diff --git a/Dockerfile.cron b/Dockerfile.cron
new file mode 100644
index 0000000..b75fcf4
--- /dev/null
+++ b/Dockerfile.cron
@@ -0,0 +1,23 @@
+FROM --platform=$TARGETPLATFORM python:3.12-slim-bookworm
+
+ENV PYTHONDONTWRITEBYTECODE=1 \
+    PYTHONUNBUFFERED=1 \
+    PIP_NO_CACHE_DIR=1
+
+WORKDIR /app
+
+# Install Python dependencies first to leverage layer caching.
+COPY requirements.txt ./
+RUN pip install --no-cache-dir -r requirements.txt
+
+# Copy application source.
+COPY jira_jotty_sync.py ./
+COPY sync_config.json.template ./
+
+# Run as non-root for better container security.
+RUN useradd --create-home --uid 10001 appuser && chown -R appuser:appuser /app
+USER appuser
+
+# Run every 5 minutes via cron
+CMD echo "*/5 * * * * cd /app && python jira_jotty_sync.py --direction both >> /tmp/sync.log 2>&1" | crontab - && \
+    crond -f
diff --git a/jira_jotty_sync.py b/jira_jotty_sync.py
index 8823cc0..79e6e39 100644
--- a/jira_jotty_sync.py
+++ b/jira_jotty_sync.py
@@ -14,11 +14,54 @@ Usage:
 Configuration is stored in sync_config.json (see template below).
 """
 
+import os
+import subprocess
+import sys
+
+# ---------------------------------------------------------------------------
+# Auto-venv setup: if not running inside a virtual environment, create one,
+# install requirements, and re-execute this script with the venv Python.
+# ---------------------------------------------------------------------------
+def _ensure_venv():
+    """Create .venv if missing, install requirements, then re-execute self."""
+    # Check if we're already in a venv
+    in_venv = getattr(sys, "prefix", None) != getattr(sys, "base_prefix", None)
+    if in_venv:
+        return
+
+    script_dir = os.path.dirname(os.path.abspath(__file__))
+    venv_path = os.path.join(script_dir, ".venv")
+    requirements_file = os.path.join(script_dir, "requirements.txt")
+
+    # Create virtual environment if it doesn't exist
+    if not os.path.isdir(venv_path):
+        print(f"[setup] Creating virtual environment in {venv_path} ...")
+        subprocess.run([sys.executable, "-m", "venv", venv_path], check=True)
+
+    # Determine the venv python executable (cross-platform)
+    if os.name == "nt":  # Windows
+        venv_python = os.path.join(venv_path, "Scripts", "python.exe")
+    else:
+        venv_python = os.path.join(venv_path, "bin", "python")
+
+    # Install requirements if not already installed
+    print(f"[setup] Installing dependencies ...")
+    subprocess.run(
+        [venv_python, "-m", "pip", "install", "--upgrade", "-r", requirements_file],
+        check=True,
+    )
+
+    # Re-execute this script using the venv Python
+    print("[setup] Relaunching with virtual environment ...")
+    sys.exit(subprocess.call([venv_python, __file__] + sys.argv[1:]))
+
+
+_ensure_venv()
+del _ensure_venv  # Clean up namespace
+
 import argparse
 import json
 import logging
-import os
-import sys
 import time
 from dataclasses import dataclass, field
 from typing import Optional