I’ve been building web applications for years, and I keep returning to a simple truth: the best tools feel like an extension of your thoughts. Lately, I’ve found myself consistently reaching for the combination of Svelte and Supabase. It started as an experiment, but it quickly became my go-to stack for projects that need to feel alive, responsive, and connected. The way these two technologies complement each other is nothing short of remarkable. If you’re aiming to build modern, real-time web apps without drowning in complexity, you’re in the right place.

Svelte shifts the heavy lifting from the browser to the compile step. Instead of using a virtual DOM, it writes code that surgically updates the DOM when your state changes. The result is incredibly fast, lean applications. Supabase acts as your entire backend, offering a real-time PostgreSQL database, authentication, and file storage right out of the box. It’s like getting a fully staffed kitchen while you focus on being the chef.

So, what happens when you bring them together? You get a development experience that is both powerful and surprisingly simple. The reactivity that is core to Svelte aligns perfectly with Supabase’s real-time capabilities. When a change happens in the database, your Svelte components can update instantly, as if they were always in sync.

Getting started is straightforward. First, you install the Supabase client library in your Svelte project.

npm install @supabase/supabase-js

Then, you create a client instance. I usually set this up in a separate file, like lib/supabaseClient.js, to keep things organized.

// lib/supabaseClient.js
import { createClient } from '@supabase/supabase-js'

const supabaseUrl = import.meta.env.VITE_SUPABASE_URL
const supabaseAnonKey = import.meta.env.VITE_SUPABASE_ANON_KEY

export const supabase = createClient(supabaseUrl, supabaseAnonKey)

This client is your gateway to everything Supabase offers. But how do we make the data appear in our Svelte components? This is where the magic begins. Svelte’s stores provide a perfect mechanism for holding state that can be reactive to changes from Supabase.

Imagine you’re building a live scoreboard. You don’t want users to refresh the page to see updates. You want the scores to change the moment they do in the database. Here’s a basic example of how you can set up a real-time subscription inside a Svelte component.

<script>
  import { onMount } from 'svelte';
  import { writable } from 'svelte/store';
  import { supabase } from '$lib/supabaseClient';

  let scores = writable([]);

  onMount(() => {
    // Subscribe to changes in the 'scores' table
    const subscription = supabase
      .from('scores')
      .on('*', (payload) => {
        console.log('Change received!', payload);
        // Update the store, which will reactively update the UI
        scores.update(currentScores => {
          // Logic to insert, update, or delete the score based on payload
          return updatedScores;
        });
      })
      .subscribe();

    // Cleanup the subscription when the component is destroyed
    return () => {
      subscription.unsubscribe();
    };
  });
</script>

{#each $scores as score}
  <div>
    {score.team_name}: {score.points}
  </div>
{/each}

Did you notice how the subscription is set up inside onMount? This is a crucial detail. It ensures the real-time connection is established when the component is added to the page and properly closed when it’s removed, preventing memory leaks.

What about user authentication? This is often a complex part of any app, but Supabase makes it remarkably simple. You can add email/password, social logins, and more with just a few lines of code. The state of the authenticated user can also be managed reactively.

// A store to hold the user session
export const user = writable(supabase.auth.user());
supabase.auth.onAuthStateChange((event, session) => {
  user.set(session?.user || null);
});

This pattern means that any component in your app can import the user store and immediately know if someone is logged in, and who they are. The UI can reactively show a login button or a user profile without you having to manually manage that state across your entire application.

The true power of this integration lies in its simplicity. You’re not writing extensive boilerplate code to connect a frontend framework to a backend service. You’re writing declarative code that describes what you want to happen. When the data changes in Supabase, your Svelte UI changes to match. It feels natural.

This approach is perfect for dashboards, collaborative tools, chat applications, or any project where data freshness is critical. You can build features that feel instantaneous, providing a much smoother experience for your users. The combination allows you, the developer, to focus on creating a great user interface and business logic, while the underlying infrastructure just works.

I encourage you to try this combination on your next project. Start with a simple idea and see how quickly you can bring it to life with live, interactive data. The developer experience is genuinely rewarding.

If you found this walk-through helpful, or if you have your own tips for using Svelte and Supabase, I’d love to hear from you. Please share your thoughts in the comments below, and feel free to share this article with other developers who might be exploring these fantastic tools.