_USER=artdag
-      - POSTGRES_PASSWORD=artdag
+      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
       - POSTGRES_DB=artdag
     ports:
       - target: 5432
@@ -69,8 +69,8 @@ services:
       - .env
     environment:
       - REDIS_URL=redis://redis:6379/5
-      - DATABASE_URL=postgresql://artdag:artdag@postgres:5432/artdag
-      - ADMIN_TOKEN=artdag-admin-purge-token-2026
+      - DATABASE_URL=postgresql://artdag:${POSTGRES_PASSWORD}@postgres:5432/artdag
+      - ADMIN_TOKEN=${ADMIN_TOKEN}
       # IPFS_API multiaddr - used for all IPFS operations (add, cat, pin)
       - IPFS_API=/dns/ipfs/tcp/5001
       - CACHE_DIR=/data/cache
@@ -102,7 +102,7 @@ services:
     command: sh -c "find /app -type d -name __pycache__ -exec rm -rf {} + 2>/dev/null; celery -A celery_app worker --loglevel=info -E"
     environment:
       - REDIS_URL=redis://redis:6379/5
-      - DATABASE_URL=postgresql://artdag:artdag@postgres:5432/artdag
+      - DATABASE_URL=postgresql://artdag:${POSTGRES_PASSWORD}@postgres:5432/artdag
       # IPFS_API multiaddr - used for all IPFS operations (add, cat, pin)
       - IPFS_API=/dns/ipfs/tcp/5001
       - CACHE_DIR=/data/cache
@@ -156,10 +156,10 @@ services:
     command: sh -c "cd /app && celery -A celery_app worker --loglevel=info -E -Q gpu,celery"
     environment:
       # GPU node is on different VPC - use public IPs for cross-node communication
-      - REDIS_URL=redis://138.68.142.139:16379/5
-      - DATABASE_URL=postgresql://artdag:artdag@138.68.142.139:15432/artdag
+      - REDIS_URL=redis://${L1_HOST}:16379/5
+      - DATABASE_URL=postgresql://artdag:${POSTGRES_PASSWORD}@${L1_HOST}:15432/artdag
       # Connect to shared IPFS node on CPU (via public IP)
-      - IPFS_API=/ip4/138.68.142.139/tcp/15001
+      - IPFS_API=/ip4/${L1_HOST}/tcp/15001
       # Gateway fallback for resilience
       - IPFS_GATEWAYS=https://ipfs.io,https://cloudflare-ipfs.com,https://dweb.link
       # Local cache is ephemeral (tmpfs or local volume)