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Sadegh shojaye fard
Sadegh shojaye fard

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Building a Production-Ready Authentication System in Next.js, Without Reinventing the Wheel

IdentityUser is a production-ready authentication starter kit for Next.js.

It gives you full ownership of auth logic, strong security defaults, and real-world features — without hiding everything behind abstractions or SaaS services.


Authentication is one of those problems every serious application must solve — yet almost no one enjoys building it from scratch.

You start with a simple login form…

Then suddenly you’re dealing with password hashing, session persistence, email verification, OTPs, 2FA, brute-force protection, password resets, expiration policies, and security edge cases you didn’t even know existed.

That’s exactly why I built IdentityUser.


What Is IdentityUser?

IdentityUser is a lightweight but powerful authentication starter kit for Next.js.

It’s not a hosted service.

It’s not a black-box SaaS.

And it’s not just a few helper functions.

Instead, IdentityUser copies a complete, production-ready authentication module directly into your project, giving you:

  • Full ownership
  • Full control
  • Full transparency

Think of it as:

“What authentication should look like if you were building a serious product — but didn’t want to spend weeks reinventing it.”


Why I Built It

Most authentication libraries fall into one of two extremes:

  • 🔹 Too simple — great for demos, terrible for real products
  • 🔹 Too abstract — hard to customize, debug, or truly trust

I wanted something different:

  • Explicit code over magic
  • Strong security defaults
  • Clear separation between authentication and authorization
  • Designed for real-world Next.js apps, not just tutorials

So IdentityUser was built around production needs, not theoretical examples.


Core Design Principles

IdentityUser is built on a few key ideas:

✅ Ownership over abstraction

All logic lives inside your project — not hidden behind a package API.

✅ Security-first defaults

Password policies, throttling, session rules, and verification flows are enabled by design — not optional afterthoughts.

✅ Modular & extensible

Every feature is isolated and replaceable. Remove what you don’t need, extend what you do.

✅ Next.js-native

Designed specifically for Next.js App Router, Server Actions, and modern authentication patterns.


Key Features

🔐 Authentication Methods

IdentityUser supports multiple secure login flows:

  • Username / Email + Password
  • OTP login (Email or Phone)
  • Two-Factor Authentication (TOTP)
  • Recovery code login
  • Secure fallback login when 2FA is unavailable

🧠 Smart 2FA Experience

  • Remember This Browser

    • Trusted devices can bypass 2FA for a configurable period
  • Fallback Login

    • Temporary email-based access
    • Automatically disables 2FA after successful fallback
    • Prevents permanent account lockouts

🔑 Advanced Password Policies

  • Password complexity rules
  • Password history (prevents reuse)
  • Password expiration with forced reset
  • Mandatory password change flow when expired

🚦 Rate Limiting & Abuse Protection

Built-in limiters protect against:

  • Brute-force login attempts
  • OTP and verification spam
  • Password reset abuse
  • IP-based and global attack patterns

🧾 Sessions & Persistence

  • Persistent sessions with “Remember Me”
  • 1-hour session without remember option
  • Up to 7 days with remember enabled
  • Automatic session refresh and rotation
  • Forced logout after sensitive actions (password/email change)

🧩 Authorization Ready

  • Role-based access control (RBAC)
  • Claim-based permissions
  • Clean separation between authentication and authorization

Zero-Config Setup

Getting started takes less than a minute:

npm install identityuser
npx identityuser
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The CLI copies a full authentication module into your project:

src/identityUser/
 ├── api/
 ├── components/
 ├── helper/
 ├── lib/
 ├── providers/
 ├── validation/
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No hidden magic.
No locked-in architecture.
Just clean, readable code you can own.


Who Is IdentityUser For?

IdentityUser is ideal if you:

  • Are building a serious Next.js product
  • Want full control over authentication logic
  • Care about security and long-term maintainability
  • Don’t want to depend entirely on third-party auth SaaS
  • Prefer explicit code over abstraction layers

Final Thoughts

Authentication is not where you want to experiment — but it’s also not where you want to lose control.

IdentityUser sits right in the middle:

  • Strong defaults
  • Real-world security
  • Full transparency

If you’re tired of reinventing authentication for every project, IdentityUser might be exactly what you’ve been looking for.

👉 GitHub: https://github.com/SadeghShojayefard/identityuser
👉 NPM: https://www.npmjs.com/package/identityuser
👉 Sample Project: https://github.com/SadeghShojayefard/identityusers_sample
👉 Full Documentation (PDF): https://github.com/SadeghShojayefard/identityusers_sample/blob/main/IdentityUser_Documentation.pdf

Top comments (6)

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hassan_rezaali_b64d94d40a profile image
Hassan Rezaali

From a developer experience perspective, this is refreshing. Many auth solutions optimize for “getting started fast” and completely ignore what happens six months later. Having explicit, readable code that new team members can inspect, debug, and reason about is a massive win. This feels especially valuable for growing teams working on serious Next.js products.

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hassan_rezaali_b64d94d40a profile image
Hassan Rezaali

What really stands out here is the architectural mindset behind IdentityUser. Treating authentication as first-class application code instead of an external black box makes a huge difference for long-term maintainability. Copying a complete, well-structured auth module into the project is a bold but very sensible approach for teams that actually want to understand and evolve their security layer over time.

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hassan_rezaali_b64d94d40a profile image
Hassan Rezaali

The real-world thinking behind features like fallback 2FA, forced logout after sensitive actions, and abuse protection is very apparent. These are the kinds of edge cases most tutorials skip, but they’re exactly what cause incidents in production. This reads like something built from experience with real users and real failures, not just a theoretical security checklist.

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mahdijazini profile image
Mahdi Jazini

Great write up. I really like the focus on full ownership and explicit auth logic instead of hiding everything behind abstractions or SaaS. The production oriented features like 2FA fallback rate limiting and session policies make this very appealing for serious Next.js applications. This feels much closer to how real world authentication should be built.

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hadil profile image
Hadil Ben Abdallah

This is a really solid write-up. I like how you position IdentityUser between “toy auth” and opaque SaaS solutions; that middle ground is exactly what many serious Next.js apps need.
The focus on ownership, security-first defaults, and explicit code over magic is refreshing, and the way 2FA, fallback flows, and session handling are thought through shows real production experience. Copying a complete, readable auth module into the project instead of hiding logic behind abstractions is a big win for maintainability and trust.
Great work 🔥

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sadegh_shojayefard profile image
Sadegh shojaye fard

If you’re using Next.js and care about long-term security and ownership, I’d love to hear your thoughts or feedback on IdentityUser.