Clerk
Auth that actually ships with your UI
Next.js / Auth · Freemium
What's Good
Integration with Next.js is exceptional: middleware handles route protection, hooks provide user state, and Server Components work seamlessly. Multi-factor authentication, social logins, and organization management are included.
The Catch
Loud Catch: Clerk is a paid auth product with a free tier that evaporates as MAUs grow. You are outsourcing login UI and session logic; customization is the Clerk way or a fight. This is not the OSS auth library.
Verdict
Auth-as-a-feature ships faster than auth-as-a-library.
Embed
[](https://stackgems.com/gems/clerk)