User Authentication in 2025: Stop Rolling Your Own

Authentication is a solved problem. Yet developers still spend weeks building login systems from scratch, making the same security mistakes that were solved a decade ago.

Here's the modern approach.

Why Not Roll Your Own?

Building authentication means handling password hashing, secure session management, CSRF protection, rate limiting, email verification flows, password resets, multi-factor authentication, OAuth integrations, and ongoing security updates.

Miss any of these, and you're vulnerable. Use a battle-tested solution instead.

NextAuth.js / Auth.js

Best for: Next.js projects, flexibility, self-hosted

// app/api/auth/[...nextauth]/route.js
import NextAuth from 'next-auth';
import GoogleProvider from 'next-auth/providers/google';

export const authOptions = {
  providers: [
    GoogleProvider({
      clientId: process.env.GOOGLE_CLIENT_ID,
      clientSecret: process.env.GOOGLE_CLIENT_SECRET,
    }),
  ],
  callbacks: {
    async session({ session, token }) {
      session.user.id = token.sub;
      return session;
    }
  }
};

const handler = NextAuth(authOptions);
export { handler as GET, handler as POST };

Clerk

Best for: Fast implementation, beautiful UI, managed service

Clerk handles the entire UI - sign in, sign up, user profile, MFA. You write almost no auth code:

import { SignedIn, SignedOut, UserButton } from '@clerk/nextjs';function Header() {
  return (
    <nav>
      <SignedIn>
        <UserButton afterSignOutUrl="/" />
      </SignedIn>
      <SignedOut>
        <a href="/sign-in">Sign in</a>
      </SignedOut>
    </nav>
  );
}

Security Checklist

Before going live: HTTPS everywhere, secure httpOnly cookies, CSRF protection, rate limiting on auth endpoints, password strength requirements, email verification, and audit logging.

The Recommendation

Just need auth working quickly? Use Clerk.

Want full control? NextAuth.js with a database adapter.

Already using Supabase? Use Supabase Auth.

Authentication is just the first step - you still need authorisation, rate limiting, and audit logging. But start with solid auth, and you're building on a secure foundation.

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Secure authentication is built into every app we develop at LogicLeap. User auth, API security, and proper access control - done right from day one.