Clerk provides an advanced authentication system that simplifies the process for developers by offering a complete solution that can be integrated into projects rapidly while ensuring an exceptional user experience. The system's infrastructure is designed to manage complex tasks such as protecting sensitive data, integrating with third-party services, and handling failures, enabling scalability to support millions of users. Developers have the option to use self-hosted authentication, which requires managing their own infrastructure, or opt for Clerk-hosted solutions that handle all authentication responsibilities and integrate with Backend-as-a-Service platforms like Firebase. Clerk's authentication services are efficiently powered by Google Cloud, featuring scalable APIs and background job management to maintain responsiveness. The system supports SMS, email, and OAuth without additional integration costs, and includes built-in features like bot detection. Developers can also choose to integrate their infrastructure, using their own email or SMS servers, while Clerk offers shared DNS and OAuth configurations for quick onboarding. Production instances ensure security by hosting the Frontend API as a subdomain of the application’s origin, maintaining user security across all authentication flows.