System Design

Capstone journey

One app · 12 guided projects · Beginner to Expert

Build one real app and carry it all the way to production.

You take the same app (Linkly) through 12 projects, each one solving the pain the last left behind. By the end you have shipped a production-grade system, the kind of portfolio piece that gets interviews.

You start

Scope it and size it with real capacity math

You finish

Write the design doc and defend the tradeoffs

Beginner3Intermediate3Advanced4Expert2

12 projects · ~80.5h of building · free to preview

Beginner3 projects

Intermediate3 projects

Advanced4 projects

Expert2 projects

Capstone journey

Build one real app and carry it all the way to production.

Scope it and size it with real capacity math

Design its core: API, data model, and short codes

Scale its reads before they melt the database

Spread load across a stateless app tier

Replicate the database and split reads from writes

Shard the keyspace with consistent hashing

Protect it with rate limiting and abuse controls

Count clicks with an async analytics pipeline

Go global with edge caching and geo-routing

Make it correct under failure: consistency and idempotency

Survive a region loss with multi-region and DR

Write the design doc and defend the tradeoffs