Katkat

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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 451–480 of 3640 results

  • AnthropicMediumSoftware Engineer
    Find the Slowest Function from Profiler Events

    This question evaluates the ability to interpret time-ordered profiler event logs, compute inclusive and exclusive function runtimes, reason about call-stack semantics, and recognize anomalies such as recursion, cycles, missing end events, or non-returning functions.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    Fix a Buggy LRU Cache, Then Make It Durable with a Write-Ahead Log

    Debug a flawed least-recently-used cache by finding each bug with a reproducing call sequence and fixing it, then make the cache durable across crashes with a write-ahead log and snapshots. It tests careful code reading, constant-time LRU design, crash-consistent persistence and recovery.

    Software Engineering FundamentalsOnsite
  • AnthropicHardSoftware Engineer
    Function-Call LRU Cache: Argument Key Generation and Crash Recovery from a Log

    A Python exercise that builds an LRU cache for memoizing function calls. Part one asks how to generate a reliable cache key from a function and its arguments; part two adds crash recovery through an append-only log file, testing record framing, durability, torn writes and replay of the cache state.

    Software Engineering FundamentalsOnsite
  • AnthropicHardSoftware Engineer
    Guide and override compiler optimizations

    This question evaluates a candidate's competency in low-level performance engineering and compiler optimization techniques—covering pragmas, intrinsics, manual code transformations, profiling and correctness verification—within the System Design and compiler-aware optimization domain.

    System DesignOnsite
  • AnthropicMediumSoftware Engineer
    Hiring-Manager Behavioral Round: Impact, Conflict, Cross-Functional Work, and Influencing Without Authority

    Tests a candidate's ability to drive technical initiatives across teams, navigate cross-functional disagreements, and exert leadership without formal management authority.

    Behavioral & LeadershipOnsiteBehavioralLeadershipCross-Functional
  • AnthropicHardSoftware Engineer
    How do you design an A/B experiment?

    This problem tests your ability to design a rigorous A/B experiment for a consumer-facing AI product, focusing on identifying interference, selecting appropriate metrics, and addressing statistical validity.

    Analytics & ExperimentationOnsiteA/B TestingExperiment DesignMetrics
  • AnthropicHardSoftware Engineer
    How do you lead under risk and uncertainty?

    This question evaluates leadership competencies—risk assessment, stakeholder management, conflict resolution, and decision-making under uncertainty in engineering contexts.

    Behavioral & LeadershipOnsite
  • AnthropicHardSoftware Engineer
    How do you review a design document?

    This question assesses a candidate's ability to critically evaluate technical design documentation by identifying architectural risks, scalability bottlenecks, and gaps in operational planning.

    Software Engineering FundamentalsOnsiteSystem DesignCode ReviewReliability
  • AnthropicMediumSoftware Engineer
    How to Handle the First-Round Interview at an AI Safety Lab

    A structured prompt for the earliest conversation in the loop at a lab whose mission is AI safety, where most of the time goes to why you want to work there specifically and how you think about the risks of the technology, not resume review. Tests depth, specificity, and whether your safety views connect to real experience.

    Behavioral & LeadershipOnsitebehavioralmotivationai-safety
  • AnthropicMediumSoftware Engineer
    How to stream a large file to 1000 hosts fastest

    Design a high-throughput distribution system to broadcast a large file (e.g., 100 GB model checkpoint) to 1,000 cluster hosts in minimum time, analyzing network bottlenecks and replication topologies.

    System DesignOnsitedistributed-systemssystem-designnetworking
  • AnthropicMediumSoftware Engineer
    Implement Parallel Image Processing

    This question evaluates competency in concurrent and parallel processing, practical image manipulation with Python libraries (Pillow), resource management for memory and file I/O, robust error handling, and performance measurement.

    Coding & AlgorithmsOnsite
  • AnthropicHardSoftware Engineer
    Implement Persistent Memoization LRU Cache

    This problem tests your ability to design a decorator that memoizes function results using an LRU policy while ensuring the cache survives process restarts via disk serialization.

    Coding & AlgorithmsOnsitePythonLRU CacheDecorator
  • AnthropicMediumSoftware Engineer
    Implement Python LRU cache with args and persistence

    This question evaluates a candidate's ability to design and implement an LRU cache in Python that supports variable-length positional and keyword arguments with canonical, deterministic hashing for semantically equivalent calls and O(1) get/put via a hash map plus a doubly linked list; it falls under the Coding & Algorithms domain and primarily tests practical implementation skills, API robustness, hashing/equality subtleties, and algorithmic complexity guarantees. The persistence follow-up evaluates understanding of serialization and storage design — on-disk formats, versioning, and atomic write strategies — and compares trade-offs between binary pickle and JSON-based serialization in terms of security, compatibility, and performance, reflecting both conceptual design and practical system-level considerations.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    Implement Python LRU cache with varargs

    This question evaluates a candidate's ability to implement an LRU caching mechanism in Python, including decorator design, argument canonicalization for positional args, *args, and **kwargs, handling unhashable inputs, eviction semantics, cache metadata operations (clear, cache_info), and JSON-based persistence and versioning.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    Implement a Banking System

    This question evaluates skills in designing and implementing a stateful in-memory banking system, covering account modeling, transfer lifecycle and expiration handling, balance management, and tracking aggregate outgoing amounts.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    Implement a Least-Recently-Used Cache

    This question evaluates a candidate's ability to design and implement an efficient in-memory cache with eviction behavior, testing understanding of data structure selection, state management, and time/space complexity under capacity constraints.

    Coding & AlgorithmsOnsite
  • AnthropicHardSoftware Engineer
    Implement a Longest-Match Tokenizer

    Design and implement a greedy longest-match text tokenizer that validates vocabulary, supports configurable unknown-token coalescing, and emits token IDs alongside their exact substring matches.

    Coding & AlgorithmsOnsitetriestringnlp
  • AnthropicHardSoftware Engineer
    Implement a hierarchical file store

    This problem tests your ability to design a hierarchical file system data structure and implement operations for directory traversal, file manipulation, and path normalization.

    Coding & AlgorithmsOnsiteTreeTrieData Structures
  • AnthropicMediumMachine Learning Engineer
    Implement a web crawler using a provided API

    This problem tests your ability to design a multi-threaded web crawler that efficiently traverses a site while respecting domain constraints and avoiding redundant work.

    Coding & AlgorithmsOnsiteConcurrencyGraph TraversalBFS
  • AnthropicMediumMachine Learning Engineer
    Implement an extensible prefix tree

    This question evaluates the ability to design and implement an extensible prefix tree (trie), covering competencies in Unicode-aware string handling, memory and time optimization, concurrency or thread-safety considerations, and support for operations like insert, search, startsWith, countPrefix and erase.

    Coding & AlgorithmsOnsite
  • AnthropicHardSoftware Engineer
    Implement and analyze custom attention

    This question evaluates implementation and analysis skills for scaled dot-product attention, testing competencies in efficient tensorized PyTorch coding, numerical stability and mixed-precision handling, masking semantics (causal and padding), multi-head shape correctness, and unit-test validation including gradient and edge-case behavior.

    Machine LearningOnsite
  • AnthropicMediumSoftware Engineer
    Implement and derive backprop from scratch

    This question evaluates understanding and practical implementation of neural network fundamentals, specifically analytic backpropagation and gradient derivation, numerically stable binary cross-entropy computation, parameter initialization, gradient descent updates, and gradient checking.

    Machine LearningOnsite
  • AnthropicMediumSoftware Engineer
    Implement crawler, dedup, and persistent LRU

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Implement crawler, dedup, and persistent LRU states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    Implement file deduplication at scale

    Implement streaming file deduplication that filters by size, fingerprint and hash, then compares bytes to rule out hash collisions. It covers large-file chunking, batched disk I/O, parallelizing across cores or machines, a dry-run report, and hard links that never cross devices. Follow-ups turn it into a command-line tool that handles symbolic links, unreadable files, error cases, and options to move or delete duplicates.

    Coding & AlgorithmsOnsite
  • AnthropicHardSoftware Engineer
    Implement staircase printing and distributed mode/median

    This set of problems evaluates implementation correctness and attention to formatting for a staircase-printing routine alongside distributed-algorithms reasoning for computing a global mode/median, testing algorithmic thinking, I/O handling, synchronization, and communication-cost trade-offs in the Coding & Algorithms domain.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    Implement thread-safe blocking queue

    This question evaluates competency in concurrent programming, synchronization primitives, and implementation of thread-safe bounded blocking queues within the Coding & Algorithms domain.

    Coding & AlgorithmsOnsite
  • AnthropicMediumSoftware Engineer
    In-Memory Key-Value Database with Nested Transactions

    Design an in-memory key-value store supporting nested transactions with begin, commit, rollback, get, set, and delete operations.

    Coding & AlgorithmsOnsiteData StructuresStackDesign
  • AnthropicMediumSoftware Engineer
    LRU Cache

    This question tests the ability to combine a hash map and a doubly linked list to implement an LRU cache with O(1) performance for both get and put operations.

    Coding & AlgorithmsOnsiteHash MapDoubly Linked ListDesign
  • AnthropicHardSoftware Engineer
    Lead a Project Retrospective Discussion

    Lead a project retrospective that explains the hardest challenge, its root cause, and the alternatives considered. Separate personal ownership from team effort, support outcomes with evidence, acknowledge limitations, and show how the lesson changed later decisions.

    Behavioral & LeadershipOnsite
  • AnthropicMediumSoftware Engineer
    Make a Web Crawler Concurrent with Thread-Safe Visited State

    Convert a sequential crawler to bounded concurrency using atomic URL reservation, explicit retry state, and completion detection that accounts for active fetches.

    Software Engineering FundamentalsOnsite