mg-railway-db-backup - SKILL.md Agent Skill

name: mg-railway-db-backup description: Backup a PostgreSQL database from a Railway environment. Use when the user asks to "backup db", "dump database", "save db from railway", "backup railway database", or "export db".

Railway DB Backup

Backup a PostgreSQL database from a Railway environment to a local file.

Inputs

Ask the user if not provided:

project — Railway project name
environment — Railway environment name to backup from (e.g., demo, production)

Procedure

Link to the correct project and environment using Railway MCP link-environment tool:
- workspacePath:
- environmentName:
Ensure output directory exists:
```
mkdir -p <project-root>/.claude/local
```

Run pg_dump — credentials piped from Railway CLI (never write credential values in commands):

VARS=$(railway variables -s Postgres -e <environment> --kv 2>/dev/null) && \
export PGPASSWORD=$(echo "$VARS" | grep '^PGPASSWORD=' | cut -d= -f2-) && \
PGUSER=$(echo "$VARS" | grep '^PGUSER=' | cut -d= -f2-) && \
PGDATABASE=$(echo "$VARS" | grep '^PGDATABASE=' | cut -d= -f2-) && \
DB_URL=$(echo "$VARS" | grep '^DATABASE_PUBLIC_URL=' | cut -d= -f2-) && \
PGHOST=$(echo "$DB_URL" | sed 's|postgresql://[^@]*@||;s|:.*||') && \
PGPORT=$(echo "$DB_URL" | sed 's|.*:||;s|/.*||') && \
pg_dump -h "$PGHOST" -p "$PGPORT" -U "$PGUSER" -d "$PGDATABASE" \
  --no-owner --no-acl -F c \
  | gzip > <project-root>/.claude/local/<project>-<environment>-backup-$(date +%Y%m%d-%H%M%S).dump.gz

This reads credentials from railway variables into shell vars at runtime — no secrets ever appear in the command text.

Verify the backup file exists and report path + size to the user.

Notes

Railway runs PostgreSQL 17 — if local pg_dump version is too old, use the one from postgresql@17 homebrew package
Backup format is custom (-F c) for efficient restore with pg_restore
--no-owner --no-acl strips ownership/permissions for portable restores
Backups are stored in .claude/local/ which is git-ignored