PHP/MySQL App Enhancement

I'm looking for a skilled developer to enhance my existing application. The project involves adding new features, improving performance, and updating the user interface.

Key Tasks:
- Implement user authentication and authorization
- Develop data analytics and reporting features
- Optimize application performance
- Fix UI bugs

The ideal candidate should have:
- Strong expertise in PHP and MySQL
- Proficiency in CSS for UI styling
- Experience in app performance optimization
- Previous work on similar feature implementations

Please provide examples of past work and relevant experience.