System Design Prep

Your daily FAANG-track study companion. Read the lesson, take the interactive quiz, get feedback in chat, revisit weak areas.

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Diagnostic Quiz

Interactive 10-question baseline. Auto-graded MCQ + T/F.

The full 30-day roadmap: Foundations → Case Studies.

Your scores, streak, weak areas, and revisit queue.

27 LeetCode patterns · 162 problems. Track solves in your browser.

14 low-level design problems. Cards link out to the GitHub write-up.

Lessons

Day 1 — Client-Server, HTTP/HTTPS, and DNS

Full explanation with FAANG interview angle.

Day 2 — Latency, Throughput, and "Numbers Every Engineer Should Know"

Full explanation with FAANG interview angle.

Day 3 — TCP vs UDP, WebSockets, Long Polling, SSE

Full explanation with FAANG interview angle.

Day 4 — Load Balancers Deep Dive

Full explanation with FAANG interview angle.

Day 5 — Caching Fundamentals

Full explanation with FAANG interview angle.

Day 6 — Cache Strategies Deep Dive

Full explanation with FAANG interview angle.

Day 7 — Content Delivery Networks (CDN) Deep Dive

Full explanation with FAANG interview angle.

Day 8 — SQL vs NoSQL — When to Pick Which

Full explanation with FAANG interview angle.

Day 9 — ACID vs BASE, Isolation Levels

Full explanation with FAANG interview angle.

Day 10 — Indexing: B-tree, LSM-tree, Hash, and Beyond

Full explanation with FAANG interview angle.

Day 11 — Replication: Leader-Follower, Multi-Leader, Leaderless

Full explanation with FAANG interview angle.

Quizzes

Day 1 Quiz — Client-Server, HTTP, DNS

Interactive: click, submit, get instant explanations.

Day 2 Quiz — Latency, Throughput & Numbers

Interactive: click, submit, get instant explanations.

Day 3 Quiz — TCP/UDP, WebSockets, Long Polling, SSE

Interactive: click, submit, get instant explanations.

Day 4 Quiz — Load Balancers (+ spaced-repetition callbacks)

Interactive: click, submit, get instant explanations.

Day 5 Quiz — Caching Fundamentals

Interactive: click, submit, get instant explanations.

Day 6 Quiz — Cache Strategies Deep Dive

Interactive: click, submit, get instant explanations.

Day 7 Quiz — Content Delivery Networks (CDN) Deep Dive

Interactive: click, submit, get instant explanations.

Day 8 Quiz — SQL vs NoSQL — When to Pick Which

Interactive: click, submit, get instant explanations.

Day 9 Quiz — ACID vs BASE, Isolation Levels

Interactive: click, submit, get instant explanations.

Day 10 Quiz — Indexing: B-tree, LSM, Hash, and Beyond

Interactive: click, submit, get instant explanations.

Day 11 Quiz — Replication: Leader-Follower, Multi-Leader, Leaderless

Interactive: click, submit, get instant explanations.

Diagnostic Quiz — Baseline Assessment

Interactive: click, submit, get instant explanations.

Reviews & Answers

Day 1 Review — Client-Server, HTTP, DNS — 2026-07-22

Per-question feedback and improvement notes.

Day 2 Review — Latency, Throughput & Numbers — 2026-07-22 (final)

Per-question feedback and improvement notes.

Day 3 Review — TCP/UDP, WebSockets, Long Polling, SSE — 2026-07-22

Per-question feedback and improvement notes.

Day 4 Review — Load Balancers — 2026-07-24

Per-question feedback and improvement notes.

Day 5 Review — Caching Fundamentals — 2026-07-26

Per-question feedback and improvement notes.

Day 6 Review — Cache Strategies Deep Dive — 2026-08-01

Per-question feedback and improvement notes.

Day 7 Review — Content Delivery Networks (CDN) Deep Dive — 2026-08-01

Per-question feedback and improvement notes.

Day 8 Review — SQL vs NoSQL — 2026-08-02

Per-question feedback and improvement notes.

Day 9 Review — ACID vs BASE, Isolation Levels — 2026-08-08

Per-question feedback and improvement notes.

Day 10 Review — Indexing: B-tree, LSM, Hash, and Beyond — 2026-08-08

Per-question feedback and improvement notes.

Built 2026-08-14 17:53. Regenerate: python3 build.py