Supabase Migration for Production Backend

I’m midway through moving a live Node.js backend to Supabase and I’m determined to pull this off without any hiccups for our existing users. The job covers all critical pieces—database, authentication, and storage—so deep familiarity with Supabase Postgres, Row Level Security, Storage buckets, and the Auth API is essential.

Where things stand
• Current stack: Node.js with a traditional Postgres instance and a home-grown auth layer.
• Users: a healthy active base in production (so every second of downtime counts).
• Scope: migrate schema and data to Supabase Postgres, port auth to Supabase Auth (including social logins and JWT flow), and replicate file storage into Supabase Storage while preserving existing URLs.

What I need from you
1. A migration blueprint that outlines step-by-step tasks, cut-over strategy, and rollback options.
2. Scripts or tooling—Typescript preferred—to run the data copy, transform any columns, and validate counts/checksums.
3. Updates to our Node.js services so they switch seamlessly to Supabase client libraries and environment variables at the flip of a flag.
4. Post-migration verification covering data integrity, auth tokens, file accessibility, and performance benchmarks.
5. A short hand-off document so the internal team can operate and scale the new setup after you’re done.

Acceptance criteria
• Zero data loss and no broken auth sessions when we toggle traffic.
• Storage objects accessible through their original paths.
• Automated tests pass on the first production deploy.
• Monitoring dashboards (e.g., Grafana or Supabase Insights) show error rates unchanged or better within 24 h of go-live.

If you’ve already moved production workloads to Supabase and can talk through the edge cases—replication lag, RLS pitfalls, rate limits—I’d love to hear how you’d approach this move and an estimated timeline to get it done safely.