I Built an Authentication System With Express.js, MongoDB, (Access/Refresh Tokens, Sessions, Rate Limiting & More)

I recently finished building one of my most solid backend projects — a complete authentication system written in Express.js, powered by MongoDB, JWT, and a clean architecture design. Here’s what I implemented step-by-step: **🔐 Access + Refresh tokens with secure storage 🗂️ Session tracking in the database 🧹 Automatic session invalidation 🛡️ IP-based rate limiting (5 attempts / 10 mins) 🧪 Validation middleware for all inputs ⚠️ Global ApiError system for consistent error formatting 🧱 Clean architecture with controllers, services, utils 🛠️ Multiple bug fixes + edge case handling 🚀 Focus on maintainability & production readiness** This project taught me a LOT about system design, real-world auth, and secure backend development. If you like it, Hit a ⭐ on GitHub or share it with other developers! 👉 GitHub Repo: https://github.com/hamidukarimi/authforge-express If you have ideas on improvements or want the front-end version too — let me know!