Authentication Patterns JWT Access and Refresh Tokens Short-lived access tokens (15 minutes) with longer-lived refresh tokens (7 days). Store refresh tokens in HTTP-only cookies. Auth Middleware OAuth2 Authorization Code Flow with PKCE RBAC Model Anti-Patterns - Storing JWTs in (vulnerable to XSS; use HTTP-only cookies) - Using symmetric secrets for JWTs across multiple services (use RS256 with key pairs) - Not validating , , and claims on token verification - Implementing custom password hashing instead of using bcrypt/argon2 - Missing CSRF protection on cookie-based authentication - Returni…