40 skills · 487 questions · 5 min/day
Stop reading.Start building.
Your daily rep for system design. Practice the real interview problems instead of passively reading.
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Modeled on the real system-design problems engineers get asked at top tech companies. They're the same canonical questions behind the most-studied open-source prep guides.
- Rate Limiter
- URL Shortener
- News Feed
- Chat System
- Key-Value Store
- Web Crawler
- +6 more drills
487practice questions
40skills to master
12full design drillsEverything you need. Nothing you don't.
Questions, not lectures
Every skill is a series of MCQs, trade-off decisions, and bottleneck hunts. You learn by doing, not by watching.
5 minutes a day
Bite-sized lessons that fit your commute. Build a daily streak and watch your intuition compound over weeks.
Full design drills
12 famous system design problems like the rate limiter, URL shortener, and Twitter feed, all scored like a real interview.
How it works
- 01
Pick a skill
Choose from 40 skills across 5 tiers, from latency basics to distributed consensus.
- 02
Answer, don't memorize
Work through questions that force you to reason through trade-offs, not regurgitate definitions.
- 03
Build real fluency
Earn crowns, unlock drills, and walk into your interview with genuine design intuition.
The whole path, start to interview
40 skills across 6 tiers — from latency basics to distributed consensus — then 12 full design drills scored like a real interview.
- What Is System DesignFree
- Performance vs ScalabilityFree
- Latency, Throughput & BandwidthFree
- Latency Numbers to KnowFree
- Vertical vs Horizontal Scaling
- Back-of-the-Envelope Estimation
- The Request Lifecycle
- DNS
- HTTP & HTTPS
- TCP vs UDP
- Proxy vs Reverse Proxy
- CDNs
- Relational Databases & ACID
- SQL vs NoSQL
- Database Indexing
- Denormalization
- Replication
- Sharding & Partitioning
- Wide-Column Stores
- Load Balancing
- Caching Strategies
- Consistent Hashing
- CAP Theorem & PACELC
- Consistency Models & Quorums
- Availability & Fault Tolerance
- Typeahead & Trie Indexing
- Geospatial Indexing
- Message Queues
- Pub/Sub & Change Data Capture
- Fan-out Patterns
- REST vs GraphQL vs RPC
- API Gateways & Real-Time
- Idempotency & Rate Limiting
- Pagination
- Monoliths vs Microservices
- Service Discovery & Heartbeats
- Leader Election
- Sagas & Distributed Transactions
- Observability
- Security Basics
- Design a URL Shortener (TinyURL / Bit.ly)
- Design a Rate Limiter
- Design a Notification Service
- Design a News Feed (Twitter/Instagram timeline)
- Design a Chat System (WhatsApp / Messenger)
- Design a Web Crawler (search-engine spider)
- Design a Distributed Key-Value Store (Dynamo-style)
- Design Ride-Share Matching (Uber/Lyft)
- Design YouTube (Video Streaming Service)
- Design Dropbox (Cloud File Storage & Sync)
- Design Yelp (Proximity Search Service)
- Design Ticketmaster (Seat Reservation System)
Why I built Daily Scaffold
“AI writes most of our code now, and in the process many developers are quietly losing the ability to actually reason about a system. But architecture still has to be designed by humans, not generated by a model. I built Daily Scaffold to keep that skill sharp: a Duolingo for system design that helps developers build real architectural intuition, five minutes at a time, whether you're leveling up day to day or prepping for a technical interview.”
Frequently asked questions
- What is Daily Scaffold?
- Daily Scaffold is a gamified, practice-first app for learning system design. Instead of passive lectures, you answer questions and work through real design drills to build genuine architectural intuition, five minutes a day.
- Is Daily Scaffold good for system design interview prep?
- Yes. It covers 40 skills and 12 famous design drills modeled on the problems engineers are actually asked in interviews at top tech companies, such as designing a rate limiter, URL shortener, and news feed.
- How long does it take to prepare for a system design interview?
- You can make steady progress in five minutes a day. Daily Scaffold breaks system design into 40 skills across 6 tiers, so a few weeks of consistent daily practice builds the intuition interviews test — without marathon cramming sessions.
- Which system design questions does Daily Scaffold cover?
- It covers the questions engineers are most commonly asked through 12 full design drills — such as designing a rate limiter, URL shortener, news feed, chat system, web crawler, and a YouTube-scale video platform — plus 487 focused questions on the underlying concepts.
- Do I need a computer science degree to learn system design?
- No. Daily Scaffold starts from first principles — what latency, throughput, and scalability actually mean — and builds up to distributed systems, so you can learn system design whether or not you have a formal computer science background.
- Is Daily Scaffold free?
- The first two tiers (Foundations and Building Blocks) are free with no credit card required. A Pro subscription unlocks all 40 skills and 12 design drills.
Your next interview is waiting.
Start free — no credit card, no commitment. Just better system design thinking, 5 minutes at a time.
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