The UI of my Flutter app is already in place; what I need now is a solid and secure authentication layer powered by Firebase. The flow must cover email + password sign-up and log-in, email verification, log-out, and a password-reset process that sends the user an email with a reset link. I have no rigid preference for the navigation pattern, so you are free to hook into the existing routes in the way that feels most natural and maintainable. Besides Authentication, Firestore will also be part of the setup so user-related data can be stored or queried right after sign-up. Key things that matter to me are proper error handling, smooth transitions between auth states, and clean token management so users stay signed in securely without unexpected logouts. Your Dart code should be modular, well-commented, and easy to extend. Deliverables • Firebase project configuration with Authentication and Firestore (including basic security rules) • Flutter implementation of sign-up, log-in, log-out, email verification, and email-link password reset • Clear, maintainable Dart code organised by feature/folder • Brief documentation covering how to manage users, update rules, and run the project locally If you’ve shipped Flutter apps that rely on Firebase Auth before and you understand best practices around session security and navigation, I’d love to work with you.