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 1,351–1,375
Companies: Netflix
Counter accuracy, client retries, and popular counters create tradeoffs between exact results, availability, and throughput.
General practice
consistency · distributed-counters · hot-keys · popular-counter-read-cost
Per-group leader authority under process pauses, network failures, and delayed writes from former leaders.
General practice
failure-detection · failure-recovery · leader-election · network-partitions
Durable work distribution: replicated queue state, visibility leases, duplicate delivery, poison messages, and hot-queue partitioning.
Companies: Amazon, Apple, Instacart
backpressure · dead-letter-queues · delivery-semantics · partitioning
SQL across storage systems: distributed joins, limited memory, uneven data, and shared worker capacity.
General practice
distributed-sql · distributing-data-and-work · memory-limits · overload-and-shared-capacity
SQL across servers: transaction order, regional failures, distributed query costs, and capacity changes during active transactions.
General practice
capacity-changes · data-distribution · query-execution · regional-failures
Write-heavy observability pipeline: context propagation, coherent sampling, partial traces, and indexed search without slowing application traffic.
Companies: Amazon, Uber
backpressure · causal-ordering · context-propagation · sampling
Atomic commits across stores: durable decisions, crash recovery, uncertain outcomes, and progress limits during partitions.
General practice
atomic-commit · coordinator-availability · crash-recovery · network-partitions
A high-throughput ID service with a fixed bit limit, clock faults, safe process restarts, and regional failures.
General practice
bit-allocation · clock-skew · coordination · fault-tolerance
Provider search and appointments across clinics, with stale calendars, concurrent requests, and uncertain appointment results.
General practice
calendar-freshness · clinic-integration · geospatial-search · provider-conflicts
Flexible documents with fresh secondary indexes, queries across shards, and durable writes during replica failures and data moves.
General practice
consistency · document-storage · query-planning · replication
A ledger must preserve accounting rules and account balances through concurrent transfers, repeated requests, and failures.
General practice
accounting-invariants · concurrency · durability · idempotency
Fast flag decisions with stable rollout groups, clear rule precedence, and continued service during configuration outages.
General practice
configuration-distribution · deterministic-rollouts · fault-tolerance · feature-flags
A fixed-stock giveaway under burst traffic: atomic claims, retry-safe allocation, admission control, and durable success.
Companies: Deliveroo, Google
admission-control · concurrency · durability · idempotency
Vehicle telemetry can arrive late, but assignments and maintenance rules must remain correct.
General practice
concurrent-operational-changes · duplicate-reports-and-command-retries · event-ordering · maintenance-schedules
Global aircraft data: late reports, conflicting sources, flight identity, and fast map updates.
General practice
data-quality · entity-resolution · event-time · geospatial-indexing
A directed account graph with reliable changes, account limits, large follower lists, and accurate follower counts.
General practice
account-limits · follower-count-accuracy · follower-lists · relationship-changes
Coordinating restaurant preparation, exclusive courier assignments, and live location updates across an asynchronous order lifecycle.
General practice
dispatch · geospatial-indexing · idempotency · order-state-machines
A marketplace combines profile search, job matches, exclusive job awards, and contract payments that must remain correct after retries.
General practice
concurrent-awards · job-matches · milestone-lifecycle · payments
Matches need compatible skills, acceptable latency, and complete parties. Short queue waits can conflict with these goals.
General practice
failure-recovery · matchmaking · party-constraints · player-ownership
Frequent score updates, exact global and regional ranks, stable ties, and consistent nearby results during failures.
General practice
consistency · query-load · rank-queries · recovery
Global address lookup: ambiguous text, international formats, nearby places, location precision, and source changes.
General practice
address-ambiguity · address-data-changes · coordinate-results · international-addresses
High location volume, overlapping fences, uncertain GPS fixes, and reliable enter and exit events.
General practice
device-state · event-delivery · event-order · geospatial-data
Large Git transfers, concurrent ref updates, durable objects, and safe object removal.
General practice
concurrency-control · data-transfer · durable-storage · garbage-collection