diff --git a/README.md b/README.md
index 534ff1e..63d76cf 100644
--- a/README.md
+++ b/README.md
@@ -73,3 +73,20 @@ Notes
 - Core billing/export/report workflow is now operational.
 - Email log table records invoice, revenue report, and accounting package sends.
 
+
+## Installer
+
+From the project root:
+
+```bash
+chmod +x install.sh
+./install.sh
+
+## Installer
+
+From the project root:
+
+chmod +x install.sh
+./install.sh
+
+The installer will install dependencies, configure MariaDB, create the database, and start the service.
diff --git a/backend/app.py b/backend/app.py
index e983606..bbf8543 100644
--- a/backend/app.py
+++ b/backend/app.py
@@ -4,6 +4,7 @@ from utils import generate_client_code, generate_service_code
 from datetime import datetime, timezone
 from zoneinfo import ZoneInfo
 from decimal import Decimal, InvalidOperation
+from pathlib import Path
 from email.message import EmailMessage
 
 from io import BytesIO, StringIO
@@ -22,9 +23,12 @@ app = Flask(
 
 LOCAL_TZ = ZoneInfo("America/Toronto")
 
+BASE_DIR = Path(__file__).resolve().parent.parent
+
+
 def load_version():
     try:
-        with open("/home/def/otb_billing/VERSION", "r") as f:
+        with open(BASE_DIR / "VERSION", "r") as f:
             return f.read().strip()
     except Exception:
         return "unknown"
@@ -1389,7 +1393,7 @@ def export_invoices_pdf_zip():
 
         logo_url = (settings.get("business_logo_url") or "").strip()
         if logo_url.startswith("/static/"):
-            local_logo_path = "/home/def/otb_billing" + logo_url
+            local_logo_path = str(BASE_DIR) + logo_url
             try:
                 pdf.drawImage(ImageReader(local_logo_path), left, y - 35, width=42, height=42, preserveAspectRatio=True, mask='auto')
             except Exception:
@@ -1879,7 +1883,7 @@ def invoice_pdf(invoice_id):
 
     logo_url = (settings.get("business_logo_url") or "").strip()
     if logo_url.startswith("/static/"):
-        local_logo_path = "/home/def/otb_billing" + logo_url
+        local_logo_path = str(BASE_DIR) + logo_url
         try:
             pdf.drawImage(ImageReader(local_logo_path), left, y - 35, width=42, height=42, preserveAspectRatio=True, mask='auto')
         except Exception:
diff --git a/backend/db.py b/backend/db.py
index a10f72b..81efa4b 100644
--- a/backend/db.py
+++ b/backend/db.py
@@ -1,11 +1,26 @@
+import os
 import mysql.connector
-from config import Config
+
 
 def get_db_connection():
-    return mysql.connector.connect(
-        host=Config.DB_HOST,
-        port=Config.DB_PORT,
-        user=Config.DB_USER,
-        password=Config.DB_PASSWORD,
-        database=Config.DB_NAME
-    )
+    host = os.getenv("OTB_BILLING_DB_HOST", "127.0.0.1")
+    port = int(os.getenv("OTB_BILLING_DB_PORT", "3306"))
+    database = os.getenv("OTB_BILLING_DB_NAME", "otb_billing")
+    user = os.getenv("OTB_BILLING_DB_USER", "otb_billing")
+    password = os.getenv("OTB_BILLING_DB_PASSWORD", "")
+    unix_socket = os.getenv("OTB_BILLING_DB_SOCKET", "").strip()
+
+    kwargs = {
+        "database": database,
+        "user": user,
+        "password": password,
+        "autocommit": False,
+    }
+
+    if unix_socket:
+        kwargs["unix_socket"] = unix_socket
+    else:
+        kwargs["host"] = host
+        kwargs["port"] = port
+
+    return mysql.connector.connect(**kwargs)
diff --git a/install.sh b/install.sh
new file mode 100755
index 0000000..a15eb51
--- /dev/null
+++ b/install.sh
@@ -0,0 +1,143 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+APP_NAME="otb_billing"
+APP_USER_DEFAULT="${SUDO_USER:-$USER}"
+APP_ROOT_DEFAULT="/opt/otb_billing"
+ENV_DIR="/etc/otb_billing"
+ENV_FILE="${ENV_DIR}/otb_billing.env"
+SERVICE_NAME="otb-billing"
+SCHEMA_FILE="sql/schema_v0.0.2.sql"
+
+if [[ ! -f "$SCHEMA_FILE" ]]; then
+  echo "ERROR: $SCHEMA_FILE not found. Run this from the repo root."
+  exit 1
+fi
+
+echo "=================================================="
+echo "OTB Billing installer"
+echo "=================================================="
+
+read -rp "Install app user [${APP_USER_DEFAULT}]: " APP_USER
+APP_USER="${APP_USER:-$APP_USER_DEFAULT}"
+
+read -rp "Install path [${APP_ROOT_DEFAULT}]: " APP_ROOT
+APP_ROOT="${APP_ROOT:-$APP_ROOT_DEFAULT}"
+
+read -rp "MariaDB database name [otb_billing]: " DB_NAME
+DB_NAME="${DB_NAME:-otb_billing}"
+
+read -rp "MariaDB database user [otb_billing]: " DB_USER
+DB_USER="${DB_USER:-otb_billing}"
+
+read -rsp "MariaDB database password: " DB_PASS
+echo
+if [[ -z "$DB_PASS" ]]; then
+  echo "ERROR: database password cannot be blank."
+  exit 1
+fi
+
+read -rp "App listen host [0.0.0.0]: " APP_HOST
+APP_HOST="${APP_HOST:-0.0.0.0}"
+
+read -rp "App listen port [5050]: " APP_PORT
+APP_PORT="${APP_PORT:-5050}"
+
+echo
+echo "Installing system packages..."
+sudo apt-get update
+sudo DEBIAN_FRONTEND=noninteractive apt-get install -y \
+  python3 python3-venv python3-pip mariadb-server rsync
+
+echo
+echo "Creating app directory..."
+sudo mkdir -p "$APP_ROOT"
+sudo rsync -a --delete \
+  --exclude '.git' \
+  --exclude '__pycache__' \
+  --exclude 'releases' \
+  --exclude '*.pyc' \
+  ./ "$APP_ROOT"/
+
+sudo chown -R "$APP_USER":"$APP_USER" "$APP_ROOT"
+
+echo
+echo "Creating Python virtualenv..."
+sudo -u "$APP_USER" python3 -m venv "$APP_ROOT/venv"
+sudo -u "$APP_USER" "$APP_ROOT/venv/bin/pip" install --upgrade pip
+sudo -u "$APP_USER" "$APP_ROOT/venv/bin/pip" install -r "$APP_ROOT/requirements.txt"
+
+echo
+echo "Ensuring MariaDB is running..."
+sudo systemctl enable mariadb
+sudo systemctl restart mariadb
+
+echo
+echo "Creating MariaDB database and user..."
+sudo mysql <<SQL
+CREATE DATABASE IF NOT EXISTS \`${DB_NAME}\` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+CREATE USER IF NOT EXISTS '${DB_USER}'@'localhost' IDENTIFIED BY '${DB_PASS}';
+ALTER USER '${DB_USER}'@'localhost' IDENTIFIED BY '${DB_PASS}';
+GRANT ALL PRIVILEGES ON \`${DB_NAME}\`.* TO '${DB_USER}'@'localhost';
+FLUSH PRIVILEGES;
+SQL
+
+echo
+echo "Importing schema..."
+sudo mysql "$DB_NAME" < "$APP_ROOT/$SCHEMA_FILE"
+
+echo
+echo "Writing environment file..."
+sudo mkdir -p "$ENV_DIR"
+sudo tee "$ENV_FILE" >/dev/null <<ENVEOF
+OTB_BILLING_DB_HOST=127.0.0.1
+OTB_BILLING_DB_PORT=3306
+OTB_BILLING_DB_NAME=${DB_NAME}
+OTB_BILLING_DB_USER=${DB_USER}
+OTB_BILLING_DB_PASSWORD=${DB_PASS}
+FLASK_ENV=production
+HOST=${APP_HOST}
+PORT=${APP_PORT}
+ENVEOF
+sudo chmod 600 "$ENV_FILE"
+
+echo
+echo "Creating systemd service..."
+sudo tee "/etc/systemd/system/${SERVICE_NAME}.service" >/dev/null <<SERVICEEOF
+[Unit]
+Description=OTB Billing Flask App
+After=network.target mariadb.service
+Requires=mariadb.service
+
+[Service]
+Type=simple
+User=${APP_USER}
+WorkingDirectory=${APP_ROOT}
+EnvironmentFile=${ENV_FILE}
+ExecStart=${APP_ROOT}/venv/bin/python ${APP_ROOT}/backend/app.py
+Restart=always
+RestartSec=3
+
+[Install]
+WantedBy=multi-user.target
+SERVICEEOF
+
+echo
+echo "Enabling service..."
+sudo systemctl daemon-reload
+sudo systemctl enable "${SERVICE_NAME}"
+sudo systemctl restart "${SERVICE_NAME}"
+
+echo
+echo "Verifying service..."
+sudo systemctl --no-pager --full status "${SERVICE_NAME}" || true
+
+echo
+echo "Installer complete."
+echo "App path: ${APP_ROOT}"
+echo "Service: ${SERVICE_NAME}"
+echo "URL: http://${APP_HOST}:${APP_PORT}"
+echo
+echo "Useful commands:"
+echo "  sudo systemctl status ${SERVICE_NAME}"
+echo "  sudo journalctl -u ${SERVICE_NAME} -f"