AuthKit SDK for SvelteKit

[!WARNING] This is prerelease software. APIs may change without notice.

The official WorkOS AuthKit SDK for SvelteKit applications. Provides seamless authentication with minimal setup.

Features

• 🚀 Quick Setup - Get authenticated in under 5 minutes
• 🔒 Secure by Default - Session-based auth with encrypted cookies
• 🎯 Type Safe - Full TypeScript support with IntelliSense
• 🏗️ SvelteKit Native - Built for SvelteKit's architecture
• 🎨 Flexible - Easy to customize and extend
• 🐛 Developer Friendly - Clear errors and debug mode

Installation

npm install @workos/authkit-sveltekit

Quick Start

1. Set Environment Variables

Create a .env file in your project root:

WORKOS_CLIENT_ID=client_01234567890123456789012345
WORKOS_API_KEY=sk_test_1234567890
WORKOS_REDIRECT_URI=http://localhost:5173/auth/callback
WORKOS_COOKIE_PASSWORD=your-secure-password-at-least-32-chars

Note: Generate a secure password using openssl rand -base64 24

2. Update app.d.ts

/// <reference types="@sveltejs/kit" />

declare global {
  namespace App {
    interface Locals {
      auth: import('@workos/authkit-sveltekit').AuthKitAuth;
    }
  }
}

export {};

3. Add to hooks.server.ts

import { configureAuthKit, authKitHandle } from '@workos/authkit-sveltekit';
import { env } from '$env/dynamic/private';

// Configure AuthKit with SvelteKit's environment variables
configureAuthKit({
  clientId: env.WORKOS_CLIENT_ID,
  apiKey: env.WORKOS_API_KEY,
  redirectUri: env.WORKOS_REDIRECT_URI,
  cookiePassword: env.WORKOS_COOKIE_PASSWORD,
});

export const handle = authKitHandle();

Note: For simpler setups where you're using process.env, you can skip the configureAuthKit call and the SDK will automatically read from process.env.

4. Create Callback Route

Create src/routes/auth/callback/+server.ts:

import { authKit } from '@workos/authkit-sveltekit';

export const GET = authKit.handleCallback();

5. Protect Routes

In any +page.server.ts:

import { authKit } from '@workos/authkit-sveltekit';

export const load = authKit.withAuth(async ({ auth }) => {
  // auth.user is guaranteed to exist
  return {
    user: auth.user,
    organizationId: auth.organizationId,
    role: auth.role,
    permissions: auth.permissions,
  };
});

API Reference

Authentication Helpers

authKit.withAuth(handler)

Protect a route or action, redirecting unauthenticated users to sign in.

export const load = authKit.withAuth(async ({ auth, ...event }) => {
  // Your authenticated logic here
});

authKit.getUser(event)

Get the current user (nullable).

export const load = async (event) => {
  const user = await authKit.getUser(event);
  return { user };
};

authKit.getSignInUrl(options)

Get the WorkOS sign-in URL.

const signInUrl = authKit.getSignInUrl({
  returnTo: '/dashboard',
  organizationId: 'org_123', // optional
  loginHint: '[email protected]', // optional
});

authKit.getSignUpUrl(options)

Get the WorkOS sign-up URL.

const signUpUrl = authKit.getSignUpUrl({
  returnTo: '/dashboard',
  organizationId: 'org_123', // optional
  loginHint: '[email protected]', // optional
});

authKit.signOut(event)

Sign out the current user.

export const actions = {
  signout: async (event) => {
    return authKit.signOut(event);
  },
};

Hooks

authKitHandle(options)

SvelteKit handle function that manages authentication.

export const handle = authKitHandle({
  debug: true, // Enable debug logging
  onError: (error) => console.error('Auth error:', error),
});

Configuration

interface AuthKitConfig {
  clientId: string; // WorkOS Client ID
  apiKey: string; // WorkOS API Key
  redirectUri: string; // OAuth redirect URI
  cookiePassword: string; // Cookie encryption password (min 32 chars)
  cookieName?: string; // Custom cookie name (default: 'wos-session')
  cookieDomain?: string; // Cookie domain restriction
  cookieMaxAge?: number; // Cookie max age in seconds (default: 400 days)
}

Environment Variables

AuthKit supports multiple ways to configure environment variables in SvelteKit:

Option 1: Using SvelteKit's $env (Recommended)

// hooks.server.ts
import { configureAuthKit, authKitHandle } from '@workos/authkit-sveltekit';
import { env } from '$env/dynamic/private';

configureAuthKit({
  clientId: env.WORKOS_CLIENT_ID,
  apiKey: env.WORKOS_API_KEY,
  redirectUri: env.WORKOS_REDIRECT_URI,
  cookiePassword: env.WORKOS_COOKIE_PASSWORD,
});

export const handle = authKitHandle();

Option 2: Using Static Environment Variables

// hooks.server.ts
import { configureAuthKit, authKitHandle } from '@workos/authkit-sveltekit';
import { WORKOS_CLIENT_ID, WORKOS_API_KEY, WORKOS_REDIRECT_URI, WORKOS_COOKIE_PASSWORD } from '$env/static/private';

configureAuthKit({
  clientId: WORKOS_CLIENT_ID,
  apiKey: WORKOS_API_KEY,
  redirectUri: WORKOS_REDIRECT_URI,
  cookiePassword: WORKOS_COOKIE_PASSWORD,
});

export const handle = authKitHandle();

Option 3: Automatic Configuration (Node.js environments)

If your environment supports process.env, the SDK will automatically read configuration:

// hooks.server.ts
import { authKitHandle } from '@workos/authkit-sveltekit';

// No configureAuthKit needed - reads from process.env automatically
export const handle = authKitHandle();

Advanced Usage

Organization Switching

export const actions = {
  switchOrg: async (event) => {
    const formData = await event.request.formData();
    const orgId = formData.get('organizationId') as string;

    return authKit.switchOrganization(event, { organizationId: orgId });
  },
};

Custom Sign-in Page

<script lang="ts">
  import { authKit } from '@workos/authkit-sveltekit';

  // Note: These methods are async and should be called server-side
  // For client-side, pass the URL from a server load function
</script>

<!-- Use URLs generated server-side -->
<a href={data.signInUrl}>Sign In</a>
<a href={data.signUpUrl}>Sign Up</a>

Server-side load function:

// +page.server.ts
import { authKit } from '@workos/authkit-sveltekit';

export const load = async () => {
  return {
    signInUrl: await authKit.getSignInUrl({ returnTo: '/dashboard' }),
    signUpUrl: await authKit.getSignUpUrl({ returnTo: '/dashboard' }),
  };
};

Form Actions

Protect form actions the same way as load functions:

export const actions = {
  update: authKit.withAuth(async ({ auth, request }) => {
    const formData = await request.formData();
    // Process authenticated form submission
  }),
};

TypeScript

The SDK is fully typed. Access auth data with type safety:

import type { PageServerLoad } from './$types';

export const load: PageServerLoad = async ({ locals }) => {
  if (locals.auth.user) {
    // TypeScript knows user exists and its shape
    console.log(locals.auth.user.email);
    console.log(locals.auth.organizationId);
    console.log(locals.auth.role);
    console.log(locals.auth.permissions);
    console.log(locals.auth.accessToken);
  }
};

Debugging

Enable debug mode to see detailed logs:

export const handle = authKitHandle({ debug: true });

Error Handling

The SDK provides clear error messages:

Missing required environment variables: WORKOS_CLIENT_ID, WORKOS_API_KEY
Please add them to your .env file. See https://github.com/workos/authkit-sveltekit#setup for details.

License

MIT - see LICENSE for details.