ZITADEL is a cloud-based, open-source IAM platform built in Switzerland. The site describes it as a multi-tenant, API-first identity platform with comprehensive developer SDKs. Key features include single sign-on, multi-factor authentication and role-based access control. The site also highlights that ZITADEL has a large community (4,000+ GitHub stars) and is used in over 60 countries. (No specific founder or funding information is listed on the site.)