An Easy Recap of Supabase Essentials

Source: Dev.to

Introduction

Picture this: you’re building your next project and need authentication, a database, and maybe storage. You could spend days configuring PostgreSQL, setting up auth from scratch, and managing deployment—or you could have it all running in under 5 minutes.

In the modern coding era, tools like Supabase and Firebase are popular because they solve this exact problem. They let you ship fast without wrestling with infrastructure.

When you combine Supabase with your own NestJS backend, you don’t sacrifice control for speed—you get both. You retain full control over database logic, custom business rules, your own auth flow, and the ability to scale exactly how you want. No vendor lock‑in, no “this feature isn’t supported” roadblocks.

In this post, we’ll set up Supabase as the foundation for a NestJS API that gives you the best of both worlds.

What Makes Supabase Special

Supabase provides a production‑grade PostgreSQL database with three ways to access it:

• Direct connection – Connect with any Postgres client using the connection string (this is what we’ll use with Drizzle).
• REST API – PostgREST automatically generates a RESTful API for your tables—no backend needed.
• Realtime subscriptions – Listen to database changes in real time (think collaborative docs, live dashboards).

This flexibility lets you start with a direct connection for your NestJS API, prototype a quick feature via the REST API, or enable live updates with realtime subscriptions—all on the same database.

Supabase Auth

Supabase Auth handles everything you’d expect:

• Email/password and magic links
• OAuth providers (Google, GitHub, etc.)
• JWT token generation and validation
• User management and sessions

Because Supabase stores auth data in the auth schema of the same database, you can join auth tables in your queries, extend user profiles, or add custom claims—all in PostgreSQL.

Row‑Level Security (RLS)

Imagine you have a transactions table. Normally you’d write backend logic to ensure users can only see their own transactions. With RLS, you write that rule once at the database level:

CREATE POLICY "Users can only see their own transactions"
ON transactions FOR SELECT
USING (auth.uid() = user_id);

Now the database automatically enforces this rule. Whether you access the data via your NestJS API, the REST API, or directly, users can only see their own data. No leaked queries, no forgotten permission checks in your code.

Getting Started with Supabase

1. Create a new project

   • Go to and sign in (or create an account).
   • Click New Project.
   • Choose an organization or create a new one.

2. Configure your project

   • Name your project (e.g., Finance-API).
   • Set a database password using the Generate a password button. Save this password securely (e.g., in a .env file).
   • Select a region close to your users to minimize latency.

3. Provision the project

   • Click Create new project and wait 2–3 minutes while Supabase provisions PostgreSQL, Auth, and related services.
   • Once ready, you’ll see the dashboard with connection details, API keys, and database info.

Understanding Supabase API Keys

Supabase provides two API keys, but for this tutorial we’ll use the direct PostgreSQL connection string with Drizzle, not the keys.

Note: For this series we connect NestJS to Supabase using the connection string. If you later add a React frontend that reads data directly from Supabase, you’d use the publishable key there.

What You’ve Learned

• Why Supabase + NestJS is powerful: Speed of a BaaS with the control of a custom backend.
• How Postgres and Auth integrate: Row‑Level Security lets the database enforce permissions automatically, eliminating whole classes of security bugs.
• Connection options: Direct connection (used with Drizzle), REST API, and Realtime subscriptions each serve different use cases.
• Project readiness: Your Supabase project is live and waiting for a connection.

Next Steps

Set up a NestJS application and configure a module to handle the database credentials securely. Use the connection string to connect Drizzle to your Supabase instance, then start building your API.

💡 See you there! 🚀