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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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- 8
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Showing 3271–3300 of 3640 results
- StubHubMediumSoftware EngineerDesign Internal Chat and Re-engagement Emails
This question evaluates a candidate's competency in designing scalable, real-time messaging systems and re-engagement workflows, covering distributed systems concepts such as WebSocket-based bidirectional communication, presence, cross-server message routing, message persistence, APIs, storage trade-offs, inactivity detection, and email-triggering workflows. Commonly asked in the System Design category, it tests high-level architectural reasoning and practical application of scalability, reliability, and failure-handling trade-offs when integrating persistent WebSocket connections, cross-server routing, and background email jobs in a distributed platform.
System DesignOnsite - StubHubMediumSoftware EngineerDesign a Global Marketing Email Platform
This problem tests your ability to design a high-throughput, fault-tolerant email delivery system that handles scheduling across time zones, manages email templates, and provides basic analytics.
System DesignOnsiteScalabilityDistributed SystemsMessaging - StubHubMediumSoftware EngineerImplement a Composable Event Recommendation Engine
This problem tests your ability to design a flexible, object-oriented recommendation pipeline using the Strategy and Composite patterns to handle multiple scoring rules and fallback logic.
Coding & AlgorithmsOnsiteOOPStrategy PatternRecommendation Systems - SumologicMediumSoftware EngineerSolve substring and access-log problems
This problem tests your ability to process log data and perform string manipulation by identifying users who visited a specific URL across multiple days and determining the longest common substring between two modified strings.
Coding & AlgorithmsOnsiteStringsHashingDynamic Programming - SunriseEasySoftware EngineerExplain the least squares method
Explain the least squares method evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Machine LearningOnsite - TemuEasySoftware EngineerFind missing rank in a straight
This question evaluates a candidate's ability to map and manipulate encoded card ranks, reason about consecutive sequences with Ace-as-low or Ace-as-high semantics, and identify a missing element within a constrained set.
Coding & AlgorithmsOnsite - TemuEasySoftware EngineerFind next greater element for subset
This question evaluates understanding of sequence analysis and array-processing competencies, including mapping elements between arrays, index lookup, and designing efficient order-dependent algorithms for the "next greater element" problem.
Coding & AlgorithmsOnsite - 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 - TeslaMediumSoftware EngineerCoordinate Counter Updates Across Threads
Tests multi-threaded synchronization, atomic operations, barrier synchronization, and coordinated condition handling across concurrent threads.
Software Engineering FundamentalsOnsiteconcurrencymultithreadingsynchronization - TeslaEasySoftware EngineerCount the Ways to Decode a Numeric Cipher
This problem tests your ability to solve a counting problem using dynamic programming by identifying overlapping subproblems in a sequence of numeric mappings.
Coding & AlgorithmsOnsiteDynamic ProgrammingString ManipulationAlgorithms - 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 - TeslaHardSoftware EngineerDesign a Distributed Blob Storage System for Build Artifacts
Design a distributed storage system for build artifacts, similar to a distributed NoSQL database but storing opaque blobs with looser ACID requirements. It tests separating immutable data from consistent metadata, upload atomicity, replication and repair, handling download fan-out, and safe retention and garbage collection.
System DesignOnsite - TeslaMediumSoftware EngineerDesign a Video Sharing Platform
Design a resilient, large-scale video sharing and streaming platform that handles multi-gigabyte uploads, asynchronous transcoding, and low-latency global delivery. This question tests your ability to design chunked upload protocols, idempotent processing pipelines, and CDN-backed adaptive streaming architectures.
System DesignOnsiteDistributed SystemsVideo StreamingCDN - TeslaHardMachine Learning EngineerDesign an LLM math-solving chain
Design an LLM math-solving chain evaluates ML product requirements, data/labeling, modeling, serving architecture, evaluation, monitoring, and trade-offs in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
ML System DesignOnsite - TeslaMediumSoftware EngineerDesign an Order Fulfillment System
Design an order-fulfillment system and explain its major components, data flow, and reliability trade-offs.
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 - 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 - TeslaHardSoftware EngineerFlatten a Linked List with Nested Side Branches into One Doubly Linked List
A linked list whose nodes may each carry one side branch, with branches nested like a binary tree, must be flattened into a single doubly linked list with every branch spliced between its parent and the parent's original successor. It tests pointer rewiring, ordering rules for nested branches, and handling very deep nesting.
Coding & AlgorithmsOnsite - TeslaHardSoftware EngineerFrom a Monorepo Commit to an Over-the-Air Vehicle Update, and Choosing What to Build
Trace everything that happens between an engineer pushing a commit to a monorepo and the resulting software being installed on customers' cars, then explain how the monorepo decides which targets to build and test and in what order. It tests CI and release gating, artifact provenance, staged over-the-air rollout, safe in-vehicle installation, and dependency-graph builds.
System DesignOnsite - TeslaMediumSoftware EngineerHow to Identify Best Battery Group
This question evaluates understanding of statistical inference, experimental design, and metric construction for binary test outcomes, including defining composite quality measures, handling unequal sample sizes, quantifying uncertainty, and addressing multiple-comparison issues.
Machine LearningOnsite - TeslaMediumSoftware EngineerReason About Alternating Positive and Negative Values
This problem tests your ability to manipulate array elements in-place while managing constraints on stability and the treatment of special values like zeros.
Software Engineering FundamentalsOnsiteArraysTwo-PointersIn-place - TeslaMediumSoftware EngineerReason About Character Paths in a Grid
Tests depth-first search with backtracking on a 2D grid, covering cycle prevention, branching path exploration, termination criteria, and lexicographical ordering.
Software Engineering FundamentalsOnsitedfsbacktrackingmatrix - TeslaHardSoftware EngineerSenior Project Deep Dive: Design Rationale, Your Most Complex Project, Questions for the HM
A senior infrastructure loop probes past work in a resume deep dive on design rationale and rejected alternatives, then the hiring manager asks for your most complex project and your questions for them. It tests whether project scope meets the senior bar, clear ownership, measurable impact, and the habit of asking probing follow-up questions.
Behavioral & LeadershipOnsite - TeslaEasySoftware EngineerShortest Bridge to Connect Two Islands
Tests matrix traversal techniques, specifically using DFS/BFS to identify connected components and multi-source BFS to find the shortest path between them.
Coding & AlgorithmsOnsitegraphbfsdfs - TeslaHardSoftware EngineerTroubleshoot Processes That Randomly Crash While Being Created on Linux Cluster Hosts
Processes scheduled onto a Linux server cluster randomly crash while being created, and the interviewer plays the system while you hunt for a planted cause. It tests Linux troubleshooting commands for processes, memory, network and disk I/O, and reasoning about how cron jobs spawning tens of thousands of threads can break other workloads.
Software Engineering FundamentalsOnsite - The Trade DeskMediumSoftware EngineerCalculate Bowling Game Score
This problem tests your ability to manage state and look-ahead logic when processing a sequence of events (bowling rolls) governed by specific conditional scoring rules.
Coding & AlgorithmsOnsiteArraysLogicSimulation - ThumbtackMediumData ScientistCompare list/dict; parse JSON/CSV at scale
This question evaluates understanding of Python data structures (list vs dict), algorithmic time and memory complexity, ordering guarantees in CPython, large-scale parsing and streaming of JSON/CSV, and robust data-cleaning and error-handling strategies.
Data Manipulation (SQL/Python)Onsite - ThumbtackMediumData ScientistCompute weighted response rates by job category
This question evaluates a candidate's data manipulation and statistical estimation skills, including pandas-based aggregation, invitation-weighted rate calculation, confidence-interval computation, and robust handling of data-quality issues, in the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Onsite - ThumbtackHardData ScientistDesign a robust pro-ranking A/B test
It evaluates experimental design and causal inference competencies for two-sided marketplaces, focusing on metric definition and guardrails, randomization to limit interference, power and sample-size estimation, bias controls, monitoring and sequential stopping, and attribution of uplift versus cannibalization.
Analytics & ExperimentationOnsite - ThumbtackMediumData ScientistImplement min, mean, median robustly
This question evaluates implementation skills in basic descriptive statistics (min, mean, median), numerical stability in online aggregation methods, robust handling of edge cases like None/NaN and extreme numeric ranges, and algorithmic complexity reasoning in the Coding & Algorithms domain for a Data Scientist role.
Coding & AlgorithmsOnsite
StubHub
Temu
Tesla
The Trade Desk
Thumbtack