Self-hosted auth & identity
Open-source identity providers and auth stacks instead of Auth0 or Okta.

Keycloak
Battle-tested open-source identity and access management.

Authentik
Flexible identity provider with flows, SSO, and proxy auth.

SuperTokens
Open-source auth with session management and optional managed cloud.

Logto
Open-source Auth0 alternative focused on OIDC and developer UX.

Authelia
Single sign-on and 2FA companion for reverse proxies.