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Use Juno with SvelteKit

Explore how to create a Juno project developed with SvelteKit.

Table of contents


This guide provides quickstart instructions for integrating Juno in two scenarios: starting a new project and adding Juno to an existing SvelteKit app.

Additionally, it covers how to develop against a production environment or locally.

Path A: Start a new project with a template

  1. Create a new project using the Juno quickstart CLI:
npm create juno@latest

Path B: Integrate Juno into an existing Next.js app

  1. Add the Juno SDK:

Navigate to your existing app directory and install Juno SDK:

cd your-existing-app
npm i @junobuild/core-peer

2. Configure Datastore

Production Path

To use production, set up a satellite and new collection:

  • Create a new satellite in the Juno's console.
  • After your project is ready, create a collection in your datastore, which we'll call demo, using the console.

Local Development Path

To develop with the local emulator, add a collection named demo within the file.

import { defineDevConfig } from "@junobuild/config";

export default defineDevConfig(() => ({
satellite: {
collections: {
db: [
collection: "demo",
read: "managed" as const,
write: "managed" as const,
memory: "stable" as const,
mutablePermissions: true
  • Once set, run the local emulator:
juno dev start
  • If the Juno admin CLI (required for deployment, configuration, or to run the emulator) is not installed yet, run:
npm i -g @junobuild/cli

3. Insert data from your app

Create a new file +layout.svelte in src/routes and initialize the library with the satellite ID you have created for production, or use jx5yt-yyaaa-aaaal-abzbq-cai if you are developing locally with the emulator.

import { onMount } from "svelte";
import { initSatellite } from "@junobuild/core";

onMount(async () => await initSatellite());

<slot />

Replace the existing content in your +page.svelte file in the same routes directory with the following code.

import { setDoc } from "@junobuild/core";

let doc;

const insert = async () =>
(doc = await setDoc({
collection: "demo",
doc: {
key: `my-key-${new Date().getTime()}`,
data: {
hello: "world"

<button on:click="{insert}">Insert a document</button>

{#if doc !== undefined}
<span>Key: {doc.key}</span>

5. Start the app

Start the app, go to http://localhost:5173 in a browser, click "Insert a document," and you should see the data successfully persisted in your satellite on the blockchain.

Note-taking app example

This example demonstrates how to quickly deploy a basic note-taking app that integrates Juno's core features:

  • Authentication: easy-to-use SDKs that support truly anonymous authentication.
  • Datastore: a simple key-pair database for storing user data and other information.
  • Storage: a file storage system to store and serve user-generated content, such as photos.

Using the Juno CLI, you can easily scaffold this app. To start, run the appropriate command based on your package manager:


npm create juno@latest


yarn create juno


pnpm create juno

Follow the CLI prompts to choose the note-taking app example and select local development. The CLI will manage all configurations and dependencies, allowing you to focus on exploring and customizing your app right away.


If you're looking to deploy your existing app or website developed with SvelteKit and Juno, this guide is for you.

1. Static site generation

The Internet Computer, including Juno, currently does not support Server Side Rendering. Therefore, it is recommended to generate a pre-rendered or client-side-only frontend application.

We suggest using the adapter-static option from SvelteKit and replacing the default adapter.

Remove and install the adapter:

npm rm @sveltejs/adapter-auto && npm i -D @sveltejs/adapter-static

Update the import in svelte.config.js file:

import adapter from "@sveltejs/adapter-static";

/** @type {import('@sveltejs/kit').Config} */
const config = {
kit: {
adapter: adapter()

export default config;

Create a file +layout.js in src/routes to set the prerender option:

export const prerender = true;

2. Set up a satellite

If you haven't created a satellite yet, go ahead and create a new one in the Juno's console.

3. Install Juno CLI and log in

Install the Juno command line interface by executing the following command in your terminal:

npm i -g @junobuild/cli

After the CLI is ready, log in to your satellite from your terminal to authenticate your device.

juno login

4. Deploy

Build your app:

npm run build

Deploy your project by running the following command from your project’s root folder:

juno deploy

When prompted to provide the name or path of the folder containing your built dapp files, answer build.

5. Open

Open your browser and you should see your deployed app or website.

juno open