Choose how to integrate Modular SSO

How you add Modular SSO depends on what signs users in to your app today.

Your app signs users in with	How Scalekit fits in	Guide
Your own code: your backend checks passwords or sends codes, and creates the session	Your backend calls the Scalekit SDK to start the login and to read the user from the callback	Quickstart, then Handle the callback and find the user
Auth0	You add Scalekit to Auth0 as an OpenID Connect (OIDC) provider. Auth0 keeps the session	Auth0
Amazon Cognito	You add Scalekit to your Cognito user pool as an OIDC identity provider. Cognito keeps the session	AWS Cognito
Firebase Authentication	You add Scalekit as an OIDC provider in Firebase, or sign the user in to Firebase from your backend after the Scalekit login	Firebase
Supabase Auth	You add Scalekit to Supabase as a custom OIDC provider. Supabase keeps the session	Supabase
Auth.js in a Next.js app	You add Scalekit to Auth.js as an OIDC provider	Add enterprise SSO to Next.js with Auth.js

With an auth system, that system talks to Scalekit and creates the session, so your app writes little or no Scalekit code. You still set up Scalekit the same way: put the environment in Modular Auth mode, create an organization for each customer, and have their IT admin connect their identity provider (IdP).

Your auth system isn’t listed? If it can add an OIDC provider, add Scalekit as one, using your environment URL as the issuer and your client ID and secret. Otherwise, use the SDK from your backend as the quickstart shows.

Whichever way you integrate, each customer needs an organization and a working connection. See Onboard an enterprise customer.