5 real Distributed Systems interview questions asked at Apple. Upvoted by engineers who cleared the loop. Covers System Design rounds.
Apple
Hard
System Design round
Distributed SystemsAWSKafka
Design iCloud Photo Library — 2 billion photos synced across iPhone, iPad, and Mac.
Cover: deduplication (perceptual hashing), delta sync (only changed chunks), offline-first with conflict resolution, and privacy — how Apple performs server-side processing without seeing unencrypted photos.
↑ 59 upvotes · 57 engineers asked this · SDE2
Apple
Hard
System Design round
Distributed SystemsiOS
Design Apple Pay's tap-to-pay system. When a user taps their iPhone, a payment must complete in under 500ms even with no internet connection. Cover: secure element, tokenisation, NFC protocol, and offline authorisation.
↑ 59 upvotes · 38 engineers asked this · SDE2
Apple
Hard
System Design round
Distributed SystemsiOS
Design Siri's speech recognition pipeline. Audio is captured on-device, processed, and a response is returned. How do you split on-device vs server processing to balance latency, privacy, and accuracy?
↑ 53 upvotes · 32 engineers asked this · SDE2
Apple
Hard
System Design round
4-8 yearsSystem DesignDistributed Systems
Design an offline-first note-taking app that syncs across a phone, tablet, and laptop, resolving conflicts when the same note was edited on two devices while offline.
↑ 37 upvotes · 14 engineers asked this · Senior SDE
Apple
Hard
System Design round
4-8 yearsDistributed Systems
Two data centers each think they're the primary for a user's data after a network partition heals — a classic split-brain. How would you design the system to detect and resolve this safely?
↑ 21 upvotes · 9 engineers asked this · Senior SDE
Design iCloud Photo Library — 2 billion photos synced across iPhone, iPad, and Mac.
Design iCloud Photo Library — 2 billion photos synced across iPhone, iPad, and Mac.
Cover: deduplication (perceptual hashing), delta sync (only changed chunks), offline-first with conflict resolution, and privacy — how Apple performs server-side processing without seeing unencrypted photos.
Design Apple Pay's tap-to-pay system. When a user taps their iPhone, a payment must complete in under 500ms even with no internet connection. Cover: secure element, tokenisation, NFC protocol, and offline authorisation.
Design Apple Pay's tap-to-pay system. When a user taps their iPhone, a payment must complete in under 500ms even with no internet connection. Cover: secure element, tokenisation, NFC protocol, and offline authorisation.
Design Siri's speech recognition pipeline. Audio is captured on-device, processed, and a response is returned. How do you split on-device vs server processing to balance latency, privacy, and accuracy?
Design Siri's speech recognition pipeline. Audio is captured on-device, processed, and a response is returned. How do you split on-device vs server processing to balance latency, privacy, and accuracy?
Design an offline-first note-taking app that syncs across a phone, tablet, and laptop, resolving conflicts when the same note was edited on two devices while offline.
Design an offline-first note-taking app that syncs across a phone, tablet, and laptop, resolving conflicts when the same note was edited on two devices while offline.
Two data centers each think they're the primary for a user's data after a network partition heals — a classic split-brain. How would you design the system to detect and resolve this safely?
Two data centers each think they're the primary for a user's data after a network partition heals — a classic split-brain. How would you design the system to detect and resolve this safely?