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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.
- 9403
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- 546
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- 11
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Showing 4951–4980 of 9403 results
- MetaMediumSoftware EngineerDesign a Concurrent, Memory-Bounded Tally Service
This problem tests the ability to design a high-throughput, memory-efficient data structure for time-series counting that balances concurrency, accuracy, and storage constraints.
Software Engineering FundamentalsTechnical ScreenConcurrencyTime-SeriesData-Structures - 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 GPS Fitness Tracking App with Activity Uploads and a Friends Feed
A system design interview question asking you to build a GPS fitness-tracking app in the style of Strava, where athletes record runs and rides, save routes and follow friends' activity feeds. It tests offline-tolerant recording, duplicate-free uploads, storage for large GPS tracks, feed fan-out and privacy controls.
System DesignOther - MetaMediumMachine Learning EngineerDesign a Large-Scale Personalized Recommendation System End to End
An ML system design question asking you to design a large-scale personalized recommendation system end to end, from candidate retrieval and multi-stage ranking to training data, evaluation, serving and monitoring. It tests problem framing, latency budgeting, cold start, feedback loops and online experimentation.
ML 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 - MetaMediumSecurity EngineerDesign a Real-Time Collaborative Coding Interview Pad, Then Threat-Model It
A two-phase security engineering design prompt from Meta: design a browser-based collaborative coding pad with real-time co-editing, code execution and session playback, then threat-model your own architecture. It tests concurrent editing, sandboxing untrusted code, access control, tenant isolation and risk prioritization.
System DesignOnsite - MetaMediumMachine Learning EngineerDesign a Real-Time Question-Answering Chatbot: Training Data, RL Tasks and Rewards
An AI design question about a chatbot that answers user questions in real time. It tests the low-latency serving and retrieval path, training data collection for fine-tuning and preference learning, reinforcement-learning task and reward design, and the ability to name reward weaknesses and mitigate them.
ML System DesignTechnical Screen - 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 - MetaHardData ScientistDesign a Restaurant Recommendation System for Food Apps
Meta machine learning system-design prompt on restaurant recommendations for food apps, covering retrieval and ranking models, features, cold start, implicit feedback, offline metrics, A/B testing, and marketplace guardrails.
Machine LearningOnsite - MetaMediumMachine Learning EngineerDesign a Short-Video Recommendation System
This question tests your ability to design a multi-stage recommendation pipeline for a high-traffic short-video platform, focusing on candidate retrieval, ranking models, and system scalability.
ML System DesignTechnical ScreenRecommendation SystemsScalabilityRanking - MetaEasySoftware EngineerDesign a String Calculator with Explicit Grammar and Evaluation Rules
This problem tests the ability to implement a parser for basic mathematical expressions, specifically focusing on handling operator precedence and parentheses using a stack-based approach.
Software Engineering FundamentalsTechnical ScreenStacksParsingAlgorithms - 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 - MetaEasySoftware EngineerDesign a Trade Ledger Class
This problem evaluates your ability to design a class interface that maintains an ordered collection of events and allows efficient retrieval based on time-based criteria.
Software Engineering FundamentalsTechnical ScreenData StructuresAPI DesignBinary Search - 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 - MetaMediumSoftware EngineerDesign a bank system with scheduled transfers
This question evaluates object-oriented design and stateful system skills, including time-ordered event processing, scheduling and cancellation semantics, balance accounting, and top-k aggregation using appropriate data structures.
Coding & AlgorithmsOnline Assessment - MetaHardSoftware EngineerDesign a bank system with scheduling and rankings
Design a bank system with scheduling and rankings 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 DesignTechnical Screen - MetaHardSoftware EngineerDesign a bank system with transfers
This question evaluates system-design and transactional engineering skills for financial services, including API design, data modeling, correctness under holds and transfer expirations, idempotency, merge semantics, and complexity reasoning.
System DesignHR Screen - MetaHardSoftware EngineerDesign a basic bank system API
This question evaluates a candidate's ability to design and implement an in-memory banking API, focusing on data modeling, API semantics, invariants (such as monotonic timestamps and non-negative balances), idempotency, and basic concurrency control.
System DesignOnline Assessment - MetaHardData ScientistDesign a clustered A/B test with spillovers
This question tests the ability to design a cluster-randomized experiment when interactions between users (network interference) violate the stable unit treatment value assumption (SUTVA).
Analytics & ExperimentationHR ScreenCausal InferenceExperimental DesignStatistics - MetaMediumData ScientistDesign a clustered notification experiment with guardrails
This question evaluates experimental-design and causal-inference competencies for cluster-randomized experiments, covering metric selection, power and design-effect calculations, intracluster correlation, spillover detection, sequential monitoring, guardrails, and operational rollout within the Analytics & Experimentation domain for a Data Scientist role. It is commonly asked to determine how applicants balance statistical rigor and real-world operational constraints—such as cluster choice, monitoring thresholds, and analysis strategy—testing both conceptual understanding and practical application in production experimentation.
Analytics & ExperimentationTechnical Screen - 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 - MetaHardData ScientistDesign a feed ads A/B test with guardrails
This question evaluates a data scientist's competency in experimental design, causal inference, statistical power analysis, and product-metric trade-offs within the Analytics & Experimentation domain, and is commonly asked to assess the ability to increase monetization while protecting user and creator experience.
Analytics & ExperimentationOnsite - MetaMediumSoftware EngineerDesign a fitness tracking app
This problem tests your ability to design a scalable backend for a fitness tracking application, focusing on high-frequency sensor data ingestion, geospatial route storage, and efficient retrieval of historical user activities.
System DesignOnline AssessmentScalabilityGeospatialNoSQL - 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
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