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Backend 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.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 1–18 of 18 results
- AirbnbHardBackend EngineerDesign a Rental Marketplace Backend
This problem tests your ability to design a distributed, high-scale rental marketplace platform, focusing on concurrency control for bookings, efficient geo-spatial searching, and data consistency.
System DesignOnsiteDistributed SystemsConcurrencyGeo-spatial - CoinbaseMediumBackend EngineerDesign a Real-Time Asset Price Service
Design a high-throughput, low-latency price ingestion and distribution service that normalizes multi-exchange market data, reconciles conflicting ticks, and delivers live prices to internal services and retail clients.
System DesignOnsiteDistributed SystemsWebSocketsReal-Time Data - DatabricksMediumBackend EngineerDesign a Distributed File System, Scoping the Requirements Yourself
Design a distributed file system from a one-line prompt, driving the scoping of workload, semantics, scale and durability yourself. Tests separating metadata from data, block replication and placement, read and write paths, failure recovery, and scaling the namespace for a staff-level backend role.
System DesignOnsite - HarveyMediumBackend EngineerDesign a secure document vault
This question evaluates a candidate's competencies in secure backend system design, covering authentication and authorization, metadata and object storage architectures, integrity verification for chunked uploads, scalability, and operational reliability.
System DesignOnsite - New RelicMediumBackend EngineerDesign a Kafka Consumer Service That Groups Trace Events by Trace ID
Design a distributed service that consumes trace events from Kafka, groups every event sharing a trace ID, and hands each complete trace to an existing processing function. Covers partitioning, in-memory versus external state, deciding when a trace is complete, and traces that stay open for hours.
System DesignOnsite - NuroHardBackend EngineerDesign Webhooks and Metric Aggregation
Design a webhook delivery platform and vehicle telemetry aggregation system. The solution covers multi-tenant subscriptions, at-least-once delivery, retries, signing, DLQs, endpoint isolation, high-volume ingestion, stream processing, raw storage, rollups, alerting, late events, and downsampling.
System DesignOnsite - OktaMediumBackend EngineerDesign Cross-Domain SSO and OIDC Access to Third-Party Tools
Design cross-domain SSO with OIDC authorization-code flow, separate site sessions, secure account linking, third-party federation, and delegated API authorization.
System DesignOnsite - OktaMediumBackend EngineerDesign Single Sign-On Across Two Acquired Sites With OIDC Federation
Design cross-domain single sign-on after one company acquires a second site on a different domain, then extend it to many sites and to delegated API access for third-party tools, covering the authorization-code flow, session separation, and the authentication-versus-authorization distinction.
System DesignOnsitesystem-designauthenticationoidc - OracleMediumBackend EngineerDesign a Distributed Rate Limiter
This problem tests the ability to design a scalable, low-latency distributed system for enforcing traffic quotas across multiple geographic regions with considerations for consistency and burst handling.
System DesignOnsiteDistributed SystemsRate LimitingScalability - OracleMediumBackend EngineerDesign a High-Volume Healthcare Data Ingestion Pipeline
This question tests the ability to design a resilient, high-throughput ETL pipeline for sensitive and messy healthcare data, focusing on fault isolation, data integrity, and architectural scalability.
System DesignOnsiteETLData PipelineScalability - 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 - RokuMediumBackend EngineerDesign a high-throughput ad exchange
This problem tests your ability to design a low-latency, high-throughput distributed system capable of managing real-time bidding (RTB) auctions for streaming video advertisements.
System DesignOnsiteDistributed SystemsLow LatencyHigh Throughput - SalesforceEasyBackend EngineerDesign a Chat Analytics Backend
This question evaluates a candidate's competence in designing large-scale analytics backends, covering data ingestion, event and metric schemas, near-real-time and historical analytics, metric computation and slicing, data freshness and deduplication, privacy and access control, operational monitoring, and the API/query layer.
System DesignOnsite - Scale AIEasyBackend EngineerDesign a Durable Task Scheduling Service
Design a resilient, distributed task scheduling service that decouples scheduling from execution, supporting both delayed one-time tasks and recurring cron jobs with strong durability and at-least-once delivery.
System DesignOnsiteDistributed SystemsTask SchedulerConcurrency - SpotifyMediumBackend EngineerDesign a Public Upload and Hosting Service for Playlist Cover Images
A Spotify system design question: design a service that lets users upload, replace and remove a public cover image for their playlists, served to the app and to third-party embeds. Follow-ups cover how an auditor would review image changes and how upload and processing failures are handled.
System DesignOnsite - TeslaMediumBackend EngineerDesign booking and settlement systems
This question evaluates backend system design competencies such as concurrency control, transactional integrity, reconciliation, file ingestion and processing, idempotency, API design, and operational reliability.
System DesignOnsite - ValonMediumBackend EngineerDesign Correct Stateful Services for Irregular Financial Events
A systems-design interview about correct stateful processing for sparse records, out-of-order loan events, investor payment allocation, and authenticated APIs. It emphasizes idempotency, ledgers, exact arithmetic, recovery, and auditability.
System DesignOnsite - ZooxHardBackend EngineerDesign a Ride-Hailing Platform
This question tests your ability to design a highly scalable, real-time geo-spatial matching system that handles low-latency requests for vehicle dispatching and location tracking.
System DesignOnsiteGeo-spatialScalabilityDistributed Systems