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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
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- 546
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- 11
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- 8
- Languages
Showing 1021–1050 of 1311 results
- RedditEasySoftware EngineerDesign a game leaderboard service
This question tests the ability to design a high-throughput, low-latency leaderboard service capable of handling frequent rank updates and read requests for millions of active users.
System DesignOnsiteCachingDatabasesScalability - RemitlyMediumStaff AI-Native EngineerBuild a Transfer-Fee Comparison Prototype
Design an extensible remittance fee-comparison engine that aggregates quotes across multiple providers, normalizes explicit fees and FX spreads, and gracefully surfaces provenance, staleness, and provider failures.
System DesignTechnical ScreenFintechAPI DesignData Pipelines - RemitlyHardSoftware EngineerDesign a Production-Ready URL Shortener
This question evaluates competency in designing a scalable, reliable, and secure production URL shortening service, covering API design, link data modeling and analytics, ID/token generation, caching and read/write paths, partitioning/replication/consistency choices, rate limiting and abuse mitigation, TTL handling and cleanup, and HA/DR and monitoring. Commonly asked in system design interviews to probe architectural trade-offs for high-read consumer services, it belongs to the System Design domain and emphasizes practical application of distributed systems and operational concepts rather than only conceptual theory.
System DesignOnsite - RemitlyEasySoftware EngineerDesign an IP Address Filtering Service
Design a low-latency service that allows or denies traffic using source or destination IP rules. Candidates must define conflict precedence, address normalization, versioned rollout, stale-state behavior, audit evidence, privacy-conscious logging, and safe rollback.
System DesignOnsite - RemitlyHardSoftware EngineerWhiteboard and Deep Dive a Past Project
This question evaluates a candidate's end-to-end system design skills, including architecture decomposition, trade-off analysis, data consistency choices, scalability and resiliency patterns, and integration of operational practices for a user-facing distributed service.
System DesignOnsite - RenderMediumSoftware EngineerRate Limit an API During a Traffic Attack
Design API rate limiting with token buckets, layered identities, endpoint costs, distributed-state tradeoffs, and measurable protection of legitimate traffic.
System DesignTechnical Screen - ReplitMediumSoftware EngineerDesign a Multi-Channel Notification System
Design a resilient, multi-channel notification service that routes notifications across in-app, email, SMS, and push channels while honoring user preferences, idempotency, rate limits, and provider status tracking.
System DesignOnsiteDistributed SystemsMessage QueuesAPI Design - Resolve.AiMediumSoftware EngineerDesign a Weighted Log Distributor
This question tests your ability to design a distributed system that routes incoming log streams to multiple storage clusters based on specified weight configurations while ensuring high availability and fault tolerance.
System DesignOnline AssessmentLoad BalancingDistributed SystemsData Pipelines - Retell AIHardSoftware EngineerDesign a Cloud Call-Center Platform for Programmatic Outbound Calls
This question evaluates a candidate's ability to design a distributed, asynchronous system under hard external rate and capacity constraints. It tests system design fundamentals such as queueing, backpressure, state-machine modeling, and multi-tenant fairness, commonly asked to assess architectural reasoning at a practical, applied level rather than pure theory.
System DesignTechnical Screen - Retell AIMediumSoftware EngineerDesign a Smooth Per-Customer Calls-Per-Second Controller
Design a distributed outbound call pacing service that enforces smooth per-tenant calls-per-second (CPS) rate limits while ensuring durable queueing, priority scheduling, and safe failover.
System DesignTechnical ScreenRate LimitingDistributed SystemsTask Scheduling - Retell AIHardSoftware EngineerDesign and Implement a Mini SQL Query Engine
This question evaluates a candidate's ability to design and build a small SQL query engine, covering tokenization, parsing, and query execution over in-memory tables. It tests system design and compiler-style thinking, including how to scope a large problem into an extensible v1 and reason about extending it with sorting, aggregation, and joins. This is a system design and practical implementation question assessing both architectural judgment and coding ability.
System DesignTechnical Screen - Retell AIMediumSoftware EngineerDesign collaborative document editing backend
This question evaluates a candidate's ability to design real-time collaborative systems, focusing on distributed systems concepts, concurrency control, consistency models, synchronization, and scalable backend architecture.
System DesignOnsite - RetoolHardSoftware EngineerDesign car rental schema and APIs
This question evaluates data modeling, transactional integrity, concurrency control, REST API and workflow design, and system scalability within the car rental domain in the System Design category.
System DesignTechnical Screen - RevolutMediumSoftware EngineerDesign automatic travel insurance enrollment triggered by customer location
A system design exercise for a banking app that automatically enrolls opted-in customers in travel insurance when location signals show they are abroad. It tests requirements scoping, an event-driven pipeline, idempotent enrollment with an insurer, data modeling, scaling reads and writes, and failure handling.
System DesignOther - RevolutMediumSoftware EngineerDesign multi-region banking data synchronization
This question evaluates competency in distributed systems and data consistency for financial applications, emphasizing replication, transaction correctness, conflict resolution, idempotency, and operational resilience.
System DesignTechnical Screen - RipplingHardSoftware EngineerBuild Reliable Employee-Operations and Expense Intelligence Systems
A multi-part system-design interview covering tagged event aggregation, driver-pay accounting, employee offboarding, and an LLM-backed expense assistant. Candidates must distinguish approximate dashboards from exact billing and design reliable workflows across failing dependencies.
System DesignOnsite - RipplingMediumSoftware EngineerDesign News Pull Scheduling, Article Storage, and Topic Reads
Design a scalable topic-based news aggregation system covering distributed feed scheduling, idempotent article ingestion, stable pagination, and a low-latency read path.
System DesignTechnical ScreenDistributed SystemsCachingJob Scheduling - RipplingMediumSoftware EngineerDesign a Deduplicated Personalized News Feed
Design a news aggregation and recommendation system that ingests multi-publisher articles, clusters coverage of identical real-world events, and serves a personalized, deduplicated feed with low latency.
System DesignTechnical Screensystem-designnews-feedclustering - RipplingHardSoftware EngineerDesign a Google News-like aggregator
This question evaluates system design skills for building a large-scale, multi-region news aggregation platform, assessing competencies in ingestion architecture, deduplication and clustering, indexing and retrieval, personalization and ranking, and operational concerns like monitoring, consistency, and compliance.
System DesignOnsite - RipplingHardSoftware EngineerDesign a Hotel Booking System
This question tests your ability to design a distributed system that manages transactional integrity, high concurrency during bookings, and efficient searching for room availability.
System DesignOnsiteConcurrencyDatabase ModelingDistributed Systems - RipplingMediumSoftware EngineerDesign a Hotel Search and Reservation System
Design an end-to-end hotel search and booking platform balancing high-throughput search with strictly consistent, transactional room inventory management across continuous date ranges.
System DesignOnsitesystem-designdistributed-systemsconcurrency - RipplingMediumSoftware EngineerDesign a News Aggregation Feed
This question evaluates expertise in large-scale system design—specifically data ingestion, article clustering/deduplication, feed ranking and personalization, API and data-model design, scalability, reliability, and monitoring—within the System Design domain.
System DesignTechnical Screen - RipplingMediumSoftware EngineerDesign a News Aggregation Service
Design a scalable news aggregation platform that ingests high-volume publisher feeds, clusters and deduplicates coverage into cohesive stories, and serves fresh, personalized feeds with sub-second latency.
System DesignTechnical ScreenData PipelinesClusteringCaching - RipplingMediumSoftware EngineerDesign a News Aggregation System (Google News-style)
Design an end-to-end news aggregation platform that ingests articles at scale, deduplicates syndicated content, clusters articles into evolving story threads, and serves low-latency feeds.
System DesignTechnical ScreenDistributed SystemsData PipelinesClustering - RipplingMediumBackend EngineerDesign a News Aggregator That Builds Personalized Feeds from Publisher APIs
System design question on building a news aggregator that polls many publisher APIs, stores only article metadata, and serves each user a paginated feed from the publishers and categories they follow. It tests polling schedules and stop conditions, rate-limit and outage handling, feed merging with deduplication, stable cursors, and bounded storage.
System DesignOnsite - RipplingMediumSoftware EngineerDesign a Personalized News Feed Aggregator
Design a personalized news-feed system that ingests articles from many sources and builds a home feed. Connect requirements and APIs to data modeling, consistency, scaling, failure recovery, observability, and the important design trade-offs.
System DesignOnsite - RipplingMediumSoftware EngineerDesign a Scalable News Feed
This problem tests your ability to design a high-scale feed delivery system, specifically focusing on the trade-offs between 'push' (fan-out) and 'pull' (fan-in) models for delivering content to users.
System DesignOnsiteScalabilityDatabase ShardingCaching - RipplingMediumSoftware EngineerDesign a User Behavior Tracking (Clickstream Analytics) System
Design a scalable clickstream analytics pipeline capable of ingesting high-throughput user interaction events, handling duplicate and out-of-order data, and supporting both real-time aggregated dashboards and raw behavioral query paths.
System DesignTechnical ScreenStream ProcessingData PipelinesOLAP - RipplingMediumSoftware EngineerDesign a delivery cost system
A Rippling software-engineer system-design screen: build an object-oriented, in-memory delivery cost dashboard that registers drivers with hourly rates, records completed deliveries, and reports total cost, paid and unpaid amounts via an idempotent payUpTo cutoff, and the maximum number of drivers simultaneously delivering in the last 24 hours. It tests time-interval modeling, exact monetary arithmetic without floating-point drift, sweep-line concurrency counting, idempotency, time-zone handling, and thread-safe O(1) dashboard reads. The walkthrough covers both prorated and whole-delivery payment semantics, a full Python reference implementation, and the production hardening a real payroll service would need.
System DesignTechnical Screen - RipplingHardSoftware EngineerDesign a flexible expense reimbursement system
This question evaluates system design and architecture skills for building a policy-driven, explainable expense reimbursement platform, specifically testing competencies in rule engines and DSL/config design, versioning and immutable evaluations, group-level aggregation and conflict resolution, data modeling and partitioning for scale, API and workflow design, observability/auditing, and access control. As a System Design interview prompt it is commonly asked because it forces candidates to articulate trade-offs between extensibility, explainability, consistency, and performance; the assessment targets practical application of architectural principles with strong conceptual reasoning.
System DesignTechnical Screen
Reddit
Remitly
Retell AI
Revolut
Rippling