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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 31–55 of 55 results
- OracleMediumBackend EngineerExplain How You Use AI in Software Engineering
This question assesses the candidate's practical experience with AI-assisted coding tools, their ability to critically evaluate machine-generated output, and their awareness of engineering rigor regarding security and code quality.
Behavioral & LeadershipOnsiteSoftware EngineeringGenerative AICode Review - OracleMediumBackend EngineerExplain a Difficult Technical Decision
This question assesses a candidate's ability to articulate complex technical trade-offs, stakeholder management, and the ability to reflect on past decision-making processes.
Behavioral & LeadershipOnsiteBehavioralArchitectureDecision Making - OracleMediumBackend EngineerFind the Best Profit from One Stock Trade
Tests array traversal, greedy state tracking, and achieving optimal O(n) time and O(1) space complexity for trade optimization.
Coding & AlgorithmsOnsiteArrayDynamic ProgrammingGreedy - OracleMediumBackend EngineerHandle a Tight Deadline You Could Not Meet
This question assesses the candidate's ability to identify project risks early, manage stakeholder expectations through transparent communication, and implement process improvements to prevent recurrence.
Behavioral & LeadershipOnsiteBehavioralLeadershipProject Management - OracleMediumBackend EngineerReturn the K Most Frequent Values with a Larger-Value Tie-Break
This problem tests proficiency with hash maps for frequency counting and custom sorting logic using priority queues or sorting algorithms.
Coding & AlgorithmsOnsiteHash MapSortingPriority Queue - OracleMediumBackend EngineerSplit a String into Exactly Three Palindromes
Tests string partitioning, palindrome verification, and algorithmic optimization using dynamic programming or two pointers.
Coding & AlgorithmsOnsiteStringDynamic ProgrammingTwo Pointers - 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 - RipplingMediumBackend EngineerProcess a Task List: Deduplicate, Drop Completed, Sort by Priority, and Nest Subtasks
Senior backend coding question: process a batch of scheduler tasks by removing duplicates on description and due date, dropping completed tasks, sorting by priority, and placing each subtask directly after its parent. It tests clarifying ambiguous policies, orphan and cycle handling, O(n log n) design, and verified use of an AI coding assistant.
Software Engineering FundamentalsOnsite - RipplingMediumBackend EngineerSenior Backend Hiring Manager Deep Dive: Idempotency, SLAs, Changed Decisions, and Pushback
Senior backend hiring manager round covering your proudest project with deep dives on idempotency and SLA definition and monitoring, a technical decision you reversed, a design a colleague challenged, and company-specific motivation. It tests ownership, technical depth, judgment under disagreement, and honest self-reflection.
Behavioral & LeadershipOnsite - 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 - RokuMediumBackend EngineerExplain concurrency and distributed fundamentals
This question tests fundamental knowledge of thread-safe collections in Java and core distributed systems architectural patterns, specifically partitioning strategies.
Software Engineering FundamentalsOnsiteJavaConcurrencyDistributed Systems - 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 EngineerBuild a CSV-to-JSON Classification Service
Implement a resilient data pipeline service that parses CSV records, enriches them using an external classification client with validation and retries, and writes ordered, structured JSON Lines output safely.
Software Engineering FundamentalsOnsiteData PipelinesConcurrencyError Handling - 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 EngineerA Time You Lifted Your Team's Morale and Energy
A Spotify behavioral question asking for a time you brought positivity to your team. It tests whether you notice morale problems, take specific and genuine actions to address them, stay candid about real issues, and can show the effect on the team.
Behavioral & LeadershipOnsite - 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 - SpotifyMediumBackend EngineerHow You Use AI Tools as an Engineer and Drive Their Adoption on Your Team
A Spotify behavioral question in two parts: how you use AI tools in your engineering work and side projects, and how you have pushed for AI adoption on your team. It tests judgment about AI output, verification habits, data safety, and influencing teammates.
Behavioral & LeadershipOnsite - SpotifyMediumBackend EngineerOn-Call Case Study: Debugging a Misbehaving Production Server
A Spotify on-call case study: as the engineer paged about a misbehaving production server, investigate by asking for metrics, logs and command output. It tests triage, impact assessment, systematic host and service diagnostics, mitigation trade-offs and incident follow-through.
Software Engineering FundamentalsOnsite - SpotifyMediumBackend EngineerVisit-Pattern Counter: Multi-Input Runtime Analysis and Production Hardening
A Spotify backend coding follow-up: for a function that finds the three-website visit pattern followed by the most distinct users, analyze time and memory using separate input dimensions such as records, users, longest per-user history and distinct sites. It also asks which functional and style changes the code needs before it ships in production.
Software Engineering FundamentalsOnsite - TeslaMediumBackend EngineerCompute time to burn tree
This question evaluates proficiency with tree algorithms, distance computation, and propagation modeling, testing the ability to reason about how a process spreads across parent-child relationships in a tree.
Coding & AlgorithmsOnsite - TeslaMediumBackend EngineerDescribe conflict and proudest work
This question evaluates interpersonal conflict resolution, collaboration, ownership, and impact-communication skills within the Backend Engineer role and falls under the Behavioral & Leadership domain.
Behavioral & LeadershipOnsite - 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 - TeslaMediumBackend EngineerExplain reliability and runtime fundamentals
This question evaluates understanding of reliability and runtime fundamentals in backend engineering, covering competencies such as fault tolerance, end-to-end request lifecycles, API gateway degradation, storage engine selection for search, and the distinction between compilers and interpreters.
Software Engineering FundamentalsOnsite - 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
Oracle
Rippling
Salesforce
Scale AI
Spotify
Tesla
Zoox