Linux App Download Registration

I’m preparing a Linux-only desktop application for public release and need a straightforward way for users to both download it and create an account before first launch.

Scope of work
• Build an online download page that serves the .deb/.rpm and AppImage packages for my application.
• Implement a username-and-password registration flow. Users should enter their details, receive a confirmation e-mail, and then gain access to the download link.
• Store credentials securely in a lightweight backend (SQLite, PostgreSQL, or another open-source option you recommend).
• Provide an admin panel or simple CLI script so I can view, reset, or delete user accounts.
• Supply clear deployment instructions so I can install the solution on my own Linux VPS.

Nice-to-have (not required but welcome)
• Basic rate-limit or CAPTCHA on the registration form.
• Token-based licensing check inside the app that calls the server once on first run.

Deliverables
1. Source code for the registration portal and any supporting scripts.
2. Database schema and migration files.
3. Step-by-step setup documentation.
4. A brief hand-off call or recorded walkthrough (15-20 min).

I value clean, maintainable code and concise documentation. If you’ve built similar download or licensing systems for Linux desktop software, I’d love to see an example.