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🏗️L4 · 7 modules · 101 lessons

System Design for Python Juniors

What FAANG-tier interviews actually ask

100 lessons across 6 modules: fundamentals (Big-O, capacity math), scalability & caching, databases & storage, messaging & microservices, and real-world case studies (Twitter feed, Netflix, Uber dispatch, Stripe webhooks, Calendly race conditions).

Browse all 101 lessons →Try the first lesson — no signup
101
lessons
7
modules
2
capstone missions
18
languages
What you'll learn

From day one

  • ✓Big-O capacity math: QPS, storage, growth projections
  • ✓Caching layers, CDN, eventual consistency
  • ✓Database partitioning, sharding, replication
  • ✓Message brokers: Kafka log-as-source vs Redis Pub/Sub
  • ✓Real case studies: URL shortener, Twitter timeline, Netflix CDN
  • ✓Uber dispatch, Stripe webhooks, Calendly scheduling races
  • ✓DNS anycast, DDoS scrubbing, log sampling tradeoffs
  • ✓Capstone: complete system design under realistic constraints
Curriculum

7 modules · 101 interactive lessons

#1Module 0 · Before you start
#2Module 1 · System Design Fundamentals
#3Module 2 · Scalability & Caching
#4Module 3 · Databases & Storage
#5Module 4 · Messaging, Streaming, Microservices
#6Module 5 · Real-World Case Studies
#7Module 6 · Real-World System Design Cases
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Frequently asked

Is this track too advanced for a junior?

No — modules 1-3 are 'system design lite' that juniors actually get asked. Modules 4-6 are FAANG-tier for mid+ candidates. Start where you're applying.

Does it use real case studies?

Yes — Twitter feed, Netflix recommendations, Uber dispatch, Stripe webhooks, Calendly race conditions. Each module ends with one full case study.

Will I be able to whiteboard a system design after this?

Yes. The track teaches the talking script + the trade-off vocabulary. Practice in the Interview Prep track and you can whiteboard most junior+ questions.

Does it cover databases in depth?

Module 3 covers Postgres / Redis / Cassandra / DynamoDB — when to pick which. Plus sharding, replication, indexing, the index-only-scan tricks senior interviews probe for.

What about distributed systems theory?

CAP, PACELC, consensus (Raft / Paxos at a high level), idempotency keys, exactly-once vs at-least-once. Enough to talk credibly; not a Lamport-paper deep-dive.

First 15 lessons free, no signup

All 101 lessons unlock for $12/month or $89/year. 7-day free trial — card required, cancel in 1 click anytime in Settings.

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