Web App Security Audit Needed

I'm seeking an ethical hacker to conduct a comprehensive security audit on my web application.

Ideal Skills:
- Proficiency in ethical hacking
- Expertise in security audits
- Experience with web application security
- Knowledge of penetration testing techniques
- Familiarity with vulnerability assessment tools

I need the hacker to identify any potential security threats and provide a detailed report with recommendations for improvement.

Please focus on thoroughly testing user authentication mechanisms.