User Authentication Feature Development

The goal of this project is to develop a new feature—user authentication—for my application. I need a clean, secure module that allows visitors to register, log in, and manage their sessions with industry-standard security practices.

Please set up the full flow: account creation, sign-in, encrypted password storage, password reset, and session handling. The code should be well-documented so I can maintain it easily after delivery. I’m flexible on framework and language as long as the solution integrates smoothly with the rest of the app and follows current best practices such as hashing and salting, prepared statements or parameterised queries, and HTTPS-only cookies.

Deliverables
• Fully functional authentication module integrated into the existing codebase
• Clear setup and configuration instructions
• Brief hand-off notes covering dependencies, file structure, and key security considerations

Acceptance criteria
• New users can create an account and immediately sign in
• Existing users can authenticate and maintain a session without manual refresh
• Password reset generates a time-limited link and verifies ownership before allowing a change
• All credentials are stored using a modern hashing algorithm (e.g., bcrypt, Argon2)

Feel free to propose additional safeguards or enhancements if they will strengthen the overall security profile.