SuperTokens

SuperTokens Core is the backend HTTP service at the center of SuperTokens, an open-source authentication system positioned as an alternative to Auth0, Firebase Auth, and AWS Cognito. It handles the core authentication logic and database operations, and is called by SuperTokens' Backend SDKs (available for Node.js, Go, Python, and others), which in turn expose sign-up, sign-in, sign-out, and session-refresh APIs that a Frontend SDK consumes to manage session tokens and render login UI.

It supports passwordless login, social login, email/password and phone/password authentication, session management, multi-factor authentication, multi-tenancy with per-organization enterprise SSO, user roles, and microservice-to-microservice authentication. Content outside the repository's ee/ directory is Apache-2.0 licensed; the ee/ directory (enterprise features) is licensed separately.

SuperTokens fits teams that want to self-host their authentication logic and data directly, using official SDKs for their stack, rather than depending on a fully hosted third-party identity provider.