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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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Showing 3991–4020 of 9403 results
- HarveyMediumBackend EngineerImplement tag matcher and filesystem
This combined prompt evaluates string-processing and parsing skills for tag matching and design/implementation skills for an in-memory file system, measuring competencies in exact whole-word matching, case normalization, punctuation and duplicate handling, path parsing, hierarchical data structures, and file API behaviors.
Coding & AlgorithmsOnsite - HarveyMediumSoftware EngineerIn-Memory File System: Create, Track Duplicates, and List
Design an in-memory file system supporting directory creation, file creation with automated duplicate-name collision resolution, content retrieval, and directory listing.
Coding & AlgorithmsOnsiteTrieDesignTree - HarveyMediumSoftware EngineerIncremental Variable Resolver for a Build Pipeline
Build an in-memory variable resolver for a CI configuration system in three stages: plain integer variables, expression variables that reference other variables, then cycle detection with recomputation limited to the affected dependents. Checks whether a candidate can grow a design incrementally, respect a correct computation order, and reason about a dependency graph under change.
Software Engineering FundamentalsTechnical Screengraphsdependency-resolutiondesign - HarveyMediumSoftware EngineerMini Spreadsheet with Formulas Evaluated in set_cell and Cycle Rejection
A three-part coding exercise: build a mini spreadsheet with set_cell and get_cell, add formulas that sum constants and cell references with values computed eagerly in set_cell, and detect and reject circular dependencies. It tests dependency graphs, ordered recomputation and cycle checks.
Software Engineering FundamentalsTechnical Screen - HarveyMediumSoftware EngineerOwnership, Tough Feedback, and an Important Problem Outside Your Focus Area
Three behavioral questions from a hiring manager screen: a project you owned in the last year, tough feedback you received, and a time you discovered an important problem outside your immediate focus area. It tests ownership, coachability and judgment about raising issues beyond your own scope.
Behavioral & LeadershipTechnical Screen - HarveyMediumSoftware EngineerProject Deep Dive + Core-Values Behavioral Round
This interview module assesses your technical ownership, architectural decision-making, and alignment with engineering core values such as velocity, rigor, and customer obsession.
Behavioral & LeadershipOnsitebehavioralproject-deep-diveleadership - HarveyMediumBackend EngineerResolve conflict across teams
This question evaluates conflict resolution, stakeholder alignment, cross-team communication, and leadership competencies in the context of engineering coordination, classified under Behavioral & Leadership for a backend engineer role.
Behavioral & LeadershipOnsite - HarveyMediumSoftware EngineerSpreadsheet Class With Set/Get, Cell-Reference Formulas and Cycle-Rejecting Writes
Implement an in-memory spreadsheet class in three steps: set and get integer cell values, support formulas that reference other cells, and reject any write that would create a circular reference while leaving the sheet unchanged. It tests dependency tracking, update propagation and cycle detection.
Software Engineering FundamentalsTechnical Screen - HarveyMediumSoftware EngineerSpreadsheet Class with Formula Cells, Recalculation and Cycle Detection
Build an in-memory spreadsheet class in three stages: integer cells with set_cell and get_cell, formula cells such as =B1+C1+1 with explicit handling of never-set cells and recomputation on every write, then cycle detection and recomputing only dependent cells. Tests incremental design, evaluation order and dependency graphs.
Software Engineering FundamentalsTechnical Screen - HarveyMediumSoftware EngineerSpreadsheet Formula Engine with Cycle Detection
Design an in-memory spreadsheet formula engine supporting cell assignments, formula evaluation with dependencies, and cycle detection. The question tests directed graph modeling, topological invalidation, and cycle detection algorithms.
Coding & AlgorithmsTechnical Screengraphcycle-detectiontopological-sort - HarveyMediumMachine Learning EngineerTraining LLM Agents for Long-Context, Long-Horizon Tasks: Environments and Rewards
An ML research discussion on training language-model agents for long-context, long-horizon tasks. It tests the training recipe from context extension through supervised trajectories to RL, the design of reproducible training environments, and reward design that resists reward hacking over long trajectories.
Machine LearningOnsite - HeadlandsMediumData ScientistC++ Sliding-Window Mean of a Float Array With Inf, -Inf and NaN Handling
Implement an O(n) sliding-window mean over a 32-bit float array containing IEEE-754 special values (+inf, -inf, NaN) without poisoning subsequent windows or suffering numerical drift.
Software Engineering FundamentalsOnline Assessmentcppsliding-windowieee-754 - HeadlandsMediumData ScientistCompare Candy-Color Guessing Experiments with Different Sample Sizes
Evaluate and compare evidence from two binomial experiments with different sample sizes and hit rates against a random guessing null hypothesis.
Statistics & MathTechnical Screenstatisticshypothesis-testingbinomial-distribution - HeadlandsMediumData ScientistWhat Cross-Validation Reduces: Bias, Variance, Type I or Type II Error
This question tests your conceptual understanding of how k-fold cross-validation affects the generalization error and how the choice of 'k' influences the trade-off between bias and variance in model performance estimation.
Machine LearningOnline AssessmentModel EvaluationCross-ValidationStatistics - HeadlandsMediumData Scientistt-Stat With an Added Orthogonal Regressor, Live Sharpe Check, and Absolute-Loss Estimator
Solve three core quantitative problems covering OLS regression mechanics under orthogonal regressors, statistical significance of backtested Sharpe ratios in live deployment, and loss-function minimization for L1 error.
Statistics & MathOnline AssessmentEconometricsSharpe RatioLinear Regression - HeadwayMediumSoftware EngineerBehavioral: Deciding With Limited Data, a Process Built With AI, Spec-Driven Delivery
A behavioral screen with three prompts: a decision made with limited data, a process you implemented with AI, and a project delivered with minimal manual effort through spec-driven development. It tests judgment under uncertainty, verification of AI output, and turning requirements into a specification that drives the work.
Behavioral & LeadershipTechnical Screen - HeadwayMediumSoftware EngineerBuild a Dual Fixed-Window Rate-Limiting Middleware
Tests your ability to design and implement a thread-safe, dual fixed-window rate limiter and integrate it cleanly as HTTP middleware in an asynchronous Python framework.
Software Engineering FundamentalsOnsiteFastAPIConcurrencyRate Limiting - HeadwayMediumSoftware EngineerDebug a Stale Insurance Eligibility Status
Tests your ability to resolve data staleness and synchronization bugs between denormalized cache records and immutable event snapshots, while establishing clear domain invariants and handling out-of-order writes.
Software Engineering FundamentalsOnsiteSystem DesignData ModelingConcurrency - HeadwayMediumSoftware EngineerDebug and extend obstacle-run statistics classes
This question evaluates object-oriented design, debugging, algorithmic reasoning, and probabilistic simulation competencies by requiring fixes to class behavior, implementation of aggregate statistics, and a Monte Carlo-based probability estimator.
Coding & AlgorithmsTechnical Screen - HeadwayMediumSoftware EngineerDesign a Rental Search and Booking Platform from Startup to Scale
Design a short-term rental search and booking system, balancing eventual consistency in search discovery with strict consistency during reservations and checkout.
System DesignTechnical Screensystem-designconcurrencydistributed-systems - HeadwayMediumSoftware EngineerDesign a Shopping Cart Service That Keeps Inventory Consistent Under Concurrency
Design the backend for an online store's shopping cart, with the focus on inventory consistency: when stock is reserved, how two shoppers racing for the last unit are resolved, and how abandoned holds are released. It tests data modeling, concurrency control, checkout failure handling and contention on popular items.
System DesignTechnical Screen - HeadwayMediumSoftware EngineerExplain a Challenging Project, Influence, and Mentorship
This question assesses a candidate's ability to articulate complex professional narratives, specifically focusing on technical leadership, conflict resolution, and the cultivation of junior talent.
Behavioral & LeadershipTechnical ScreenBehavioralLeadershipMentorship - HeadwayMediumSoftware EngineerGenerate Every Letter String a Phone Keypad Digit Sequence Can Spell
Given a string of digits from 2 to 9, return every letter string those digits can spell on a standard phone keypad, in lexicographic order. It tests systematic enumeration of combinations, keys that carry four letters, and producing a deterministic output order.
Coding & AlgorithmsTechnical Screen - HeadwayMediumSoftware EngineerHandle traffic spikes and estimate server capacity
This question evaluates a candidate's competency in performance troubleshooting, capacity planning, and scalable system architecture, focusing on diagnosing overload causes and quantifying infrastructure needs.
System DesignTechnical Screen - HeadwayHardSoftware EngineerImplement Journey Counter and Speeder Detector
This problem tests your ability to process time-series event data by grouping related actions, managing state across sequences, and performing geometric or threshold-based calculations.
Coding & AlgorithmsTechnical ScreenHash MapsTime-SeriesState Management - HeadwayMediumSoftware EngineerImplement Layered Endpoint and Global Rate Limits
This problem tests your ability to design a thread-safe, memory-efficient rate limiter that manages hierarchical quotas using a rolling window mechanism.
Software Engineering FundamentalsTechnical ScreenConcurrencyRate-LimitingAlgorithms - HebbiaMediumSoftware EngineerDesign Hebbia Chat for SEC Filings
This problem tests your ability to design a retrieval-augmented generation (RAG) system specialized for financial documents, focusing on multi-agent orchestration, citations, and latency management.
ML System DesignTechnical ScreenRAGLLMSystem Design - HebbiaMediumSoftware EngineerDesign a Multi-Agent Chat Backend
This question evaluates a candidate's ability to design scalable, reliable backend architectures that integrate LLMs and multi-agent orchestration, covering distributed systems, streaming responses, conversation context management, tool integrations, observability, and secure handling of sensitive financial data.
System DesignOnsite - HebbiaHardMachine Learning EngineerDesign a Multi-Agent Document Search and Visualization Product
This problem tests your ability to design a complex multi-agent orchestration system that integrates large-scale document retrieval with reliable citation tracking and a user-facing visualization interface.
ML System DesignOnsiteMulti-Agent SystemsRAGOrchestration - HebbiaHardSoftware EngineerDetect a Winner on a 3x3 Tic-Tac-Toe Board
This problem tests your ability to efficiently represent board states and implement win-condition logic for a grid-based game.
Coding & AlgorithmsOnsiteArraysLogicGames
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