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+---
+name: ship-binary
+description: Upload and deploy a pre-built binary to a ship VPS. Handles port allocation, systemd service, env vars, Caddy config, and SQLite backup. Use when deploying a Go binary or other compiled executable.
+argument-hint: "<path-to-binary> <app-name> [host-nickname]"
+---
+
+# ship-binary
+
+Upload a pre-built binary and deploy it as a systemd service with Caddy reverse proxy.
+
+## Read Config
+
+```bash
+python3 -c "
+import json, os
+cfg = json.load(open(os.path.expanduser('~/.config/ship/config.json')))
+nick = '<nickname-or-default>'
+h = cfg['hosts'].get(nick, cfg['hosts'][cfg['default']])
+print(h['host'])
+print(h['domain'])
+"
+```
+
+## Inputs
+
+- **Binary path** — local path to the compiled binary
+- **App name** — short lowercase name, becomes the service name and subdomain (e.g. `foodtracker`)
+- **Domain** — defaults to `<app-name>.<base-domain>` from config, ask if different
+- **Env vars** — ask if there are any env vars to set (beyond PORT/SHIP_NAME/SHIP_URL)
+- **Host** — use default unless specified
+
+## Steps
+
+### 1. Check if app already exists
+
+```bash
+ssh <host> "test -f /etc/ship/ports/<app-name> && echo exists || echo new"
+```
+
+This determines whether to allocate a new port or reuse the existing one.
+
+### 2. Backup SQLite databases (if app exists)
+
+Before touching anything, check for SQLite files in the app's data directory:
+
+```bash
+ssh <host> "find /var/lib/<app-name>/ -name '*.db' 2>/dev/null"
+```
+
+If any `.db` files are found, back them up:
+
+```bash
+ssh <host> "sudo mkdir -p /var/lib/<app-name>/backups && sudo cp /var/lib/<app-name>/data/<name>.db /var/lib/<app-name>/backups/<name>-\$(date +%Y%m%d-%H%M%S).db"
+```
+
+Tell the user what was backed up before proceeding.
+
+### 3. Allocate or retrieve port
+
+**New app** — find the highest port in use and add 1:
+```bash
+ssh <host> "sudo bash -c 'max=9000; for f in /etc/ship/ports/*; do p=\$(cat \$f 2>/dev/null); [ \"\$p\" -gt \"\$max\" ] && max=\$p; done; port=\$((max+1)); echo \$port | tee /etc/ship/ports/<app-name>; echo \$port'"
+```
+
+**Existing app** — reuse the existing port:
+```bash
+ssh <host> "cat /etc/ship/ports/<app-name>"
+```
+
+### 4. Upload binary
+
+```bash
+scp <binary-path> <host>:/tmp/<app-name>
+ssh <host> "sudo mv /tmp/<app-name> /usr/local/bin/<app-name> && sudo chmod +x /usr/local/bin/<app-name>"
+```
+
+### 5. Create work directory and service user
+
+```bash
+ssh <host> "sudo mkdir -p /var/lib/<app-name>/data && sudo useradd -r -s /bin/false <app-name> 2>/dev/null || true && sudo chown -R <app-name>:<app-name> /var/lib/<app-name>"
+```
+
+### 6. Write env file
+
+Build the env file content merging ship-managed vars with any user-provided vars.
+If the file already exists, read it first and merge (new values win, old values survive):
+
+```bash
+ssh <host> "sudo cat /etc/ship/env/<app-name>.env 2>/dev/null"
+```
+
+Then write merged result:
+```bash
+ssh <host> "sudo tee /etc/ship/env/<app-name>.env > /dev/null << 'EOF'
+PORT=<port>
+SHIP_NAME=<app-name>
+SHIP_URL=https://<domain>
+<user-env-vars>
+EOF
+sudo chmod 600 /etc/ship/env/<app-name>.env"
+```
+
+### 7. Write systemd unit
+
+```bash
+ssh <host> "sudo tee /etc/systemd/system/<app-name>.service > /dev/null << 'EOF'
+[Unit]
+Description=<app-name>
+After=network.target
+
+[Service]
+Type=simple
+User=<app-name>
+WorkingDirectory=/var/lib/<app-name>
+EnvironmentFile=/etc/ship/env/<app-name>.env
+ExecStart=/usr/local/bin/<app-name>
+Restart=always
+RestartSec=5s
+NoNewPrivileges=true
+PrivateTmp=true
+
+[Install]
+WantedBy=multi-user.target
+EOF"
+```
+
+### 8. Start or restart service
+
+```bash
+ssh <host> "sudo systemctl daemon-reload"
+```
+
+**New app:**
+```bash
+ssh <host> "sudo systemctl enable --now <app-name>"
+```
+
+**Existing app:**
+```bash
+ssh <host> "sudo systemctl restart <app-name>"
+```
+
+### 9. Write Caddy config
+
+```bash
+ssh <host> "sudo tee /etc/caddy/sites-enabled/<app-name>.caddy > /dev/null << 'EOF'
+<domain> {
+    reverse_proxy 127.0.0.1:<port>
+}
+EOF
+sudo systemctl reload caddy"
+```
+
+### 10. Confirm
+
+Tell the user:
+- App name, URL, and port
+- Whether it was a new deploy or update
+- Any SQLite backups made
+- Any env vars set
+
+## Notes
+
+- Always back up SQLite before swapping the binary
+- Always merge env vars — never replace the whole file
+- Use `systemctl restart` for existing apps, `enable --now` for new ones
+- The data directory `/var/lib/<app-name>/data/` persists across deploys
+- If the user doesn't specify env vars, ask if they need any before deploying