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Software Engineer Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
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Showing 1291–1320 of 2336 results
- MetaMediumSoftware EngineerDesign Real-Time Auctions for Social Posts
This question evaluates skills in designing scalable, low-latency real-time systems, including distributed architecture, concurrency control and ordering, data modeling, API design, and fault-tolerance for high-contention auction workloads.
System DesignOnsite - MetaHardSoftware EngineerDesign Ride Requests, Driver Matching, and Trip State
Design a high-scale real-time ride-hailing dispatch and trip lifecycle backend. The problem tests geospatial indexing, high-throughput location ingestion, concurrent driver assignment without double-booking, and idempotent distributed state management.
System DesignOnsiteDistributed SystemsGeospatialConcurrency - MetaMediumSoftware EngineerDesign a Code Review Agent
This question evaluates a candidate's ability to design ML-powered developer tooling, covering competencies in LLM orchestration, deterministic tool integration, repository context management, code-analysis heuristics, safety and validation strategies, and inference cost estimation.
ML System DesignOnsite - MetaHardSoftware EngineerDesign a Dropbox-like file storage and sync service
Design a Dropbox-like file storage and sync service evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnsite - MetaMediumSoftware EngineerDesign a Messenger-Style Chat Backend Without WebSockets or Persistent Connections
Design a Messenger-style chat backend for one-to-one conversations without WebSockets or other persistent connections, using only request/response web APIs. Tests message ordering, idempotent sends, cursor-based sync, cheap polling, push wake-ups, multi-device delivery and failure handling at very large scale.
System DesignOnsite - MetaMediumSoftware EngineerDesign a Notification System That Delivers Events to Users at Scale
A system design question on a notification platform that takes events from many product services and delivers them to users through push and in-app channels. It tests ingestion contracts, preference checks, grouping and rate limiting, priority isolation, third-party push delivery, and deduplication under retries.
System DesignOnsite - MetaMediumSoftware EngineerDesign a People-You-May-Know Friend Recommendation System
A system design question on recommending people a user may know on a large social network, from candidate generation through ranking and serving. It tests graph-based candidate sourcing, batch versus real-time freshness, ranking signals and labels, filtering, privacy, cold start, and evaluation.
System DesignOnsite - MetaMediumSoftware EngineerDesign a Ranked Home News Feed for a Large Social Network
A system design question on building the home news feed of a large social network: publishing posts and serving each user a ranked, paginated feed of posts from the accounts they follow. It tests fan-out strategy, accounts with huge follower counts, ranking under a latency budget, and correctness for deletes and privacy.
System DesignOnsite - MetaMediumSoftware EngineerDesign a Real-Time Chat Service for One-to-One and Group Messaging
A system design question on a real-time chat service with one-to-one and group conversations, instant delivery to online users, offline catch-up, and history across devices. It tests connection routing, per-conversation ordering, idempotent sends, message storage, group fan-out, and read receipts.
System DesignOnsite - MetaMediumSoftware EngineerDesign a Real-Time Trending Hashtags System
This question evaluates a candidate's ability to design a large-scale, real-time data processing system that continuously scores and ranks trending content under strict freshness constraints. It tests system design skills including stream processing, time-decayed scoring, and handling high write throughput at scale. This type of question is commonly used to assess architectural thinking for systems balancing timeliness, popularity, and novelty signals.
System DesignOnsite - MetaMediumSoftware EngineerDesign a Reliable Notification System
Design an enterprise-scale notification platform supporting multi-channel delivery, recipient fanout, preference filtering, and resilient at-least-once delivery guarantees.
System DesignOnsiteDistributed SystemsMessage QueuesScalability - MetaMediumSoftware EngineerDesign a Top-K trending items service
This question tests the ability to design a high-throughput, distributed system that maintains a real-time ranking of the most popular items across a massive global user base.
System DesignOnsiteDistributed SystemsData StreamsCaching - MetaMediumSoftware EngineerDesign a YouTube/Netflix video platform
This question evaluates a candidate's understanding of distributed systems architecture, media processing and delivery concepts including upload resiliency, transcoding into multiple bitrates, scalable storage and low-latency streaming.
System DesignOnsite - MetaHardSoftware EngineerDesign a content processing service
This question evaluates understanding of designing scalable, reliable content-processing systems that handle high-throughput ingestion, ML-based classification and rule evaluation, priority/backpressure mechanisms, storage and API design, experimentation hooks, and operational concerns like observability and cost.
System DesignOnsite - MetaMediumSoftware EngineerDesign a flight search platform
This question tests the ability to design a high-scale search platform that aggregates volatile data from heterogeneous third-party providers while maintaining low latency and high availability.
System DesignOnsiteDistributed SystemsAPI DesignCaching - MetaMediumSoftware EngineerDesign a game leaderboard service
This question tests the ability to design a high-throughput, low-latency leaderboard system, focusing on data structures for ranking, storage trade-offs, and scalability under heavy write and read loads.
System DesignOnsiteScalabilityData StructuresCaching - MetaMediumSoftware EngineerDesign a large-scale web crawler
This question evaluates a candidate's ability to design scalable, fault-tolerant distributed systems for web-scale data acquisition, covering competencies such as crawler architecture, URL frontier management, deduplication, per-domain rate limiting and robots.
System DesignOnsite - MetaMediumSoftware EngineerDesign a live video comments system
This problem tests your ability to design a high-throughput, real-time messaging system capable of handling sudden spikes in concurrent viewers and maintaining low latency for chat delivery.
System DesignOnsiteWebSocketsPub/SubScalability - MetaMediumSoftware EngineerDesign a marketplace price tracking service
This question evaluates a candidate's ability to design scalable, reliable ingestion and processing pipelines, time-series price storage and querying, deduplication across users, and notification/alert mechanisms for a large-scale price-tracking service.
System DesignOnsite - MetaMediumSoftware EngineerDesign a post privacy/visibility system
This question evaluates a candidate's ability to design access control and visibility mechanisms for social posts, covering privacy models, efficient read-time enforcement, data modeling, caching strategies, and handling dynamic friendship and privacy updates.
System DesignOnsite - MetaMediumSoftware EngineerDesign a price drop tracking service
This question evaluates system-design competencies such as scalable architecture, data modeling for time-series price history, external data ingestion and integration, alerting and monitoring, and trade-off reasoning for large-scale services.
System DesignOnsite - MetaHardSoftware EngineerDesign a product notifications system
This question evaluates system design competencies for building a large-scale notifications platform—covering architecture, APIs, data modeling, event pipelines, delivery semantics (retries, deduplication, idempotency), targeting/segmentation, localization, monitoring, and legal compliance such as GDPR/CCPA.
System DesignOnsite - MetaHardSoftware EngineerDesign a real-time messenger
A Meta software-engineer system-design onsite question: design a real-time messenger supporting 1:1 and group chats at 100M MAU with p99 send-to-receive latency under 150 ms. It covers APIs, message ordering and idempotency, delivery semantics, multi-device sync, WebSocket fanout, storage/search, E2EE, abuse controls, retention/GDPR, multi-region failover, and observability.
System DesignOnsite - MetaHardSoftware EngineerDesign a ticketing purchase system
This question evaluates understanding of large-scale system design and distributed systems concepts, including concurrency control, consistency models, real-time fanout, payment idempotency, and failure handling for high-concurrency ticketing with interactive seat maps.
System DesignOnsite - MetaMediumSoftware EngineerDesign ad click tracking and dashboard at scale
This problem tests your ability to design a high-throughput, fault-tolerant ingestion pipeline and an aggregation service for real-time analytics dashboarding.
System DesignOnsiteDistributed SystemsData PipelinesScalability - MetaMediumSoftware EngineerDesign an Expected O(1) Randomized Container
Design a distinct-element container with expected constant-time insertion and uniformly random removal. The discussion covers mutation invariants, uniformity, empty-state behavior, expected complexity, deterministic randomness tests, and how duplicate or concurrent variants would change the contract.
Software Engineering FundamentalsOnsite - MetaHardSoftware EngineerDesign an Instagram-like photo-sharing platform
This question evaluates system design competencies including distributed systems, scalability and capacity planning, data modeling and storage strategies, API design, media processing and CDN integration, consistency models, operational reliability, observability, and estimation.
System DesignOnsite - MetaMediumSoftware EngineerDesign an On-Demand Delivery Platform
This question evaluates skills in designing scalable, reliable distributed systems with emphasis on state management (shopping cart persistence), real-time telemetry (courier location updates), workflow orchestration (order lifecycle and dispatch), and operational concerns like scalability and reliability.
System DesignOnsite - MetaHardSoftware EngineerDesign an ad click tracking system
This problem tests your ability to design a high-scale, fault-tolerant distributed system capable of processing massive volumes of real-time ad click events while ensuring data consistency and accuracy.
System DesignOnsiteDistributed SystemsHigh-throughputData Engineering - MetaMediumSoftware EngineerDesign an online auction system
A Meta software engineer onsite system design question: build an eBay-style online auction platform supporting proxy bidding, reserve prices, buy-it-now and soft close at 500k concurrent auctions and 5M watchers with p99 bid-to-UI latency under 200 ms. The answer covers APIs, data model, the proxy-bid pricing algorithm, single-writer-per-auction consistency, idempotent bid placement, real-time push trade-offs (polling vs long polling vs SSE vs WebSockets), sharding, finalization and recovery. It also covers anti-sniping, fraud, escrow payments, auditability and capacity estimation.
System DesignOnsite
Meta