Cursor Software Tutorial: Adding User Authentication in an Evening

In this tutorial, we'll walk through how to use the Cursor AI code editor to quickly add user authentication to your web application. We'll be following the example from Matt Pal's video on X.com, where he describes adding auth to his app in a single evening using Cursor and Clerk.

Here's an overview of the video:

View original post on X.com

Took a crack at user auth—added in under an evening with Clerk.^[1]

Adding user authentication is often a tedious and time-consuming process for developers. But with the power of AI-assisted coding in Cursor, along with a user management service like Clerk, it's possible to implement a secure login system in just a few hours.

The Problem: Implementing User Auth From Scratch

Building user authentication into a web app typically involves several steps:

1. Setting up a database to store user credentials
2. Implementing signup and login forms
3. Securely hashing and storing passwords
4. Managing password reset flows
5. Handling session tokens and cookies

Coding all of this from scratch is a lot of work. There are many security considerations and edge cases to account for. As a developer, your time is better spent building your app's core functionality rather than reinventing the wheel with auth.

The Solution: Cursor + Clerk

Fortunately, we can leverage Cursor's AI coding capabilities along with the Clerk authentication service to add auth in a fraction of the time it would take to build it ourselves.

Here are the key steps, as demonstrated in the video:

1. Create a new Clerk account and application
2. Install the Clerk React SDK in your frontend codebase
3. Use Cursor to automatically generate the code for signup/login components
4. Customize the auth components to fit your app's design
5. On the backend, install Clerk's Node SDK to verify user JWTs
6. Use Cursor to add the JWT verification middleware to your API routes
7. Test the auth flow to ensure users can sign up, log in, and access protected routes

By using Cursor, you can simply describe what you want your auth system to do using natural language. Cursor will then generate the appropriate code, explain what the code does, and even suggest improvements and best practices.

For example, you could prompt Cursor with something like:

"Add a signup form component that collects the user's email and password, with fields for password confirmation and a submit button. The form should send a POST request to the /signup API route on submit."

Cursor will generate a React component for the signup form, explain the key parts of the code, and allow you to instantly insert it into your codebase. It can even update related files as needed, like adding the /signup route handler in your backend code.

Some key benefits of using Cursor for auth:

• Saves hours of development time
• Ensures you're following security best practices
• Avoids common pitfalls and edge cases
• Allows you to customize the auth flow to fit your app's needs

Caveats and Risks To Consider

While using an AI coding assistant like Cursor can dramatically speed up development, there are a few risks and caveats to keep in mind:

1. Always carefully review code generated by AI to ensure it's secure and fits your use case - don't blindly copy/paste!
2. Be mindful of the terms of service and data privacy policies of any third-party auth services you use
3. Thoroughly test your auth flow with different user roles and edge cases before deploying to production
4. Keep your auth service's private keys secure and never commit them to version control
5. Consider implementing additional security measures like two-factor authentication and suspicious login detection

Additional Auth Concepts To Consider

In addition to the core auth flow covered in the video, here are a few other concepts you may want to implement in your app:

Role-Based Access Control (RBAC)

RBAC allows you to define different levels of access for different types of users. For example, you may have roles like "admin", "editor", and "viewer" that grant specific permissions within your app.

With Cursor, you could prompt it to generate middleware that checks a user's assigned role and restricts access to certain API endpoints or UI components accordingly.

Social Login

Many users prefer to sign up for apps using their existing social media accounts like Google, Facebook, or Twitter. Clerk and other auth services make it easy to add social login options alongside traditional email/password auth.

You can prompt Cursor to add the necessary frontend buttons and backend logic to enable social login with just a few lines of natural language.

Auth in Server-Rendered Apps

If your app uses server-side rendering (e.g. with a framework like Next.js), you'll need to ensure that user auth state is properly shared between the server and client.

With Cursor, you can describe your app's architecture and rendering strategy, and it will provide appropriate code snippets and explanations for managing auth state across the stack.

Additional Cursor Capabilities

Beyond auth, Cursor's AI coding features can assist with virtually any aspect of web development. For example:

• Generating entire React components or pages with a few natural language prompts
• Automatically refactoring code to be more modular and reusable
• Adding inline documentation and explanations of complex code
• Detecting and fixing bugs and security vulnerabilities
• Providing intelligent code autocomplete and suggestions as you type
• Answering questions about your codebase and explaining how different pieces fit together

The more you use Cursor, the more it learns about your codebase and coding style. Over time, it can become an invaluable pair programming assistant that significantly boosts your productivity and code quality.

Getting Started With Cursor

To start using Cursor in your own projects:

1. Sign up for a free account at https://www.cursor.com
2. Download the Cursor desktop app for your OS
3. Open your project's codebase in Cursor
4. Start prompting Cursor with natural language requests to generate and modify code
5. Review Cursor's code explanations and suggestions to learn and improve your skills

You can refer to the Cursor documentation for more details on installation, setup, and usage: https://docs.cursor.com

There are also several helpful community resources, including:

• The Cursor Slack community, where you can ask questions and get support from other developers: https://cursor.slack.com
• The Cursor YouTube channel, with tutorial videos and demos: https://www.youtube.com/@cursor
• The Cursor blog, featuring case studies, tips, and new feature announcements: https://www.cursor.com/blog

Conclusion

Adding user authentication to a web app is just one of the many development tasks that Cursor can help streamline. By leveraging the power of AI-assisted coding, you can build features faster, catch bugs earlier, and level up your programming skills.

While there are risks and limitations to be aware of, the productivity boost from tools like Cursor is hard to overstate. It's an exciting time to be a developer, with AI opening up new possibilities for how we write and reason about code.

To see more examples of Cursor in action, check out Matt Pal's other videos on X.com: https://x.com/mattppal

Happy coding!

Citations:

1. https://www.youtube.com/watch?v=6J0k22CkcQ8
2. https://www.youtube.com/watch?v=Rgz6mX93C4Y
3. https://www.cursor.com
4. https://www.youtube.com/watch?v=CqkZ-ybl3lg
5. https://www.youtube.com/watch?v=y9mcrWktWd8
6. https://forum.cursor.com/t/basic-cursor-tutorial/289
7. https://www.datacamp.com/tutorial/cursor-ai-code-editor
8. https://www.youtube.com/playlist?list=PLWd-ys7mr3MxIEjLTmcCQ5mzXo3WonEGf