Interview Simulation

System Design Interview Simulation

Practice architecture the way interviews actually run. Choose a scenario, place components and wire the data flow, then get structured feedback.

42 scenarios

Scenarios

42/42

#ScenarioDomainDifficulty

01
01Design a URL Shortening Service like Bitly
FreeBasic System Component · Easy
Basic System ComponentEasy
02
02Design a Task Management Application
FreeCollaborative System · Easy
Collaborative SystemEasy
03
03Design a Real-Time Notification System
FreeMessaging & Realtime · Medium
Messaging & RealtimeMedium
04
04Design a Rate Limiter
PremiumBasic System Component · Easy
Basic System ComponentEasy
05
05Design a Distributed Job Scheduler
PremiumScheduling Service · Medium
Scheduling ServiceMedium
06
06Design a Live Streaming Platform
PremiumDistributed Architecture · Hard
Distributed ArchitectureHard
07
07Design a File Storage Service like Dropbox
PremiumCollaborative System · Hard
Collaborative SystemHard
08
08Design a Load Balancer for Web Servers
PremiumBasic System Component · Easy
Basic System ComponentEasy
09
09Design a Distributed ID Generator
PremiumBasic System Component · Easy
Basic System ComponentEasy
10
10Design a Search Autocomplete System
PremiumProximity / Trie · Medium
Proximity / TrieMedium
11
11Design a Key-Value Store like Redis or DynamoDB
PremiumBasic System Component · Medium
Basic System ComponentMedium
12
12Design a Ride-Sharing Service like Uber or Lyft
PremiumProximity / Trie · Hard
Proximity / TrieHard
13
13Design a Pastebin
PremiumBasic System Component · Easy
Basic System ComponentEasy
14
14Design a Web Crawler
PremiumScheduling / Crawl · Medium
Scheduling / CrawlMedium
15
15Design a Chat / Messaging System like WhatsApp
PremiumMessaging & Realtime · Hard
Messaging & RealtimeHard
16
16Design a News Feed like Twitter or Facebook
PremiumSocial / Feed · Medium
Social / FeedMedium
17
17Design a Video-on-Demand Platform like YouTube or Netflix
PremiumDistributed Architecture · Hard
Distributed ArchitectureHard
18
18Design a Gaming Leaderboard
PremiumBasic System Component · Easy
Basic System ComponentEasy
19
19Design an Email / Notification Delivery Service
PremiumMessaging & Async · Medium
Messaging & AsyncMedium
20
20Design a Ticket Booking System like Ticketmaster
PremiumE-Commerce / Inventory · Medium
E-Commerce / InventoryMedium
21
21Design a Photo Sharing App like Instagram
PremiumSocial / Media · Hard
Social / MediaHard
22
22Design a Collaborative Document Editor like Google Docs
PremiumCollaborative System · Hard
Collaborative SystemHard
23
23Design a Content Delivery Network (CDN)
PremiumBasic System Component · Easy
Basic System ComponentEasy
24
24Design a Proximity Service like Yelp or Nearby Places
PremiumProximity / Location · Medium
Proximity / LocationMedium
25
25Design a Distributed Logging System
PremiumObservability · Medium
ObservabilityMedium
26
26Design a Payment System
PremiumFintech · Hard
FintechHard
27
27Design an Online Auction System like eBay
PremiumE-Commerce / Realtime · Hard
E-Commerce / RealtimeHard
28
28Design a Distributed Session Store
PremiumBasic System Component · Easy
Basic System ComponentEasy
29
29Design a Reliable Webhook Delivery System
PremiumMessaging & Async · Medium
Messaging & AsyncMedium
30
30Design a Metrics / Monitoring System
PremiumObservability · Medium
ObservabilityMedium
31
31Design a Food Delivery Service like DoorDash or Uber Eats
PremiumProximity / Marketplace · Hard
Proximity / MarketplaceHard
32
32Design a Music Streaming Service like Spotify
PremiumDistributed Architecture · Hard
Distributed ArchitectureHard
33
33Design a Distributed Lock Service
PremiumBasic System Component · Easy
Basic System ComponentEasy
34
34Design a Hotel Booking System like Booking.com
PremiumE-Commerce / Inventory · Medium
E-Commerce / InventoryMedium
35
35Design an Ad Click Aggregator
PremiumAnalytics / Ads · Medium
Analytics / AdsMedium
36
36Design a Recommendation System
PremiumML / Personalization · Medium
ML / PersonalizationMedium
37
37Design a Video Conferencing System like Zoom
PremiumMessaging & Realtime · Hard
Messaging & RealtimeHard
38
38Design a DNS System
PremiumBasic System Component · Easy
Basic System ComponentEasy
39
39Design a Calendar System like Google Calendar
PremiumCollaborative System · Medium
Collaborative SystemMedium
40
40Design an Online Judge like LeetCode
PremiumScheduling / Compute · Medium
Scheduling / ComputeMedium
41
41Design an E-Commerce Platform like Amazon
PremiumE-Commerce · Hard
E-CommerceHard
42
42Design a Short-Video Platform like TikTok
PremiumSocial / Media · Hard
Social / MediaHard