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Phase 5 — Authentication & Authorization

Phase 5 — Authentication & Authorization

Section titled “Phase 5 — Authentication & Authorization”

Introduction

Section titled “Introduction”

This phase teaches authentication and authorization from first principles to production implementation in Next.js applications. Learners will understand how to build secure auth systems including email/password, JWT, sessions, OAuth, and role-based access control.

Why this module exists

Section titled “Why this module exists”

Authentication is critical for web applications. This module fills the gap between basic tutorials and production-ready implementations, covering security best practices, common pitfalls, and real-world patterns used by Auth.js, Clerk, Supabase, and Firebase.

Learning objectives

Section titled “Learning objectives”
  • Understand authentication vs authorization
  • Implement email/password login with secure password hashing
  • Use JWT and session-based authentication
  • Integrate OAuth providers (Google, GitHub)
  • Protect routes with middleware and role-based access control
  • Implement password reset, email verification, and magic links
  • Secure authentication against CSRF, XSS, and brute-force attacks
  • Build production auth architecture with refresh tokens and audit logs

Prerequisites

Section titled “Prerequisites”
  • Basic JavaScript and TypeScript knowledge
  • Familiarity with Next.js App Router
  • Understanding of HTTP cookies and headers
  • Basic database concepts (SQL or NoSQL)

Topics covered

Section titled “Topics covered”
  1. Authentication Basics
  2. Auth.js (Next.js) Integration
  3. Login/Registration Flows
  4. Authorization Patterns
  5. Security Best Practices
  6. Third-Party Auth Providers
  7. Production Authentication Architecture

Authentication roadmap

Section titled “Authentication roadmap”
Fundamentals → Core Implementation → Advanced Features → Security → Production

Real-world applications

Section titled “Real-world applications”
  • SaaS applications with multi-tenancy
  • E-commerce platforms with user accounts
  • Social media platforms with social login
  • Enterprise systems with RBAC and audit trails
  • Financial applications requiring MFA and session management

Estimated learning time

Section titled “Estimated learning time”

20-30 hours including exercises and mini projects

Practice exercises

Section titled “Practice exercises”
  • Build login/logout flow with Auth.js
  • Implement role-based dashboard access
  • Add Google OAuth login
  • Create password reset with email verification
  • Secure API routes with middleware

Mini project

Section titled “Mini project”

Build a full-stack Next.js application with:

  • Email/password authentication
  • JWT refresh token rotation
  • Google and GitHub OAuth
  • Role-based admin/user dashboards
  • Password reset and email verification
  • Protected API routes
  • Auth audit logging
Section titled “Related modules”
  • Phase 3: Rendering and Data Fetching (for protected data fetching)
  • Phase 4: State Management (for auth state in client components)
  • Phase 6: Testing and Deployment (for testing auth flows)