n8n + Supabase: PostgreSQL, Authentication, and API All in One

We continue our series on n8n’s integration with backend services. Today’s focus is Supabase — a popular open-source Firebase alternative built on PostgreSQL. Supabase delivers everything a modern backend needs — DB, authentication, API, realtime — and integrates seamlessly with n8n.

What Is Supabase?

Supabase is a BaaS (Backend-as-a-Service) that brands itself as an “open-source Firebase alternative,” powered by PostgreSQL. It offers:

• 📦 PostgreSQL Database — a full-featured relational DB with SQL, indexes, functions, and transactions.
• 🔐 Auth — built-in authentication (email, OAuth, magic links).
• 📁 Storage — file storage with access control.
• ⚡ Edge Functions — serverless functions powered by Deno.
• 🔁 Realtime — subscriptions for database changes.
• 🌐 PostgREST API — automatic REST API based on the DB schema.

Advantages of Supabase

• PostgreSQL inside — mature and robust storage engine for any data.
• Automatic APIs — out-of-the-box CRUD endpoints for every table.
• Built-in auth and Row Level Security (RLS).
• Realtime support for live event-driven workflows.
• Open source — deploy locally or in the cloud.
• n8n support — via the native Supabase node.

Potential Limitations

• 🧪 Young project — evolving quickly, but its ecosystem is still smaller than Firebase.
• 🧩 RLS setup — powerful but requires knowledge of PostgreSQL and SQL policies.
• 🔧 Not NoSQL — schema matters, though JSON/JSONB provide flexibility.

How to Connect Supabase to n8n

1. Create a project in Supabase.
2. Go to Project Settings → API, and copy:
   • Project URL
   • Service Role Key or Anon Key
3. In n8n:
   • Create new credentials of type Supabase API.
   • Enter the URL and API key.
4. Use the Supabase node for database or auth operations.

What Can You Do with n8n + Supabase?

🧾 Database Operations:

• Get — read rows
• Insert — add new entries
• Update — modify existing data
• Delete — remove rows
• Custom Query — execute SQL

👤 Authentication Operations:

• Sign Up / Sign In
• Reset Password
• Get User Info

Example Automation Scenarios

1. Save website form submissions to Supabase

Workflow: Webhook → Supabase (Insert)

2. Notify on new order

Workflow: Cron → Supabase (Get where status = 'shipped') → Slack / Email

3. Welcome email after registration

Workflow: Supabase Webhook → Supabase (Get User) → Send Email

Supabase Features That Shine in Automation

Conclusion

Supabase is a modern, flexible backend service built on PostgreSQL — and it works beautifully with n8n. You can easily build powerful automations, manage users, store files, and respond to database events in real time. It’s especially handy for applications, startups, and internal tooling.

In the next article — Firebase, and how n8n integrates with its realtime database, auth, and functions.