Why Rate Limiting Matters?

APIs power the web, but without rate limiting, a single user (or bot) can overload your system. Think about how login attempts, API calls, and DDOS attacks could take down your app.

Let’s see if you can design a rate-limiting system like the pros!


🛡️ Challenge #1: Implement Basic Rate Limiting

The Problem

Your API is getting too many requests from a single user. You need to limit how often they can hit an endpoint.

The Solution

1️⃣ Use a token bucket or fixed window algorithm to track requests.

2️⃣ Allow users X requests per minute (e.g., 100 requests/min).

3️⃣ Return 429 Too Many Requests when the limit is hit.

💡 Bonus Challenge: Implement different rate limits for free and premium users.


🔄 Challenge #2: Scaling Rate Limiting with Redis

The Problem

Your rate-limiting logic fails at scale—you need to distribute it across multiple servers.

The Solution

1️⃣ Store request counts in Redis (fast & scalable).

2️⃣ Sync rate limits across all API servers in real-time.

3️⃣ Implement IP-based & user-based rate limits for more security.

💡 Bonus Challenge: Implement Geo-based rate limiting (e.g., limit per region).


Final Thoughts

Rate limiting isn’t just about stopping spam—it’s about:

Preventing abuse & DDOS attacks

Scaling APIs without crashes

Fair usage between free & premium users

🚀 Want more challenges like this? Start learning here 👉 Backend Challenges