Implement robust authentication and authorization frameworks beyond basic JWT — including OAuth 2.0 / OpenID Connect, SSO integrations, session management, token lifecycle (refresh/rotation/revocation), and role-based / attribute-based access control (RBAC/ABAC). Python Backend (Primary): Strong, hands-on experience building backend services with FastAPI / Flask / Django — async patterns, dependency injection, middleware, API versioning, testing, and production deployment.