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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
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 1261–1290 of 4616 results
- CreditkarmaMediumMachine Learning EngineerDesign Personalized Promotion Recommendations
This question tests the ability to design an end-to-end recommendation system for personalized financial promotions, focusing on handling sparse conversion data, real-time feature requirements, and feedback loops.
ML System DesignTechnical ScreenRecommendation SystemsRankingFeature Engineering - CrestaMediumSoftware EngineerDesign sequence decoding with greedy and beam search
This interview question evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer for Design sequence decoding with greedy and beam search states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Machine LearningTechnical Screen - CrestaMediumSoftware EngineerJob Dispatcher with Least-Loaded, Round-Robin Assignment and Executor Removal
A coding exercise to implement Executor and JobDispatcher classes that send each integer job ID to the executor with the fewest pending jobs, breaking ties round-robin, while executors join and leave. It tests precise tie-break semantics, consistent load tracking, reassigning a removed executor's queued jobs, and edge cases.
Software Engineering FundamentalsTechnical Screen - CrestaEasySoftware EngineerProductionize a Successful Proof of Concept
Explain how to take a successful proof of concept into production, including the engineering and operational gaps that must be closed.
System DesignTechnical Screen - CriblMediumSoftware EngineerDesign an LLM Log Parsing Workflow
This question evaluates skills in ML-enabled log parsing, schema inference, structured data extraction, and designing scalable, reliable production workflows that combine probabilistic LLMs with deterministic parsers and operational engineering.
ML System DesignTechnical Screen - CrowdstrikeMediumSoftware EngineerDesign scalable worker pool for template jobs
This question evaluates a candidate's competency in designing scalable, concurrent backend systems, covering distributed worker pools, producer–consumer patterns, queuing, load balancing, fault tolerance, backpressure, and domain-specific considerations like template parsing and caching.
System DesignTechnical Screen - CrowdstrikeMediumBackend EngineerImplement a Risk-Score Priority DetectionStore With Put and GetNext in C++
Implement a C++ DetectionStore whose Put stores security detections with an id, an unsigned risk score and a payload, and whose GetNext removes and returns the next detection by risk score as a unique_ptr. Tests priority-structure choice, ownership semantics, tie and duplicate-id policies, and thread safety.
Software Engineering FundamentalsTechnical Screen - CrusoeMediumSoftware EngineerCalculate charge with a single price override
This problem tests your ability to handle overlapping time intervals and apply conditional overrides to calculate the total charge for a billing period.
Coding & AlgorithmsTechnical ScreenIntervalsArraysLogic - CubistMediumSoftware EngineerDesign a class to submit jobs with dependencies and track their status
Design and implement a job tracker class that accepts job submissions with dependencies, hands out jobs that are ready to run, and reports each job's status. It tests state-machine design, dependency-graph bookkeeping, handling of failures and cycles, and thread safety when several workers call the class at once.
Software Engineering FundamentalsTechnical Screen - CubistMediumSoftware EngineerDesign a reusable event-driven framework for trading strategies
Design a reusable, event-driven framework for trading strategies that a team can keep extending after a take-home handoff. It tests event modeling and dispatch ordering, strategy interfaces, backtest and live parity, order and risk management, and the tests and documentation that make a framework maintainable.
Software Engineering FundamentalsTechnical Screen - CubistMediumSoftware EngineerRebuild a binary search tree from its postorder traversal in linear time
Rebuild a binary search tree with distinct values from its postorder traversal and return the rebuilt tree's preorder traversal. The problem tests BST ordering properties, traversal orders, and meeting a strict O(n) time bound on inputs that include deeply skewed trees.
Coding & AlgorithmsTechnical Screen - CurrentMediumSoftware EngineerDescribe a previous project and outcomes
Describe a previous project and outcomes evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - CurrentHardSoftware EngineerDesign a metrics monitoring system
Design a metrics monitoring system evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - CursorMediumSoftware EngineerBuild a Merkle Tree over a Directory with Hash Lookup and Tree Diff
Implement a Merkle tree over a real directory in Python, with N-ary directory nodes, a build method, a hash lookup by path, and a diff that compares two trees, and write the tests yourself. It tests deterministic hashing design, file-system traversal, pruning identical subtrees, and disciplined testing under time pressure.
Software Engineering FundamentalsTechnical Screen - CursorHardSoftware EngineerBuild a Streaming Markdown Code Fence Parser
Tests streaming string processing, finite state machine design, and edge-case handling for incrementally received Markdown code fences.
Software Engineering FundamentalsTechnical ScreenStreamingFinite State MachineParsing - CursorMediumSoftware EngineerConnect a Project Deep Dive to Engineering Career Decisions
Connect a technical project deep dive with engineering career decisions, using clear ownership, interface trade-offs, validation, and lessons learned.
Behavioral & LeadershipTechnical Screen - CursorMediumBackend EngineerDesign Scalable Notification Rate Limiter
This question evaluates expertise in designing distributed rate-limiting systems with hierarchical quotas, focusing on concurrency control, exact rolling-window counting, and correctness under concurrent stateless servers; it belongs to the System Design domain and tests practical application of distributed systems, storage, and API design as well as conceptual understanding of atomicity and consistency. It is commonly asked to assess reasoning about atomic decision-making across multiple scopes, scalability and partitioning strategies, handling reconfiguration and operational concerns, and the trade-offs between correctness and system performance (English).
System DesignTechnical Screen - CursorMediumSoftware EngineerDesign Versioned IDE Settings for Users and Teams
Design a distributed, hierarchical configuration management service for an IDE that synchronizes versioned settings across individual users, multiple teams, and workspaces while supporting offline modifications and deterministic conflict resolution.
System DesignTechnical ScreenDistributed SystemsOffline SyncData Modeling - CursorMediumSoftware EngineerDesign a Durable Cron Job Scheduler
Design a cron scheduler with durable occurrences, timezone rules, missed-run policies, worker leases, idempotent dispatch, and failure recovery.
System DesignTechnical Screen - CursorMediumSoftware EngineerHash a Repository with a Merkle Tree and Find Changed Files
Hash a repository with canonical Merkle nodes, compare changed subtrees, report file changes, and account for symlinks, cached hashes, and snapshot limits.
Software Engineering FundamentalsTechnical Screen - CursorMediumSoftware EngineerImplement Deterministic Merkle Hashing for a Repository
Implement an incremental, deterministic Merkle tree for a virtual repository file system with stable serialization, child ordering, and ancestor cache invalidation.
Software Engineering FundamentalsTechnical ScreenMerkle TreeData StructuresFile Systems - CursorMediumSoftware EngineerImplement a Merkle Tree for Repository Contents
Implement a Merkle tree to model repository file systems and efficiently compute differences between two repository states using subtree hashes.
Software Engineering FundamentalsTechnical ScreenMerkle TreeTreesHashing - CursorHardSoftware EngineerImplement a Merkle-tree repo diff
This question evaluates a candidate's understanding of Merkle trees, filesystem-aware hashing, directory traversal, and diff algorithms for detecting file-level changes.
Coding & AlgorithmsTechnical Screen - CursorMediumSoftware EngineerImplement and Explain a Merkle Tree
Tests understanding of cryptographic hash trees (Merkle trees), including tree construction, odd-node handling, proof generation, and verification.
Software Engineering FundamentalsTechnical Screencryptographydata-structurestrees - DRWMediumData ScientistDifferentiate sample vs population standard deviation
This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Differentiate sample vs population standard deviation states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Statistics & MathTechnical Screen - DRWEasySoftware EngineerFewest Expenses to Defer to Year End So the Running Balance Never Goes Negative
Given a year's transactions in order, with income as positive values, expenses as negative values and a non-negative total, find the fewest expenses to move to the end of the year so the running balance never drops below zero. It tests reasoning over prefix sums for inputs of up to 100,000 transactions.
Coding & AlgorithmsTechnical Screen - DRWEasySoftware EngineerLongest Substring in Which Every Present Letter Occurs Equally Often
Given a string of lowercase letters, find the length of the longest substring in which every letter that appears occurs the same number of times. It tests substring enumeration with incremental frequency tracking and a precise definition of what counts as balanced.
Coding & AlgorithmsTechnical Screen - DRWEasySoftware EngineerMinimize the Max-Min Gap of an Array After Changing Up to Three Elements
Given an integer array, you may change up to three elements to any values; return the smallest possible difference between the largest and smallest values afterward. It tests reasoning about which extreme values are worth changing and careful handling of short arrays.
Coding & AlgorithmsTechnical Screen - Dark Alpha CapitalMediumSoftware EngineerMinimize Total Assignment Distance
This question evaluates competency in combinatorial optimization, assignment/matching problems, and reasoning about Manhattan distance cost metrics. Commonly asked to assess algorithmic reasoning about constrained assignments, search and complexity trade-offs, it belongs to the Coding & Algorithms domain and emphasizes practical application of algorithm design and implementation rather than purely conceptual theory.
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerCheck if CIDR is fully canceled by rules
This question evaluates understanding of IPv4 CIDR arithmetic, set operations on IP ranges (overlap detection and subtraction), and ordered rule semantics for allow/deny processing.
Coding & AlgorithmsTechnical Screen
Cresta
Crowdstrike
Cursor
DRW
Databricks