diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 100644
index 0000000..8bf02b3
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1,42 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Self-hosted Gitea deployment using Docker Compose with a remote PostgreSQL database and automated daily backups to NAS storage.
+
+## Architecture
+
+Two-container setup via `docker-compose.yml`:
+
+- **gitea** — Main Gitea application (`gitea/gitea:latest`). Web UI on port 3008, SSH on port 2222. Connects to a remote PostgreSQL instance at `192.168.50.42:5432`.
+- **gitea-backup** — Alpine sidecar that installs `docker-cli`, sets up a cron job (2 AM daily), and runs `backup.sh` via `docker exec` into the gitea container.
+
+Backup files (`gitea-dump-YYYY-MM-DD_HHMM.zip`) are written to `/mnt/nasen/backup/gitea` (NAS mount) with 7-day retention.
+
+## Common Commands
+
+```bash
+# Start/stop services
+docker-compose up -d
+docker-compose down
+
+# View logs
+docker-compose logs -f gitea
+docker-compose logs -f gitea-backup
+
+# Run a manual backup
+docker exec gitea-backup /usr/local/bin/backup.sh
+
+# Check backup logs inside sidecar
+docker exec gitea-backup cat /var/log/backup.log
+
+# Access Gitea admin CLI
+docker exec -u git gitea /app/gitea/gitea admin [subcommand]
+```
+
+## Key Files
+
+- `docker-compose.yml` — Service definitions, environment config, volume mounts
+- `backup.sh` — Backup script: runs `gitea dump`, verifies output, enforces retention policy
diff --git a/backup.sh b/backup.sh
new file mode 100755
index 0000000..4e93a98
--- /dev/null
+++ b/backup.sh
@@ -0,0 +1,57 @@
+#!/bin/sh
+set -e
+
+BACKUP_DIR="/backup"
+RETAIN_DAYS="${BACKUP_RETAIN_DAYS:-7}"
+TIMESTAMP="$(date +%Y-%m-%d_%H%M)"
+BACKUP_FILE="gitea-dump-${TIMESTAMP}.zip"
+
+echo "========================================"
+echo "Gitea backup started at $(date)"
+echo "========================================"
+
+# Pre-flight check
+if ! docker inspect gitea >/dev/null 2>&1; then
+    echo "ERROR: gitea container not found or not running."
+    exit 1
+fi
+
+# Ensure backup directory exists inside gitea container
+docker exec -u git gitea sh -c "mkdir -p /tmp/backup"
+
+# Run gitea dump
+echo "Running gitea dump..."
+docker exec -u git -w /tmp gitea \
+    /app/gitea/gitea dump \
+    -c /data/gitea/conf/app.ini \
+    --file "/tmp/backup/${BACKUP_FILE}" \
+    --skip-log \
+    --type zip
+
+# Verify backup was created
+if [ ! -f "${BACKUP_DIR}/${BACKUP_FILE}" ]; then
+    echo "ERROR: Backup file not found at ${BACKUP_DIR}/${BACKUP_FILE}"
+    exit 1
+fi
+
+FILESIZE=$(stat -c%s "${BACKUP_DIR}/${BACKUP_FILE}" 2>/dev/null || stat -f%z "${BACKUP_DIR}/${BACKUP_FILE}" 2>/dev/null)
+echo "Backup created: ${BACKUP_FILE} (${FILESIZE} bytes)"
+
+# Retention: delete backups older than N days
+echo "Cleaning up backups older than ${RETAIN_DAYS} days..."
+DELETED=$(find "${BACKUP_DIR}" -name "gitea-dump-*.zip" -mtime "+${RETAIN_DAYS}" -print -delete)
+if [ -n "${DELETED}" ]; then
+    echo "Deleted old backups:"
+    echo "${DELETED}"
+else
+    echo "No old backups to delete."
+fi
+
+echo ""
+echo "Current backups:"
+ls -lh "${BACKUP_DIR}"/gitea-dump-*.zip 2>/dev/null || echo "(none)"
+
+echo ""
+echo "========================================"
+echo "Gitea backup completed at $(date)"
+echo "========================================"
diff --git a/docker-compose.yml b/docker-compose.yml
new file mode 100644
index 0000000..39ddf18
--- /dev/null
+++ b/docker-compose.yml
@@ -0,0 +1,47 @@
+services:
+  gitea:
+    image: gitea/gitea:latest
+    container_name: gitea
+    environment:
+      - USER_UID=1000
+      - USER_GID=1000
+      - GITEA__database__DB_TYPE=postgres
+      - GITEA__database__HOST=192.168.50.42:5432
+      - GITEA__database__NAME=gitea
+      - GITEA__database__USER=postgres
+      - GITEA__database__PASSWD=ratata,123
+    restart: unless-stopped
+    volumes:
+      - gitea_data:/data
+      - /etc/timezone:/etc/timezone:ro
+      - /etc/localtime:/etc/localtime:ro
+      - /mnt/nasen/backup/gitea:/tmp/backup
+    ports:
+      - "3008:3000"
+      - "2222:22"
+
+  gitea-backup:
+    image: alpine:3.21
+    container_name: gitea-backup
+    depends_on:
+      - gitea
+    restart: unless-stopped
+    environment:
+      - BACKUP_RETAIN_DAYS=7
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
+      - /mnt/nasen/backup/gitea:/backup
+      - ./backup.sh:/usr/local/bin/backup.sh:ro
+      - /etc/timezone:/etc/timezone:ro
+      - /etc/localtime:/etc/localtime:ro
+    entrypoint: /bin/sh
+    command:
+      - -c
+      - |
+        apk add --no-cache docker-cli
+        echo "0 2 * * * /usr/local/bin/backup.sh >> /var/log/backup.log 2>&1" > /etc/crontabs/root
+        touch /var/log/backup.log
+        crond -f -l 2
+
+volumes:
+  gitea_data: