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70 questionsPick one to begin

1. 01
   Design BitlyStorage, files and links
   Mid-level · SeniorGoogle · Amazon
   Practise
2. 02
   Disagree with a teammateCollaboration
   Any levelGeneral practice
   Practise
3. 03
   Design a rate limiterInfrastructure and platform
   Mid-level · SeniorMicrosoft · Google
   Practise
4. 04
   Learn from a failureLearning from failure
   Any levelGeneral practice
   Practise
5. 05
   Design an A/B testing platformInfrastructure and platform
   Senior · StaffAffirm · Airbnb
   Practise
6. 06
   Design an ad click aggregatorInfrastructure and platform
   SeniorMeta
   Practise
7. 07
   Design an ad serving systemInfrastructure and platform
   Senior · StaffNetflix · Amazon
   Practise
8. 08
   Design Amazon LockersShopping, tickets and booking
   Mid-levelAmazon
   Practise
9. 09
   Design ChatGPTAI systems
   Senior · StaffOpenAI · Anthropic
   Practise
10. 10
    Design GitHub ActionsInfrastructure and platform
    Senior · StaffOpenAI · Google
    Practise
11. 11
    Design a cloud IDECollaboration
    Senior · StaffOpenAI
    Practise
12. 12
    Design a digital walletPayments and ledgers
    StaffGeneral practice
    Practise
13. 13
    Design a distributed cacheInfrastructure and platform
    SeniorGoogle
    Practise
14. 14
    Design a distributed denylistSearch and autocomplete
    SeniorGoogle · LinkedIn
    Practise
15. 15
    Design a distributed key-value storeInfrastructure and platform
    Senior · StaffAnthropic
    Practise
16. 16
    Design a distributed message queueInfrastructure and platform
    StaffAmazon
    Practise
17. 17
    Design DropboxStorage, files and links
    Mid-level · SeniorGoogle · Meta
    Practise
18. 18
    Design Facebook post searchSocial feed and timeline
    Senior · StaffGeneral practice
    Practise
19. 19
    Design a flash saleShopping, tickets and booking
    Senior · StaffDisney
    Practise
20. 20
    Design real-time fraud detectionPayments and ledgers
    Senior · StaffPayPal · Stripe
    Practise
21. 21
    Design a game leaderboardInfrastructure and platform
    Mid-level · SeniorMeta
    Practise
22. 22
    Design Google CalendarCollaboration
    Mid-level · SeniorGoogle · LinkedIn
    Practise
23. 23
    Design Google DocsCollaboration
    StaffAmazon · Meta
    Practise
24. 24
    Design Google MapsMaps and location
    StaffGeneral practice
    Practise
25. 25
    Design a hotel booking systemShopping, tickets and booking
    Mid-level · SeniorAirbnb
    Practise
26. 26
    Design InstagramSocial feed and timeline
    Mid-level · SeniorMeta
    Practise
27. 27
    Design a job schedulerInfrastructure and platform
    SeniorOpenAI · Google
    Practise
28. 28
    Design LeetCodeCollaboration
    Mid-level · SeniorMeta
    Practise
29. 29
    Design Facebook Live commentsSocial feed and timeline
    SeniorMeta
    Practise
30. 30
    Design TwitchStreaming and media
    SeniorUber
    Practise
31. 31
    Design an LLM gatewayAI systems
    Senior · StaffGitHub · Moveworks
    Practise
32. 32
    Design an LLM inference batching serviceAI systems
    SeniorAnthropic
    Practise
33. 33
    Design a local delivery serviceMaps and location
    Mid-levelMeta · Deliveroo
    Practise
34. 34
    Design login and authenticationInfrastructure and platform
    Mid-level · SeniorStripe · Visa
    Practise
35. 35
    Design a metrics monitoring systemInfrastructure and platform
    Senior · StaffGoogle · OpenAI
    Practise
36. 36
    Design nearby friendsMaps and location
    SeniorGeneral practice
    Practise
37. 37
    Design the Facebook news feedSocial feed and timeline
    Mid-level · SeniorMeta
    Practise
38. 38
    Design a notification systemMessaging and notifications
    Mid-level · SeniorAmazon
    Practise
39. 39
    Design an online auctionShopping, tickets and booking
    SeniorMeta
    Practise
40. 40
    Design online chessCollaboration
    Mid-level · SeniorMeta · OpenAI
    Practise
41. 41
    Design an over-the-air update systemInfrastructure and platform
    Mid-level · SeniorTesla · Microsoft
    Practise
42. 42
    Design peer-to-peer file distributionInfrastructure and platform
    Senior · StaffAnthropic · Google
    Practise
43. 43
    Design PastebinStorage, files and links
    Mid-levelBojaleLabs
    Practise
44. 44
    Design a payment systemPayments and ledgers
    Senior · StaffStripe · OpenAI
    Practise
45. 45
    Design a permission systemCollaboration
    Senior · StaffAtlassian · Notion
    Practise
46. 46
    Design photo storage with dedupStorage, files and links
    SeniorOpenAI
    Practise
47. 47
    Design presence and live cursorsCollaboration
    Mid-level · SeniorMicrosoft · Figma
    Practise
48. 48
    Design a price drop trackerShopping, tickets and booking
    Mid-levelMeta
    Practise
49. 49
    Design RAG for company documentsAI systems
    SeniorMeta · Microsoft
    Practise
50. 50
    Design a recommendation systemAI systems
    SeniorNetflix · Meta
    Practise
51. 51
    Design S3 object storageStorage, files and links
    StaffMeta
    Practise
52. 52
    Design search autocompleteSearch and autocomplete
    Mid-level · SeniorMeta · Google
    Practise
53. 53
    Design Snapchat messagingMessaging and notifications
    SeniorGeneral practice
    Practise
54. 54
    Design RobinhoodPayments and ledgers
    Senior · StaffRobinhood
    Practise
55. 55
    Design a text-to-video serviceAI systems
    SeniorOpenAI
    Practise
56. 56
    Design TicketmasterShopping, tickets and booking
    Mid-level · Senior · StaffMeta · Google
    Practise
57. 57
    Design a top songs widgetStreaming and media
    SeniorMeta
    Practise
58. 58
    Design UberMaps and location
    SeniorAmazon · Meta
    Practise
59. 59
    Design a unique ID generatorInfrastructure and platform
    Mid-levelGeneral practice
    Practise
60. 60
    Design a web crawlerSearch and autocomplete
    SeniorMeta · Anthropic
    Practise
61. 61
    Design a webhook delivery systemInfrastructure and platform
    Mid-level · SeniorOpenAI · Snowflake
    Practise
62. 62
    Design WhatsAppMessaging and notifications
    Mid-level · Senior · StaffMeta · Amazon
    Practise
63. 63
    Design YelpMaps and location
    Mid-levelYelp · Uber
    Practise
64. 64
    Design YouTubeStreaming and media
    Mid-level · SeniorAmazon · Google
    Practise
65. 65
    Lead without authorityInfluence
    Any levelGeneral practice
    Practise
66. 66
    Take ownership of a problemOwnership
    Any levelGeneral practice
    Practise
67. 67
    Make progress with unclear requirementsDealing with ambiguity
    Any levelGeneral practice
    Practise
68. 68
    Deliver under a tight deadlineDelivering results
    Any levelGeneral practice
    Practise
69. 69
    Act on difficult customer feedbackCustomer focus
    Any levelGeneral practice
    Practise
70. 70
    Make a difficult trade-offJudgement
    Any levelGeneral practice
    Practise