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System Design 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
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 301–330 of 721 results
- J.P. MorganMediumSoftware Engineer IIExplain a Project Architecture End to End
Tests your ability to present a production system architecture end-to-end, detailing data flow, ownership boundaries, database indexing and partitioning strategies, resilience patterns, and concrete architectural trade-offs.
System DesignOnsiteDatabase OptimizationArchitectureData Modeling - J.P. MorganMediumSoftware Engineer IIOptimize User-and-Region Queries on a Million-Row Table
Evaluate and design database access patterns, indexing strategies, and scaling techniques (partitioning, sharding, replication) for a financial user-profile system with high regional skew and frequent lookups.
System DesignOnsiteDatabase OptimizationIndexingPartitioning - Jane StreetEasySoftware EngineerDesign exchange–trading system message flow
This question evaluates a candidate's knowledge of distributed messaging protocols, fault-tolerant system design, and financial trading interface competencies, including defining message contracts, session management, and guarantees like idempotency and ordering.
System DesignOnsite - Jane StreetEasySoftware EngineerValidate order book data across multiple databases
This question evaluates a candidate's competency in designing data-validation and reconciliation systems for financial order books, including defining invariants, ensuring cross-database consistency, and handling edge cases like partial fills, cancels, out-of-order events, duplicates, and replayed messages.
System DesignOnsite - LangchainMediumSoftware EngineerOptimize Object-Backed APIs and Design an LLM Observability Platform
Design a high-throughput LLM observability and tracing platform that reliably captures spans, aggregates token billing, and provides low-latency trace retrieval over an object-storage backend.
System DesignOnsiteObservabilityObject StorageStreaming - Lead BankMediumSoftware EngineerDesign Room-Level Hotel Reservations Without Double Booking
This problem tests the ability to design a distributed reservation system that ensures strong consistency for inventory management while handling high-concurrency read operations.
System DesignOnsiteConcurrencyDatabaseDistributed Systems - Lead BankMediumSoftware EngineerDesign a hotel reservation system
This problem tests your ability to design a distributed reservation system that handles high concurrency, prevents double-booking, and maintains eventual consistency with external payment services.
System DesignOnsiteConcurrencyDistributed SystemsDatabase Modeling - LegoraMediumSoftware EngineerDesign Direct File Uploads for a Chat Application
Design a scalable direct-to-object-store file upload pipeline for a chat platform, focusing on presigned authorization, durable lifecycle tracking, asynchronous validation, and orphan reconciliation.
System DesignOnsiteObject StorageFile UploadDistributed Systems - LegoraHardSite Reliability EngineerDesign a Compliance Audit Log Platform
Design an immutable, multi-tenant compliance audit logging platform that supports canonical ingestion, cryptographic tamper evidence, gap detection, and efficient legal investigation queries at scale.
System DesignOnsiteDistributed SystemsSRESecurity - LinkedInMediumSoftware EngineerBlock Malicious IPs at an API Gateway Across Data Centers
Design gateway IP-block enforcement with trusted client addresses, versioned rules, fast local checks, expiration, and multi-data-center propagation.
System DesignOnsite - LinkedInMediumSoftware EngineerCollect and Query Recent User Activity
Design a scalable user activity ingestion and querying system capable of computing metrics over rolling time windows (1 minute, 1 hour, 24 hours) with deduplication and late-arriving event handling.
System DesignOnsitesystem-designdistributed-systemsstream-processing - LinkedInMediumSoftware EngineerDesign Keyword Search over Posts with Exclusions and Frequency Ranking
A system design question on keyword search over social posts: find the posts that contain a keyword without scanning them all, support queries that require one keyword and exclude another, and order results by how often the keywords appear. Tests indexing, query evaluation, sharding, pagination and ranking trade-offs.
System DesignOnsite - LinkedInHardSoftware EngineerDesign Top K ranking system
Design Top K ranking system 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 - LinkedInMediumDevOps EngineerDesign a CI Job Scheduler with Live Build Output
Design a scalable continuous integration (CI) platform that schedules dependency-aware build jobs across worker fleets and streams live console output to end users.
System DesignOnsiteCI/CDDistributed SystemsDevOps - LinkedInMediumSoftware EngineerDesign a CI/CD Task Scheduler
Design the core distributed task scheduling engine for an enterprise CI/CD platform that coordinates DAG-based workflows across heterogeneous worker pools.
System DesignOnsiteDistributed SystemsTask SchedulingCI/CD - LinkedInMediumSoftware EngineerDesign a Distributed Key-Value Store for a Small Company's Internal Use
Design a distributed key-value store for internal use at a small company. The question tests comparing centralized, decentralized and hybrid architectures, and depth on partitioning, rebalancing, replication, failure handling, consistency, hot keys and availability at a senior infrastructure level.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign a Global Calendar Service
This question evaluates competence in designing scalable, time-zone aware calendaring systems, covering API and data model design, recurrence representation, daylight saving semantics, conflict detection, storage strategy, and consistency trade-offs.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign a Personalized Job Suggestions Page for LinkedIn Members
Design the LinkedIn page that suggests open jobs to a signed-in member, from candidate retrieval and filtering to ranking, pagination and serving. Tests large-scale recommendation architecture, freshness for new and closed postings, feedback logging, latency budgets and graceful degradation.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign a Ranked Social Feed with Hybrid Fan-Out
Design a scalable, read-heavy ranked social feed supporting millions of users. The system must balance fan-out-on-write and fan-out-on-read while ensuring read-your-own-writes consistency for authors.
System DesignOnsiteDistributed SystemsCachingSocial Network - LinkedInMediumSoftware EngineerDesign a Scalable Calendar Service
Design calendar event storage and time-range reads, explain concurrent edits and scaling, and clarify recurrence and notification requirements.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign a Scalable Error Message Counting Service
Design a service that receives application error messages and reports how often each distinct error occurs over time. It tests grouping varied messages into error signatures, absorbing bursty write traffic during incidents, time-windowed aggregation, top-error queries and count accuracy under failures.
System DesignOnsite - LinkedInEasySoftware EngineerDesign a Top-K Ranking Service
This question tests the ability to design a distributed, low-latency system capable of maintaining and serving a real-time 'Top-K' list of items (e.g., trending hashtags) across a massive stream of incoming data.
System DesignOnsiteScalabilityStreamingCaching - LinkedInMediumSoftware EngineerDesign a company-wide monitoring system
This question evaluates skills in designing large-scale observability and monitoring systems, covering telemetry collection (metrics, logs, traces), high-throughput ingestion, storage and scaling strategies, alerting pipelines, and operational trade-offs like cardinality, retention, and backpressure.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign a malicious-URL checking service using an isMalicious API
This question tests your ability to design a high-throughput, low-latency URL reputation checking service, focusing on caching strategies, scalability, and system resilience.
System DesignOnsiteCachingScalabilityResilience - LinkedInMediumSoftware EngineerDesign a metrics platform without alerting
This problem tests your ability to design a high-throughput time-series metrics system, focusing on ingestion pipelines, efficient storage schema for multi-dimensional data, and query performance.
System DesignOnsiteTime-SeriesScalabilityData Modeling - LinkedInHardSoftware EngineerDesign a scalable calendar system
This question evaluates a candidate's ability to design a scalable, multi-tenant calendar platform, testing competencies in distributed systems architecture, API and data-model design for events/recurrence/time zones, access control and privacy boundaries, notification pipelines, and external integration.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign a scalable key-value store
This system design question evaluates expertise in distributed systems and scalable storage architecture within the System Design domain, focusing on data partitioning, replication, durability, consistency models, and low-latency operation.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign an exception monitoring system with top‑K
This question tests the ability to design a high-throughput distributed system capable of ingesting, deduplicating, and aggregating exception logs to provide real-time top-K statistics.
System DesignOnsiteStreamingScalabilityData Modeling - LinkedInMediumSoftware EngineerDesign an in-memory key-value store using maps
This question evaluates skills in in-memory data modeling, concurrent access control, time-complexity reasoning for expected O(1) operations, and storage engine considerations such as durability, compaction, and TTL when restricting indexing to map/dictionary primitives.
System DesignOnsite - LinkedInMediumSoftware EngineerDesign scalable job scheduler and query dashboard
This question evaluates a candidate's system design skills in building a scalable, fault-tolerant job scheduling system and efficient near-real-time time-window querying, focusing on distributed scheduling, storage and indexing strategies, partitioning, and reliability guarantees, and is commonly asked to probe trade-offs among scalability, latency, availability, and consistency. Belonging to the System Design domain, it examines both high-level architectural thinking and practical application-level considerations such as data modeling, query/index design, operational concerns like hot partitions, and horizontal scaling.
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J.P. Morgan
Jane Street
LinkedIn