AI Website Performance Scanner Build like speedscan.ai

I need a full-stack developer to create a site similar or better than https://speedscan.ai/, but focused solely on AI-powered website performance scans. Visitors receive five free scans; every request beyond that draws from a credit balance. Logged-in users must be able to store each report in their profile for later review.

Scope of the scan
• Single-click Website Performance Scan that digs into load-time health only.
• Track Time to First Byte (TTFB), First Contentful Paint (FCP) and full page load time for every URL tested.
• Generate a clear, shareable report summarising those three metrics alongside AI commentary and optimisation advice.

Platform workflow
1. Guest scans → counter stops further use after the fifth try and prompts sign-up / credit purchase.
2. Registered scans → save results in a personal dashboard, maintain complete scan history and let users compare “Before vs After.”
3. AI engine → produce insights, highlight bottlenecks and recommend fixes in plain language.
4. Monitoring layer → ping sites regularly, trigger downtime alerts and send performance-drop e-mails.

Key screens & features
• Home page with input box, live progress bar and animated scoring.
• User dashboard (history, report viewer, credit balance, payment page).
• Admin panel to set free-scan limit, manage credits and review uptime logs.

Deliverables
– Responsive web app (front end + back end + database schema).
– REST or GraphQL API powering the scanner, credit system and alerts.
– AI insight module (can leverage OpenAI, GPT-4, or similar).
– Deployment scripts and minimal documentation for self-hosting.
– Final demo with one real domain scanned, history saved and a comparison report generated.

Acceptance will be based on:
• Accurate capture of TTFB, FCP and full load time.
• Hard enforcement of the 5-scan limit for guests.
• Successful save / retrieve flow in the dashboard.
• Functional e-mail alerts on simulated downtime.

To prevent spam, Please mention what the bottom of the reference site says. I will personally compare it with each proposal to ensure you have checked the reference site.

If you’ve built Lighthouse, Web-Vitals or similar tools before, your experience will fit perfectly. Let me know your preferred stack and a rough timeline, and we’ll get started right away.