Interview questions
Find a company or topic. Read the sources, then practice.
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Find a company or topic. Read the sources, then practice.
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Showing 1,476–1,500
Reliable human notification: schedule resolution, durable escalation deadlines, acknowledgement races, and uncertain provider delivery.
Companies: Uber
durable-timers · fault-tolerance · idempotency · notification-delivery
Concurrent bids and fixed deadlines test price order, winner selection, and service behavior after failures.
General practice
concurrency · deadlines · hot-keys · idempotency
Financial views over an existing core, with strict account access, stable transaction history, and durable card controls.
General practice
account-access · audit · card-controls · core-banking-integration
Timed exams with simultaneous starts, durable answer saves, strict deadlines, and reliable submissions and grades.
General practice
burst-traffic · concurrency · deadline-enforcement · durability
Course launches stress enrollment, while course changes and repeated requests test progress correctness.
General practice
course-changes · enrollment · lesson-delivery · progress-correctness
Presence across devices: sudden disconnects, large viewer audiences, and status freshness during partial failures.
General practice
disconnect-detection · failure-recovery · large-viewer-audiences · multi-device-state
Telemetry delivery with bounded resources, trace sample decisions, tenant limits, and independent destination failures.
General practice
backpressure · delivery-semantics · fan-out · multi-tenancy
Order progress across services: repeated requests, delayed results, stock expiry, partial failures, and cancellation races.
General practice
atomic-order-updates · cancellation · order-lifecycle-correctness · progress-across-services
Shared feed updates and per-user unread state must meet freshness goals despite source limits, duplicate items, and popular feeds.
General practice
item-identity · popular-feeds · source-limits · unread-state
An SMS platform must control carrier load, track uncertain delivery, and charge each tenant correctly.
General practice
carrier-integration · delivery-status · multi-tenancy · rate-limits
Regional probe results can disagree, so the service must distinguish target outages from probe location failures.
General practice
duplicate-execution · history-retention · incident-alerts · probe-schedules
Swarm-based distribution: finding reachable peers, keeping rare pieces available, verifying untrusted data, and making peer upload capacity useful.
Companies: Atlassian, Google, Twitch
bandwidth-management · content-addressing · data-integrity · nat-traversal
Shared playback progress: backward seeks, delayed updates, offline conflicts, and reliable resume across devices.
General practice
concurrent-playback · conflict-resolution · consistency · idempotency
Hot-post counting: correct like/unlike state, replay-safe aggregation, burst capacity, and live updates to millions of viewers.
Companies: Amazon, Coinbase, Meta, Twitter
eventual-consistency · hot-keys · idempotency · real-time-fanout
Search over billions of posts: distributed keyword retrieval, fresh indexes, and permission checks that remain correct when visibility changes.
General practice
access-control · change-data-capture · distributed-search · inverted-index
GIF search and global media delivery: upload safety, search freshness, popular GIFs, and removal from embeds.
General practice
content-moderation · global-media-delivery · hot-keys · media-processing
High-volume event collection with retry-safe counting, late-arriving session data, distinct-user queries, and tenant skew.
Companies: Google, Meta, Microsoft, Qualtrics
approximate-counting · event-ingestion · event-time · multi-tenancy
Durable responses during viral traffic, safe retries, revision deadlines, and result totals with clear freshness.
General practice
capacity-limits · durability · form-revisions · result-accuracy-and-delay
Public image delivery: safe uploads, public albums, viral traffic, bandwidth cost, and image removal.
General practice
abuse-prevention · content-delivery · image-durability · read-scalability
Video playback across devices: format compatibility, quality changes, peak traffic, and time-bound access to licensed titles.
General practice
content-rights · peak-delivery-traffic · playback-under-changing-network-conditions · source-preparation-and-device-compatibility
Account-wide admission control: atomic slot allocation, expiring playback leases, and preventing regional failures from creating extra streams.
General practice
authorization · concurrency-control · fencing · idempotency
A device must resume media transfers, protect local storage, and enforce playback deadlines without a reliable connection.
General practice
content-expiration · drm · local-storage · mobile-background-tasks
A visual bookmark service must deliver images efficiently, preserve board access rules, and find related pins across billions of images.
General practice
access-control · caching · image-processing · object-storage
A question-and-answer platform with personal discovery, correct vote state, and answer order that reflects quality.
General practice
answer-quality · feed-discovery · freshness-and-visibility · search
A discussion platform with changing vote totals, community post ranks, popular communities, and large comment trees.
General practice
caching · concurrency · data-modeling · event-processing